Angle Recession, Traumatic

Definition: Angle recession is considered a sequel of blunt eye trauma in which the ciliary muscle is torn between the longitudinal and circular layers. An obtuse anterior chamber angle results from tearing of the ciliary muscle as there is posterior displacement of the iris root. The longitudinal or meridional ciliary muscle remains attached. (Click here for a review of ciliary muscle anatomy). This distinguishes recession from cyclodialysis, where the entire ciliary body including the longitudinal muscle is detached.
Incidence/ Prevalence: A gonioscopic survey in a South African town, revealed recession in about 15% of people. (Ref. 1) The majority showed bilateral angle recession. Recession was more common in men. 5.5% of patients with angle recession had glaucoma. In patients with 360 degrees of angle recession, 8.0% had glaucoma. Excessive alcohol consumption was significantly related to the presence of angle recession in women. The prevalence of monocular blindness due to trauma was 2.5%.
Etiology: Angle recession is caused by significant blunt trauma. In our experience it is common in boxers. The initial injury is often accompanied by hyphema, so that patient who present with hyphema must be followed for later development of angle recession and glaucoma.
Clinical Findings: On gonioscopy, the ciliary body band is increased in size and irregularly widened. OCT has been recommended to give a 3D image of the recessed angle and more accurately determine the extent without putting pressure on the anterior segment.(Ref. 2).
Gross pathology: The diagnosis of angle recession can be subtle because of anatomic variations of the angle. Yanoff suggests a diagnostic method in sections of the eye that involves drawing a line through the optic axis (pink arrowed line in diagram) and then drawing a second line (yellow arrowed lines in picture) parallel to the first but which includes the scleral spur. If the angle recess is located posteriorly to the line (as the white arrow indicates) then there is angle recession.
Under gross dissection the normal wedge of the ciliary body is effaced as the ciliary body is stripped from the sclera and moves interiorly. While an unaffected angle has a wedge with the presenting base of the ciliary body anteriorly, the concussive angle deformity shows a fusiform shape of the ciliary body anteriorly. There is a greater area of the ciliary body that is exposed anteriorly. The iris root and pars plicata are displaced posteriorly. There may be fibrous tissue in ciliary body.
Histopathology: The same principles seen in the gross examination apply to histologic sections for diagnosis. The relationship of the sclera spur (arrow #1) reveals the posterior displacement of the iris-ciliary body complex. Residual meridional ciliary muscle strands are seen attached to the sclera (arrow #2). The effaced ciliary muscle shows pigment as it is reflected posteriorly (arrow #3). Angle injury to the outflow tract is indicated by pigment laden macrophages and fibrosis over the trabecular meshwork (arrow 4). The remaining attached longitudinal ciliary muscle is evident at arrow # 5. Circular muscle fibers are seen at arrow #6. Radial ciliary muscle fibers are evident at arrow #7. Secondary complications of angle recession include obstruction of the trabecular meshwork by synechiae or endothelialization over the trabecular meshwork. The synechiae are sequelae of inflammation and hemorrhage. Endothelialization may reflect injury to the cornea. The final result is glaucoma, which if untreated may result in glaucomatous atrophy (see image below).


Treatment: The glaucoma is treated as open angle glaucoma. Some have indicated that trabeculectomy with antimetabolite therapy is more effective than other surgical treatment in these patients. (Ref. 3)
Prognosis: About 6% of patients develop glaucoma after angle recession from the mechanisms of trabecular meshwork obstruction described above. Additional mechanisms include damage and scarring to the outflow apparatus, cataract and phacolytic glaucoma.

References:
1. Salmond JF et al. The detection of post-traumatic angle recession by gonioscopy in a population-base glaucoma survey. Ophthalmology 1994.
2. Keisuke Kawana, Yoshiaki Yasuno, Toyohiko Yatagai, Tetsuro Oshika (2007) High-speed, swept-source optical coherence tomography: a 3-dimensional view of anterior chamber angle recession Acta Ophthalmologica Scandinavica 85 (6) , 684–685
3. Mermoud et al. Ophthalmology 1993.

Phacolytic Glaucoma

PHACOLYTIC REACTIONS
Definition: Phacolytic glaucoma was originally defined as open-angle glaucoma associated with hypermature cataract.

History: Phacolytic glaucoma was coined in 1955 by Flocks et al. [1].

Etiology: Phacolytic glaucoma is produced by blockage of aqueous outflow by both soluble lens protein and macrophages (as part of the inflammatory response) that obstruct the trabecular meshwork. [2][3]
Incidence/Prevalence: This disorder has markedly decreased in incidence in the U.S. because of earlier cataract extraction. In a large series in India 115 cases of phacolytic glaucoma were reported from 27,073 patients with cataract.[3].

Clinical Findings: Most patients present with pain, a red eye, elevated intraocular pressure, and of course chronic visual loss. The protein and cells will be visualized in the anterior chamber.

Histopathology: The proteinaceous material and macrophage accumulate in the angle structures and trabecular meshwork (arrow 1). Macrophages can be found on the anterior (arrow 2) and posterior (arrow 3) surface of the iris, around the lens capsule and lens zonule, (arrow 4), along the inner surface of the retina, and on the optic nerve head. The lens may appear shrunken with loss of nuclear and cortical material and the lens capsule may appear collapsed (arrows 5).

Treatment: Cataract removal and irrigation of the anterior chamber with removal of lens proteins has been very effective. If the disorder is not promptly recognized and treated, the visual prognosis is generally poor due to optic atrophy, uveitis, and corneal edema. [3] Spontaneous recovery with resorption of lens and resolution of the glaucoma has been reported. [4]
References:
1. Flocks M et al. A clinicopathologic study of 138 cases of glaucoma associated with hypermature cataract. Arch Ophthalmol 1955;54:37-45.
2. Epstein DL et al. Obstruction of aqueous outflow by lens particles and by heavy molecular weight soluble lens protein. Invest Ophthalmol Vis Sci 1978;17:272-277.
3. Pradhan et al. Indian Journal of Ophthalmology 2001;49:204.

4. Blaise et al. J Cataract Refract Surg. 2005;31:1829-30.

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Axenfeld Anomaly and Syndrome

Definition: Axenfeld anomaly, also called posterior embryotoxon, is a congenital anomaly in which Schwalbe’s line (arrow #1) is anteriorly displaced and associated with iris bands that extend to the cornea (arrow #2). If the development of the meshwork is defective and glaucoma is present, the condition is called Axenfeld syndrome. The Rieger anomaly is the term used to describe iris and pupillary abnormalities in combination with the findings of the Axenfeld anomaly. The Reiger anomaly is associated with the later onset of glaucoma. If the Rieger anomaly is associated with dental and skeletal abnormalities, the condition is called the Rieger syndrome.
History: Axenfeld described this abnomality in 1920.
Incidence/Prevalence: 50% of patients with the Axenfeld anomaly have been reported to progress to develop glaucoma.
Etiology: Mutations of the FOXC1 gene and in the PITX2 gene have been described in families with the Axenfeld-Rieger syndrome (1,2).
Clinical Findings: Axenfeld anomaly manifests as a crescentic shaped opacity in the peripheral cornea. Schwalbe’s line is not visible normally, so the presence of this ring is clinically diagnostic. Strands may extend from the iris periphery to the cornea. If the angle structures are normal and there is no glaucoma this is called the Axenfeld anomaly.
Histopathology: Sections show anterior displacement and usually thickening of Schwalbe's line. Schwalbe's line appears in section as a collagenous nubbin (arrow 3 in Figure). Frequently, iris processes extend from the peripheral iris to insert at Schwalbe's line on the cornea (arrow 4). Notice in the photograph that there is a thin Descemet's membrane and endothelium on either side of Schwalbe's line indicating it is abnormally displaced anteriorly and interposed between clear cornea.
Treatment: Trabeculostomy and trabeculectomy have been performed in patients with Axenfeld syndrome.
References:
1. Panicker SG et al. Invest Ophthalmol Vis Sci. 2002; 243:3613-6.
2. Borges AS et al. J Glaucoma. 2002;11:51-6

Pigment Dispersion Syndrome

Definition: Pigment dispersion syndrome is characterized by the deposition of iris pigment on the cornea endothelial surface, trabecular meshwork, anterior iris, lens capsule and lens zonule sometimes in association with glaucoma (½ of cases the cases of pigment disperstion syndrome).
History: Sugar and Barbour described pigment dispersion syndrome in 1949.
Incidence/ Prevalence: Pigment dispersion syndrome is associated with myopia, male gender, begins between the ages of 20-45 years, with a reported prevalence of up about ~2.5% in "whites", a population at risk. Familial cases are rare but are inherited in an autosomal dominant pattern. Glaucoma is present in 50% of the cases.
Etiology: In 1979 the concept was proposed that the iris bowed posteriorly in the midperiphery to rub against zonular fibers releasing pigment from the iris (1). The iris may have an irregular pupillary surface (#1 arrow in figure). The evidence for the zonular friction theory is that the anterior chamber in these patients is unusually deep in the midperiphery and that zonular fibers are found in proximity of the iris radial transillumination slits (# 2 red arrows in the gross photograph of the back of the iris). A reverse pupillary block mechanism has been invoked in which aqueous cannot flow into the posterior chamber because of the lens iris contact. The bowing may be worsened during forward movement of the lens as occurs during accommodation although increases in intraocular pressure and pigment dispersion with acccomodation are more controversial.
Pigment dispersion may be associated with a variety of other conditions in which pigment epithelium or uveal melanocytes are injured, such as uveitis (uveitic glaucoma) or uveal melanoma. These conditions are characterized by pigment within the trabecular meshwork and in macrophages littering the angle. The dispersed pigment is presumed to be iris pigment epithelium mechanically rubbed off by contact with lens zonular fibers.
Clinical Findings: There is a mid peripheral iris transillumination defect, iridonesis pigmentation anterior iris surface. Pigmentation on the posterior corneal surface is called Krukenberg’s spindle. There can be pigmentation of the lens (arrow #3), trabecular meshwork, pars plana.The pigmentation may precede the glaucoma by as much as 20 years.

Gross and Histopathology: Pigment is present on the lens zonule (arrow #4 above). Extracellular pigment becomes trapped in the trabecular meshwork (arrow #5). Scattered pigment may be seen lying on the anterior surface of the iris (arrow #6).Intracellular pigment may be found in macrophages lining the uveal cords and/or in endothelium lining the meshwork. Deposition of pigment tends to be mainly inferior on the cornea (arrow #5). Krukenberg’s spindle manifests histologically as pigment laden endothelial cells (arrow 7).
Treatment: Some believe that laser iridotomy may relieve the reverse pupillary block mechanism and reverse the posterior bowing of the iris. A decrease in pigment granules dispersed after laser has been published (2).
References:
1. Campbell DG. Pigmentary dispersion and glaucoma. A new theory. Arch Ophthalmol. 1979;97:1667-72.
2. Küchle M, Nguyen NX, Mardin CY, Naumann GO. Effect of neodymium:YAG laser iridotomy on number of aqueous melanin granules in primary pigment dispersion syndrome.
Graefes Arch Clin Exp Ophthalmol. 2001; 239:411-5.
3. Ritch R et al. Prevalence of pigment dispersion syndrome in a population undergoing glaucoma screening. AJO 1993:115:707.