Protective effects of biodegradable collagen implants on thinned sclera after strabismus surgery: a paired-eye study.

PURPOSE: To determine the efficacy of a biodegradable Ologen (Aeon Astron Europe BV, Leiden, The Netherlands) collagen matrix in reducing the blue color change due to exposed thinned sclera after strabismus surgery. METHODS: Fourteen patients with intermittent exotropia undergoing symmetric bilateral lateral rectus recession surgery were included in this prospective, randomized, paired-eye controlled study. In each patient, Ologen was implanted at the original rectus insertion site in one randomly selected eye; the other eye underwent conventional surgery. Ologen was inserted under the conjunctiva without suturing, covering the muscle insertion site. Conjunctival color change was analyzed using computer-based image analysis immediately and 1 week, 1 month, and 3 months postoperatively. Slit-lamp photographs of each eye were evaluated using contrast limited adaptive histogram equalization (CLAHE), Canny edge, and the RGB (red-green-blue) model. Secondary outcomes were conjunctival and sclera thickness 3 months postoperatively determined by anterior segment optical coherence tomography. RESULTS: Immediately and 1 week postoperatively all color models showed no significant differences between Ologen-implanted and control eyes. Three months postoperatively, Ologen-implanted eyes exhibited significantly lower CLAHE (P = 0.041) and RGB model blue color (P = 0.008) values than control eyes. Canny edge (P = 0.061) and RGB model red color (P = 0.152) values did not differ between eyes. Conjunctival stroma and episcleral complex thickness was greater in Ologen-implanted eyes than in controls (P = 0.001). CONCLUSIONS: Blue color change was significantly less noticeable in Ologen-implanted eyes than in controls. Thus, Ologen implantation helps prevent visible blue sclera at the original rectus insertion site after lateral rectus recession.

[Complications in the treatment of ocular surface squamous neoplasia with interferon α­2b in rheumatoid arthritis]. / Komplikationen der Behandlung von Neoplasien des konjunktivalen Plattenepithels mit Interferon-α-2b bei rheumatoider Arthritis.

BACKGROUND: Interferon α­2b (IFN α­2b) is an established and well-tolerated treatment for ocular surface squamous neoplasia (OSSN). METHOD: Report of complications in two patients with OSSN and rheumatoid arthritis treated with adjuvant topical IFN α­2b. RESULTS: One patient developed a scleral melt and the other one severe keratitis. After discontinuing treatment with IFN α­2b both patients showed considerable improvement. CONCLUSION: Immunosuppressed patients with OSSN under topical IFN α­2b should be closely monitored for early detection of complications.

Amniotic membrane for reducing the formation of adhesions in strabismus surgery: experimental study in rabbits.

PURPOSE: To evaluate the effect of amniotic membrane in reducing inflammation, fibrosis, adhesion formation, and ocular motility restrictions following strabismus surgery. METHODS: In the first stage of this prospective, randomized study, 17 rabbits underwent superior rectus muscle recession in both eyes. Surgery was performed in the same manner, but human amniotic membrane was placed over the muscle without sutures in the right eye after recession. After 15 days, the rabbits were killed and their orbits were exenterated and evaluated histopathologically to quantify tissue inflammation and fibrosis. In the second stage, 5 rabbits underwent the same procedure but were killed after 30 days. A dynamometer was used to measure the force required to displace all eyes. RESULTS: At 15 days postoperatively, eyes with amniotic membrane exhibited an increased inflammatory response and less fibrosis than eyes without amniotic membrane. At 30 days postoperatively, eyes with amniotic membrane continued to exhibit increased inflammation and less fibrosis than eyes without amniotic membrane. In the dynamometer test, more force was needed to displace eyes without amniotic membrane after 15 days, but there was no significant difference between the forces required at 30 days. CONCLUSIONS: Human amniotic membrane in rabbits led to an increase in the inflammatory process and a decrease in fibrosis formation following strabismus surgery.

[Application of mitomycin in primary covered sclerotomy]. / Die gedeckte Sklerotomie mit primärer Mitomycin-C-Applikation.

BACKGROUND: The covered sclerotomy is a minimally invasive, standardized fistulating glaucoma surgical procedure with reduced risk of complications. Early postoperative bleb fibrosis is a main success-limiting problem. In this clinical study IOP follow-up and the one year success rate after primary application of mitomycin C (MMC) is analyzed. PATIENTS AND METHODS: In 76 eyes with advanced glaucoma and without previous fistulating surgery, a covered sclerotomy combined with 3-minute-application of MMC0,02 % was performed. Over a period of 12 months, bleb and pressure were controlled regularly. The success rates were compared primarily with data from an earlier study without application of MMC. RESULTS: The mean age of the patients was 70 ± 11 years. 45 % had a pseudoexfoliation syndrome while 41 % were pseudophakic. The mean intraocular pressure (IOP) was 27 ± 8,5 mmHg preoperatively. After 12 months it was 16,2 ± 4,3 mmHg (p < 0.05) with a mean IOP reduction of 40 %. The absolute success rate (intraocular pressure < 21 mmHg without antiglaucoma therapy) was 58 % and the relative success rate (intraocular pressure < 21 mmHg under treatment) was 71 %. A revision or a needling was performed in 22 eyes (29 %). MMC-related complications were not observed. CONCLUSION: Through the additional MMC application on the base of the primary covered sclerotomy a significant pressure reduction could be achieved. 58 % of the patients didn't need any glaucoma medicine. The absolute success rate was higher than without additional inhibitions of the fibrosis.

[Keep an eye on the side effects]. / Nebenwirkungen im Auge behalten.

A 52-year-old man presented with a progressive grey-black pigmentation of facial skin, sclera and teeth. The cause was long-term ingestion of minocycline, as confirmed by history and skin biopsy. Minocycline-induced hyperpigmentation can be divided into four main patterns based on clinical appearance, distribution, light- and electron microscopic characteristics. Some patterns can manifest within weeks of initiating therapy. One must be alert to the early signs and warn the patient about the often cosmetically disturbing and persistent minocycline-induced hyperpigmentation.

The effect of a temperature-sensitive poloxamer-alginate-CaCl2 mixture after strabismus surgery in a rabbit model.

PURPOSE: To determine the efficacy of a temperature-sensitive poloxamer-alginate mixture in reducing adhesions after strabismus surgery in a rabbit model. METHODS: The superior rectus muscle was recessed in each of 36 eyes from 18 rabbits. One randomly assigned eye in each rabbit was treated with a poloxamer-alginate mixture (PA group); the other eye was treated with a subconjunctival injection of saline (control group). The adhesions between the superior rectus muscle, sclera, and conjunctiva were clinically evaluated by a masked observer at 1 day, 1 week, and 4 weeks after surgery. Inflammation was analyzed by hematoxylin and eosin staining and anti-CD11b staining. Late fibrosis was assessed by the Masson trichrome and α-smooth muscle actin staining. Adhesion, inflammation, and fibrosis were graded on a scale of 0-4. RESULTS: There was no significant between-group difference in the degree of adhesion at 1 day and 4 weeks after surgery. However, the degree of adhesion in the PA group was lower than that in the control group at postoperative week 1 (P < 0.05). Acute inflammation was similar between the groups (P > 0.05). At postoperative week 4, inflammatory cell infiltration was reduced in the PA group (P = 0.046). A significant between-group difference in late fibrosis at postoperative week 4 was observed through the Masson trichrome (P = 0.024) and α-smooth muscle actin staining (P = 0.025). CONCLUSIONS: The poloxamer-alginate mixture significantly decreased adhesion after strabismus surgery in a rabbit model. Additional studies are warranted to evaluate the use of this mixture in preventing postoperative adhesions.

[Pathophysiology of fibrotic encapsulation of episcleral glaucoma drainage implants: modification for improvement of clinical results]. / Pathophysiologie der fibrösen Abkapselung epibulbärer Glaukom-Drainage-Implantate : Modifikation zur Verbesserung der klinischen Ergebnisse.

Episcleral glaucoma drainage implants (GDI) are being used increasingly more as a surgical option for lowering intraocular pressure (IOP). One of the main reasons for failure to control IOP is the formation of water-impervious fibrotic tissue around the base plate of GDIs that prevents effective resorption of the drained aqueous humor and thus leads to an increase in IOP. Surgical removal of the fibrotic tissue can often rescue implant function; however, repeated encapsulation can often not be prevented and necessitates additional interventions up to the removal of the implant itself. The reasons for the fibrotic reaction are not fully understood. Apart from patient-dependent mechanisms that are also involved in bleb scarring after trabeculectomy, implant properties, such as size, shape, surface properties and biomaterial probably contribute to the encapsulation process. Based on the literature on this topic this article looks at possible ways of improving the design of currently used drainage implants including the potential use of GDIs as a carrier for antifibrotic medication released at low doses over an extended period of time.

Effects of solid hyaluronic acid film on postoperative fibrous scar formation after strabismus surgery in animals.

PURPOSE: The purpose of this study was to investigate the inhibitory effect of solid hyaluronic acid-carboxymethylcellulose film on the formation of wound adhesion after strabismus surgery on rabbit eyes. METHODS: The authors performed strabismus surgery on rabbit eyes with hyaluronic acid film applied under and above the muscles. Histological examination was performed 90 days postoperatively using Masson trichrome staining. The length of adhesion tissues in the operated area was quantitatively compared between film-treated and control eyes. RESULTS: Hyaluronic acid film significantly prevented the formation of adhesions between muscle, conjunctiva, and sclera after strabismus surgery (t test, P < .05). CONCLUSION: The current results indicate that hyaluronic acid film can inhibit the formation of postoperative adhesion around conjunctiva, muscle, and sclera to some extent. The authors conclude that this substance offers potential benefits for ophthalmic surgery, not only with strabismus surgery but also procedures such as scleral buckle.

Sclerochorioretinal abnormalities in hypercholesterolemic rabbits treated with rosiglitazone.

BACKGROUND AND OBJECTIVE: To evaluate early retinal, choroidal, and scleral abnormalities induced by a hypercholesterolemic diet and the prevention of these abnormalities after oral administration of rosiglitazone in rabbits. MATERIALS AND METHODS: Fifty-four New Zealand rabbits were divided into four study groups: control group, normal diet; group 1, hypercholesterolemic diet; group 2, hypercholesterolemic diet associated with daily administration of 3 mg of rosiglitazone from day 14 after beginning the diet; and group 3, hypercholesterolemic diet associated with daily administration of 3 mg of rosiglitazone since the beginning of the experiment. Sclera and choroid underwent histologic and histomorphometric analyses. Retina underwent immunohistochemical analysis with anti-calretinin and anti-glial fibrillary acidic protein (GFAP) antibodies. RESULTS: No abnormalities were observed in the control group. Group 1 had significant increases in scleral and choroidal thicknesses compared with the control group (P < .01) and group 3 (P < .05). Group 1 presented significant increases in immunoreactivity (P < .001) to the anti-calretinin antibody compared with the other groups. Groups 2 and 3 had significant (P < .002) increases in calretinin immunoreactivity compared with the control group. GFAP was negative in all groups. CONCLUSION: The hypercholesterolemic diet induced early retinal, choroidal, and scleral abnormalities. Rosiglitazone preserved the structural anatomy.

Effects of amniotic membrane on wound healing and adhesions in experimental strabismus surgery.

PURPOSE: To evaluate the efficiency of amniotic membrane in prevention of adhesion formation after strabismus surgery. METHODS: A prospective, controlled study was conducted on 20 eyes of 10 pigmented rabbits. After disinsertion of the superior rectus muscle, under the muscle insertion area to induce adhesion formation, a partial-thickness 4 x 4 mm sclerectomy was performed in both eyes. In the right eyes, a piece of appropriate size human amniotic membrane was sutured on the sclerectomy site. As the control group, left eyes were operated with a similar procedure but without amniotic membrane transplantation. After 2 months, both eyes were enucleated to perform histopathologic examination. RESULTS: There was no adhesion between the sclera and muscle in the amniotic membrane group; however, there were various degrees of adhesions in the control group (p=0.004). Fibrosis in rectus muscle was present in 40% of the specimens in the amniotic membrane group and 90% in the control group with a higher grade (p=0.023). The mean number of inflammatory cells was significantly higher in the amniotic membrane group (p=0.005). CONCLUSIONS: According to our results, amniotic membrane has antifibrotic effect but no anti-inflammatory effect in rabbit eyes due to possible xenograft reaction to human tissues. It is effective in prevention of adhesion formation with possible physical barrier action.

Seprafilm as a new antifibrotic agent following trabeculectomy in rabbit eyes.

PURPOSE: To investigate the efficacy of Seprafilm (Genzyme, Framingham, MA, USA) in preventing postoperative adhesion between the conjunctiva and sclera after glaucoma filtering surgery. METHODS: A subconjunctival pocket was created and Seprafilm was inserted into the pocket in nine rabbits (Seprafilm group), whereas in a second group, a subconjunctival pocket was created in nine rabbits but no Seprafilm was inserted (non-Seprafilm group). The postoperative adhesion force was measured 4 weeks after surgery. For the trabeculectomy study, trabeculectomy was performed and Seprafilm placed on the scleral flap in five rabbits (Seprafilm trabeculectomy group), whereas in a second group, trabeculectomy was performed in five rabbits but no Seprafilm was placed (non-Seprafilm trabeculectomy group). Filtering bleb formation and intraocular pressure (IOP) was evaluated on days 1, 3, 5, 7, 14, 21, and 28 following surgery. The eyes were enucleated for histologic evaluation 4 weeks after surgery. RESULTS: The mean adhesive force between the conjunctiva and sclera in the Seprafilm group (125.6 +/- 94.5 mmHg) was lower than that of the non-Seprafilm group (263.3 +/- 79.3 mmHg) (P = 0.0041, unpaired t test). A more prominent bleb was observed in the Seprafilm trabeculectomy group than in the non-Seprafilm trabeculectomy group. Histologically, the subconjunctival space was larger in the Seprafilm trabeculectomy group than in the non-Seprafilm trabeculectomy group. Mean IOP was significantly lower in the Seprafilm trabeculectomy group (9.9 +/- 0.6 mmHg) than in the non-Seprafilm trabeculectomy group (11.9 +/- 0.7 mmHg) 4 weeks after surgery (P = 0.0044, unpaired t test). CONCLUSIONS: Seprafilm can reduce postoperative conjunctiva-sclera adhesion and may be a desirable antifibrotic agent for trabeculectomy in the early stages of wound repair.

Polytetrafluoroethylene/polylactide-co-glycolide laminate containing dexamethasone allows delayed adjustable strabismus surgery in a rabbit model.

PURPOSE: To determine the usefulness of polytetrafluoroethylene/polylactide-co-glycolide (PTFE/PLGA) laminate containing dexamethasone in delayed adjustable strabismus surgery. METHODS: A prospective, masked-observer, controlled study was performed in rabbits. Fifty-two rabbit eyes were divided into three groups. After a recession of the superior rectus muscle (SRM), a PTFE/PLGA containing or not containing dexamethasone or balanced saline solution was applied beneath and over the SRM in the three treatment groups: the PTFE/PLGA-dexamethasone group (the P-D group), the PTFE group (the P group), and the control group (group C). Delayed adjustment was performed once on each SRM at 3 or 5 weeks after surgery by a masked observer. Adjustment lengths, the forces required, and degrees of adhesions were evaluated. RESULTS: In the control group, adjustment was possible in no eyes at 3 or 5 weeks after surgery. In group P, adjustment was possible in 6 of 10 eyes at 3 weeks after surgery and in 4 of 9 eyes at 5 weeks after surgery. In group P-D, adjustment was possible in 7 of 9 eyes at 3 and 5 weeks after surgery. CONCLUSIONS: PTFE/PLGA containing dexamethasone was found to allow delayed adjustment in most eyes for up to 5 weeks after surgery without instillation of anti-inflammatory agent.

Evaluation of a new IOL scleral fixation technique without capsular support.

PURPOSE: The purpose of this study was to compare a new intraocular lens (IOL) scleral fixation technique (scleral incision) with the scleral flap surgical technique as regards to efficacy, surgical complications, advantages, disadvantages, and surgery costs in cases with no capsular support. MATERIAL AND METHODS: This was a retrospective study conducted on thirty patients (30 eyes), ten of whom were aphakic, eleven had traumatic cataract, seven had post-phacoemulsification complications, and two had lens luxation. The patients were divided into two groups (I - scleral incision technique and II - scleral flap technique) of fifteen patients each, during a study period lasting eighteen months. The great majority of the procedures were performed under general anesthesia and by the same surgeon. Statistical analysis was done using SPSS. The numerical variables were compared using the t test and the categorical ones using the Fisher exact test. We performed multifactorial analysis to build a model that could predict and compare the complications associated with each technique. An explicative model was built using logistic regression. RESULTS: We observed a threefold higher rate of complications associated with the scleral flap technique when compared to the scleral incision technique. This difference was particularly relevant as regards the occurrence of free scleral flap and hyphema. No statistically significant differences were observed regarding vitreous hemorrhage, choroidal hemorrhage, retinal detachment, difficulty in the external pulling of the Prolene suture, breaking of the Prolene suture, and anterior chamber collapse. We found a significant association between intraoperative complications and the technique used (higher number of complications with the scleral flap) and also with some systemic diseases (patients with hypertension had more intraoperative complications). The number of late complications resulting from the scleral flap technique was much higher than those observed with the scleral incision technique; however, the number of the cases we studied is insufficient to reach statistical significance. CONCLUSION: The duration of the procedure using the IOL scleral incision technique is significantly lower than using the scleral flap technique. Intraoperative complications were significantly associated with the technique used: more frequent with scleral flap. Late complications were mainly associated with systemic and previous ocular diseases.

Comparison of the effectiveness of mitomycin-C and Viscoat on delayed adjustable strabismus surgery in rabbits.

PURPOSE: To determine a way to prevent the formation of adhesions and delay the time of suture adjustment in the course of adjustable strabismus surgery, an animal study was performed to assess and compare the effects of mitomycin C (Mit-C) and viscoelastic material Viscoat (sodium hyaluronate 3% and chondroitin sulphate 4%, Alcon, Fort Worth, TX). METHODS: Right eyes of 47 rabbits were divided into three groups. After recession of the superior rectus muscle (SRM), Mit-C was administered beneath and over the SRM in Group M (16 eyes), Viscoat was administered beneath and over SRM in Group V (16 eyes), and ringer lactate was administered in Group C (15 eyes). SRM then recessed 5 mm with adjustable strabismus surgery technique. Animals in each group were subdivided into 1 and 2, where 1 = adjustment 1 week postoperatively and 2 = adjustment 3 weeks postoperatively. Delayed adjustment was performed in M1 group (6 eyes), V1 group (6 eyes), and C1 group (7 eyes) after 1 week; in M2 group (6 eyes), V2 group (6 eyes), and C2 group (6 eyes) after 3 weeks. Histopathologic examinations were performed for the remaining 10 eyes without suture adjustment at the end of first and third weeks after adjustable strabismus surgery. The possible length and the necessary force to adjust and the degree of adhesions were recorded. RESULTS: When length and strength of the adjustment, adhesions between muscle and sclera, and adhesions between muscle and conjunctiva were taken into consideration, there was no statistically significant difference among M, V, and C groups at postoperative weeks 1 and 3. The force needed for adjustment in M1 group was statistically lower than M2 group. CONCLUSIONS. The intraoperative use of Mit-C (0.4 mg/mL) may decrease adhesion formation in the early postoperative period, especially in the first week. The intraoperative use of Viscoat was not effective in reducing postoperative adhesions and delaying adjustment.

[Prevention of spontaneous scleral perforation during repeated surgery for regmatogenic retinal detachment].

Scleroplastic operations, such as circlage, filling, and their combination widely used in modern surgery so far, have a variety of advantages; however, their drawbacks may also cause severe complications. Among them, there is scleral decubitus (erosion) that is detectable at resurgery when the retina has failed to adjoin after the first operation or when recurrent retinal detachment has developed. The occurrence of this complication makes it impossible to perform an adequate pressing-in due to the fact that spontaneous scleral perforation may occur, which makes it necessary to conduct scleroplasty in this area. For this situation, the authors propose a procedure for surgically treating retinal detachment during re-interventions, which makes it possible to prevent spontaneous scleral perforation, to diminish surgical traumaticity, and to perform a necessary adequate pressing-in for blocking ruptures of the retina with its subsequent adjoining.

Use of polyurethane with sustained release dexamethasone in delayed adjustable strabismus surgery.

AIM: To determine the effect of polyurethane film with sustained release dexamethasone (SRD) in delayed adjustable strabismus surgery. METHODS: A prospective, masked observer, controlled study was performed in rabbits. Thirty four rabbit eyes were divided into three groups. After recession of the superior rectus muscle (SRM), polyurethane film with or without SRD, or balanced salt solution was applied beneath and over SRM in the polyurethane-dexamethasone group (group P-D), polyurethane group (group P), and the control group (group C), respectively. Delayed adjustment was performed once on each SRM at 4 and 6 weeks postoperatively by a masked observer. The possible length to adjust and the necessary force required for the adjustment, as well as the degree of any adhesions, were also evaluated. RESULTS: In the control group, adjustment was impossible in all of the eyes at 4 and 6 weeks postoperatively. In group P-D, adjustment was possible in 11 out of 11 eyes (11/11) 4 weeks postoperatively and in 10/11 eyes 6 weeks postoperatively. In group P, adjustment was possible in 9/11 eyes 4 weeks postoperatively and in 10/12 eyes 6 weeks postoperatively. CONCLUSIONS: Use of polyurethane film with and without SRD could delay adjustment in most eyes for up to 6 weeks postoperatively. Polyurethane is helpful for delaying adjustment in rabbit eyes until 6 weeks postoperatively without the need for frequent topical instillation of steroids.

Effects of intraoperative sponge mitomycin C and 5-fluorouracil on scar formation following strabismus surgery in rabbits.

PURPOSE: To investigate the influence of 5-fluorouracil (5-FU) and mitomycin C (MMC) on the postoperative adhesions following strabismus surgery in rabbits. METHODS: Twenty-one New Zealand white rabbits were used in this prospective, masked, controlled trial. Both eyes of 20 animals underwent 3-mm recession of the superior rectus muscle (SRM). In group I (io animals), one eye of each animal received topical application of MMC (0.2 mg/ml) for 5 minutes and the other eye (control eye) was treated with balanced salt solution (BSS) using an intraoperative sponge. In group II (10 animals), a randomly chosen eye of each animal was treated with 5-FU soaked sponges (50 mg/ml) for 5 minutes and the fellow eye (control eye) with BSS. Two eyes of a rabbit were included as unoperated controls. Four weeks after the surgery, conjunctival vascularity and postoperative adhesions between the SRM Tenon's capsule (TC) and SRM sclera (scl) were assessed. Additionally, eyes were enucleated and evaluated histopathologically for evidence of scarring, granuloma formation, and muscle tissue changes under a light microscope. RESULTS: MMC-treated eyes had a higher rate of avascular conjunctiva compared to both controls and 5-FU-treated eyes. Mean adhesion scores, particularly between the SRM-scl, were lower in eyes treated with antiproliferative agents compared to controls. The difference was statistically significant in MMC-treated eyes for the adhesions between SRM-scl (p = 0.03). Histopathological examination revealed less scarring and granuloma formation in MMC- and 5-FU-treated eyes compared to their control eyes. CONCLUSIONS: MMC, and to a lesser extent 5-FU, are shown to be effective in reducing postoperative scarring following strabismus surgery in rabbits. It seems reasonable to suggest that antimetabolites should be used for cases having an increased risk of postoperative adhesions.

The effect of Seprafilm on adhesions in strabismus surgery-an experimental study.

PURPOSE: Seprafilm (Genzyme, Cambridge, MA) is a bioabsorbable membrane composed of sodium hyaluronate and carboxymethylcellulose. Adhesions occurring after strabismus surgery may affect surgical outcome. The purpose of our study was to histopathologically evaluate the influence of Seprafilm on postoperative adhesions. METHODS: Seven adult male New Zealand albino rabbits were used. The superior rectus muscle was resected 3 mm, and a fornix-based limbal conjunctival dissection was made inferonasally in both eyes. In one eye of each rabbit, Seprafilm was inserted between the conjunctiva and superior rectus and under the dissected inferonasal conjunctiva. The fellow eye of each rabbit, having undergone superior rectus resection and inferonasal conjunctival dissection without Seprafilm, served as the control group. The rabbits were killed and the eyes were enucleated at 6 weeks after surgery. Histopathological sections were analyzed for inflammation and fibrosis by staining them with hematoxylin-eosin and Masson trichrome, respectively. Inflammation and fibrosis were graded on a scale of 0 to 4. RESULTS: Compared with the control eyes, there was no significant difference with regard to inflammation either at the area of superior rectus resection or the area of conjunctival dissection (P.655 and P.157, respectively). Significantly less fibrosis occurred in the surgical areas where Seprafilm was used compared with the control group (P.046 and P.015, respectively) both at the area of superior rectus resection and the area of conjunctival dissection. CONCLUSION: This study shows that Seprafilm significantly decreases postoperative adhesions between the conjunctiva, muscle, and sclera. Application of Seprafilm may prove useful in strabismus surgery especially where adhesion formation may influence the outcome and in cases where recurrent conjunctival dissection may be needed.

Evaluation of chemoprophylaxis in patients with unilateral retinoblastoma with high-risk features on histopathologic examination.

OBJECTIVES: To identify risk factors for metastatic disease on histopathologic specimens of enucleated eyes from patients with unilateral retinoblastoma, and to evaluate the value of chemoprophylaxis in preventing disease dissemination. METHODS: Medical records from patients with unilateral retinoblastoma who underwent primary enucleation were reviewed at the University of California, San Francisco (1977-1998) and Bascom Palmer Eye Institute, University of Miami, Miami, Fla (1991-1998). All routine histopathologic specimens were reexamined. The extent of tumor invasion into the optic nerve or ocular coats and the prescribed chemoprophylactic regimen were recorded. RESULTS: This retrospective study included 129 patients followed for a median of 54 months. Three patients had tumor invading the sclera. The optic nerve was involved to some extent in 82 patients, 11 of whom had tumor extension beyond the lamina cribrosa. The surgical margin of the optic nerve was involved in an additional 4 patients. The choroid was involved in 43 patients, and was considered massively affected in 12 patients. Anterior segment involvement was observed in 10 patients. Postenucleation chemoprophylaxis was administered to 4 of 4 patients who had tumor cells at the surgical margin of the optic nerve and to 7 of 11 patients with postlaminar disease, all of whom had at least 1 mm of postlaminar tumor extension. External beam radiotherapy was administered to 3/4 and 1/11 of these patients, respectively. Chemoprophylaxis was not administered to patients with choroidal or anterior chamber involvement unless the optic nerve was also involved beyond the lamina cribrosa. One patient with tumor extending to the surgical margin of the optic nerve died of metastatic disease. CONCLUSIONS: Chemoprophylaxis is necessary for patients with tumor extending to the surgical margin of the optic nerve and is likely to be beneficial in preventing metastases in patients with tumor extending beyond the lamina cribrosa. We did not offer chemoprophylaxis to patients with prelaminar optic nerve disease or isolated choroidal involvement, and these patients remained free of disseminated disease.