**7. Testing**

**5. Objective symptoms**

426 Glaucoma - Basic and Clinical Aspects

secondary improvement of near vision [38].

Myopic shift in refraction related to the anterior dislocation of the iris-lens diaphragm with

Narrowing or shallowing of the circumferential and central part of the anterior chamber even if patent iridotomy or iridectomy is present. Shallowing of the anterior chamber is related to ante‐ rior dislocation of the iris-lens diaphragm [39,40] and iris-hyaloid diaphragm with coexistence of increased IOP [40]. Persistent symptoms of malignant glaucoma lead to the formation of in‐ tensified anterior adhesions due to the long-lasting shallowing of the anterior chamber [41].

**Figure 2.** Axial shallowing of the anterior chamber in an eye with malignant glaucoma.

Reaction to surgical treatment of the vitreous body [6].

**6. Differential diagnosis**

No decrease of IOP in response to conventional antiglaucoma treatment [4].

Increased IOP – intraocular pressure may increase slowly with simultaneously intensifying shallowing of the anterior chamber [42]. It is characteristic that in the presence of an active, well functioning filtering bleb, the increase in intraocular pressure can be moderate [43].

In many cases, a decrease of IOP or curing as a result of mydriatic-cycloplegic therapy [44].

Glaucoma with pupillary block – pupillary block angle closure occurs when the posterior surface of the iris, in the pupillary margin, comes in contact with the lens. The increased pu‐ pillary block obstructs the flow of the aqueous humour from the posterior chamber to the

Medical history – determination of predisposing factors and early statement of symptoms accompanying the occurrence of malignant glaucoma

Slit lamp examination – assessment of the depth of the anterior chamber shows that there is axial (central and peripheral) shallowing of the anterior chamber and, unlike in pupil block, the iris is not typically bowed forwards, and anterior lens movement is noted. Patency of the iridotomy, if such exists, should be evaluated – if there is no iridotomy or the patency is in doubt, laser iridotomy can be performed or repeated to rule out pupil block, but it does not cause resolution of the condition. Seidel test should be performed to exclude filtering bleb leaking after filtration surgery. Biomicroscopy assessment of the posterior segment is neces‐ sary for the purpose of ruling out choroidal detachment or suprachoroidal hemorrhage

depth during the acute malignant glaucoma phase and an increase of ACA and AOD quan‐ titative values after effective treatment of this condition. It is helpful to objectively evaluate the structures of the anterior chamber or to monitor changes in the anterior segment after surgery. Since the presence of corneal oedema is an indication of prompt surgical interven‐

Malignant Glaucoma

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http://dx.doi.org/10.5772/53979

The goal of conservative treatment is to decrease the production of aqueous humour and shrink the vitreous while simultaneously decreasing resistance in the path of aqueous hu‐

The active mechanism of the drugs used in the treatment of malignant glaucoma is as fol‐

**Mydriatics – cycloplegics** – paralysis of the ciliary muscle, widening of the ciliary processes

**Osmotically active agents** – increase of blood osmolality causing movement of water from the eyeball in the direction of hyperosmotic plasma, which results in a decrease of the hy‐ dration of the vitreous body and makes it possible to retract the iris-lens diaphragm and

**β-blockers** – suppression of aqueous humour production, as a result of which the volume of

**Carbonic anhydrase inhibitors** – reduction of secretion of aqueous humour by inhibiting

**Corticosteroids** – by limiting inflammation, they reduce edema in the area of the ciliary body and help to minimize inflammatory adhesions of the lens or vitreous body with the

According to data from the literature, approximately 50% of patients react to medical thera‐ py [3]. In the work of Debrouwere et al., however, the percentage of recurrences after con‐ servative treatment of patients with malignant glaucoma was equal to 100%, despite an initially good response to such therapy [49]. Also, in own experience, a lack of success in re‐ versing the pathogenic mechanism by means of conservative treatment in malignant glauco‐ ma concerns the great majority of cases. In own material, reactions to conservative treatment were observed in 5 eyes with malignant glaucoma out of 22 of those tested [22.7%), howev‐ er, ultimately, a surgical procedure was necessary in three of them due to the recurrence of typical symptoms and no control over IOP. Permanent improvement after pharmacological treatment was achieved in only 2 eyes [9.1%). The observations of other authors also confirm transient effectiveness of medical therapy during the initial period [11,42]. Even if IOP con‐

tion it can be used to assess this parameter in a non-contact fashion [40].

mour flow to the anterior chamber through applied cycloplegia.

ring, tightening of the zonule apparatus, backwards movement of the lens.

**8. Treatment**

lows:

**8.1. Conservative treatment**

deepen the anterior chamber.

ciliary body [20].

humour directed towards the vitreous is reduced.

carbonic anhydrase activity in the epithelium of the ciliary body.

Tonometry – usually reveals increased IOP

Ultrasonography – conducted for the purpose of determining the axial length of the eyeball (which tends to be shorter than normal) and to determine the position and size of the ciliary body and its processes [25]. Moreover, information on the thickness of the choroid may be obtained through ultrasonographic examination

Ultrabiomicroscopy (UBM) – this test gives images of the iris, the intraocular lens and ciliary body as well as their relative positions before and after the occurrence of malignant glauco‐ ma. The rotation of the ciliary body to the front and shallowing of the anterior chamber may be subject to normalization after tearing of the anterior hyaloid [24]. This test enables visual‐ ization of the structures of the anterior segment, although the capability of conducting tests in the early postoperative period is limited due to the immersion technique

**Figure 3.** OCT of the anterior segment in malignant glaucoma – shallowing of the anterior chamber, peripheral irido‐ corneal touch, forward shift of the IOL.

Anterior segment OCT *(optical coherence tomography)* – a non-invasive high resolution techni‐ que that can be used for the purpose of objective imaging of the iridocorneal angle structure as well as for qualitiative and quantitative assessment. Parameters such as: AOD – *anterior chamber opening distance,* ACA – *anterior chamber angle* have been adapted from ultrasound biomicroscopy for the OCT method. Measurements of scleral thickness, CCT – *central corneal thickness*, and central depth of the anterior chamber during an episode of malignant glauco‐ ma can also be conducted. Marked displacement of the structures of the anterior segment, peripheral irido-corneal touch, and forward shift of the lens may be noted Examination may reveal a decreased anterior chamber angle with extreme shallowing of the anterior chamber depth during the acute malignant glaucoma phase and an increase of ACA and AOD quan‐ titative values after effective treatment of this condition. It is helpful to objectively evaluate the structures of the anterior chamber or to monitor changes in the anterior segment after surgery. Since the presence of corneal oedema is an indication of prompt surgical interven‐ tion it can be used to assess this parameter in a non-contact fashion [40].
