PIGMENTARY GLAUCOMA: A CLINICAL REVIEW OF ANTERIOR SEGMENT PIGMENT DISPERSAL SYNDROME

Sixty-eight cases (44 males, 24 females) of anterior segment pigment dispersal syndrome are reviewed. Five patients had no rise in intraocular pressure, 38 had ocular hypertension and 25 had glaucoma as shown by optic disc cupping and field loss. All cases had heavy deposition of pigment in the drainage angle together with Krukenberg spindles and/or light reflux through the iris. Other evidence of anterior segment pigment dispersal was common. The condition was commonest in young adult males, but could present at any age and in women. Medical treatment was often successful initially, but continued to control pressure in only 17 of 42 patients.
Laser trabeculoplasty helped some patients. Drainage operations of various types were successful in 19 of 23 cases. Iris angiography showed evidence of vascular hypoperfusion of the iris which probably precedes pigment dispersal and suggests that the ultimate aetiology may be a congenital deficiency of the mesodermal support tissues of the iris. Some degree of iris stromal atrophy is also common and may become marked. Pigment dispersal from the pigment epithelium of the iris occurs in susceptible individuals and may be associated with the insertion of the dilator muscle. The term anterior segment pigment dispersal seems appropriate as the condition is limited to the anterior segment.     

Pigmentary glaucoma: a clinical review of anterior segment pigment dispersal syndrome

Sixty-eight cases (44 males, 24 females) of anterior segment pigment dispersal syndrome are reviewed. Five patients had no rise in intraocular pressure, 38 had ocular hypertension and 25 had glaucoma as shown by optic disc cupping and field loss. All cases had heavy deposition of pigment in the drainage angle together with Krukenberg spindles and/or light reflux through the iris. Other evidence of anterior segment pigment dispersal was common. The condition was commonest in young adult males, but could present at any age and in women. Medical treatment was often successful initially, but continued to control pressure in only 17 of 42 patients. Laser trabeculoplasty helped some patients. Drainage operations of various types were successful in 19 of 23 cases. Iris angiography showed evidence of vascular hypoperfusion of the iris which probably precedes pigment dispersal and suggests that the ultimate aetiology may be a congenital deficiency of the mesodermal support tissues of the iris. Some degree of iris stromal atrophy is also common and may become marked. Pigment dispersal from the pigment epithelium of the iris occurs in susceptible individuals and may be associated with the insertion of the dilator muscle. The term anterior segment pigment dispersal seems appropriate as the condition is limited to the anterior segment.     

先天性葡萄膜外翻

先天性葡萄膜外翻是一种罕见的眼科疾病,以虹膜基质前表面存在虹膜色素上皮、房角发育异常、进行性青光眼为特征.一般为非进行性,最主要的并发症是发展为先天性或青少年型青光眼.此病与神经嵴发育异常相关,可与某些遗传病伴发.较为特殊的临床表现是环绕瞳孔的虹膜色素膜样外翻,终止于虹膜的中周部.边界清晰,外翻的程度各方向不尽相同.几乎所有患者在确诊后都行滤过性手术治疗.     

先天性葡萄膜外翻

先天性葡萄膜外翻是一种罕见的眼科疾病,以虹膜基质前表面存在虹膜色素上皮、房角发育异常、进行性青光眼为特征.一般为非进行性,最主要的并发症是发展为先天性或青少年型青光眼.此病与神经嵴发育异常相关,可与某些遗传病伴发.较为特殊的临床表现是环绕瞳孔的虹膜色素膜样外翻,终止于虹膜的中周部.边界清晰,外翻的程度各方向不尽相同.几乎所有患者在确诊后都行滤过性手术治疗.     

PROGRESSIVE CORNEAL ENDOTHELIAL CELL CHANGES IN ANTERIOR SEGMENT DISEASE

We have demonstrated marked changes in the corneal endothelium in some groups of patients with ocular anterior segment disease including chronic cyclitis, both heterochromic an! classical pseudoexfoliation of the lens capsule, and anterior segment pigment dispersal syndrome. The most striking changes occurred in heterchromic cyclitis with reduced endothelial cell counts (p>0.01) and altered cellular morphology. In almost all eyes with cyclitis endothellal belbs were seen. In eyes with unilateral pseudoexfoliation of the lens capsule there was a lower endothelial cell count with pleomorphisrn and polymegathism, the changes being somewhat more marked with raised introcular pressure (p>0.07). In anterior segment pigment dispersal syndrome there was an even smaller reduction in count (p>0.05)with mild changes in morphology. Factors producing endothelial cell changes included hypoperfusion of the iris with microneovascularisation of the iris stroma, intercellular bleb formation with oedema of the corneal endothelium. and raised intraocular pressure. A normal iris circulation is important to the integrity of the corneal endothelium.     

Progressive corneal endothelial cell changes in anterior segment disease

We have demonstrated marked changes in the corneal endothelium in some groups of patients with ocular anterior segment disease including chronic cyclitis, both heterochromic and classical, pseudoexfoliation of the lens capsule, and anterior segment pigment dispersal syndrome. The most striking changes occurred in heterochromic cyclitis with reduced endothelial cell counts (p less than 0.01) and altered cellular morphology. In almost all eyes with cyclitis endothelial belbs were seen. In eyes with unilateral pseudoexfoliation of the lens capsule there was a lower endothelial cell count with pleomorphism and polymegathism, the changes being somewhat more marked with raised intraocular pressure (p less than 0.01). In anterior segment pigment dispersal syndrome there was an even smaller reduction in count (p less than 0.05) with mild changes in morphology. Factors producing endothelial cell changes included hypoperfusion of the iris with microneovascularization of the iris stroma, intercellular bleb formation with oedema of the corneal endothelium, and raised intraocular pressure. A normal iris circulation is important to the integrity of the corneal endothelium.     

Asymmetric pigment dispersion in a patient with the unilateral Adie pupil

PURPOSE: Pigmentary glaucoma is a bilateral disorder. When it occurs asymmetrically or unilaterally, a cause should be sought because it may help us to understand the pathophysiology of this condition better. We describe a patient with unilateral pigmentary glaucoma and the Adie pupil in the same eye and discuss the possible role of the Adie pupil in the development of the pigmentary glaucoma. METHODS: A case report. A 37-year-old woman presented with asymmetric pigment dispersion resulting in pigmentary glaucoma in the right eye and an unilateral Adie pupil in the same eye. RESULTS: We believe that the dilated Adie pupil in the right eye might have resulted in a decreased amount of relative pupillary block. This, then, might have led to an increased contact between the posterior iris and the zonules, resulting in greater pigment dispersion and trabecular obstruction in the right eye. CONCLUSION: It has been proposed that the pigment is liberated from the iris pigment epithelium because of the mechanical rubbing of the posterior iris against the anterior zonular packets. Our case supports this proposed mechanism of pigment release.     

Iridectomy of the anterior iris stroma using the vitreocutter during phacoemulsification in patients with iridoschisis

We present a technique to manage iridoschisis. This technique for anterior iridectomy of the affected iris fibers avoids intraoperative obstruction of the phaco tip and prevents postoperative complications such as corneal decompensation and glaucoma. Before the capsulorhexis is created, a vitreocutter is inserted in the anterior chamber and used to cut the iris strands at the site of the iridoschisis, making an anterior sectorial stromal iridectomy and preserving the iris pigment epithelium. Phacoemulsification is then performed. After the pupil is constricted with carbacol, remnants of the loose anterior iris fibers are excised with the vitreocutter and the scleral incision is sutured.     

The complex study of the iris in transformed light

Complex investigations of the iris in a transformed light by methods of iridochromoscopy, iridochromophotography, examination in a polarized light, transillumination in red light and fluorescence angiography was conducted in 25 eyes of patients with open-angle glaucoma, 10 eyes of patients with anterior flaccid uveitis and in 23 healthy eyes (a control group). It was found that in patients with open-angle glaucoma and anterior flaccid uveitis trophic and vascular changes in the iris predominated, as compared with control. The most typical for open-angle glaucoma changes in the iris were atrophy of the stroma with predominant involvement of the pupillary zone, exogenic pigmentation of the pupillary and ciliary zones, destruction of the pigment margin of the pupil, thickening of the anterior border layer, pseudoexfoliation of the pupillary margin, defects in the posterior pigment layer, being more extensive in the pupillary zone, as well as disturbances in permeability of the iris in a combination with hypoperfusion and rare bundles of microneovascularization in the area of a lesser arterial circle and the ciliary zone. In case of flaccid uveitis, the most frequent changes were diffuse atrophy of the iris, efflorescence of the pupillary margin, destruction of the pigment rim of the pupil, multiple defects in the posterior pigment layer along its whole length, increased permeability of vessel, microneovascularization of the iris stroma in a form of a thin vascular network.     

Congenital ectropion uveae with glaucoma

Congenital ectropion uveae (CEU) is a rare, nonprogressive anomaly characterized by the presence of iris pigment epithelium on the anterior surface of the iris stroma, often associated with neurofibromatosis and occasionally with other ocular anomalies. We present eight patients with unilateral CEU. Seven patients had glaucoma in the involved eye, while the eighth was a 10-week-old infant. In the two patients with bilateral glaucoma, the second eye was similar to the first, but without CEU. Three patients had neurofibromatosis, two had facial hemihypertrophy, one had Rieger's anomaly, one had Prader-Willi syndrome, and one had no systemic anomalies. Two had initially been misdiagnosed as having a large pupil in the involved eye and one as having a Horner's syndrome in the uninvolved eye. The finding of CEU in an infant warrants continued observation for the development of glaucoma and disorders of neural crest origin.     

白内障周边虹膜的组织学研究

对白内障术中切除的周边虹膜进行了光镜和透射电镜观察。虹膜前表面未见内皮细胞被覆。虹膜基质的色素细胞及微血管内皮细胞中见到与细胞长轴方向一致的束状微丝。基质内有粗细不同的4种胶原纤维。色素上皮前层细胞向基质深层发出平滑肌突.     

Bilateral acute depigmentation of the iris first misdiagnosed as acute iridocyclitis

Acute depigmentation of the iris is a new condition characterized by pigment dispersion in the anterior chamber, depigmentation of the iris stroma, and pigment deposition in the anterior chamber angle. A 33-year-old woman using a topical corticosteroid every 2 h for the treatment of acute iridocyclitis was referred to our clinic to seek another opinion because her symptoms had not improved. An ocular evaluation of the patient revealed pigment precipitates on the corneal endothelium, pigment dispersion in the anterior chamber, symmetrical diffuse depigmentation, granularity of the iris stroma, and pigment deposition in the trabecular meshwork. These findings suggested a diagnosis of bilateral acute depigmentation of the iris (BADI) instead of iridocyclitis. Clinicians should be careful in the differential diagnosis of iris depigmentation from iridocyclitis to avoid the unnecessary use of high-dose topical corticosteroids.     

Morphologic and clinical features of retrocorneal melanin pigmentation and pigmented pupillary membranes: Review of 225 cases

Observations based on clinical and histopathologic data from 200 consecutive cases of retrocorneal pigmentation by melanin-containing cells (RCP) and 25 cases of pigmented pupillary membranes (PPM) are reported. RCP was observed to be formed by four cell types, either alone or in combinations. The characteristic morphologic appearance of each cell type is described, and the significance and the predisposing factors for the various forms of RCP are outlined. RCP from endothelial-cell pigment phagocytosis, and in cases of resulting pigmented macrophages, was found to be a rather nonspecific reaction to release of pigment granules of iris pigment epithelium after surgical trauma, inflammation, and with the pigment dispersion syndrome. RCP from iris pigment epithelium was especially associated with anterior segment trauma with iris incarceration and peripheral anterior iris synechiae. This form was the least frequent. Most frequent in this series was RCP from iris stromal melanocytes. This seemed to be stimulated by surgical or accidental trauma and by corneal inflammation. Iris melanocytization of the anterior chamber angle and posterior corneal surface appeared to be related to the formation of retrocorneal fibrous tissue, the presence of anterior synechiae, and the development of secondary open-angle glaucoma. PPM are formed mostly by a combination of the pigmented cells of the iris. The predisposing conditions for formation of PPM were the same as for RCP. However, no correlation of implicated cell types and predisposing factors was detected. With these findings the importance of iris tissue, especially iris stromal melanocytes, in these basic reactions to anterior segment trauma or corneal inflammation is discussed.     

Acute primary ischemic iris atrophy

Five patients are described with acute primary ischemic iris atrophy with almost complete loss of the normal radial vessels of the iris and fine microneovascularization. The atrophy of the iris was marked with a thin atrophic stroma, widely dilated pupil, and extensive loss of pigment from the posterior surface of the iris. The condition is of unknown etiology but occlusion of the greater vascular circle of the iris is possible. Iris angiography showed an almost total loss of the radial vessels of the iris with some patchy microneovascularization. In recent cases, the onset was acute and all patients had a raised intraocular pressure (IOP) except one who had already undergone a drainage operation. There was an accompanying low-grade uveitis or cyclitis in the chronic stage in all cases. The condition was unilateral and the posterior segment of the eye was normal so that good visual function was possible if the accompanying cataract and glaucoma were appropriately managed.     

Congenital ectropion of the iris epithelium and glaucoma

Two cases of unilateral ectropion uveae with ipsilateral juvenile glaucoma are reported including one with ipsilateral ptosis. This rare, non progressive anomaly, is characterized by the presence of iris pigment epithelium on the anterior surface of iris stroma, quite often associated with neurofibromatosis, ipsilateral ptosis or Rieger's syndrome. Congenital or juvenile glaucoma is almost systematically associated with the condition and must be evaluated and treated. Pathogeny of the anomaly has to be interpreted keeping in mind the concept of neurocristopathy, i.e. developmental anomalies of neural crest origin tissues.     

Anterior Segment Ischemia in Viper Bite

Purpose: To describe the clinical and histopathological features of post viper bite anterior segment ischemia.

Methods: Seven patients with ocular complications following viper bite referred to uveitis clinic had slit-lamp examination, intraocular pressure (IOP) measurement, and fundus evaluation. Iris and fundus fluorescein angiography was performed on 2 patients. Histopathological examination was performed on iris tissues collected during cataract surgery.

Results: Strikingly similar clinical findings were noted, including circumpupillary superficial iris atrophy, mid dilated fixed pupil, marked pigment dispersion, low IOP, and cataract. All clinical signs were noted only in the anterior segment; the posterior segment was normal. Histopathology of iris revealed atrophy of iris stroma, necrotic iris pigment epithelium, and infiltration of T lymphocytes and fibrous membrane. Poor visual outcome was noted in patients with low IOP.

Conclusion: Viper bite victims presented with clinical and histopathological signs of anterior segment ischemia and secondary inflammatory signs mimicking uveitis.     

Iris atrophy with hypoperfusion and microneovascularisation.

A series of 17 patients with stromal atrophy, hypoperfusion, and microneovascularisation of the iris investigated in the Glaucoma Investigation and Research Unit are described, and their iris angiograms were compared with those of normal irides of patients in the same age group seen in general clinics. In all but one of the 17 cases this iris atrophy was associated with glaucoma or ocular hypertension, which appeared to be secondary to the iris changes. The condition was bilateral and presented a typical slit-lamp appearance, with subtle evidence of microneovascularisation. There was neither history nor clinical evidence of previous trauma, heterochromia, or intraocular inflammation. The commonest form of iris atrophy affected the inner third of the iris stroma in a patchy manner, often with sparing above. However, diffuse atrophy occurred in two cases, and there were two cases of 'senile tears' of the iris. Some accompanying atrophy of the pigment epithelium was usual but less prominent. The changes on fluorescein angiography of the iris included the late appearance of dye with a long arteriovenous circulation time, fewer arteries than normal with sectorial hypoperfusion, leakage of dye from the pupil margin and peripupillary neovascularisation, stromal tufts, and sometimes more complex stromal microneovascularisation. An expanded prominent lesser vascular circle was a common feature of the condition. The condition is bilateral and distinct from other forms of iris atrophy. In all cases the iris changes appeared to be secondary to the vascular hypoperfusion and were not consistently associated with evidence of gross vascular disease. All patients had grey (blue) irides, and this may be an aetiological factor. The condition appears common enough to form a significant group of glaucoma patients and to be a separate clinical entity.     

Novel grading system for pupillary ruff changes and associated features

Background: To evaluate the reproducibility of a new system for grading pupil ruff changes and associated findings. Design: Observational comparative study. Participants: Forty‐seven photograph sets including iris, pupil edge and ruff, and inferior anterior chamber drainage angle. Methods: A novel system for recording pupillary ruff changes was developed, along with reference iris, pupil and gonioscopy images. A prospective masked agreement study was undertaken using two observers who graded the photograph sets using this new system. Parameters included pupillary ruff absence and abnormality, pupil edge pigment, trabecular meshwork pigment, Sampaolesi line pigment, iris root pigment, and pigment ‘lumps’ and ‘piles’. Main Outcome Measures: Intraobserver and interobserver agreement for the parameters of the grading system, assessed with the intraclass correlation coefficient and Bland–Altman plots. Results: Photographs of 47 eyes of 47 glaucoma suspects and glaucoma patients were evaluated. Agreement percentages of ≥95% (average 96%) and ≥60% (average 70%) were obtained for intraobserver and interobserver agreement, respectively. The average interobserver single‐measure intraclass correlation coefficient and repeat‐measures intraclass correlation coefficient were 0.75 (range 0.54–0.88) and 0.85 (range 0.70–0.94), respectively. There was a non‐significant trend towards interobserver systematic bias on one of the nine parameters (iris stroma pigment at the pupil edge). Conclusion: This grading system provides a reliable and reproducible system for encoding of clinical signs of pupil ruff atrophy for clinical research.     

Fluorescein angiography and fluorophotometry of the iris in pseudoexfoliation of the lens capsule.

Fluorescein iris angiography and fluorophotometry were performed on a series of 9 patients with bilateral and 11 with unilateral pseudoexfoliation, 12 bilateral aphakes with pseudoexfoliation, and 7 unilateral aphakes with bilateral pseudoexfoliation. Angiography showed a loss of radial iris vessels, a heavy leak of fluorescein from the pupil margin, progressive neovascularisation of the outer 2/3 of the iris, and less constantly a network of fine new vessels in the inner 1/3 of the iris stroma. These changes were absent in unaffected eyes. After cataract extraction there seemed to be a definite lessening of fluorescein leak from the pupil margin. Fluorophotometry showed a much higher fluorescein concentration at the anterior focus in eyes with pseudoexfoliation than in normal controls or in fellow unaffected eyes. There was a much smaller rise in fluorescein concentration at the posterior focus in a minority of affected eyes. The ranges of fluorescein concentrations at the anterior focus in both phakic and aphakic patients with bilateral pseudoexfoliation did not differ significantly. The concentration at the anterior focus of unilateral aphakes with bilateral pseudoexfoliation was lower than in the fellow phakic eye. These findings suggest that the neovascular reaction seen in pseudoexfoliation is associated with patchy occlusion of the normal iris vasculature, occurs in the anterior segment of the eye, and does not continue to progress after removal of the lens.