Ординатура / Офтальмология / Английские материалы / Atlas of Glaucoma, Second Edition_Choplin, Lundy_2007

Figure 11.10 Anatomy following laser iridotomy, UBM. Following iridotomy, the angle in the patient shown in Figure 11.7 has opened. Note the increase in iris–lens contact, as aqueous now bypasses the pupillary space and flows through the iridotomy.

Figure 11.11 Pseudophakic pupillary block, UBM. An alteration in the relationship between the anterior surface of the posterior chamber intraocular lens and iris occurs following laser iridotomy for pseudophakic pupillary block. In pseudophakic pupillary block, aqueous flows between the posterior chamber intraocular lens and the iris into the anterior chamber and may lift the iris off the surface of the lens.

Figure 11.12 Laser iridotomy for pseudophakic pupillary block, UBM. Following laser iridotomy in the eyes shown in Figure 11.11, the iris moves posteriorly against the intraocular lens as aqueous bypasses the pupil, flows through the iridotomy, and allows the iris to flatten.

Figure 11.13 Chronic angle closure with synechiae, UBM.

Following laser iridotomy for pupillary block–angle-closure glaucoma in this patient, the iris has assumed a flat configuration, consistent with relief of pupillary block, but iridotrabecular apposition persists (arrows), indicating the presence of synechial closure.

Figure 11.14 Dark-room provocation, UBM. When assessing a patient with a narrow angle for occludability, it is important to perform gonioscopy in a completely darkened room, using the smallest square of light for a slit beam, so as to avoid stimulating the pupillary light reflex. This eye is being scanned under normal room illumination. The angle is open.

Figure 11.15 Dark-room provocation, UBM. Under dim illumination, the pupil dilates and the peripheral iris moves into the angle causing appositional angle closure. At least two minutes in total darkness should be allowed for the angle to close before assuming that it is not spontaneously occludable. If the angle closes under these conditions, opening the door of the examination room, turning on the light, or increasing the size of the slit beam will allow the pupil to constrict once again, so that the angle configuration in any quadrant can be compared in a light–dark–light situation.

Figure 11.16 Acute angle-closure glaucoma. Acute angleclosure glaucoma is often characterized by ocular injection, blurred vision, and pain. The pupil is often fixed in a mid-dilated position.

Figure 11.17 Acute angle-closure glaucoma, UBM. During an attack of acute angle closure, the length of iridolenticular contact is typically small, although the resistance to aqueous flow through the pupil is maximal.

Figure 11.18 Anterior chamber angle configuration after laser iridotomy, UBM. Following laser iridotomy, the angle opens if peripheral anterior synechiae are not present. Following laser iridotomy in the patient described in Figure 11.17, the iris remains in contact with the lens surface and assumes its curvilinear contour. The peripheral iris has flattened following the iridotomy.

Figure 11.19 Acute pseudophakic pupillary block. Prior to treatment in this patient with acute pseudophakic pupillary block, the anterior chamber is shallow and the cornea is edematous. The intraocular pressure is 65 mmHg.

Figure 11.20 Acute pseudophakic pupillary block. In this patient with an anterior chamber intraocular lens and pupillary block, the iris surrounding the intraocular lens has assumed a bombé configuration, while the portion of iris immediately posterior to the intraocular lens remains held in its flat position by the implant itself.

Figure 11.21 Pupillary block with posterior chamber intraocular lens, UBM. In this patient with acute pseudophakic pupillary block angle-closure glaucoma, iris bombé is present and the optic is in relatively normal position. The end of the haptic is visible. (Reprinted from Tello C, Chi T, Shepps G, Liebmann J, Ritch R. Ultrasound biomicroscopy in pseudophakic malignant glaucoma. Ophthalmology 1993; 100: 1330–4 (Figure 4a).)

Figure 11.24 Glaukomflecken. Subepithelial lens opacification may occur following acute angle-closure glaucoma and is termed glaukomflecken.

Figure 11.25 Plateau iris syndrome. A large or anteriorly positioned ciliary body can maintain the iris root in proximity to the trabecular meshwork, creating a configuration known as plateau iris.

Figure 11.26 Plateau iris syndrome, UBM. In plateau iris syndrome, the physical presence of an anteriorly placed ciliary body (CB) forces the peripheral iris (I) into the angle. In this patient, iridotomy has relieved the contribution of pupillary block to the angle narrowing (the iris contour is planar in this patient), but not the closure related to the abnormal ciliary body position. The angle in this patient is barely open.

Figure 11.27 Gonioscopy in plateau iris. Gonioscopic appearance of the angle in plateau iris syndrome prior to indentation. (Reprinted from Ritch R, Liebmann JM. Argon laser peripheral iridoplasty. Ophthalmic Surg 1996; 27: 289–300 (Figure 4a).)

Figure 11.28 Indentation gonioscopy in plateau iris. The physical presence of the lens behind the iris plane holds the iris in position and tries to prevent posterior movement of the central iris. As a result, a sinuous configuration results (sigma sign), in which the iris follows the curvature of the lens, reaches its deepest point at the lens equator, then rises again over the ciliary processes before dropping peripherally. Much more force is needed during gonioscopy to open the angle than in pupillary block, because the ciliary processes must be displaced, and the angle does not open as widely. (Reprinted from Ritch R, Liebmann JM. Argon laser peripheral iridoplasty. Ophthalmic Surg 1996; 27: 289–300 (Figure 4b).)

Figure 11.29 Degrees of plateau iris configuration. The extent, or the ‘height’ to which the plateau rises, determines whether or not the angle will close completely or only partially. In the complete plateau iris syndrome, the angle closes to the upper meshwork or Schwalbe’s line, blocking aqueous outflow and leading to a rise in IOP. This situation is far less common than the incomplete syndrome, in which the angle closes only partially, leaving the upper portion of the filtering meshwork open, so that the IOP will not rise. (Reprinted from Lowe RF, Ritch R. Angle-closure glaucoma. Clinical types. In: Ritch R, Shields MB, Krupin T, eds. The Glaucomas, 2nd edn. St Louis: CV Mosby, 1996: 827 (Figure 38-6).)

Figure 11.30 Angle closure in plateau iris, UBM. The angle is closed in this patient with plateau iris syndrome. The iris configuration is planar.

Figure 11.31 Laser iridotomy in plateau iris, UBM. A patent laser iridotomy in the eye shown in Figure 11.30 with plateau iris syndrome and persistent appositional angle closure.

Figure 11.32 Dark-room provocation in plateau iris, UBM.

Provocative testing in eyes with plateau iris configuration should be performed following laser iridotomy. Under normal room illumination, the angle in this patient with plateau configuration is narrow, but open.

Figure 11.33 Dark-room provocation in plateau iris, UBM.

During dark-room provocation and ultrasound scanning, the peripheral iris dilates and appositional angle closure develops.

Figure 11.38 Laser iridoplasty. The key to iridoplasty, which can also be used during an acute attack of angle-closure glaucoma unresponsive to medical therapy, or when iridotomy cannot be safely performed because of hazy media, is correct placement of the laser applications, which, in this patient, has produced a ring of hyperpigmented spots corresponding to the treatment sites. This patient has an inferiorly placed laser iridotomy.

Figure 11.40 Pseudoplateau iris configuration, UBM. Other abnormalities of ciliary body architecture may result in a condition termed pseudoplateau iris. This general term is non-specific and does not differentiate between distinct entities as cyst, tumor, or inflammation. These conditions are usually easily diagnosed, as the angle is closed either in one quadrant or, if cysts are multiple, intermittently. Focal forms of angle closure may be induced by cystic or solid masses involving the iris or the ciliary body. Iridociliary cysts are characterized by an echolucent interior. For example, a pigment epithelial cyst in this patient has caused focal narrowing of the anterior chamber angle in the region of the cyst.

Figure 11.39 Laser iridoplasty. Iridoplasty in this patient was performed incorrectly, and laser application sites are visible in the mid-peripheral iris.

Figure 11.41 Loculated iridociliary cysts, UBM. Pigment epithelial cysts can arise from the pigment epithelium of the iris, the ciliary body, or the junction between them. Iridociliary cysts are the most common form, and some have multiple loculations. The walls of these cysts are indicated (arrows).

Figure 11.42 Ciliary body cyst, UBM. Abnormal embryogenesis can lead to focal angle closure by true cysts of the ciliary body stroma, as is present in this patient. The pigment epithelium is normal and the ciliary body architecture is distorted.

Figure 11.44 Ciliary body tumor. Ciliary body tumor enlargement can occur, owing to anterior segment inflammation, as shown here.

Figure 11.43 Anterior segment tumors, UBM. Primary or metastatic tumors of the iris and/or ciliary body can cause angle closure. This iris tumor is causing mechanical obstruction of the meshwork.

BLOCK AT THE LEVEL OF THE LENS

Figure 11.45 Lens-induced angle-closure. Angle-closure glaucoma may be caused by an anteriorly subluxed, dislocated, intumescent lens. In this schematic, the physical presence of an anteriorly positioned, enlarged lens is causing shallowing of the anterior chamber and angle closure.

Figure 11.48 Laser iridotomy in lens-induced angle closure, UBM. Ultrasound biomicroscopy following laser iridotomy shows the iris to be in contact with the anterior lens surface, mechanically obstructing the angle.

Figure 11.49 Central anterior chamber depth in lens-induced angle closure, UBM. The central anterior chamber is considerably shallower in eyes with lens-induced angle closure than in eyes with angle closure caused by pupillary block or plateau iris syndrome.