An updated classification of retinal detachment with proliferative vitreoretinopathy

The Retinal Society classification on proliferative vitreoretinopathy of 1983 has been updated to accommodate major progress in understanding of this disease. There are three grades describing increasing severity of the disease. Posterior and anterior location of the proliferations have been emphasized. A more detailed description of posterior and anterior contractions has been made possible by adding contraction types such as focal, diffuse, subretinal, circumferential contraction, and anterior displacement. The extent of the abnormality has been detailed by using clock hours instead of quadrants.

Central serous chorioretinopathy

Central serous chorioretinopathy (CSC) is a disease of the retina characterized by serous detachment of the neurosensory retina secondary to one or more focal lesions of the retinal pigment epithelium (RPE). CSC occurs most frequently in mid-life and more often in men than in women. Major symptoms are blurred vision, usually in one eye only and perceived typically by the patient as a dark spot in the centre of the visual field with associated micropsia and metamorphopsia. Normal vision often recurs spontaneously within a few months. The condition can be precipitated by psychosocial stress and hypercortisolism. Ophthalmoscopic signs of CSC range from mono- or paucifocal RPE lesions with prominent elevation of the neurosensory retina by clear fluid - typical of cases of recent onset - to shallow detachments overlying large patches of irregularly depigmented RPE. The spectrum of lesions includes RPE detachments. Granular or fibrinous material may accumulate in the subretinal cavity. Serous detachment often resolves spontaneously. From first contact, counselling about the potential relation to stress and glucocorticoid medication is warranted. After 3 months without resolution of acute CSC or in chronic CSC, treatment should be considered. Resolution of detachment can usually be achieved in acute CSC by focal photocoagulation of leaking RPE lesions or, in chronic CSC, by photodynamic therapy. The effect of therapy on long-term visual outcome is insufficiently documented. Reattachment within 4 months of onset is considered a relevant therapeutic target because prolonged detachment is associated with photoreceptor atrophy. This suggests that the value of treatment depends upon proper selection of cases that will not resolve without therapy. Chronic CSC may be difficult to differentiate from occult choroidal neovascularization secondary to CSC. Patients with chronic CSC who receive glucocorticoid treatment for systemic disease can often be managed without having to discontinue this medication.

Proliferative vitreoretinopathy: an overview

Proliferative vitreoretinopathy (PVR) is still the most common cause of failure of surgery for rhegmatogenous retinal detachment, despite the substantial effort that has been devoted to better understanding and managing this condition during the past 25 years. Basic research has indicated that PVR represents scarring, the end stage of the wound-healing process that occurs after retinal detachment surgery. Medical treatment has been directed toward preventing inflammation, the first phase of the wound healing process, and inhibiting cell proliferation, the second phase. The 1983 Retina Society classification was modified in 1989 by the Silicone Study Group, whose classification differentiates between posterior and anterior forms of PVR and recognizes three patterns of proliferation: diffuse, focal, and subretinal. The anterior form has a worse prognosis than the posterior form, and its treatment requires more complex surgical procedures. In this review, risk factors and pathobiology of PVR are discussed, and management of PVR of various degrees of severity are considered.

Cytomegalovirus retinitis and acquired immunodeficiency syndrome

In a series of 157 patients with acquired immunodeficiency syndrome (AIDS), 46 (29%) developed cytomegalovirus (CMV) retinitis. In five patients, CMV retinitis was the initial AIDS-defining opportunistic infection (11% of patients with CMV retinitis and 3% of patients with AIDS). Retinal detachments developed in seven patients (15%) and in four were present before the institution of ganciclovir therapy. Bilateral CMV retinitis was present in 35% of patients at presentation and subsequently developed in nine (60%) of 15 patients while not being treated with ganciclovir. Conversely, none of 18 patients with unilateral disease developed bilateral disease while receiving ganciclovir. Of patients treated with ganciclovir for their CMV retinitis, 81% had a response to the drug, and 61% achieved a complete response, resulting in a nonprogressive and inactive scar. Patients who achieved a complete response with ganciclovir had a significantly longer survival than those who did not, suggesting greater immune compromise in those patients who failed to respond to ganciclovir.

Epidemiology of retinal detachment

A survey of rhegmatogenous retinal detachment during 1976 was conducted on the population of Iowa. The annual incidences (per 100,000 populations) of four types of detachment were determined: nontraumatic phakic (6.1), traumatic phakic (1.0), nontraumatic aphakic (4.9), and traumatic aphakic (0.4). The incidences of nontraumatic phakic detachment for men and women were similar, although there was a preponderance of women that reflected their greater representation in the general population. The proportions of men were significantly higher in traumatic detachments compared with nontraumatic detachments. Men tended to be younger than women for all types of detachment; however, only in nontraumatic aphakic detachment was there a significant difference between mean ages. There was an insignificant preponderance of right eye involvement in all four detachment groups.

Clinical Characteristics of Vogt–Koyanagi–Harada Syndrome in Chinese Patients

PURPOSE

To characterize the clinical features of Vogt-Koyanagi-Harada syndrome (VKH) in Chinese patients.

DESIGN

Retrospective noncomparative case series.

PARTICIPANTS

A total of 410 consecutive VKH patients examined from August 1995 to April 2005.

METHODS

Charts of these patients were reviewed according to international VKH criteria. Patients who consulted us within 2 weeks after a uveitis attack were classified into group 1; between 2 weeks and 2 months into group 2; and after 2 months into group 3. The history and clinical findings of all of the patients were reviewed. Laser flare-cell photometry, fundus fluorescein angiography, indocyanine green angiography, optical coherence tomography, B-scan ultrasonography, and ultrasound biomicroscopy were performed in certain cases. Corticosteroids were mainly used to treat patients in groups 1 and 2, whereas cyclosporine or chlorambucil in combination with corticosteroids were prescribed for patients in group 3.

MAIN OUTCOME MEASURES

Demographics, clinical presentation, and ancillary examinations of the patients in all 3 groups.

RESULTS

The patients were diagnosed as having either complete (n = 273), incomplete (n = 76), or probable (n = 61) VKH syndrome. Exudative retinal detachment and either choroiditis or chorioretinitis were the main findings in group 1. Posterior uveitis with mild to moderate anterior uveitis simulating a nongranulomatous inflammation as evidenced by dust keratic precipitates, anterior chamber cells, and flare was noted in group 2. Recurrent granulomatous anterior uveitis with a "sunset glow" fundus was observed in group 3. Complicated cataract was the most common complication in the patients in group 3. At the final visit, the uveitis was completely controlled in all patients and a best-corrected visual acuity of <20/200 was 1.9%/eye-year, 1.2%/eye-year, and 6%/eye-year in groups 1, 2, and 3, respectively.

CONCLUSION

Vogt-Koyanagi-Harada syndrome in Chinese patients is characterized by early posterior uveitis, and if the syndrome is not controlled, subsequent recurrent granulomatous anterior uveitis. Good visual prognosis is possible if the patients are managed according to a tailored immunosuppressive treatment protocol.

Pigment epithelial proliferation in human retinal detachment with massive periretinal proliferation

Biopsy specimens from vitreous and preretinal membranes, obtained during vitreous surgery from 39 human eyes suffering from massive periretinal proliferation, were examined electron-microscopically. Analysis of the cellular membranes demonstrated mostly cells with epithelial characteristics: polarization of the cells, basal lamina formation, specialized cellular junctions, and microvilli formation. These epithelioid cells contained prominent rough endoplasmic reticulum, glycogen deposits, a multitude of cytoplasmic filaments, some resembling myofilaments, and nonmembrane bound, sometimes wedge-shaped pigment granules. Macrophages were interspersed in the membranes. There was a striking similarity of these findings to those of an experimental model of retinal detachment in owl monkeys, We concluded that most likely the described cells derived from cells of pigment epithelial origin.

Congenital pits of the optic nerve head. II. Clinical studies in humans

The clinical characteristics of 75 eyes with congenital pits of the optic nerve head were reviewed, particularly in relation to associated serous retinal detachment. Retinal detachment was found in 52% of all eyes with pits and 63% of eyes with temporally located pits. Of 20 untreated eyes with a pit and coexistent macular retinal detachment followed for more than one year, 55% (11/20) had visual acuity less than or equal to 6/30 and 75% (15/20) had subretinal fluid at the most recent visit. Visual fields and intravenous fluorescein angiographic characteristics of pits are discussed and clinical evidence is presented supporting the theory that the associated subretinal fluid is derived from liquified vitreous.

The role of the vitreous in diabetic macular edema

The authors assessed retrospectively clinical records of 76 patients (125 eyes) 60 years of age or older with diabetic retinopathy who had undergone a vitreous examination. The groups consisted of 105 eyes (63 patients) with macular edema and 20 eyes (13 patients) without macular edema. Vitreous studies were done using the El Bayadi-Kajiura lens to determine whether or not the posterior vitreous was attached to the retina in the macula. Twenty-one of 105 eyes (20.0%) in the edema group and 11 of 20 eyes (55.0%) in the no-edema group had a detached posterior vitreous. This difference was found to be statistically significant, indicating that diabetic cases without macular edema have a significantly higher rate of posterior vitreous detachment than those with macular edema. This study demonstrates that the vitreous may play a role in diabetic macular edema.

Eye retention after proton beam radiotherapy for uveal melanoma

PURPOSE

To analyze the long-term results of eye retention after conservative treatment of uveal melanoma with proton beam radiotherapy, and to analyze the causes leading to enucleation after this conservative treatment approach.

MATERIALS AND METHODS

This was a prospective, noncomparative, interventional, consecutive case series. A total of 2645 patients (2648 eyes) with uveal melanoma were treated between 1984 and 1999 with proton beam radiotherapy. Data were analyzed as of February 2001. Patients' age ranged from 9 to 90 years, 1284 were men, and 1361 were women. Largest tumor diameter ranged from 4 to 27.5 mm, and tumor height from 0.9 to 15.6 mm. Median follow-up time was 44 months.

RESULTS

The overall eye retention rate at 5, 10, and 15 years after treatment was 88.9%, 86.2%, and 83.7%, respectively. In total, 218 eyes had to be enucleated. Enucleation was related to larger tumor size, mainly tumor height, proximity of posterior tumor margin to optic disc, male gender, high intraocular pressure, and large degree of retinal detachment at treatment time. After optimization of the treatment technique, the eye retention rate at 5 years was increased from 97.1% to 100% for small tumors, from 86.7% to 99.7% for medium, and from 71.1% to 89.5% for large tumors.

CONCLUSIONS

The treatment technique as used today results in excellent eye retention rates, even in less favorable cases such as large tumors and tumors located close to the optic disc. The experience and a continuous quality control program allowed us to improve the 5-year eye retention rate for all tumor sizes. These findings demonstrate the positive impact of experience and quality control-based efforts for treatment technique optimization.

Glial cell proliferation in retinal detachment (massive periretinal proliferation)

In experimental retinal detachment of the owl monkey we observed the formation of preretinal and subretinal membranes which had cellular connections to the retina proper. Based on light microscopic findings we concluded that retinal cells grow out of the retina and build up the preretinal and subretinal tissue. Electron microscopically these cells are identified as astrocytes which grow out through focal interruptions in the internal or external limiting membrane. In the immediate area of outgrowth Muller cell processes praticipate in the formation of the preretinal or subretinal tissue. These glial membranes can cause wrinkling of the internal limiting membrane and the nerve fiber layer or full-thickness folding of the retina. Glial proliferation plays an important role in the development of a complication in retinal detachment which we suggest calling "massive periretinal proliferation" (MPP).

A new approach to treating retinal detachment with macular hole

Six consecutive cases of retinal detachment with macular hole were treated successfully by vitrectomy, partial gas-fluid exchange, and prone positioning of the patient for 12 hours. Macular coagulation and macular buckling were not necessary. In five cases the retina remained flat during follow-up periods ranging from one to 16 months. In one case a small detachment recurred 13 months after surgery. A renewed partial gas-fluid exchange resolved the problem. This new technique simplifies the treatment of such cases and macular function is preserved rather than destroyed. We believe than many detachments with macular holes are caused by vitreous traction.

Filtering surgery in children: barriers to success

The use of trabeculectomy in advanced pediatric glaucoma is reviewed. Intraocular pressure was controlled in only 50% of the patients, and the best visual results was 20/200. Complications of vitreous loss, scleral collapse, ectasia, retinal detachment, and endophthalmitis were encountered. No evidence was found to support the claim that in the seriously compromised buphthalmic eyes, trabeculectomy is safer than other filtering operations since it filters under a scleral flap.

Long-term follow-up of idiopathic central serous chorioretinopathy by fluorescein angiography

Idiopathic central serous chorioretinopathy (ICSC) is typically described as a self-limited, unilateral disease that affects healthy, young adult males. The authors studied 13 patients (14 eyes) who had documented spontaneous resolution of symptomatic macular detachments. These patients were evaluated in a longitudinal fashion to determine the fate of the retinal pigment epithelium (RPE) as viewed angiographically, both in the initially affected eyes and the fellow eyes. At the time of follow-up examination of the initially affected eyes, nonleaking RPE defects had developed inside the areas of previous serous detachment in all cases. Nonleaking RPE defects had developed outside these areas in six (43%) eyes. Two (14%) eyes had new, asymptomatic macular detachments. Six (42%) fellow eyes had new RPE window defects; two (17%) of them also had active RPE dye leakage resulting in asymptomatic macular detachment at the final examination. Four (29%) originally involved eyes and one (8%) fellow eye lost more than two lines of Snellen visual acuity during the follow-up period. The authors' results suggest that ICSC may be a progressive bilateral disease that develops asymmetrically and causes diffuse RPE changes not localized to the area of serous detachment. Long-term follow-up of these patients may, therefore, be advisable.

Complications of vitreous surgery for diabetic retinopathy. II. Postoperative complications

One hundred seventy-nine eyes were analyzed to determine the incidence of postoperative complications after vitrectomy for proliferative diabetic retinopathy. One hundred twenty-nine (72%) of the 179 eyes achieved improved vision, and 117 (65%) were considered visual successes with final vision in the functional range of 5/200 or better. Corneal epithelial defects occurred in 51 eyes (28%), but severe corneal complications were rare, and no eye developed corneal clouding as the sole cause of later visual loss. The lens was retained in 128 eyes (75%), and visually significant lens opacities occurred later in 17% of the phakic eyes. Postoperative iris neovascularization was reduced by not removing the lens, and rubeosis iridis occurred in 15 (13%) of 114 phakic eyes and in 21 (32%) of 65 aphakic eyes (P = 0.012). Vitreous hemorrhage was present in 75% of eyes immediately after surgery and cleared in an average of 6.2 weeks in phakic eyes and 5.4 weeks in aphakic eyes. Fifty-two eyes (29%) had recurrent vitreous hemorrhage after the initial postoperative period. New retinal detachment occurred after surgery in 16% of eyes and was treated successfully in 38%. Reoperations were done in 45 eyes (25%), and 32 (71%) of these were for repair of retinal detachment or removal of nonclearing vitreous hemorrhage. Six eyes (3%) developed phthisis bulbi, and one other eye was enucleated.

Pathogenic mechanisms in proliferative vitreoretinopathy

Landmarks in the development of treatment of retinal detachment include the recognition of the significance of retinal breaks that resulted in the distinction between rhegmatogenous retinal detachment (RRD) and exudative retinal detachment, the development of indirect ophthalmoscopy and scleral depression that allow better visualization of the peripheral area of the retina and better identification of retinal breaks, the recognition of the need to seal all retinal breaks, and the realization that vitreous traction is the major underlying cause of retinal tears and RRD. Scleral buckling procedures combine retinopexy to provide a scar around retinal breaks to seal them and scleral indentation to neutralize vitreous traction; they provided the first effective treatment of RRD. As surgeons gained experience with scleral buckling, they became aware that some RRDs, particularly those with fixed folds and/or a funnel configuration, often could not be repaired using this approach. It was thought that excessive vitreous traction was at fault, and the condition was called "massive vitreous retraction."

Glial Remodeling and Neural Plasticity in Human Retinal Detachment with Proliferative Vitreoretinopathy

PURPOSE

To investigate glial remodeling and neuronal plasticity in adult human retinal detachment complicated by proliferative vitreoretinopathy (PVR) and to grade pathologic changes with a severity scoring system.

METHODS

Sixteen full-thickness retinectomy specimens obtained at retinal relaxing surgery for PVR were fixed in 4% paraformaldehyde immediately after excision and compared to similarly processed normal donor retinas. Agarose-embedded sections (100-microm-thick) were double labeled for immunohistochemistry by confocal microscopy, with antibodies against rod opsin and GFAP; vimentin and M/L-cone opsin; calbindin D and S-cone opsin; and cytochrome oxidase and synaptophysin. These staining patterns formed the basis of a retinal pathology scoring system, and immunohistochemistry was also used to detect CD68, neurofilaments, protein kinase C, growth-associated protein-43, and a pan-cone-specific enzymatic marker. Morphology was also assessed by light microscopy of resin-embedded semithin sections.

RESULTS

Prolonged detachment was characterized by photoreceptor degeneration and intracellular redistribution of opsin proteins to the plasma membrane in the outer nuclear layer (ONL). Remodeling of rod synaptic terminals was characterized by terminal retraction and also by axon extension to the inner retina in most specimens. Rod bipolar cell dendrites extended into the ONL, as did fine, horizontal cell processes. Large ganglion cells showed upregulated neurofilament and GAP-43 expression, with neurites sprouting from somata and axon collaterals. Anti-cytochrome oxidase labeling of surviving inner segments was reduced but detectable in all specimens, as was anti-calbindin D labeling of horizontal and amacrine cells. All specimens demonstrated a marked upregulation of Muller cell and astrocyte expression of GFAP and vimentin. More severe degenerative changes correlated with trauma and prolonged detachment duration when scored according to this system.

CONCLUSIONS

The neural and glial components of detached neurosensory retina complicated by PVR exhibit pathology that changes characteristically with increasing detachment severity. Even in advanced degeneration, most of the structural motifs necessary for functional recovery are retained. Evidence of remodeling in the first-, second-, and third-order neurons of detached adult human retina may represent an attempt to re-establish synaptic connectivity.

Attenuated glial reactions and photoreceptor degeneration after retinal detachment in mice deficient in glial fibrillary acidic protein and vimentin

PURPOSE

To characterize the reactions of retinal glial cells (astrocytes and Müller cells) to retinal injury in mice that lack glial fibrillary acidic protein (GFAP) and vimentin (GFAP-/-Vim-/-) and to determine the role of glial cells in retinal detachment (RD)-induced photoreceptor degeneration.

METHODS

RD was induced by subretinal injection of sodium hyaluronate in adult wild-type (WT) and GFAP-/-Vim-/- mice. Astroglial reaction and subsequent monocyte recruitment were quantified by measuring extracellular signal-regulated kinase (Erk) and c-fos activation and the level of expression of chemokine monocyte chemoattractant protein (MCP)-1 and by counting monocytes/microglia in the detached retinas. Immunohistochemistry, immunoblotting, real-time quantitative polymerase chain reaction (PCR), and enzyme-linked immunosorbent assay (ELISA) were used. RD-induced photoreceptor degeneration was assessed by terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) and measurement of outer nuclear layer (ONL) thickness.

RESULTS

RD-induced reactive gliosis, characterized by GFAP and vimentin upregulation, Erk and c-fos activation, MCP-1 induction, and increased monocyte recruitment in WT mice. Absence of GFAP and vimentin effectively attenuated reactive responses of retinal glial cells and monocyte infiltration. As a result, detached retinas of GFAP-/-Vim-/- mice exhibited significantly reduced numbers of TUNEL-positive photoreceptor cells and increased ONL thickness compared with those of WT mice.

CONCLUSIONS

The absence of GFAP and vimentin attenuates RD-induced reactive gliosis and, subsequently, limits photoreceptor degeneration. Results of this study indicate that reactive retinal glial cells contribute critically to retinal damage induced by RD and provide a new avenue for limiting photoreceptor degeneration associated with RD and other retinal diseases or damage.

Endophthalmitis following open-globe injuries

The incidence of traumatic endophthalmitis may be decreasing due to earlier wound closure and prompt initiation of antibiotics. Risk factors for endophthalmitis include retained intraocular foreign body, rural setting of injury, disruption of the crystalline lens, and a delay in primary wound closure. The microbiology in the post-traumatic setting includes a higher frequency of virulent organisms such as Bacillus species. Recognizing early clinical signs of endophthalmitis, including pain, hypopyon, vitritis, or retinal periphlebitis may prompt early treatment with intravitreal antibiotics. Prophylaxis of endophthalmitis in high-risk open-globe injuries may include systemic broad-spectrum antibiotics, topical antibiotics, and intravitreal antibiotics to cover both Gram-positive and Gram-negative bacteria. For clinically diagnosed post-traumatic endophthalmitis, intravitreal vancomycin, and ceftazidime are routinely used. Concurrent retinal detachment with endophthalmitis can be successfully managed with vitrectomy and use of intravitreal antibiotics along with a long acting gas or silicone oil tamponade. Endophthalmitis is a visually significant complication of open-globe injuries but early wound closure as well as comprehensive prophylactic antibiotic treatment at the time of injury repair may improve visual acuity outcomes.

Ocular perforation following retrobulbar anesthesia for retinal detachment surgery

We encountered three examples of the perforation of the globe by the retrobulbar needle in a series of 4,000 patients who had undergone retinal reattachment surgery with local anesthesia. The presence of significant myopia was a contributing factor in all three cases. We managed the perforation site through the detached retina with cryopexy and external tamponade, and we treated perforations through the attached retinas either with cryopexy at surgery or photocoagulation postoperatively.

Imaging of chorioretinal anastomoses in vascularized retinal pigment epithelium detachments

OBJECTIVE

To identify specific features of pigment epithelium detachments with limited hyperfluorescent lesions (hot spots).

DESIGN

One hundred eighty-two consecutive patients (186 eyes) who had vascularized pigment epithelium detachments and recent onset of symptoms were examined with indocyanine green and fluorescein videoangiography using the scanning laser ophthalmoscope. The choroidal neovascularization complex and macular retinal vessels were studied. The natural history and the effect of laser treatment were evaluated.

RESULTS

Fifty-four eyes had hot spots on indocyanine green angiography. In 50 of these 54 eyes, the video analysis showed an anastomosis of one or more retinal vessels, with the choroidal neovascularization within the hot spot. One or two retinal veins or arteries or both filled with both dyes and were seen to enter into the hot spot. Results of indocyanine green-guided photocoagulation of the hot spot in 28 eyes were disappointing.

CONCLUSION

Continuous recording of the early phases of fluorescein and indocyanine green angiography allowed identification of chorioretinal anastomoses in vascularized pigment epithelium detachments with hot spots at an early exudative stage of age-related macular degeneration in 50 (26.8%) of 186 eyes. The poor outcome of laser photocoagulation could be related not only to the development of an overlying pigment epithelium detachment, but also to the retinal and choroidal vascularization of the lesion.

Drusen as risk factors in age-related macular disease

In a study of 150 consecutive patients with age-related macular disease and unilateral visual loss, the drusen in the better eye were analyzed for size, number, density, and fluorescein angiographic appearance, and these characteristics were compared with the type of the lesion causing visual loss in the contralateral eye. In the fellow eye of an eye with avascular detachment of the retinal pigment epithelium, the drusen were more densely packed, larger, and less fluorescent than in the fellow eye of an eye with primary neovascularization. The characteristics of drusen in fellow eyes of those eyes with pigment epithelial detachments and evidence of subpigment epithelial new vessels were intermediate between the other two groups. Because there is significant symmetry of drusen between fellow eyes, these data imply that the characteristics of drusen are important in the determination of the form of the lesion complicating age-related macular disease.

Prognosis of patients with bilateral macular drusen

Of 71 patients with only bilateral macular drusen, 8 eyes in 7 patients (9.9%) developed exudative maculopathy over an average follow-up of 4.3 years (14.5% cumulative risk). Severe visual loss due to exudative maculopathy occurred in 7 eyes of 6 patients (8.5%) for a 5-year cumulative risk of 12.7%. Features of the drusen were analyzed, but only the association with focal hyperpigmentation (P less than 0.001) and more than minimal drusen confluence (P less than 0.05) were statistically significant. Older patients had more severe drusen. Photostress test delay did not correlate with visual acuity, age, or severity of drusen.