**3.1 Insula lobe epilepsy**

#### **3.1.1 Background**

180 Novel Aspects on Epilepsy

With nocturnal frontal lobe epilepsy, seizures begin shortly after falling asleep or in the early hours before awakening with a gasp, grunt, hums, moan or word, and are followed by sudden thrashing movements. Patients remain conscious but can neither control the movements nor speak. Thrashing can be vigorous enough to throw the patient out of bed, which can result in possible injury. Nocturnal frontal lobe epilepsy is typically treated with carbamazepine and, in some cases, surgery. We did not identify this type of seizures in our series. If there is evidence of NC on imagenology then a diagnosis of NFLE is ruled out.

Parietal lobe epilepsy is the least common of syndromes defined by the area of brain affected. Parietal seizures spread rapidly, producing a range of symptoms that are also seen with other syndromes. A few signs are typical but appear in less than half of children who

Patients can present an acute confusional state (delirium) and the commonest affected parts of the body are: upper limbs and face. Partial seizures are divided into two major categories, simple and complex. Simple partial seizures occur in full consciousness; complex partial seizures occur with impaired awareness that ranges from slight to complete

Seizures often begin with auras or conscious feelings of a rising sensation from the

Impaired awareness follows, typically with staring and movements of the lips, tongue or

Remembering the lost island of Atlantis, this lobe remains hidden and lies submerged beneath the parietal, frontal, and temporal opercular cortices, buried under a tangled web of middle cerebral artery branches. The insula is not visible from the surface of the brain, it's the best protected region of the whole cerebral cortex, and the poorest studied region all over the brain; IL represents a remarkable challenge for further researchers among new generations of neurologists, neurophysiologists, neuroinmunologists, and neuropathologist among others. Some functions of the right insular lobe are a little bit known such as its role in taste perception its intensity and recognition for the ipsilateral tongue (rostrodorsal insula) and some functions of the left insular cortex for the intensity of the stimulus ipsilateral to the tongue and taste recognition bilaterally, gustatory mechanism, movements

Tingling, pricking or crawling sensations upon the skin

Pain occurs in the extremities and sometimes in the abdomen

**2.3 Parietal lobe epilepsy** 

have this syndrome. Among the symptoms are:

unconsciousness. (Epileptic Foundation)

**2.4 Mesial temporal lobe epilepsy** 

stomach and of fear

**3. Insular lobe** 

jaw

The feeling of burning, itching or pain

One of the sensory perceptions may also be triggered

Fumbling, picking or gesturing may also occur

Insular lobe epilepsy (ILE) and insular lobe seizures (ILS) are still not included in the current classification for epileptic seizures, epilepsy or epileptic syndromes belong to "The International League Against Epilepsy" therefore most of neurologists, epileptologists, clinician pediatrician, and general practitioner do not include this entity in their list of differential diagnosis in patients presenting "aberrant" types of temporal lobe epilepsy (TLE), "stereotype" simple focal seizures and others. Insular seizures may mimic temporal, parietal or frontal lobe seizures and may coexist with seizures from other lobes.

The electroencephalographic (EEG) studies of the insula lobe (IL) are not confident because it is the only cortical part of the brain that is not accessible at the surface of the cerebral hemisphere, because it is totally covered by the fronto-parietal and temporal opercula, therefore accuracy of EEG made by surface electrode is uncertain.

The insula is one of the five cerebral lobes and its cortex is situated deep within each hemisphere. It is overlayed by the frontal and temporal neocortex and this explains how difficult it should be to get a reliable EEG sampling from the insular cortex and to define an "insular epileptic syndrome" as has been done with temporal lobe epilepsy. Adequate sampling from the insula can only be obtained by depth or subdural electrodes' implantation or acute intraoperative electrocorticography. Depth or subdural electrodes implantation of the insular faces some technical problems. There is substantial evidence that the insula is involved as a somesthetic area, including a major role in the process of nociceptive input. The role of the insula in some epileptic patients was recently investigated by means of depth electrode recordings made following Talairach's stereoelectroencephalography (SEEG) methodology. It appears that ictal signs associated with an insular discharge is very similar to those usually attributed to mesial temporal lobe seizures (Robles et al, 2009]) others authors reported: sensation of laryngeal constriction and paresthesiae, often unpleasant, affecting large cutaneous territories, most often at the onset of a complex partial seizure (five of the six patients) as a common presentation [ Isnard J, et al., 2004] while other said: the most common clinical feature associated with damage to the insula is the complex partial seizures with involvement of the visceral sensations (Duffau H, et al., 2002). Different authors reported ictal symptoms associated with insular discharges mainly made up of respiratory, viscerosensitive (chest or abdominal constriction), or oroalimentary (chewing or swallowing) manifestations. Unpleasant somatosensory manifestation always opposite the discharging side, are also frequent and they concluded that Ictal signs arising from the insula occur in full consciousness; these are always simple

Clinical Features of Epilepsy Secondary to Neurocysticercosis at the Insular Lobe 183

Demographic and clinical data were obtained through interviews with the patients and their

The differences between groups A and B were evaluated for statistical significance with the use of Statistical Package for the Social Sciences version 16.0 for windows (SPSS Inc.,

All patients received 800 mg of albendazole and 40 mg of prednisone per os daily for a week as part of treatment for NC and 200mg of carbamazepine orally every 8 hour to control

All images were acquired on the same CT scan and MR images using a three-dimensional T1-fast field echo sequence providing an isotropic voxel size of 1 mm3. Images underwent correction for no uniform intensity and were linearly registered into a standardized stereotaxic space. The interval between the first and last scan was 31 ± 21 months (range = 10

Terminal diseases, serious psychological illnesses, active addictions to psychoactive

Any event that may lead to a situation that discourages the intervention or that may

Written informed consent was obtained in the first assessment of eligible patients for participation. All patients received information on the study's objective and procedures in addition to ethical considerations, including and the participant's right to intimacy, anonymity, confidentiality, withdrawal, and information. Both investigators completed CITI training-course on the Protection of Human Research and sworn to the Hippocratic Oath and committed to respecting the norms of good clinical practice, as well as the requirements

Patients younger than 13 years old, pregnant ladies, patients on HAART

prevent communication with the healthcare professional.

2.-CT/MRI images of the brain with intravenous contrast or gadolinium enhancement, consistent with definitive evidence of active and calcified NCC on

1.-NC on the temporal lobe and similar age group

3.-Positive serology ELISA test for cysticercosis

4.-ELISA test for HIV/AIDS

the temporal lobe suitable to evaluate: ictal manifestation.

**Group B:** 

relatives.

Chicago, Ill)

to 52).

substances

epileptic seizures.

**3.2.3 Exclusion criteria** 

No written consent.

**3.2.5 Ethical aspects** 

of the Helsinki Declaration.

**3.2.4 Withdrawal criteria** 

Epilepsy due to other causes

partial seizures. Seizures arising from the temporal lobe always invade the insular region, but in approximately 10% of cases, the seizures originate in the insular cortex itself (Isnard, 2004; Guenot, 2008). In 2005, Isnard studied 50 patients using intrainsular electrodes and found that the clinical presentation of insular lobe seizures was a simple partial seizures occurring in full consciousness patient, beginning with a sensation of laryngeal constriction followed by paresthesiae that were often unpleasant affecting large cutaneous territories. These initial symptoms were eventually followed by dysarthric speech and/or elementary auditory hallucinations, and seizures often ended with focal dystonic postures. Four years later he studied 164 patients in whom 472 insular electrodes were implanted, he again found that clinical presentation of insular lobe seizures are that of simple partial seizures occurring in full consciousness, beginning with a sensation of laryngeal constriction followed by paresthesia that were often unpleasant on extensive cutaneous territories. These initial symptoms were eventually followed by dysarthric speech and/or elementary auditory hallucinations, and seizures often ended with focal dystonic postures. He was able to reproduce several of the spontaneous ictal symptoms in the six patients with insular seizures. (Isnard, 2009). Looking into other ways to check clinical features of IL due to focal lesions, we reviewed what happen in patients presenting NC on the IL.

According to the publications made in the last decade, very little is known about NC on the IL (Foyaca-Sibat & Ibañez-Valdés, 2006). It is important to highlight that it is a dangerous location of NC because apart from epilepsy other complications such as: autonomic dysfunction (Oppenheimer et al., 2001), neurogenic heart (Tamayo & Hachinski, 2003), electrocardiographic changes (Blumhardt et al., 1986) and sudden unexpected death in epilepsy [SUDEP] (Leestma, 1984; Mc Gugan, 1999; Langan Y, 2000) can occur

The main aim of our study was to identify ictal manifestations in patients presenting focal lesions (NC) on the IL proved by imagenology. To our knowledge, it is the first time that results from ILE secondary to focal NC in a case-control study are reported in the medical literature.
