Gonioscopy

The angle of the eye is examined by gonioscopy, which requires the use of special lenses. Gonioscopy is performed to rule out angle-closure or secondary causes of lOP elevation, such as angle recession, pigmentary glaucoma, and exfoliation syndrome. The peripheral contour of the iris is examined for plateau iris, and the trabecular meshwork for peripheral anterior synechiae, as well as for neovascular or inflammatory membranes. 

Schlemm s canal may be seen if blood reflnxes into the canal. This might indicate elevated episcleral venons pres-snre cansed by conditions snch as a carotid-cavemons fistnla, Graves orbitopathy, or Stnrge-Weber syndrome. 

Ultrasonnd biomicroscopy is helpfnl in assessing the angle, iris, and ciliary body to rule out anatomical pathology and secondary causes of elevated lOP. 

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Gonioscopy anterior chamber angles will be closed ... 

Gonioscopy Examination of the anterior chamber angle of the eye. A gonioprism or Goldman lens is used to perform gonioscopic evaluation. 

For closed-angle glaucoma, the presence of a narrow angle is usually visualized by gonioscopy. IOP is generally markedly elevated (e.g., 40 to 90 mm Hg) when symptoms are present. Additional signs include hyperemic conjunctiva, cloudy cornea, shallow anterior chamber, and occasionally edematous and hyperemic optic disk. 

Gonioscopy Because pupil dilation may precipitate an acute attack of narrow-angle glaucoma, evaluate anterior chamber angle by gonioscopy prior to beginning therapy. 

Gonioscopy Use only when shorter-acting miotics have proven inadequate. Gonioscopy is recommended prior to use of medication. 

Topical anesthesia is necessary for applanation tonometry and gonioscopy. Proparacaine and benoxinate are most... 

The angle can be assessed by using the shadow test, the sUt-lamp method, or most accurately by gonioscopy. 

Figure 20-5 Major anatomic landmarks in gonioscopy. Schwalbe s line (SL), trabecular meshwork (TM), scleral spur (SS), and ciliary body (CB).

Shaffer RN. Gonioscopy ophthalmoscopy, and perimetry. Trans AmAcad Ophthalmol Otol 1960 64 113-127. 

Gonioscopy, if a shallow anterior chamber is observed or suspected... 

It is important to perform gonioscopy only in recalcitrant cases of intermediate uveitis to rule out complications such as peripheral anterior synechia and neovascularization. Otherwise, this test is superfluous. 

The patient may or may not have symptoms from pupil distortion. Clinically, the pupil and anterior chamber should be eraluated before dilation. If the pupil is peaked at the first postoperative visit, the examiner may carefiilly examine with gonioscopy, looking for vitreous or iris extending to the wound. Presence of vitreous prolapse in the anterior chamber necessitates a thorough retinal eraluation early in the postoperative period, looking for secondary retinal breaks. lOL position and capsule integrity should be eraluated to further define the source of pupil distortion. 

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