Osman Çekiç

Incidence of keratoconus in subjects with vernal keratoconjunctivitis:: A videokeratographic study

PURPOSEnTo detect the incidence of keratoconus by videography in patients with vernal keratoconjunctivitis (VKC) and to evaluate the clinical characteristics of VKC associated with keratoconus.nnnDESIGNna prospective, cross-sectional (prevalence) study.nnnPARTICIPANTSnEighty-two consecutive subjects with the diagnosis of VKC.nnnMETHODSnBoth eyes of VKC subjects were investigated by videokeratography in comparison with slit-lamp biomicroscopy and keratometry. To detect keratoconus, corneal topography maps were examined with modified Robinowitz-McDonnell test.nnnMAIN OUTCOME MEASURESnIn this test, maps with central corneal power greater than 47.2 diopters and/or the inferosuperior asymmetry value greater than 1.4 were considered to have a keratoconus pattern. The findings of VKC were also recorded,nnnRESULTSnThe distribution of clinical forms of VKC were as follows: 46.34% mixed, 43.90% palpebral, and 9.76% limbal types. Twenty-six (31.7%) of 82 subjects had complications with keratopathy such as pseudo-genontoxon, punctate keratitis, and shield ulcer. Forty-four eyes (26.8%) were detected as keratoconus by quantitative evaluation of videokeratography maps. 14 eyes (8.5%) by biomicroscopy, and 30 eyes (18.3%) by keratometry. The increased incidence of keratoconus was associated with male gender, long-standing disease, mixed and palpebral forms, and advanced corneal lesions.nnnCONCLUSIONSnThe higher incidence of keratoconus in our study compared with the previous reports may result from early detection of mild keratoconus by interpretation of color-coded videokeratographic maps with a sensitive quantitative method.

Effect of cigarette smoking on copper, lead, and cadmium accumulation in human lens

AIM To identify cigarette smoking as a risk factor for development of cataract, to determine the importance of copper, lead, and cadmium in cataractogenesis, and to learn about any relation between those elements. METHODS Copper, lead, and cadmium concentrations were measured by atomic absorption spectrophotometry in 37 cataractous and nine normal human lenses. RESULTS All three element accumulations in lenses with cataract were statistically meaningful. Lenticular copper, lead, and cadmium were increased significantly with cigarette smoking. Cadmium had a positive correlation both with lead and copper in cataractous lenses. CONCLUSION The accumulation of copper, lead, and cadmium occurs in cataract. The probable source of cadmium in humans is cigarettes. Lenticular cadmium accumulation also increases copper and lead precipitation in the lens. Cigarette smoking might be cataractogenic.

Penetration of ofloxacin in human aqueous and vitreous humors following oral and topical administration.

Purpose: To determine aqueous and vitreous humor ofloxacin levels following oral and topical application of ofloxacin in patients with noninflamed cornea and intact crystalline lens, and to compare the drug levels provided by each route. Materials and Methods: Twenty‐six patients undergoing pars plana vitrectomy for various ocular pathologies were divided into two groups. Fourteen patients received two drops of 0.3% ophthalmic solution of ofloxacin every 30 minutes for 3 hours and every 60 minutes for the next 3 hours, and 12 patients received a single oral dose of 400 mg ofloxacin 8 hours before surgery. The aqueous and vitreous humor samples were simultaneously collected after oral or topical administration during pars plana vitrectomy to assess penetration of the drug. Samples were assayed for ofloxacin concentrations by a previously described method using high‐performance liquid chromatography. Results: The aqueous and vitreous humor levels of ofloxacin were 1.54 ± 0.27 μg/mL (mean ± standard error) and 1.77 ± 0.24 μg/mL after oral and 1.44 ± 0.24 μg/mL and 0.37 ± 0.05 μg/mL after topical ofloxacin administration, respectively. Aqueous humor levels were not statistically different following oral or topical administration (P > 0.8). However, vitreous level of the drug after oral administration was significantly higher than that after topical administration (P < 0.001). Conclusion: Ocular bioavailability of ofloxacin in aqueous humor after oral and topical administration is similar when the drug is applied as described. Penetration of ofloxacin into vitreous humor is less than that into aqueous humor following topical application. The aqueous humor levels of ofloxacin via both routes and the vitreous level of the drug after oral route exceed the minimum inhibitory concentrations for certain bacterial species that frequently cause intraocular infection.

Human aqueous and vitreous humour levels of ciprofloxacin following oral and topical administration

Purpose To assess aqueous and vitreous humour ciprofloxacin concentrations following oral and topical administration of ciprofloxacin in patients with non-inflamed cornea and an intact crystalline lens, and to compare the concentrations of the drug given by either route.Methods In this prospective study, 34 patients undergoing pars plana vitrectomy for various ocular pathologies were divided into two groups. Eighteen patients received 2 drops of 0.3% ophthalmic solution of ciprofloxacin every 30 min for 3 h and then every 60 min for the next 3 h, and 16 patients received a single oral dose of 1000 mg ciprofloxacin 6 h before surgery. The aqueous and vitreous humour samples were simultaneously harvested after oral or topical administration during pars plana vitrectomy to assess penetration of the drug. These samples were assayed for ciprofloxacin concentrations by a method described previously by us using high-performance liquid chromatography.Results The aqueous and vitreous humour levels of ciprofloxacin were 0.59 ± 0.06 μg/ml (mean ± SEM) and 0.64 ± 0.06 μg/ml after oral and 0.44 ± 0.07 μg/ml and 0.22 ± 0.04 μg/ml after topical ciprofloxacin administration, respectively. Aqueous humour levels were not statistically significantly different following oral and topical administration (p = 0.069). However, the vitreous level of the drug after oral administration was significantly higher than that after topical administration (p<0.001).Conclusion Ocular bioavailability of ciprofloxacin in aqueous humour following oral and topical administration is found to be similar when the drug was applied as described above. Penetration of ciprofloxacin into vitreous humour is less than that into aqueous humour after topical administration.

Changes in Anterior Chamber Depth and Intraocular Pressure After Phacoemulsification and Posterior Chamber Intraocular Lens Implantation

BACKGROUND AND OBJECTIVEnTo determine anterior chamber depth (ACD) and intraocular pressure (IOP) following uncomplicated cataract extraction with phacoemulsification and posterior chamber intraocular lens (IOL) implantation.nnnPATIENTS AND METHODSnThe ACDs and IOPs of 56 patients were prospectively evaluated after phacoemulsification and IOL implantation. Measurements of ACD were performed using ultrasonography and measurements of IOP were performed using a Goldmann applanation tonometer preoperatively and at 1 week and 1, 3, 6, and 9 months postoperatively.nnnRESULTSnThe mean IOP had decreased and the mean ACD had increased significantly by 1 month postoperatively (P < .03 and P < .01, respectively). Between 1 and 3 months, a significant increase in ACD (P < .05) and decrease in IOP (P < .01) was also observed. The ACD peaked (3.51 +/- 0.45 mm) and the IOP reached its lowest value (10.05 +/- 2.23 mm Hg) at 3 months postoperatively. The reduction in IOP and increase in ACD remained significant during the follow-up period, compared with the preoperative values.nnnCONCLUSIONnThese results suggest that increases in ACD and decreases in IOP occur in selected patients after uncomplicated cataract extraction by phacoemulsification with IOL implantation.

An Outbreak of Early-Onset Endophthalmitis Caused by Fusarium Species following Cataract Surgery

Purpose: This study aimed to report an outbreak of early-onset endophthalmitis caused by Fusarium species following cataract surgery. Methods: The study was designed retrospectively to review microbiologic and medical records of eight cases of endophthalmitis caused by Fusarium species after cataract surgery performed in the same operating room and on the same date by different surgeons at Beyoğlu Eye Training and Research Hospital in Istanbul, Turkey. Seven patients had phacoemulsification and intraocular lens implantation surgery. Intracapsular cataract extraction was performed in one patient. The common feature of these surgeries was the use of intracameral injections of cefuroxime (1u2009mg in 0.1-ml balanced salt solution–BSS) solutions, which were preoperatively prepared from the same BSS bottle. Results: The duration between cataract surgery and the diagnosis of endophthalmitis was four days. Aqueous and vitreous specimens obtained from the patients grew fungus colonies that were identified according to their morphologic features and considered to be Fusarium solani. All patients underwent multiple vitrectomies with silicone oil injections. Patients were given local and systemic antifungal agents (amphotericin B and voriconazole). One patient with corneal involvement underwent evisceration despite a variety of treatments. One patient with unregulated diabetes was prephthisic without recurrence of infection. The final visual acuity of patients was between light perception and 20/100. Conclusion: Fusarium should be considered in the differential diagnosis of early-onset endophthalmitis after cataract surgery. An aggressive treatment with local and systemic antifungal agents and multiple vitrectomies with silicone oil injection is helpful in the management of postoperative early-onset Fusarium endophthalmitis. In the prevention of such outbreaks, it is important to use solutions prepared differently for each patient.

Manual tunnel incision extracapsular cataract extraction using the sandwich technique

Small incision extracapsular cataract extraction (ECCE) using the sandwich technique is described. After capsulorhexis, hydrodissection, and hydrodelineation, the endonucleus is moved into the anterior chamber and extracted by sandwiching it between the irrigating vectis and iris spatula. In a series of 37 eyes, most achieved a best corrected visual acuity of 5/10 or better postoperatively. Complications were posterior capsule rupture, vitreous loss, and transient corneal edema. Small incision ECCE using the sandwich technique is safe, easy, and does not require expensive instrumentation.

Penetration of ofloxacin and ciprofloxacin in Aqueous humor after topical administration

BACKGROUND AND OBJECTIVEnTo compare the aqueous humor levels of 0.3% ofloxacin and 0.3% ciprofloxacin containing eyedrops in patients with healthy cornea.nnnPATIENTS AND METHODSnFifty patients with cataract were randomly assigned to have 0.3% ofloxacin containing eyedrop (25 patients) or 0.3% ciprofloxacin containing eyedrop (25 patients). Both drugs were repetitively instilled to each patient for 6 hours before the surgery. Aqueous samples were collected after penetrating the anterior chamber during cataract extraction and assayed by high-performance liquid chromatography method.nnnRESULTSnThe aqueous humor level of ofloxacin (1.43 +/- 0.26 microg/ml, mean +/- SEM) was significantly higher than that of ciprofloxacin (0.35 +/- 0.07 microg/ml) following the topical application (P < .0002).nnnCONCLUSIONnAqueous humor penetration of topical ofloxacin is about 4 times higher than that of topical ciprofloxacin when the drugs are applied as described above.

Comparison of conventional and torsional mode (OZil) phacoemulsification: randomized prospective clinical study

Purpose To compare the amount of intraoperative energy used during conventional and torsional phacoemulsification surgery and investigate the changes in corneal endothelial cell density. Methods In this study, a total of 100 eyes in patients with age-related cataract (mean age 68.9 years) were included. Patients were randomly allocated into conventional (group 1) or torsional (OZil, group 2) phacoemulsification. Mean nuclear grade made according to Lens Opacities Classification System II was not different in the 2 groups. Total ultrasound time (USTT), cumulative dissipated energy (CDE), and the percent of total equivalent power in position 3 (%USTEPiP3) were compared between the 2 groups. Results There were 47 eyes in group 1 and 53 eyes in group 2. Patient age and sex were matched between the 2 groups (p=0.49, p=0.08). Mean USTT was 1.6±1.1 minutes (m) in group 1 and 1.5 ± 0.9 m in group 2 (p=0.55). Average CDE was 29.9±16.9 in group 1 and 25.2±19.1 in group 2 (p=0.20). Mean %USTEPiP3 was 27.0%±8.5% in group 1; however, it was 22.4%±6.6% in group 2 (p=0.003). At the first postoperative day, mean corneal edema was graded as 0.25±0.5 in group 1 and 0.18 ± 0.4 in group 2 (p=0.47). At the first postoperative week, it was found to be 0.02±0.15 in group 1 and 0.03±0.27 in group 2 (p=0.71). ECD loss was 6.7%±3.3% in group 1 and 4.2%±5.7% in group 2 (p=0.56). Conclusions No statistically significant difference was found between conventional and torsional phacoemulsification with respect to USTT and CDE. Torsional mode led to a significant reduction in US power in footswitch position 3. Torsional mode also appears to be associated with less loss of ECD

Aqueous humour levels of topically applied ciprofloxacin and ofloxacin in the same subjects

Purpose To evaluate aqueous humour levels of topical 0.3% ciprofloxacin and 0.3% ofloxacin in the same subjects.Methods Thirty-two bilateral cataractous patients received topical 0.3% ciprofloxacin in one eye and 0.3% ofloxacin in the other eye before each cataract extraction. Eyedrops were repetitively instilled for 6 h. Aqueous humour samples were collected and assayed for drug concentrations by a method described originally by us using high-performance liquid chromatography.Results Mean aqueous ciprofloxacin and ofloxacin levels were 0.33 ± 0.04 μg/ml (mean ± SEM) and 1.34 ± 0.14 μg/ml respectively (p<0.0001).Conclusion Ofloxacin level in the aqueous humour is 4 times higher than that of ciprofloxacin in the same subjects.