Staining of intraocular lenses with various dyes: a study of digital image analysis.

PURPOSE: To evaluate the interaction of various intraocular lens (IOL) materials with commonly used dyes. MATERIALS AND METHODS: One IOL of each of the five groups (polymethylmethacrylate, silicone, three-piece hydrophobic acrylic, single-piece hydrophobic acrylic and single-piece hydrophilic acrylic) was bathed in trypan blue 0.1%, fluorescein sodium 2% and indocyanine green (ICG) 0.5% for 15 min. Digital photographs of the IOLs were obtained prior to bathing and after the 15-min bath in each dye. The same IOLs were immersed in the same dye for another 15 min and digital images were reobtained to depict the 30-min dye uptake. New IOLs from the group that exhibited visible colour change after the 15-min bath were then bathed in twofold dilution and if there was still visible dye uptake, fourfold dilution was performed, repeating the 15-min bath and digital photography. The images were then processed using Adobe Photoshop 5.1 to get mean luminosity and red-green-blue values. These values were compared between the groups and the undyed control. Also, dye washout was observed in serum-containing vials. RESULTS: None of the polymethylmethacrylate, silicone and hydrophobic acrylic IOLs were stained with the dyes used. The only IOL material that changed colour was hydrophilic acrylic and did so with all dyes. The most marked colour change was with fluorescein sodium 2%, the least was with trypan blue 0.05%. Twofold dilution of trypan blue and fourfold dilutions of fluorescein sodium and ICG still stained the hydrophilic acrylic IOL; however, fourfold dilution of trypan blue did not cause a significant colour change. Trypan blue washed out within 6 h, while the IOL stained with ICG remained stained for longer than 24 h. COMMENT: Hydrophilic acrylic IOLs should be used with caution together with dyes since this material demonstrates marked dye uptake and washout may also take some time.

Colour Doppler assessment of blood flow in eyes with central retinal vein occlusion.

PURPOSE: To assess the blood flow changes in eyes with central retinal vein occlusion (CRVO) and compare these values with values of fellow eyes and eyes of normal subjects. METHODS: 25 eyes of 25 consecutive newly diagnosed patients with CRVO comprised the study group. Their fellow eyes and those of 25 healthy subjects were the control group. All patients underwent a complete ophthalmological examination. Eyes with CRVO were classified into two groups as non-ischaemic and ischaemic by fundus fluorescein angiography. Colour Doppler imaging was performed with a Toshiba Sonolayer SSH-140A and 7.5-MHz linear array probe. Maximum systolic velocity (V(max)), end-diastolic velocity (V(min)) and resistive index (R(i)) values were noted for each of the central retinal artery (CRA), central retinal vein (CRV) and ophthalmic artery (OA). These parameters were compared with those of the fellow eyes and both eyes of the control group. RESULTS: Mean ages were 63.55 and 61.45 years in the CRVO and control groups, respectively. Age and sex distributions were statistically identical in both groups. When we compared the eyes with CRVO to the control group, no statistically significant difference existed between the two groups with regard to the V(min) and R(i )values of the CRA and CRV. However, V(max ) values of the CRA and CRV were significantly lower in CRVO eyes when compared to the control group. The CRVO group and control group had similar V(max), V(min ) and R(i) values for the OA. Only the V(max) was significantly lower in the CRV in eyes with CRVO when compared to the unaffected fellow eyes. No statistically significant difference could be detected between any of the parameters of CRA, CRV and OA of the ischaemic and non-ischaemic CRVO groups. CONCLUSIONS: More data on broader series need to be obtained in order to decide on the practical use of colour Doppler imaging in the differentiation of ischaemic eyes from non-ischaemic eyes in CRVO.

Unilateral retinal vasculitis, branch retinal artery occlusion and subsequent retinal neovascularization in Crohn's disease.

PURPOSE: To report on a case of Crohn's disease and unilateral retinal vasculitis, branch retinal artery occlusion and subsequent retinal neovascularization. METHODS: We examined a 38-year-old woman with severe left visual loss and biopsy-proven Crohn's disease diagnosed four years prior to the ocular involvement. A Heidelberg scanning laser ophthalmoscope was used for fundus fluorescein angiography and indocyanine green angiography. Retinal neovascularization was detected during the follow-up. RESULTS: Successful regression of retinal neovascularization was achieved after argon green laser panretinal photocoagulation in addition to oral steroid and salazopyrine. CONCLUSION: Retinal vascular involvement is a rare ocular feature of Crohn's disease and may result in retinal neovascularization that may necessitate prompt laser photocoagulation.

Retinal breaks and rhegmatogenous retinal detachment in association with branch retinal vein occlusion.

BACKGROUND AND OBJECTIVE: To report the incidence and clinical characteristics of retinal breaks and/or rhegmatogenous retinal detachment (RRD) in patients with branch retinal vein occlusion (BRVO). PATIENTS AND METHODS: We reviewed the clinical records of 230 eyes of 214 patients with BRVO and identified eyes with retinal breaks and/or RRD. Patients had at least 6 months of follow-up. RESULTS: Seven of 230 eyes (3%) had retinal breaks and 3 eyes (1.3%) had RRD. One of the eyes with RRD had subclinical retinal detachment. All 7 eyes had ischemic disease documented by fluorescein angiography. Two of 7 eyes had concurrent retinal neovascularization. Four eyes with breaks, but without RRD, and the eye with subclinical RRD were managed by argon green laser. Two eyes with RRD were managed successfully with scleral buckling surgery and postoperative supplemental argon green laser. The mean follow-up period was 14.8 +/- 8.3 months. CONCLUSIONS: Patients with BRVO should be monitored closely for possible retinal break formation and RRD development.

Pseudoexfoliation and glaucoma in eyes with retinal vein occlusion.

PURPOSE: To evaluate pseudoexfoliation (PE) and pre-existent glaucoma in eyes with branch retinal vein occlusion (BRVO) and central retinal vein occlusion (CRVO). METHODS: Consecutive eyes with a diagnosis of BRVO (73 eyes of 70 patients) and CRVO (53 eyes of 49 patients) examined between July and December 1998 comprised the study eyes. Age-matched control group consisted of 384 eyes of 192 outpatients. The prevalence of PE and glaucoma were determined and appropriate statistical tests were performed. RESULTS: PE was present in six of 73 eyes with BRVO (8.2%), 11 of 53 eyes with CRVO (20.8%) and 20 of 384 control eyes (5.2%). Two of 73 eyes with BRVO (2.7%) and 10 of 53 eyes with CRVO (18.9%) had glaucoma. Compared with the control eyes, PE was significantly more common in eyes with CRVO and coexistent glaucoma was significantly more common both in eyes with CRVO and in eyes with BRVO. CONCLUSION: While glaucoma seems to be a risk factor both for BRVO and CRVO, PE is a likely risk factor for CRVO.

Monoscleral fixated lens implantation in eyes with partial loss of capsular or zonular support.

A technique is described in which a posterior chamber intraocular lens (IOL) is implanted in eyes with partial loss of posterior capsule or zonular support. The IOL's inferior haptic is placed over the residual capsule and the superior haptic is fixated to the ciliary sulcus with a polypropylene suture. In 17 eyes that had surgery using this technique, mean postoperative visual acuity was 20/25; complications included irregular pupil, iris capture, pupil block, hyphema, localized peripheral anterior synechia, IOL tilt, suture exposure, and cystoid macular edema.

Axial length and hyperopia in eyes with retinal vein occlusions.

We performed a prospective study in order to elucidate the predisposing role of axial length and hyperopia in retinal vein occlusions. The study group comprised 39 patients with unilateral central retinal vein occlusion (CRVO), 50 patients with unilateral branch retinal vein occlusion (BRVO), 13 patients with unilateral hemispheric retinal vein occlusion (HRVO) and 45 control eyes. The axial length of affected eyes was compared to fellow eyes and control eyes in each subgroup of patients with retinal vein occlusion. No statistical difference was noted for any of the subgroups (p > 0.05). Hyperopia was detected in 12 of 39 eyes (31%) with CRVO, 14 of 50 eyes (28%) with BRVO, 4 of 13 eyes (31%) with HRVO and 15 of 45 eyes (33%) in the control group. No statistically significant difference was discovered (p > 0.05). In the light of our study, we believe that axial length and hyperopia may not be risk factors in retinal vein occlusions, in contrast to common belief.