Sequential Descemet's membrane detachments and intraocular lens haze secondary to SF6 or C3F8.

PURPOSE: To report an unusual complication of treatment in the case of a Descemet's membrane detachment. METHODS: Observational case report. RESULTS: A 79-year-old woman presented for elective cataract surgery. Ocular risk factors identified preoperatively included moderately shallow anterior chambers bilaterally, previously treated with bilateral YAG peripheral iridotomies. After a clear corneal section during phacoemulsification, large Descemet's tears on introducing the micro finger and phaco probe were noticed. Conversion to an extracapsular technique was necessary because of poor view. Similar peroperative Descemet's detachments were noticed in the contralateral eye during phacoemulsification by a senior surgeon a year later. Postoperatively, the Descemet's detachments were managed by intracameral SF6 and later C3F8 gas. A few weeks later, a fine haze was noticed under the anterior surface of the intraocular lens (IOL). Corneal edema persisted and corneal decompensation ensued. Both eyes needed penetrating keratoplasties. The right eye needed an IOL exchange due to IOL haze. CONCLUSIONS: In this case the SF6 or C3F8 gas may have produced the unexpected effect of an anterior IOL haze. The mechanism of this phenomenon is unknown. To the knowledge of the authors, this effect has not been observed previously with SF6 or C3F8 gas. This haze was visually significant and required an IOL exchange. To the knowledge of the authors this is the first report of this nature. The authors advise caution when using intracameral SF6 or C3F8 gas for repair of Descemet's membrane detachment with this type of IOL.

Sequential Descemets membrane detachments and intraocular lens haze secondary to SF6 or C3F8.

PURPOSE: To report an unusual complication of treatment in the case of a Descemets membrane detachment. METHODS: Observational case report. RESULTS: A 79-year-old woman presented for elective cataract surgery. Ocular risk factors identified preoperatively included moderately shallow anterior chambers bilaterally, previously treated with bilateral YAG peripheral iridotomies. After a clear corneal section during phacoemulsification, large Descemets tears on introducing the micro finger and phaco probe were noticed. Conversion to an extracapsular technique was necessary because of poor view. Similar peroperative Descemets detachments were noticed in the contralateral eye during phacoemulsification by a senior surgeon a year later. Postoperatively, the Descemets detachments were managed by intracameral SF6 and later C3F8 gas. A few weeks later, a fine haze was noticed under the anterior surface of the intraocular lens (IOL). Corneal edema persisted and corneal decompensation ensued. Both eyes needed penetrating keratoplasties. The right eye needed an IOL exchange due to IOL haze. CONCLUSIONS: In this case the SF6 or C3F8 gas may have produced the unexpected effect of an anterior IOL haze. The mechanism of this phenomenon is unknown. To the knowledge of the authors, this effect has not been observed previously with SF6 or C3F8 gas. This haze was visually significant and required an IOL exchange. To the knowledge of the authors this is the first report of this nature. The authors advise caution when using intracameral SF6 or C3F8 gas for repair of Descemets membrane detachment with this type of IOL.

Management of band keratopathy with excimer phototherapeutic keratectomy: visual, refractive, and symptomatic outcome.

PURPOSE: To report on the outcome of excimer phototherapeutic keratectomy (PTK) in the management of band keratopathy. METHODS: Analysis was performed on patients undergoing PTK for band keratopathy between January 1996 and December 1999. Patients were assessed as to whether the indication for PTK was for visual rehabilitation (visual group) or for ocular surface improvement (nonvisual group). Further data including pre- and postoperative best-corrected visual acuity, pre- and postoperative spherical equivalent (SE), and associated or previous ocular pathology were collected. RESULTS: A total of 45 eyes of 33 patients underwent PTK for band keratopathy. In the visual group, there were 33 eyes of 22 patients, and in the nonvisual group 12 eyes of 11 patients. The visual acuity was improved or unchanged in 18/33 eyes (55%) of the visual group, while there was loss of one or more lines of acuity in 15/33 (45%). Loss of acuity was attributed to other factors in 11/15 eyes. There was a significant myopic shift (P<0.5) from the mean preoperative SE of +1.42 D (SD+/-3.21 D) to the mean postoperative SE of +0.32 (SD+/-3.26 D). Of the eyes in the nonvisual group, 10/12 (83%) had significant improvement of symptoms. CONCLUSION: Excimer PTK is an effective procedure in the management of band keratopathy whether it is performed for visual rehabilitation or for ocular surface improvement to prevent erosions. Concurrent pathology is common and may limit the extent of visual improvement postoperatively. Factors associated with the myopic shift seen in this series may be epithelial remodelling, concurrent ocular pathology, or inaccuracy of preoperative refractive data.

Visual and symptomatic outcome of excimer phototherapeutic keratectomy (PTK) for corneal dystrophies.

PURPOSE: To determine the visual results and outcome of excimer laser phototherapeutic keratectomy (PTK) for corneal dystrophies. METHODS: Twenty-nine eyes of 19 patients who underwent excimer PTK for recurrent erosions and reduced vision due to corneal dystrophies, between February 1996 and July 1999, were reviewed. Data regarding the preoperative and postoperative best-corrected visual acuity (BCVA), change in spherical equivalent (SE), depth of excimer laser ablation, symptomatic relief, and incidence of recurrence were analysed by a retrospective chart review. RESULSTS: The range of follow-up was 12-48 months. Twenty-seven out of 29 eyes (93%) maintained or improved BCVA. All patients (17/17) were free of symptoms of recurrent erosions although two eyes needed repeat treatment to achieve this. In those eyes undergoing PTK for reduced vision, there was a trend towards a hyperopic shift postoperatively but this was not statistically significant. Five eyes showed recurrence of the dystrophy (Reis-Bücklers (one eye), Lattice (two eyes), and Granular (two eyes)) that required repeat treatment. Two of these eyes required a single repeat PTK procedure, and three eyes underwent three repeat treatments. There were no major complications during the follow-up period. CONCLUSIONS: Excimer PTK is a safe and effective procedure for relieving symptoms of recurrent erosions and improving visual acuity in patients with corneal dystrophies. Optimal visual results are achieved when treating more anterior disease. Multiple treatments are possible without significant detrimental effects for those patients with recurrence of their dystrophy.

Does the shared epitope genotype influence either the susceptibility to or the phenotype of corneal melting?

PURPOSE: To investigate the role of the shared epitope alleles in determining susceptibility to and the phenotype of corneal melting in patients with rheumatoid arthritis (RA). METHODS: The HLA class 1 and 2 genotype was determined for 17 patients with rheumatoid-associated comeal melting by the phototyping method. HLA-DR4 subtyping was performed by PCR sequence-based typing. The frequency of all the shared epitope alleles and, in particular, of the higher-risk *0401 and *0404 alleles, was compared with healthy controls and unrelated RA patients, with and without extra-articular manifestations. A comparison was also made between the shared epitope genotype of the corneal melt patients and local, ocular disease characteristics. RESULTS: Thirteen (76%) patients with corneal melt possessed at least one shared epitope allele and 5 (29%) possessed two alleles. The dominant alleles were variants of the DR4 family, notably the *0401, *0404 and *0408 alleles. Both the allele frequency and a double dose of shared epitope alleles were more common in the three RA patient groups than in the healthy, control group (p < 0.005). Although the frequency of the higher-risk alleles was similar in the three RA patient group, a trend existed for a double dose of higher-risk alleles to be more common in the patients with either corneal melt or other extra-articular manifestations (p > 0.2). No association was found between the number or type of shared epitope alleles and any of the ocular disease characteristics studied. CONCLUSIONS: The results of this study suggest that the shared epitope alleles do not influence the ocular disease phenotype of corneal melt in RA patients. Shared epitope determination of RA patients may help to identify those susceptible to either corneal melt or other extra-articular disease. RA patients with a double dose of higher-risk alleles may have an increased risk of corneal melt.

No strong association between alleles of tumour necrosis factor alpha and interleukin-1 receptor antagonist and corneal melting associated with systemic vasculitis.

AIMS: To investigate polymorphism within the tumour necrosis factor alpha (TNF-alpha) promoter region and within the interleukin-1 receptor antagonist (IL-1Ra) gene in a group of patients with vasculitis associated corneal melting. METHODS: The polymorphic regions at position -308 on the TNF-alpha promoter region and in intron 2 of the IL-1Ra gene were amplified by the polymerase chain reaction (PCR). The resultant products were separated by electrophoresis on agarose gels and visualised by ethidium bromide staining. Genotype and allele frequencies for the 20 patients were compared with healthy controls from the same geographical area. RESULTS: The allele frequencies in the patient and control groups respectively for the TNF-alpha and IL-1Ra sites studied were as follows: TNF1, 82.5% and 80.2%; TNF2, 17.5% and 19.8%; IL-1Ra*1, 82. 5% and 78.3%; IL-1Ra*2, 15% and 20%; IL-1Ra*3 2.5% and 1.5%. Although there was a trend for the IL1Ra*2 allele to be more common in the control group, no allele was found to have a statistically significantly association with the patient group: TNF1 p = 0.89; TNF2 p = 0.89; IL-1Ra*1 p = 0.65; IL-1Ra*2 p = 0.68; IL-1Ra*3 p= 0. 50. CONCLUSIONS: The results suggest that the polymorphic alleles of TNF-alpha and IL-1Ra studied play little or no part in the susceptibility to corneal melting among these patients with systemic vasculitis.

Incidence of corneal melting in association with systemic disease in the Yorkshire Region, 1995-7.

AIMS: To estimate the incidence of corneal melting or necrotising keratitis in association with systemic disease in the Yorkshire Region and to determine the type and duration of the systemic association. METHODS: In a prospective study, vigorous attempts were made to identify all patients presenting with newly diagnosed corneal melting over a 3 year period. RESULTS: 27 patients were identified during the study period. Rheumatoid arthritis and Wegener's granulomatosis were the most common disease associations. Corneal melting was a late complication of rheumatoid arthritis, but usually occurred during early and overt systemic disease in patients with Wegener's granulomatosis. CONCLUSION: The annual incidence of corneal melting in the Yorkshire Region is 3.01/million/year (95% CI = 0.7-9.6).

Dark adaptation in early primary biliary cirrhosis.

BACKGROUND: The role of vitamin A in early primary biliary cirrhosis (PBC) remains uncertain. METHODS: We assessed dark adaptation and assayed vitamin-A-related compounds in 10 patients with early PBC and a group of age- and sex-matched controls. RESULTS: In patients compared with controls: (i) mean final light threshold value was 11.8% greater (p < 0.004), (ii) time taken to see the first light stimulus was longer (2.8 +/- 0.6 vs 1.4 +/- 0.2 min, mean +/- SEM; p < 0.03) and (iii) sensitivity to light stimuli was impaired after 6 min in the dark (p < 0.03). Three patients had an abnormal final light threshold despite receiving regular vitamin A; two had a low serum vitamin A. Raised serum bilirubin and increased age were the most important determinants of impaired dark adaptation. CONCLUSIONS: Patients with early PBC have modestly impaired dark adaptation, despite standard vitamin A supplementation, although these changes may not have a significant effect on visual function. Vitamin A supplementation should be recommended for older patients with jaundice, but its effect should be carefully monitored.

Corneal perforation and decompensation after automated lamellar keratoplasty for hyperopia.

We describe a case of corneal perforation and decompensation after automated lamellar keratoplasty (ALK) in a middle-aged hyperopic man who had had unsuccessful holmium laser thermokeratoplasty. The corneal decompensation responded to gluing and application of a bandage contact lens but despite treatment, the corneal flap remained precariously poised with a localized area of thinning that is predisposed to future perforation and decompensation. This case highlights the potential for serious complications and subsequent visual morbidity after ALK.

Effect of intraocular lens fixation on acute intraocular pressure rise after neodymium-YAG laser capsulotomy.

Neodymium-YAG laser posterior capsulotomy is associated in some cases with an acute rise in the intraocular pressure (IOP), possibly caused by blockage of the trabecular meshwork by debris. To test the hypothesis that the IOP rise is preventable if fixation of the intraocular lens (IOL) in the capsular bag is ensured, we conducted a study comparing IOP changes at 1, 2, 3 and 24 hours after Nd:YAG capsulotomy between eyes with capsular bag-fixated, one haptic in the bag (haptic in/out) and cillary sulcus-fixated IOLs. Analysis of variance for repeated measures showed that after capsulotomy there were significant increases in IOP from baseline (p < 0.05) in both the sulcus-fixated (1, 2 and 3 hours) and haptic in/out groups (2 and 3 hours), while IOPs in the bag-fixated group did not show any significant increase. The increases in IOP in the sulcus-fixated group at 1, 2 and 3 hours after capsulotomy were significantly higher than the IOP changes at the corresponding periods in the other two groups (Kruskal-Wallis test, p < 0.01). The mean maximum IOP rise in the sulcus-fixated group (11.33 +/- 7.85 mmHg) was significantly higher than that in the haptic in/out group (3.89 +/- 7.14 mmHg) and the bag-fixated group (1.10 +/- 2.71 mmHg), while there was no difference between the latter two groups. In 57.5% of the sulcus-fixated group, 5% of the haptic in/out group and none of the eyes of the bag-fixated group the IOP rise was more than 10 mmHg. A significantly larger proportion of sulcus-fixated eyes had anterior chamber cells and capsular debris after capsulotomy (chi 2 test, p < 0.001). In the haptic in/out group significant correlation (-0.56, p = 0.009) between IOP rise at 1 hour and the percentage enclosure of the IOL by the anterior capsule was demonstrated. There was no significant difference in maximum IOP rise between glaucomatous and non-glaucomatous eyes (Mann-Whitney U-test, p = 0.49).

Visual outcome of childhood anterior perforating eye injuries: prognostic indicators.

Ninety-six cases of anterior globe perforation in children less than 16 years old, requiring surgical repair, were reviewed. Seventy-three patients were male and 23 female, with a mean age of 9 years 4 months. Perforation involving just the cornea was associated with a good visual prognosis unless: it involved the visual axis, resulting in corneal scarring and/or significant astigmatism (> 3.0 DS); it involved greater than one-quarter of corneal diameter; or there was non-compliance with spectacles/patching in patients younger than 8 years old. Injuries involving the lens in those younger than 8 years were associated with a far worse prognosis due to the problems of correcting aphakia. Surgical delay and method of injury did not affect prognosis. Some patients fail to re-attend and greater patient/parent education prior to discharge is recommended.

Aetiology of perforating eye injury.

This study addresses the aetiology of perforating ocular injury in childhood and possible preventive measures. Data have been collected from the case notes of 143 patients presenting over a 10 year period to a single ophthalmic unit. Injuries occurred most often in a domestic setting (34%) or with a child at play (19%) and showed an overall four to one ratio of boys to girls. Sports injuries accounted for 15% and assault for 8% of all injuries. A changing pattern of ocular injury is evident: road traffic accidents constituted 6% of injuries, compared with 31% in a similar study published in 1976. The role of litigation is discussed, particularly with regard to firearms, which accounted for 8% of injuries. It is concluded that the most important factor in the prevention of perforating ocular trauma is parental awareness, 53% of injuries occurring with the child in a domestic setting or at play.