Tekin Yasar

Effect of superior and temporal clear corneal incisions on astigmatism after sutureless phacoemulsification

Purpose: To evaluate the effect of superior and temporal clear corneal incisions on astigmatism after sutureless, small incision phacoemulsification. Setting: World Eye Hospital, Istanbul, Turkey. Methods: This prospective study evaluated 40 eyes of 20 patients with cataract having bilateral, sutureless, small incision phacoemulsification by the same surgeon. A superior clear corneal incision was used in all right eyes and a temporal clear corneal incision in all left eyes. Mean preoperative astigmatism was 0.63 diopter (D) ± 0.21 (SD) and 0.65 ± 0.20 D, respectively. Mean patient age was 66.45 years. Patients were examined preoperatively and 1 day, 1 week, and 1 and 3 months postoperatively. Results: Three months postoperatively, mean astigmatism was 1.60 ± 0.37 D in the superior incision group and 0.83 ± 0.19 D in the temporal incision group. Induced astigmatism calculated by vector analysis was 1.44 ± 0.31 D and 0.62 ± 0.28 D, respectively. The temporal incision group had significantly lower astigmatism at all follow‐ups (P = .000). Conclusion: Upper lid pressure on the superior corneal incisions led to fluctuating, against‐the‐rule astigmatism that was significantly higher than that induced by temporal incisions.

The Effect of Pterygium Surgery on Corneal Topography

OBJECTIVE The aim of this prospective randomized clinical study was to evaluate the effect of pterygium surgery on the corneal topography using a computerized corneal topography system. PATIENTS AND METHODS Computerized corneal topography was performed on 27 patients with primary pterygium before and after pterygium excision surgery. The topographical changes that occurred following surgery were evaluated using paired and unpaired two-tailed t-test and Pearson coefficient of correlation analyses. Simulated keratometric astigmatism at the central 3 mm and the total mean refractive powers of the whole cornea were measured before and after surgery. Following surgery, flattened or steepened corneal areas were determined. RESULTS Simulated keratometric astigmatism at 3 mm was found to be 2.30 +/- 2.08 D (0.2 - 7.63) preoperatively and 0.82 +/- 0.74 D (0.06 - 2.79) postoperatively. The difference between these two values was statistically significant (t = -3.46, P = 0.002). Total mean refractive power of the whole cornea was found to be 42.26 +/- 0.63 (40.80 - 43.64) preoperatively and 43.69 +/- 0.88 (41.50 - 44.90) postoperatively and the difference was 1.42 +/- 0.87. There was a statistically significant high difference (t = 28.36, P < 0.001). When preoperative and postoperative corneal topographies were compared, the whole cornea was found steeper at the postoperative period except a little region in the superior nasal quadrant. CONCLUSION We believe that corneal topographical changes caused by the pterygium are almost reversible after surgical treatment, and postoperatively the cornea becomes steeper.

Peribulbar Anesthesia: One Versus Two Injections

BACKGROUND AND OBJECTIVE The authors describe their prospective, randomized study of a single peribulbar injection into the junction of the lateral third and medial two thirds of the lower lid compared with the standard two-injection peribulbar technique. PATIENTS AND METHODS One hundred twenty patients undergoing elective intraocular surgery were randomly allocated to receive either one or two injections of a mixture of balanced salt solution, 2% lidocaine, 0.5% bupivacaine, and hyaluronidase. Preoperative akinesia was assessed following the injections. At the end of surgery, the patients were asked if they had experienced any pain or discomfort during surgery. RESULTS There was no significant difference in pain or globe akinesia between the two groups. CONCLUSION The single peribulbar injection was found to be as effective as the standard two-injection peribulbar technique.

BCG vaccination to prevent implantation of endometriosis: an experimental study in rats

To investigate whether BCG vaccination can prevent endometrial implantation in a rat model. Forty sexually mature virgin Wistar-Albino rats weighing 185-215g were randomly assigned (double-blind) to two groups. The first group (n=20) were injected with BCG 3 weeks before endometrial implantation to the eye. The second group (n=20) with BCG not injected before endometrial implantation was the control. Photobiomicroscopy observation was done weekly and 6 weeks post endometrial implantation all eyes were investigated histologically.Five implants grew in the anterior surface of the iris of the first (vaccinated) group and 17 in the second (control) group. The difference was statistically significant. Systemic prophylaxis with BCG can exert an inhibitory effect on endometrial transplantation.

Intraoperative Application of Mitomycin C in the Surgical Treatment of Pterygium

Purpose To investigate the effectiveness of intraoperative mitomycin C in pterygium surgery. Methods The effectiveness of intraoperatively administered mitomycin C and the occurrence of postoperative complications were evaluated in 17 patients with two recurrences of pterygium. The authors employed the “bare-sclera technique” and placed a sterile sponge soaked in a 0.02% mitomycin C solution intraoperatively in the episcleral space for 3 minutes. The control group (15 patients) underwent only surgical excision. Patients were followed for 21 to 30 months. Results The pterygium recurred in one (5.9%) of the 17 patients in group 1 and in six (40%) of the 15 controls. Statistical analysis using Fishers exact test showed a significant (p=0.027) reduction of recurrences of pterygium in the group treated intraoperatively with mitomycin C. No serious complications or side effects arose during the follow-up period. Conclusions Mitomycin C administered intraoperatively can be considered an effective treatment to improve the success rate after surgical excision.

Topiramate Induced Bilateral Angle-Closure Glaucoma: Low Dosage in a Short Time

PURPOSE The aim of this article is to create awareness among medical colleagues regarding the severe ophthalmic side effects associated with topiramate use. METHODS A case of severe acute bilateral angle closure glaucoma with visual blurring after oral topiramate therapy. RESULTS This case was successfully managed by discontinuing topiramate and by starting anti-glaucoma medication. Intraocular pressure, acute transient myopia, and anterior chamber depth were normalized. CONCLUSIONS It is important for clinicians to recognize these conditions and educate patients about these serious adverse effects when prescribing topiramate.

The Effect of Altitude on Radial Keratotomy

The authors analyzed refractive results of patients who underwent radial keratotomy (RK) at sea level and high altitude and evaluated the effects of the altitude. A total of 102 eyes undergoing RK procedures performed in two clinical centers having different altitude were analyzed. The results compared between subjects who had undergone RK at sea level (Istanbul/Turkey) and at an altitude of 5750 feet (Van/Turkey) were compared. Subjects were 19-42 years old with myopia from -4.00 to -12.00 diopters (D). The average preoperative spherical equivalent cycloplegic refractions (SECR) were -8.01 +/- 1.86 D and -6.99 +/- 2.15 D in the Istanbul and Van groups, respectively. These were divided into subgroups according to myopia degree and number of incisions and optic zone size. The RK procedures were performed by the same surgeon with diamond blade in standard Russian style. The average changes in SECR were 5.09 +/- 1.29 D and 6.50 +/- 2.24 D in subjects who had undergone RK at sea level and at 5750 feet, respectively. There was a significant difference between the subgroups (P < 0.0002). This difference was especially higher in the high myopia subgroups. Additionally, we obtained a partial relation between increase of RK incision number and SECR change at high altitude but not at sea level. No notable regression and progression were seen in the 3 months of follow-up at high altitude. These results support hypotheses suggesting both corneal hypoxic expansion in the area of RK incisions, which may lead to central corneal flattening, and barometric pressure directly altering corneal shape, which is responsible for the hyperopic shift induced by altitude. Ophthalmologists performing RK surgery at high altitude had better consider redesigning their RK nomograms in light of these findings. However, when the nomogram used at sea level was used at high altitude, the subjects became hyperopic.

MRI-Induced Migration of Retained Metallic Foreign Body in the Eye

A 50-year-old man presented to the out-patient clinic because of a sudden pain in his left eye just after lumbal magnetic resonance imaging (MRI) was started. Biomicroscopic examination of the left eye revealed the inferior anterior chamber angle including a foreign body and the superior anterior chamber angle including the iris portion, into which the foreign body had been stuck prior to the MRI examination. His history revealed an accidental penetrating eye trauma of the shotgun pellet of 28 years ago. The foreign body was easily removed using a forceps intraoperatively. The foreign body was defined as a metallic foreign body postoperatively.

Conjunctival myxoma: a clinicopathologic report.

A conjunctival myxoma was identified in a specimen obtained from a 45-year-old woman via excisional biopsy. The patient presented with a slowly growing painless epibulbar mass. The paucicellular tumor included stellate and spindle-shaped cells, mast cells, and dilated lymphatic channels embedded in a loose collagenous matrix. The differential diagnosis of conjunctival myxoma should include tumors that have myxoid patterns and richly myxoid malignant neoplasms.

Effects of 0.5% and 0.25% apraclonidine on postoperative intraocular hypertension after cataract extraction

Purpose We conducted a double-masked, prospective study to evaluate the effect of 0.5% and 0.25% apraclonidine on postoperative intraocular pressure (IOP) in patients undergoing extracapsular cataract extraction (ECCE) with intraocular lens (IOL) implantation. Methods Fifty-four patients scheduled for ECCE were randomly divided into three groups of 18. The first group received one drop of 0.50% apraclonidine topically one hour before surgery and immediately after the end of the procedure. The second group received the same regimen but with 0.25% apraclonidine. The third group received artificial tears as the control group. IOP was measured 12 h preoperatively and 6 and 24 h postoperatively. All the measurements were made using the same Goldmann applanation tonometer by the same surgeon who did not know to which group the patient belonged. Results Preoperative mean IOP was 13.66 ± 2.76 mmHg in the first group, 14.27 ± 2.24 mmHg in the second and 14.5 ± 1.34 mmHg in the control group. The differences were not significant (p=0.398). Mean IOP at the early postoperative visit (6 h) was significantly lower in the first group (17.44 ± 4.95 mmHg) than the second (21.78 ± 7.19 mmHg) and the control group (24.55 ± 5.65 mmHg) (p<0.001). Mean postoperative IOP at 24 h was again significantly lower in the first group (14.33 ± 3.75 mmHg) than the second (17.11 ± 4.16 mmHg) and the control group (19.61 ± 3.20 mmHg) (p<0.001). Conclusions Our findings indicate that topical 0.5% apraclonidine controlled early postoperative intraocular hypertension after cataract extraction without any side effects, while the 0.25% drops were not effective.