Comparison of Optical Quality Between Two Intraocular Lenses Using Double-Pass Based Optical Quality Analysis System

PURPOSE: To compare postoperative optical qualities between two types of 1-piece aspheric intraocular lenses using the double-pass technique. METHODS: Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), and spherical equivalent were evaluated in the subject groups; the first which included 25 eyes implanted with Tecnis(R) ZCB00 and the second which included 16 eyes implanted with Acrysof(R) IQ SN60WF. In addition, modulation transfer function (MTF) cut-off, Strehl ratio, and objective scattering index (OSI) were measured 6 months after cataract surgery in the 2 subject groups using Optical Quality Analysis System (OQAS, Visiometrics S.L., Terrasa, Barcelona, Spain) which is based on the double-pass technique. RESULTS: There were no significant differences in the spherical equivalent, UCVA, BCVA, and OSI between the 2 groups. However, both the MTF cut-off, and Strehl ratio showed statistically significant differences. The MTF cut-off (28.0 +/- 7.79 vs. 20.4 +/- 9.51 c/deg, p = 0.025) and Strehl ratio (0.14 +/- 0.04 vs. 0.12 +/- 0.05, p = 0.042) were higher in the Tecnis(R) ZCB00-implanted group. CONCLUSIONS: The difference in characteristics of intraocular lenses subtly affects the vision quality as measured by values such as MTF cut-off and Strehl ratio after cataract surgery. OQAS based on the double-pass technique is considered useful in more objective estimates of the real retinal image quality after cataract surgery which is difficult to explain simply by measuring visual acuity.

A Case of Acute Nonarteritic Anterior Ischemic Optic Neuropathy in Patient on Hemodialysis

PURPOSE: To report a case of non-arteritic anterior ischemic optic neuropathy (NAION) in a patient on hemodialysis. CASE SUMMARY: A 59-year-old female undergoing intravenous hemodialysis developed sudden blurred vision for 2 days. Chronic hypotension and anemia may have been persisted for approximately 6 months before the onset of symptoms. Her corrected visual acuity in both eyes was 0.7 and visual field test showed superior arcuate defect in the left eye. Fundus photography showed inferonasal optic disc swelling and fluorescein angiography revealed hyperfluorescence of the disc in the late phase which was probably attributable to NAION. After 3 weeks, corrected visual acuity was 0.7 in the left eye and fundoscopic finding of the left eye was improved. CONCLUSIONS: Hemodialysis can cause a hypotensive event and anemia which may be associated with NAION. Avoiding acute hypotension and anemia should be advised to prevent development of NAION in dialysis patients.

Orbital Cellulitis Following Strabismus Surgery

PURPOSE: To report a case of sudden orbital cellulitis presenting 2 weeks after strabismus surgery in a patient who had previously undergone retinal surgery for rhegmatogenous retinal detachment. CASE SUMMARY: A 45-year-old male visited the ophthalmology clinic with a 3-day history of left eye pain and lid swelling which suddenly developed 2 weeks after left lateral rectus muscle recession surgery for secondary sensory exotropia. The patient had undergone trans pars plana vitrectomy twice, scleral encircling, oil injection and removal for rhegmatogenous retinal detachment 1.3 years prior. His best corrected visual acuity was 0.2 in his left eye and physical examination revealed eyelid edema, chemosis, and subconjunctival hemorrhage of the left eye. The next day, eye movements were moderately restricted. Computed tomography scanning with contrast enhancement demonstrated diffuse periorbital soft tissue swelling and enhanced fat stranding suggesting left orbital cellulitis. The patient was hospitalized with intravenous broad spectrum antibiotics. He was discharged after a 5-day course of intravenous antibiotic treatment, but readmitted for symptom aggravation and purulent discharge from the left conjunctival fornix. Culture of conjunctival fornices revealed penicillin-resistant staphylococcus aureus. Intravenous anitibiotics were maintained for 11 days additionally and left eye swelling, tenderness and ocular movement restrictions were improved. The patient was discharged from the hospital with a best corrected visual acuity of 0.2.

Effect of Preoperative Crystalline Lens Rise on Vaulting after Implantable Collamer Lens Implantation

PURPOSE: To evaluate the parameters affecting vaulting and correlation between preoperative crystalline lens rise and vaulting after implantable collamer lense (ICL) implantation. METHODS: A total of 53 eyes of 34 patients who underwent ICL implantation were examined retrospectively. White-to-white (WTW) and anterior chamber depth (ACD) were obtained from scanning topography (ORB scan) before surgery. Preoperative crystalline lens rise (CLR) and vaulting at 6 months after ICL implantation were measured using anterior segment optic coherence tomography (AS-OCT). Multiple regression analysis was performed to evaluate the factors affecting central vaulting. RESULTS: The mean preoperative crystalline lens rise was -120 +/- 219 microm, and mean central vaulting 6 months after surgery was 544 +/- 175 microm. Preoperative SE, WTW, ACD, and CLR were significantly correlated with vaulting at 6 months after surgery. With the use of meaningful variables, multiple regression analysis showed that CLR, WTW, ACD and SE, in that order of influence, had significant effects on vaulting and the multiple regression equation was obtained as follows: Vaulting (microm) = (160.913 x ACD (mm)) + (170.134 x WTW (mm)) + (-0.338 x CLR (microm)) + (-23.783 x SE (D)) - 2250.184. CONCLUSIONS: CLR had a stronger influence on vaulting after ICL implantation than the previously proven parameters: WTW, ACD, and SE. In addition to WTW, ACD and SE, CLR should also be considered a new criterion for estimating vaulting after ICL implantation.

A New Simple Technique for Removal of Subconjunctival Cyst under the Slit Lamp Microscope

PURPOSE: We present a new simple technique to remove subconjunctival cyst under the slit lamp microscope. CASE SUMMARY: A cotton swab was used to verify whether or not the cyst was freely movable under the conjunctiva. After topical anesthesia, we incised the conjunctiva near the cyst using a 30-gauge needle and extracted the cyst through the wound using forceps under the slit lamp microscope. Four cases of subconjunctival cyst were successfully removed with our new technique. During the average five month (2-10 month) follow-up period, there was no recurrence or procedure-related complications. CONCLUSIONS: Some subconjunctival cysts such as an epithelial inclusion cyst which is freely movable without attachment to surrounding tissues can be easily removed with a 30-gauge needle and forceps under the slit lamp microscope. This could be considered as the primary procedure instead of simple aspiration.