**Endoscopic Intracranial Imaging**

Oscar H. Jimenez-Vazquez

*"Dr. Miguel Silva" Hospital General Morelia, Michoacan, Mexico* 

### **1. Introduction**

338 Neuroimaging – Methods

Yamada, T.; Hattori, H.; Miura, A.; Tanabe, M. & Yamori, Y. (2001). Prevalence of

Yamada, T.; Kadekaru, H.; Matsumoto, S.; Inada, H.; Tanabe, M.; Moriguchi, E. H.;

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1351-5101

Alzheimer's disease. *Brain : A Journal of Neurology,* Vol.130, No.Pt 3, pp. 708-719,

Alzheimer's disease, vascular dementia and dementia with Lewy bodies in a Japanese population. *Psychiatry and Clinical Neurosciences,* Vol.55, No.1, pp. 21-25,

Moriguchi, Y.; Ishikawa, P.; Ishikawa, A. G.; Taira, K. & Yamori, Y. (2002). Prevalence of dementia in the older Japanese-Brazilian population. *Psychiatry and* 

metabolism in Parkinson's disease, Parkinson's disease dementia and dementia with Lewy bodies. *European Journal of Neurology : The Official Journal of the European Federation of Neurological Societies,* Vol.14, No.12, pp. 1357-1362, ISSN 1468-1331;

incidence studies of dementia with Lewy bodies. *Age and Ageing,* Vol.34, No.6, pp.

The fundamental aim of the chapter is to create awareness in the general medical community about the benefits of neuroendoscopy imaging for prompt and effective diagnosis and treatment of lesions within or adjacent to fluid-filled intracranial cavities.

Neuroendoscopy is a surgical diagnostic and therapeutic modality that has suffered an oscillating course in history, regarding its indications and applications. At present, it enjoys another thrust of popularity, which may be evident by the increasing number of publications and academic events world-wide related to this discipline. It has been evolving continuously, allowing for new indications, applications, and results.

Neuroendoscopy is not a novel technique. According to a large number of articles and books, the application of lenses to observe internal parts of the body without a wide exposure, was initiated in the 19th century, and such technology was soon applied to the intracranial space. Very primitive equipment was used to explore the ventricular system and to excise the choroid plexus. Since the beginning of this new technology, it has suffered continuous modifications that have improved optical quality and surgical capability, resulting in better surgical outcome (1).

As a typical example of a minimally invasive neurosurgical technique, neuroendoscopy has led to improvement in diagnosis, therapy, and prognosis in many intracranial lesions. Practically all intracranial compartments may be reached with an endoscope, whether it is rigid or flexible, and indications have increased dramatically. It is now possible to diagnose and treat through direct observation intraventricular, as well as subarchnoid and parenchymal lesions.

Hoping to avoid a shunt placement and its complications, third-ventriculostomies were initially adopted as promising procedures for most cases of hydrocephalus. Although it has not been associated with the postoperative results that were hoped for, it has today very clear indications. Hypertensive and obstructive hydrocephalus due to different pathologies in the cerebral aqueduct, the posterior part of the third ventricle, or the fourth ventricle, may be some of the ideal cases for a third-ventriculostomy. Although some factors may vary when performing a third ventriculostomy, such as early age, a final word has not been said in this regard, since the controversy continues. Shunt systems, nevertheless, continue to be an important part of the instruments needed in the treatment of hydrocephalus.

Congenital cysts in or adjacent to the ventricular system acting as space occupying lesions and hydrocephalus may be another clear indication for endoscopic exploration and cavity communication, sometimes requiring a shunt system. Although not as frequent as the

Endoscopic Intracranial Imaging 341

Hydrocephalus. No visible cause.

hydrocephalus. Cysticercal ependymitis. 3rd ventricle calcifications.

hydrocephalus. Ependymitis. Intraventricular septi and/or 3rd ventricle

cysticerci.

Parenchymal calcifications. Global hydrocephalus.

3rd. ventricle

involvement.

invasion.

Thalamic tumour with

infiltration and shunt

hydrocephalus. 3rd ventricle tumour

Cysticercal basal arachnoiditis.

**8 30 M** RICP. Left ventricular cyst. Septum in ventricle

hydrocephalus. Cerebellar tumour with 3rd ventricle

Supratentorial hydrocephalus.

invasion.

atrophy.

Pneumocephalus with hydrocephalus.

**Diagnosis Image Diagnosis Endoscopic Diagnosis Ct/Endo** 

Adherence of the catheter to choroid

Ventriculomegaly with NO ependymitis or calcification.

Ventriculomegaly with NO ependymitis, cysticerci or septi.

Ventricular

compression with NO tumour infiltration. Catheter in interventricular septum\*.

3rd ventricle tumour invasion with ventriculomegaly.

Multiple ependymal calcifications. Ventriculomegaly.

without cystic lesion.

Ventriculomegaly

pneumocephalus.

Ventriculomegaly with NO 3rd ventricle

Determination of callosotomy extent.

Ventriculomegaly. YES NO

with

invasion.

Ventriculomegaly. YES NO

plexus.

**Correl** 

NO NO

NO YES

NO YES

NO/ NO

NO NO

YES NO

NO YES

YES NO

NO YES

YES NO

YES/ YES

**Tx Modif** 

**Case Age Sex Clinical** 

**4 43 M** RICP;

**9 42 F** CSF

**11 57 M** RICP,

**1 30 M** RICP, SD. Global

**2 19 M** RICP. Supratentorial

**3 17 M** RICP. Supratentorial

Dementia.

**5 26 F** RICP, SD\*. Hydrocephalus.

**6 26 F** RICP. Supratentorial

fistula, SD.

**10 34 M** RICP. Supratentorial

Dementia.

**12 18 F** Epilepsy. Mild global cortical

**7 39 M** RICP. Global hydrocephalus.

previous case, septum cavum pellucidum cysts have been other clear indications for endoscopic fenestrations, either with mechanical means (like the endoscope itself) or with laser beams. In such cases raised intracranial pressure is normalized and symptomatology slowly resides.

Catheter placements and revisions may represent frequent indications for endoscopic shunt revisions, given the large number of shunt operations that take place daily throughout the world, so dysfunction of these systems are to be expected. The causes for shunt dysfunction are many, but may not be evident with image studies (CT or MRI scans), therefore intraventricular endoscopy offers a direct diagnostic method which may yield clear images in real time. It also allows the opportunity to apply therapeutic measures during the same operation.

Haematoma drainage, membrane fenestrations, tumour biopsies and resections, and open neurosurgical assistance, may be other common procedures that may be assisted with the endoscope. Although indications may vary according to the local neuropathological illnesses and diagnostic capabilities, it is largely dependent on the neurosurgeons experience.

As published elsewhere (2), there is a need to stress that precise diagnosis is a key factor for a correct planning of a successful neuroendoscopic procedures, since conventional image studies may be deficient in resolution. This is certainly the case in modest medical facilities, where computed tomography (CT) and magnetic resonance imaging (MRI) scanners may not be available or updated. This fact may represent a high proportion of primary medical care systems world-wide, and it is certainly true for hospitals of our community. To demonstrate this fact, the results obtained in our series of endoscopy cases, preoperative image studies (CT and MRI) have yielded unparallel results compared with those obtained with endoscopy in roughly half of the cases. This is especially true in the beginning of the case recollection, because image studies were more primitive than the images obtained from more modern machines, and the images were more modest in resolution.

Neuroendoscopy may yield high quality images which may confirm or discard diagnostic possibilities during the surgical procedure, making often times in-situ modifications necessary. Derived from the previous statement, and because the original preoperative diagnosis was different from the intraoperative endoscopical image, the surgical treatment that was finally performed was different from the one originally planned in about a third of the cases. In this context, other surgical procedures, including open procedures, were avoided, and therefore additional risks and costs to the patient were reduced.

Neuroendoscopy in our hospitals has been performed by the same neurosurgeon in 102 procedures. With its limitations, it has demonstrated benefits, as well as drawbacks. Among the former, accuracy in diagnosis of lesions that were subject to several differential diagnosis, especially when they were based on low definition image studies. Full details of our cases can be observed in table 1.

Endoscopy equipment, in our experience, has changed through different times. Initially, a pediatric cystoscope was used and procedures were limited to observations and few cystic perforations. Septostomies also were commonly performed. Most of these procedures were not recorded in image documents. The same was true for a second generation of instruments, which included a semi-rigid, 2mm diameter fibroscope, a new light source, but no camera or video-recorder. Our present endoscope is a 4mm rigid Richard Wolf, with three working channels, a video system and a high definition screen.

previous case, septum cavum pellucidum cysts have been other clear indications for endoscopic fenestrations, either with mechanical means (like the endoscope itself) or with laser beams. In such cases raised intracranial pressure is normalized and symptomatology

Catheter placements and revisions may represent frequent indications for endoscopic shunt revisions, given the large number of shunt operations that take place daily throughout the world, so dysfunction of these systems are to be expected. The causes for shunt dysfunction are many, but may not be evident with image studies (CT or MRI scans), therefore intraventricular endoscopy offers a direct diagnostic method which may yield clear images in real time. It also allows the opportunity to apply therapeutic measures during the same

Haematoma drainage, membrane fenestrations, tumour biopsies and resections, and open neurosurgical assistance, may be other common procedures that may be assisted with the endoscope. Although indications may vary according to the local neuropathological illnesses and diagnostic capabilities, it is largely dependent on the neurosurgeons

As published elsewhere (2), there is a need to stress that precise diagnosis is a key factor for a correct planning of a successful neuroendoscopic procedures, since conventional image studies may be deficient in resolution. This is certainly the case in modest medical facilities, where computed tomography (CT) and magnetic resonance imaging (MRI) scanners may not be available or updated. This fact may represent a high proportion of primary medical care systems world-wide, and it is certainly true for hospitals of our community. To demonstrate this fact, the results obtained in our series of endoscopy cases, preoperative image studies (CT and MRI) have yielded unparallel results compared with those obtained with endoscopy in roughly half of the cases. This is especially true in the beginning of the case recollection, because image studies were more primitive than the images obtained from

Neuroendoscopy may yield high quality images which may confirm or discard diagnostic possibilities during the surgical procedure, making often times in-situ modifications necessary. Derived from the previous statement, and because the original preoperative diagnosis was different from the intraoperative endoscopical image, the surgical treatment that was finally performed was different from the one originally planned in about a third of the cases. In this context, other surgical procedures, including open procedures, were

Neuroendoscopy in our hospitals has been performed by the same neurosurgeon in 102 procedures. With its limitations, it has demonstrated benefits, as well as drawbacks. Among the former, accuracy in diagnosis of lesions that were subject to several differential diagnosis, especially when they were based on low definition image studies. Full details of

Endoscopy equipment, in our experience, has changed through different times. Initially, a pediatric cystoscope was used and procedures were limited to observations and few cystic perforations. Septostomies also were commonly performed. Most of these procedures were not recorded in image documents. The same was true for a second generation of instruments, which included a semi-rigid, 2mm diameter fibroscope, a new light source, but no camera or video-recorder. Our present endoscope is a 4mm rigid Richard Wolf, with

more modern machines, and the images were more modest in resolution.

avoided, and therefore additional risks and costs to the patient were reduced.

three working channels, a video system and a high definition screen.

our cases can be observed in table 1.

slowly resides.

operation.

experience.


Endoscopic Intracranial Imaging 343

Hydrocephalus. Multiple parenchymal calcifications and cysts.

Supratentorial hydrocephalus.

pellucidum cyst.

ventricle.

lobe.

Parenchymal

Supratentorial hydrocephalus.

ventricles.

haemorrhage in frontal

matter interface in left temporal lobe. Normal

hydrocephalus. Right supra- infratentorial arachnoid cyst.

Porencephalic cyst.

Supratentorial hydrocephalus. 4th ventricle cyst.

Supratentorial hydrocephalus.

Supratentorial hydrocephalus with ependymitis.

**Diagnosis Image Diagnosis Endoscopic Diagnosis Ct/Endo** 

Ventriculomegaly with adhesive

Ventriculomegaly with a small viable cysticercus in choroid

Dilated, isolated and hypertensive septum pellucidum cyst.

Dilated left temporal lateral ventricle.

Parenchymal haemorrhage in frontal lobe.

Severe adhesive 3rd ventricle ependymitis.

ventricle.

Narrow left temporal

Ventriculomegally. Right suprainfratentorial arachnoid cyst.

Cyst independent from dilated ventricles.

Ventriculomegaly with extensive intraventricular

Ventriculomegaly with NO ependymitis. Abundant fibrosis in 3rd (with small compartments) and lateral ventricles\*.

Ventriculomegaly. YES NO

fibrosis.

plexus.

ependymitis. NO cysts.

**Correl** 

NO NO

NO YES

YES NO

YES NO

YES NO

NO NO

YES NO

YES NO

YES NO

NO NO

NO/ NO

YES/ YES

**Tx Modif** 

**Case Age Sex Clinical** 

**25 77 F** Headache,

**26 77 M** RICP,

**29 65 M** RICP,

**30 19 M** RICP, SD,

**34 30 M** RICP, SD.

**35 50 M** RICP,

**36 35 M** RICP,

seizures.

coma.

coma.

infection.

**32 37 F** RICP. Supratentorial

**33 27 M** Dementia. Hydrocephalus.

Left hemiparesis

social neglect.

of infection.

signs and symptoms

**31 32 F** Epilepsy. Loss of white-gray

**27 18 F** RICP. Compressive septum

**28 29 F** Epilepsy. Dilated left temporal


**13 28 M** RICP, SD. Global hydrocephalus. Ventriculomegaly.

**14 31 F** RICP. Global hydrocephalus. 3rd ventricle septum.

Supratentorial hydrocephalus. Porencephalic cyst NOT communicated with ventricles.

cystic tumour with

hydrocephalus. Two ventricular catheters.

Thalamic tumour.

Subacute subdural hematoma with septi.

3rd and left lateral

Septum in right lateral ventricle. Pineal calcification within the

ventricle hydrocephalus. Purulent ependymitis.

3rd ventricle.

Cortical cyst.

Hydrocephalus. 3rd ventricle displacement by arachnoid cyst.

ventricular deformation. Hydrocephalus.

Occipital tumour with

septi.

**Diagnosis Image Diagnosis Endoscopic Diagnosis Ct/Endo** 

Multiple intraventricular adherences\*.

Ventriculomegaly.

Partial communication of cyst to dilated ventricles.

Parietal tumour with independent cysts.

Fibrosis of 3rd ventricle

catheter. Adherence of second catheter to choroid plexus.

Ventriculomegaly. Callosotomy assistence\*.

Extrinsic 3rd ventricle dysplacement. Ventriculomegaly.

Ventriculomegaly and abundant adherences\*

NO septum. Pineal calcification not

Discrete 3rd ventricle with adherences in the lateral ventricle. Ventriculomegaly.

Ventriculomegaly. YES NO

NO septi in hematoma.

No purulent ependymitis.

visible.

floor with one

**Correl** 

NO YES

NO YES

YES NO

NO YES

YES NO

NO YES

NO YES

NO YES

NO NO

NO/ NO

YES/ YES

NO/ NO

**Tx Modif** 

NO/ NO

**Case Age Sex Clinical** 

**15 29 M** RICP,

**19 54 F** RICP;

**20 60 M** RICP,

**21 52 M** RICP, SD,

**24 46 M** Stroke

Dementia.

**16 32 F** Seizures. Right parietal lobe

**17 17 M** RICP, SD. Supratentorial

**18 21 M** RICP. Hydrocephalus.

Dementia.

Hemipare sis.

Infection.

**23 46 M** RICP. Hydrocephalus.

with dysartria and hemiparesis

**22 43 M** RICP. Global hydrocephalus.


Endoscopic Intracranial Imaging 345

3rd ventricle and basal

hydrocephalus with widened infundibular

Cystic hypodense

Three ventricle

Three ventricle

hydrocephalus.

3-ventricle hypertensive hydrocephalus

hydrocephalus, corpus callosum agenesis, cephalic catheter in brain tissue.

hydrocephalus, corpus callosum and septum agenesis, cephalic catheter in ventricle.

tumour.

cisterns.

recess.

**Diagnosis Image Diagnosis Endoscopic Diagnosis Ct/Endo** 

Viable cysticerci in 3rd ventricle contained

Ventriculomegaly with widened infundibular recess.

Global hydrocephalus. Ventriculomegaly. YES NO

wall

tissue.

Cerebral surface cyst

Ventriculomegaly, ventricular septum agenesis, cephalic catheter in brain

Ventriculomegaly, ventricular septum agenesis, granular ependymitis, cephalic catheter in ventricle.

Turbid dense liquid, pale tissue covering ependymal walls, with adhesive clots and membranes

Isolated right ventricle YES NO

in turbid fluid, obstructing visualization of the floor.

**Correl** 

YES NO

YES NO

YES NO

YES NO

NO NO

NO YES

**Tx Modif** 

**Case Age Sex Clinical** 

**52 54 M** RICP,

**53 34 F** RICP,

**54 15 M** RICP, SD,

**55 21 M** RICP, SD,

**57 25 M** RICP,

**50 56 M** RICP. Hypodense images in

**51 42 F** RICP. Supratentorial

mood changes, episodic fever.

Right frontal cystic tumour

Arnold-Chiari.

Arnold-Chiari.

**56 32 M** RICP. Left and 3rd ventricle

dizziness, confusion, dementia, meningeal signs. HIV +


**Diagnosis Image Diagnosis Endoscopic Diagnosis Ct/Endo** 

Ventriculomegaly. Turbid CSF poor

Intraventricular electrode placement

Ventriculomegaly.

Narrow ventricle. Failed endoscopy.

Ventriculomegaly. Ventriculomegaly. YES NO

visualization.

Hypertrophic ependymitis with fibrous deposits in the III ventricle floor. Generalized tissue

paleness.

Normal pressure ventriculomegaly due to Munro foramen obstruction.

Three ventricle dilatation with thin 3rd ventricle floor.

Ventriculomegaly, Munro foramen obstruction due to arachnoid membranes.

Viable cysticerci with scolex contained in turbid fluid\* (both endoscopies).

Ventriculomegaly. Granular ependymitis.

Fibrous bands and ependymitis with Monroe obstruction.

Bloody tumour bed. -- --

control.

**Correl** 

YES NO



NO NO

NO YES

NO YES

NO YES

YES NO

NO YES

NO/ NO

YES/ YES

**Tx Modif** 

**Case Age Sex Clinical** 

**39 41 F** Arnold

**40 46 M** Brain

**43 45 M** Chiasmal

**45 42 M** Vague

**46 27 M** Postra-

**47 23 M** Postra-

**48 26 F** Amenor-

**49 47 M** Epilepsy,

**37 46 M** Epilepsy. Left temporal lobe

**38 21 M** Epilepsy. Left temporal lobe

Chiari and RICP.

injury sequels.

**42 23 M** RICP. Universal

**41 19 M** RICP. Supratentorial

syndrome.

neurological symptoms.

umatic hydrocephalus.

umatic hydrocephalus.

rhoea, galactorrhoea, and mild headache.

dementia.

atrophy.

epileptogenic focus.

hydrocephalus.

hydrocephalus.

Hypophyseal macroadenoma.

Universal

**44 35 F** Acromegaly Supratentorial tumour. Bloody tumour bed. -- --

hydrocephalus. HIV +.

Dilated independent supratentorial ventricles.

Supratentorial ventriculomegaly.

Hydrocephalus,

ventriculomegally

Hydrocephalus, Multiple cerebral cysticerci.

Lateral

with sellar arachnoidocele.


Endoscopic Intracranial Imaging 347

Hydrocephalus, right hemisphere cerebellar

Hydrocephalus and a

tumour.

Three-ventricle hydrocephalus, occluded aqueduct.

4th ventricle hemorrhage

Three-ventricle hydrocephalus, occluded aqueduct.

Hydrocephalus, thalamic tumour with

Three-ventricle hydrocephalus.

hydrocephalus

Hydrocephalus, ventricular cysticerci

Cystic lesions in Sylvian sulcus

Three-ventricle asymmetric hydrocephalus, occluded aqueduct.

3rd ventricle involvement.

**Diagnosis Image Diagnosis Endoscopic Diagnosis Ct/Endo** 

**Correl** 

NO NO

NO YES

NO YES

NO YES

NO NO

NO YES

NO YES

NO YES

Ventriculomegaly. YES NO

Ventriculomegaly YES NO

Ventriculomegaly, prepontine and premesencephalic adherences.

Ventriculomegaly and an active 3rd ventricle

hemorrhage.

Ventriculomegaly, pale granular

Ventriculomegaly, adhesive arachnoiditis in premesencephalic and prepontine

Ventriculomegaly, cisternal cysticercosis

Ventriculomegal, aracnoid cyst

Epidermoid in Sylvian

Ventriculomegaly, ependymitis with opaque epithelia.

cistern.

sulcus.

ependyma, no tumour in 3rd ventricle.

**Tx Modif** 

**Case Age Sex Clinical** 

**69 33 M** Headache,

**70 39 M** RICP,

**71 73 F** Sudden

**72 61 F** Hakim-

**73 40 M** RICP,

**74 41 F** RICP,

**76 67 M** Headache,

**77 65 M** Headache,

**78 72 M** Hakim-

dizziness, ataxia.

dizziness.

dysphasia and headache.

Adams triad, progressive headache

headache, confusion, fever, meningeal signs, ataxia. HIV +

previous posterior fossa operation

**75 31 M** RICP Three-ventricule

tremor, confusion, incoherent language

aggressive behavior, somnolence

Adams triad, progressive headache


Hydrocephalus, granular ependymitis.

Triventricular hydrocephalus.

**60 33 M** RICP. Hydrocephalus Ventriculomegaly,

Viable cysticerci in brain parenchyma and

Hydrocephalus, 3rd ventricle and cisternal

Hydrocephalus, pineal tumour with possible

frontotemporoparietal

Hydrocephalus, rare images in 3rd ventricle

cisterns.

cysticerci.

3rd ventricle involvement.

Right

cyst.

floor.

**65 44 M** RICP. Shunt dysfunction. Cysticercus in shunt

**Diagnosis Image Diagnosis Endoscopic Diagnosis Ct/Endo** 

Ventriculomegaly, granular ependymitis with café au lait spots

Ventriculomegaly with severe septum

and verrucae, 3rd ventricle floor

stiffness.

lacerations.

verrucae.

Hydrocephalus. Ventriculomegaly,

severe septum lacerations, granular ependymitis and

Viable parenchymal and cisternal cysticerci.

Ventriculomegaly, 3rd ventricle and cisternal cysticerci.

Ventriculomegaly, pineal tumour with

Cystic breast cancer

fibrous ependymal and cisternal bands, atrophic choroid

Ventriculomegaly. NO NO

cysticercus in shunt tip.

3rd ventricle involvement.

metastasis.

plexus.

tip.

Severe hydrocephalus. Ventriculomegaly,

**Correl** 

NO NO

YES NO

NO NO

YES NO

YES NO

NO NO

YES NO

NO NO

YES NO

NO NO

**Tx Modif** 

**Case Age Sex Clinical** 

Incoherent language, Dizzyness

diplopia.

seizures.

cysticercos

dysfunctio

ataxia, Parinaud, diplopia.

hemiparesis.

macroceph alus

dizziness

is.

n

**58 57 M** RICP.

**59 39 F** RICP,

**61 44 M** Headache,

**62 44 M** RICP,

**63 44 M** Shunt

**64 58 M** RICP,

**66 28 F** RICP, left

**67 40 F** RICP.

**68 16 F** Headache,


Endoscopic Intracranial Imaging 349

**90 32 F** RICP Hydrocephalus Ventriculomegaly YES NO

Three-ventricle hydrocephalus, cisternal cysticercosis

Three-ventricle hydrocephalus.

Three-ventricle hydrocephalus, cystic cerebellar tumour

Three-ventricle hydrocephalus, thalamic tumour.

shunted ventricles.

Communicating hydrocephalus

hydrocephalus

Three-ventricle

roof

hydrocephalus, colloid cyst in 3rd ventricle

hydrocephalus, colloid cyst in 3rd ventricle

sylvian fissure

Three-ventricle hydrocephalus, third ventricle tumour

**97 33 M** RICP Hydrocephalus Ventriculomegaly YES NO

**Diagnosis Image Diagnosis Endoscopic Diagnosis Ct/Endo** 

Ventriculomegaly, cisternal cysticercosis

Ventriculomegaly, mild arachnoiditis

Endoscopy-assisted

haemangioblastoma

Ventriculomegaly, 3rd ventricle compression, sponge-like tumour.

Ventriculomegaly, intracystic cysticerci, isolated from shunt tip

Ventriculomegaly, cisternal fibrosis unable to pass the endoscope

Ventriculomegally, colloid cyst. Partial resection in second

Ventriculomegaly, colloid cyst. Total resection through vellum interpositum

Thick and stiff onionskin cystic walls. Cystic communication to basal cisterns

Ventriculomegaly, third ventricle craniopharyngioma

endoscopy

Ventriculomegaly YES NO

resection of

**Correl** 

YES NO

NO NO

YES NO

YES NO

NO YES

NO YES

YES/ YES

YES NO

YES NO

NO/ YES

YES/ YES

NO/ NO

**Tx Modif** 

**Case Age Sex Clinical** 

**88 64 M** Dysartria,

**89 69 F** Headache,

**91 37 F** RICP,

**92 26 M** RICP,

**94 42 F** RICP,

**96 40 F** RICP,

**100 53 M** RICP,

ataxia, dementia, headache

seizures, aphasia, weakness

ataxia, vertigo

ophtalmoplegia, somnolence

**93 37 M** RICP Isolated cyst from

seizures

**95 48 M** RICP Three-ventricle

colloid cyst in the 3rd ventricle

**98 37 F** RICP Three-ventricle

dementia

**99 16 F** Epilepsy Arachnoid cyst in left


Hydrocephalus, diencephalic lesion affecting 3rd ventricle.

Three-ventricle hydrocephalus, increased prepontine

cistern, brain calcifications.

Brain stem tumour with 3rd and 4rd ventricle involvement.

hydrocephalus, cisternal cysticerci. Post ETV and cysticercal removal. Hydrocephalus.

cysticercal removal. Hydrocephalus.

ventricle tumour.

Three-ventricle hydrocephalus.

Hydrocephalus, ependymitis.

hydrocephalus.

**Diagnosis Image Diagnosis Endoscopic Diagnosis Ct/Endo** 

Ventriculomegaly, thinning and protruding cyst in 3rd ventricle wall.

Ventriculomegaly, cysticerci in prepontine and premesencephalic

Ventriculomegaly, tumour invading 3rd ventricle.

Ventriculomegaly, cisternal cysticercosis.

Ventriculomegaly, severe ventriculitisarachnoiditis. Ventriculomegaly, severe ventriculitisarachnoiditis

Ventriculomegaly,

Ventriculomegaly, granular ventriculitis and arachnoiditis

Ventriculomegaly, cisternal cysticercosis

Ventriculomegaly. YES NO

tumour in 3rd ventricle.

cistern.

**Correl** 

NO YES

YES NO

YES NO

YES NO

NO/ YES

YES NO

YES YES

YES NO

NO/ NO

**Tx Modif** 

**Case Age Sex Clinical** 

**80 40 F** Seizures,

**81 27 M** RICP,

hemiparesis, memory dysfunction, visual and auditive hallucinations.

RICP.

ataxia, dystonia.

**82 54 M** RICP. Three-ventricle

**83 54 M** RICP Post ETV and

**84 39 F** RICP Hydrocephalus, 3rd

memory loss.

myalgia.

**87 59 M** RICP. Three-ventricle

**85 62 F** Headache,

**86 33 M** RICP,

**79 81 M** Right


Endoscopic Intracranial Imaging 351

Central nervous system infection (4%), cerebrospinal-fluid fistula (2%), chiasmal compression syndrome (2%), and endocrine syndrome (2%) were other pathological entities

Neurocysticercosis is a parasitic disease that has been diagnosed not only in some developing countries, where it is considered endemic, but also in developed countries, where it is experiencing a continuous increase. The cause of this increase is an ever growing migrant population towards many countries of **N**orthamerica, Europe, etc. Many series of cases of neurocysticercosis highlight the role for endoscopy in order to achieve two main purposes: to diagnose with precision in cases of intracranial and intraspinal cysts where no scolex has been observed with image studies, and to establish a treatment protocol for different pathological entities related to the parasite, such as hidrocephalus, associated with different degrees of ventricular/cisternal inflammatory lesions, as well as its appropriate timing. According to our observations, individual therapeutic measures may be indicated for different time spans in regard to cysticercal disease. The removal of the cyst may be only a limited part of the treatment when dealing with a complex case, in which other anti-cystciercal measures have failed. In such cases, different treatment modalities may be included simultaneously, given the

Cysticercosis cases have presented in our hospitals with many clinical manifestations, such as raised intracranial pressure due to mass effect and/or hypertensive hydrocephalus, meningitis, stroke, dementia, epilepsy, etc. It is not uncommon to include in the treatment protocol several drugs, such as one or more antiepileptics, analgesics, immune depressors, gastric protectors, antibiotics, anticysticercals, etc. Moreover, the treatment modalities include one or more surgical operations which may commonly include endoscopic

extensive clinico-pathological polymorphism of this disease.

procedures that the neurosurgeon must be ready to perform.

Fig. 1. Vascularised capsule from cyst containing live cysticerci.

encountered in the series.


\*Diagnosis and findings of second endoscopy.

**RICP**: Raised Intracranial Pressure. **SD**: Shunt dysfunction. **CSF**: Cerebrospinal Fluid. **M**: Male. **F**: Female.

Table 1. Endoscopy Cases Characteristics.

Among our cases, 72% have been admitted with raised intracranial pressure. Most of these consisted of hypertensive hydrocephalus, although some were diagnosed as intracranial haematomas, cystic tumours with no hydrocephalus, arachnoid and cysticercal cysts, and other diagnosis. All of them but a few were resolved with endoscopic procedures, including drainage, resection and fenestration.

Focal neurological dysfunction was the second syndromic diagnosis which was associated with brain infarcts, visual or other cranial nerve impairment. Some of these cases shared other syndromes such as raised intracranial pressure, meningismus, etc., since these diagnoses were not exclusive.

Dementia was associated with 14% of the cases explored with endoscopy. Not attributed to raised intracranial pressure, necessarily, although shared by this syndrome was a constant feature. Many of these patients were diagnosed as Hakim syndromes and had some improvement of the dementia component after endoscopic exploration and subsequent shunting.

Seizures as an epileptic entity or an isolated event was present in 13% of the cases studied. In some patients epileptic fits were an integral part of the disease, especially in those which were operated on for seizure control under endoscopical supervision. Such cases have been subject to other publications (2) nevertheless it is worth stressing that endoscope-assisted procedures in open neurosurgeries for patients with pharmacological deficient control, have made substantial contributions to the success in the treatment of those patients.

Communicating hydrocephalus

Three ventricle hydrocephalus

hydrocephalus

defect with encephalocele

tumour

hydrocephalus due to intraventricular firm

**RICP**: Raised Intracranial Pressure. **SD**: Shunt dysfunction. **CSF**: Cerebrospinal Fluid. **M**: Male. **F**:

Among our cases, 72% have been admitted with raised intracranial pressure. Most of these consisted of hypertensive hydrocephalus, although some were diagnosed as intracranial haematomas, cystic tumours with no hydrocephalus, arachnoid and cysticercal cysts, and other diagnosis. All of them but a few were resolved with endoscopic procedures, including

Focal neurological dysfunction was the second syndromic diagnosis which was associated with brain infarcts, visual or other cranial nerve impairment. Some of these cases shared other syndromes such as raised intracranial pressure, meningismus, etc., since these

Dementia was associated with 14% of the cases explored with endoscopy. Not attributed to raised intracranial pressure, necessarily, although shared by this syndrome was a constant feature. Many of these patients were diagnosed as Hakim syndromes and had some improvement of the dementia component after endoscopic exploration and subsequent

Seizures as an epileptic entity or an isolated event was present in 13% of the cases studied. In some patients epileptic fits were an integral part of the disease, especially in those which were operated on for seizure control under endoscopical supervision. Such cases have been subject to other publications (2) nevertheless it is worth stressing that endoscope-assisted procedures in open neurosurgeries for patients with pharmacological deficient control, have

made substantial contributions to the success in the treatment of those patients.

**Diagnosis Image Diagnosis Endoscopic Diagnosis Ct/Endo** 

**Correl** 

NO/ NO

NO YES

YES YES

Ventriculomegaly YES NO

The same YES NO

Ventriculomegally. Cysticercal resection in basal cistern. Widespread ependymitis on a second operation.

Right lateral

blocking by ependymal lining

Soft bloody intraventricular

tumour

ventriculomegally due to Monroe foramen

**Tx Modif** 

YES/ NO

**Case Age Sex Clinical** 

dementia

dementia

**103 24 F** RICP Right lateral ventricle

**104 46 F** CSF fistula Right frontal floor

**105 28 M** RICP Universal

\*Diagnosis and findings of second endoscopy.

Table 1. Endoscopy Cases Characteristics.

drainage, resection and fenestration.

diagnoses were not exclusive.

Female.

shunting.

**101 70 M** RICP,

**102 82 M** RICP,

Central nervous system infection (4%), cerebrospinal-fluid fistula (2%), chiasmal compression syndrome (2%), and endocrine syndrome (2%) were other pathological entities encountered in the series.

Neurocysticercosis is a parasitic disease that has been diagnosed not only in some developing countries, where it is considered endemic, but also in developed countries, where it is experiencing a continuous increase. The cause of this increase is an ever growing migrant population towards many countries of **N**orthamerica, Europe, etc. Many series of cases of neurocysticercosis highlight the role for endoscopy in order to achieve two main purposes: to diagnose with precision in cases of intracranial and intraspinal cysts where no scolex has been observed with image studies, and to establish a treatment protocol for different pathological entities related to the parasite, such as hidrocephalus, associated with different degrees of ventricular/cisternal inflammatory lesions, as well as its appropriate timing. According to our observations, individual therapeutic measures may be indicated for different time spans in regard to cysticercal disease. The removal of the cyst may be only a limited part of the treatment when dealing with a complex case, in which other anti-cystciercal measures have failed. In such cases, different treatment modalities may be included simultaneously, given the extensive clinico-pathological polymorphism of this disease.

Cysticercosis cases have presented in our hospitals with many clinical manifestations, such as raised intracranial pressure due to mass effect and/or hypertensive hydrocephalus, meningitis, stroke, dementia, epilepsy, etc. It is not uncommon to include in the treatment protocol several drugs, such as one or more antiepileptics, analgesics, immune depressors, gastric protectors, antibiotics, anticysticercals, etc. Moreover, the treatment modalities include one or more surgical operations which may commonly include endoscopic procedures that the neurosurgeon must be ready to perform.

Fig. 1. Vascularised capsule from cyst containing live cysticerci.

Endoscopic Intracranial Imaging 353

Fig. 4. Firmly adhered capsule to pericystic blood vessels in a case of an arachnoid cyst in

Fig. 5. Colloid cyst capsule involvement of the choroid plexus and foramen of Monroe. Wall characteristics resemble closely those of an aracnoid cyst in vascularity, firm consistency and

the left Sylvian fissure.

piercing resistance.

Fig. 2. Intracapsular view of the viable cysticerci and the characteristics of the highy vascularised capsule wall.

Fig. 3. Intracapsular communication with the ventricular catheter from the shunt system.

Fig. 2. Intracapsular view of the viable cysticerci and the characteristics of the highy

Fig. 3. Intracapsular communication with the ventricular catheter from the shunt system.

vascularised capsule wall.

Fig. 4. Firmly adhered capsule to pericystic blood vessels in a case of an arachnoid cyst in the left Sylvian fissure.

Fig. 5. Colloid cyst capsule involvement of the choroid plexus and foramen of Monroe. Wall characteristics resemble closely those of an aracnoid cyst in vascularity, firm consistency and piercing resistance.

Endoscopic Intracranial Imaging 355

exploration before electrode implantation during epilepsy surgery (3). Among our cases, an endoscopical exploration of the temporal horn of the lateral ventricle was explored previous to electrode placement for resective epilepsy surgery in three patients. In another 2 patients, the endoscope was used to assess the extent of the callosal section. There were no complications derived from these procedures which take only several additional minutes in the operating period. Other authors have inserted electrodes within the ventricles for the

Fig. 6. Visceral cyst wall in a case of cystic astrocytoma. Large vessels organized in several

leyers with different depths, occasionally with varicous formations.

same purpose, and their conclusions are similar to ours (5).

As opposed with some centers in which complicated patients are sent home to meet their fate, all the patients in our hospitals receive some kind of treatment, regardless of their condition. Cases of so called malignant cysticercosis are treated with all the therapeutic resources at hand, with an aggressive treatment that matches the malignancy of the disease.

Some unusual cases of neurocysticercosis have been described previously (7). Although some cases may be considered as coincidences, others may be pathological enigmas. One of these latter cases is a patient who was initially diagnosed as having an interhemispheric arachnoid cyst. During endoscopic exploration, a cyst with a highly vascularised hard capsule was encountered. After several perforations were made, a transparent yellow fluid escaped from the interior of the cyst and several viable cysticerci were also found. The parasites and several blood clots adhered to de walls of the cyst were then removed and finally the cyst was communicated with the ventricluar system where a functional shunt system was previously installed (figures 1-3). After a thorough search in the literature, cyst formations in the subarachnoid space that surrounded live cysticerci have not been previously described. The capsule was similar in resistance, vascularity, and rigidity to those found in other cystic lesions, like arachnoid and colloid cysts (figures 4-5). This could mean that cystcerci may also colonize arachnoid cysts or, on the other hand, they may form a capsule quite similar to that of a congenital condition.

Although few endoscopically accessible tumours can be resected completely, biopsies of larger and more vascularised lesions can be taken with precision from selected areas, considering the amount vascular proliferation, its location and associated phenomena. Because of blurring of the entire field, which may be time-consuming to clear and sometimes difficult to achieve, a bloody fluid-filled space is a major drawback during the tumour resection. Among the tumour type that have been reported to complete or almost complete resection, colloid cysts, some astrocytomas, subependymomas, third ventricle craniopharingiomas, etc, may be mentioned. Hydrocephalus, if present, can be treated during the same exploratory procedure.

Our experience with endoscopy in tumour cases has included 19 cases. Biopsies have been performed in 11 cases while resections have been accomplished in 8. Some of the tumour types include meningiomas and craniopharingiomas within the third ventricle, exophytic gliomas, cystic astrocytomas and carcinomas. Although some intracranial lesions don't have a neoplastic nature strictly speaking, colloid, porencephalic, and arachnoid cysts may also be included in this section because of its commonly associated mass effect.

Endoscopic views from the tumour capsule and surface may have a characteristic appearance when its fluid is clear or has been washed with physiologic solution. There is usually a vascular mesh composed of layers of nets imposed one on top of the other, as onion skins. The vascular proliferation as observed with endoscopy vary according to the tumour type, and it is most abundant as more malignant the tumour is (figs 6-7).

Endoscopic assistance in open cranial neurosurgery has been described for several years, according to the articles written by Perneczky and coworkers, among others (4). Indications of endoscopy related to this modality have also increased, and ongoing publications of new indications are constantly appearing in the words neurosurgical literature. It is frequently used to reach spaces that are normally difficult to observe with the microscope, making the surgical procedure safer. Aneurysm clipping, cranial nerve dissection, are some among many the operations that may normally be assisted with endoscopes.

New indications for endoscopy imaging have been appearing continuously, not only to obtain a precise diagnosis, but also to assist in open surgical procedures. It is now possible to measure the extent of callosal section with endoscopy assistance, as well as ventricular

As opposed with some centers in which complicated patients are sent home to meet their fate, all the patients in our hospitals receive some kind of treatment, regardless of their condition. Cases of so called malignant cysticercosis are treated with all the therapeutic resources at hand, with an aggressive treatment that matches the malignancy of the disease. Some unusual cases of neurocysticercosis have been described previously (7). Although some cases may be considered as coincidences, others may be pathological enigmas. One of these latter cases is a patient who was initially diagnosed as having an interhemispheric arachnoid cyst. During endoscopic exploration, a cyst with a highly vascularised hard capsule was encountered. After several perforations were made, a transparent yellow fluid escaped from the interior of the cyst and several viable cysticerci were also found. The parasites and several blood clots adhered to de walls of the cyst were then removed and finally the cyst was communicated with the ventricluar system where a functional shunt system was previously installed (figures 1-3). After a thorough search in the literature, cyst formations in the subarachnoid space that surrounded live cysticerci have not been previously described. The capsule was similar in resistance, vascularity, and rigidity to those found in other cystic lesions, like arachnoid and colloid cysts (figures 4-5). This could mean that cystcerci may also colonize arachnoid cysts or, on the other hand, they may form

Although few endoscopically accessible tumours can be resected completely, biopsies of larger and more vascularised lesions can be taken with precision from selected areas, considering the amount vascular proliferation, its location and associated phenomena. Because of blurring of the entire field, which may be time-consuming to clear and sometimes difficult to achieve, a bloody fluid-filled space is a major drawback during the tumour resection. Among the tumour type that have been reported to complete or almost complete resection, colloid cysts, some astrocytomas, subependymomas, third ventricle craniopharingiomas, etc, may be mentioned.

Our experience with endoscopy in tumour cases has included 19 cases. Biopsies have been performed in 11 cases while resections have been accomplished in 8. Some of the tumour types include meningiomas and craniopharingiomas within the third ventricle, exophytic gliomas, cystic astrocytomas and carcinomas. Although some intracranial lesions don't have a neoplastic nature strictly speaking, colloid, porencephalic, and arachnoid cysts may also

Endoscopic views from the tumour capsule and surface may have a characteristic appearance when its fluid is clear or has been washed with physiologic solution. There is usually a vascular mesh composed of layers of nets imposed one on top of the other, as onion skins. The vascular proliferation as observed with endoscopy vary according to the

Endoscopic assistance in open cranial neurosurgery has been described for several years, according to the articles written by Perneczky and coworkers, among others (4). Indications of endoscopy related to this modality have also increased, and ongoing publications of new indications are constantly appearing in the words neurosurgical literature. It is frequently used to reach spaces that are normally difficult to observe with the microscope, making the surgical procedure safer. Aneurysm clipping, cranial nerve dissection, are some among

New indications for endoscopy imaging have been appearing continuously, not only to obtain a precise diagnosis, but also to assist in open surgical procedures. It is now possible to measure the extent of callosal section with endoscopy assistance, as well as ventricular

Hydrocephalus, if present, can be treated during the same exploratory procedure.

be included in this section because of its commonly associated mass effect.

many the operations that may normally be assisted with endoscopes.

tumour type, and it is most abundant as more malignant the tumour is (figs 6-7).

a capsule quite similar to that of a congenital condition.

exploration before electrode implantation during epilepsy surgery (3). Among our cases, an endoscopical exploration of the temporal horn of the lateral ventricle was explored previous to electrode placement for resective epilepsy surgery in three patients. In another 2 patients, the endoscope was used to assess the extent of the callosal section. There were no complications derived from these procedures which take only several additional minutes in the operating period. Other authors have inserted electrodes within the ventricles for the same purpose, and their conclusions are similar to ours (5).

Fig. 6. Visceral cyst wall in a case of cystic astrocytoma. Large vessels organized in several leyers with different depths, occasionally with varicous formations.

Endoscopic Intracranial Imaging 357

Postoperative complications after the use of endoscopical equipments are very rare, owing to the minimally-invasive nature of the procedure and the relative ease which the equipment may be handled. Some of these complications reported in the literature have been cases of infections, haemorrhages, or additional cerebral lesions caused by the surgeon; raised intracranial pressure during the procedure caused by defective fluid drainage-related at the time of endoscopy, which may account for neurological deterioration and death, has

Among our cases, the complications that have been observed were accidental punctures to the ventricle walls and lacerations to the borders of the foramen of Monroe. These lesions have apparently been clinically silent. Unsuccessful endoscopical procedures may sometimes be considered as surgical complications, considering the cerebral laceration that is necessary to have access to the ventricles. Taking into account those cases, we would have a higher rate of complications, especially in early procedures when the endoscopic

Although not described by other authors, and even denied by some (6), the endoscopic findings encountered during a second procedure in patients with persistent hydrocephalus following cyticercal resection, have consisted of different types of inflammatory lesions. Because the release of the cyst content has been the probable cause for such inflammatory lesions, these findings that appear in the postoperative period, may be considered by some as complications. Four patients diagnosed as persistent cysticercal hydrocephalus, in which we have performed a second endoscopical observation, could then have increased our

Technological progress has included endoscopy as well as other similar procedures that may be yield similar images, like virtual endoscopy. Until now the special lenses-based Hopkins system images may be superior compared to those obtained through a pixel-based computer reconstruction, although digital technology may be superior to optic technology at

[1] Chrastina J, Novak Z, Riha I. (2080) Neuroendoscopy. Brastisl Lek Listy. 109 (5): 198-201. [2] Jimenez-Vazquez OH, Nagore N. (2008) The impact of neuroendoscopy in the

[4] Perneczky A, Fries G. Endoscope-assited brain surgery: part 1. Evolution, basic concepts,

[5] Song JK, Abou-Khalil B, Konrad PE. Intraventricular monitoring for temporal lobe

[6] Cappabianca P. Application of neuroendoscopy to intraventricular lesions. (2008)

surgical outcome in 55 patients. Clin Neurol Neurosurg 110: 539-543. [3] Jimenez O, Leal R, Nagore N. (2002) Minimally invasive electrodiagnostic monitoring in

epilepsy surgery. Brit J Neurosurg 16 (5): 498-500.

Neurosurgery 62[shc suppl 2]:shc575–shc598.

Neurosurg Psychiatry. 74: 561-5.

and current technique. (1998) Neurosurg 42: 219-224.

emergency setting-a retrospective study of imaging, intraoperative findings, and

epilepsy: report on technique and initial results in eight patients. (2003) J Nneurol

become a recent concern that was largely ignored in the past.

equipments were more modest.

complication rate.

some point.

**2. References** 

HIV-associated hydrocephalus has been explored endoscopically in three patients. Clinically, they have been diagnosed following a continuously deteriorating and waisting condition that suddenly involved the central nervous system. Other common clinical data, like diarrhea, weight loss, cutaneous lesions, etc. were present at the time of hydrocephalus diagnosis. CT scans demonstrated obstructive hydrocephalus with a variable degree of inflammatory ependymal reaction which was confirmed with endoscopical observations. Grayish-white exudates in the ependymal lining, pseudo-membrane formation, inflammatory bands, etc. and other lesions that blocked the cerebro-spinal fluid drainage systems, like the foramen of Monroe and the cerebral aqueduct, were constant findings. Similar to the tuberculous leptomeningitis, the clinical course in these patients was a progressive deterioration regardless of the pharmacological and surgical treatments.

Fig. 7. Dense proliferation resembling a multi-leyer vascular mesh in a case of cystic carcinoma. Opaque yellow fluid has been removed and substituted with saline solution.

HIV-associated hydrocephalus has been explored endoscopically in three patients. Clinically, they have been diagnosed following a continuously deteriorating and waisting condition that suddenly involved the central nervous system. Other common clinical data, like diarrhea, weight loss, cutaneous lesions, etc. were present at the time of hydrocephalus diagnosis. CT scans demonstrated obstructive hydrocephalus with a variable degree of inflammatory ependymal reaction which was confirmed with endoscopical observations. Grayish-white exudates in the ependymal lining, pseudo-membrane formation, inflammatory bands, etc. and other lesions that blocked the cerebro-spinal fluid drainage systems, like the foramen of Monroe and the cerebral aqueduct, were constant findings. Similar to the tuberculous leptomeningitis, the clinical course in these patients was a

progressive deterioration regardless of the pharmacological and surgical treatments.

Fig. 7. Dense proliferation resembling a multi-leyer vascular mesh in a case of cystic carcinoma. Opaque yellow fluid has been removed and substituted with saline solution. Postoperative complications after the use of endoscopical equipments are very rare, owing to the minimally-invasive nature of the procedure and the relative ease which the equipment may be handled. Some of these complications reported in the literature have been cases of infections, haemorrhages, or additional cerebral lesions caused by the surgeon; raised intracranial pressure during the procedure caused by defective fluid drainage-related at the time of endoscopy, which may account for neurological deterioration and death, has become a recent concern that was largely ignored in the past.

Among our cases, the complications that have been observed were accidental punctures to the ventricle walls and lacerations to the borders of the foramen of Monroe. These lesions have apparently been clinically silent. Unsuccessful endoscopical procedures may sometimes be considered as surgical complications, considering the cerebral laceration that is necessary to have access to the ventricles. Taking into account those cases, we would have a higher rate of complications, especially in early procedures when the endoscopic equipments were more modest.

Although not described by other authors, and even denied by some (6), the endoscopic findings encountered during a second procedure in patients with persistent hydrocephalus following cyticercal resection, have consisted of different types of inflammatory lesions. Because the release of the cyst content has been the probable cause for such inflammatory lesions, these findings that appear in the postoperative period, may be considered by some as complications. Four patients diagnosed as persistent cysticercal hydrocephalus, in which we have performed a second endoscopical observation, could then have increased our complication rate.

Technological progress has included endoscopy as well as other similar procedures that may be yield similar images, like virtual endoscopy. Until now the special lenses-based Hopkins system images may be superior compared to those obtained through a pixel-based computer reconstruction, although digital technology may be superior to optic technology at some point.

### **2. References**


[7] Jimenez O, Nagore N. (2000) Cystic lesions associated with meningiomas. Report of three cases. Br J Neurosurg 14(6): 595-596.

[7] Jimenez O, Nagore N. (2000) Cystic lesions associated with meningiomas. Report of

three cases. Br J Neurosurg 14(6): 595-596.

## *Edited by Peter Bright*

Neuroimaging methodologies continue to develop at a remarkable rate, providing ever more sophisticated techniques for investigating brain structure and function. The scope of this book is not to provide a comprehensive overview of methods and applications but to provide a 'snapshot' of current approaches using well established and newly emerging techniques. Taken together, these chapters provide a broad sense of how the limits of what is achievable with neuroimaging methods are being stretched.

Neuroimaging - Methods

Neuroimaging

Methods

*Edited by Peter Bright*

Photo by Rost-9D / iStock