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Y A Akova

Publications and source records attributed to Y A Akova.

At least 19 recordsLinked to original sources
PubMed2006

Relationship between optokinetic nystagmus response and recognition visual acuity.

PURPOSE: The aim of this study was to investigate the relation between recognition visual acuity (RVA) and optokinetic nystagmus (OKN) response exhibited to different bar sizes with varying contrast. METHODS: OKN testing was performed in 52 children aged between 3 and 11 years. The children were evaluated in two groups according to their RVA. Group I consisted of 22 eyes with RVA equal to or better than 0.1 logMAR units. Group II consisted of 30 eyes with RVA 0.2-1 logMAR units. Each subject was seated 60 cm from the screen of Ophthimus device, and was exposed to consecutive black and white stripes of seven different spatial frequencies (0.08-1.6 cycle/degree). The narrowest bar that elicited OKN was identified, and then the OKN contrast threshold at this bar size was established. RESULTS: Twenty-one of the 22 eyes in Group I, and 26 of the 30 eyes in Group II exhibited 1.6 cycle/degree spatial frequency (P=0.287). In Group II, 88.9% of the 18 eyes with RVA 0.2-0.5 logMAR responded at this maximum spatial frequency, whereas the corresponding figure for the 12 eyes with RVA 0.6-1 logMAR was 83.3% (P=0.531). Contrast sensitivity (CS) significantly changed with age in Group I (P=0.006). When the eyes that responded at maximum spatial frequency in the two groups were compared, the mean CS in Group II was significantly lower than that in Group I (P=0.005). CONCLUSIONS: The results indicate no relation between spatial frequency threshold for OKN response and RVA in children. However, the children with RVA deficits had significantly lower CS.

Age Factors↗
PubMed2006

Decision-making in second-eye cataract surgery: can presence of Pulfrich phenomenon help?

PURPOSE: To determine whether testing for the Pulfrich phenomenon (PP) can be used as a tool to assess the need for and optimal timing of second-eye cataract surgery. METHODS: A total of 61 patients with logMAR 0 visual acuity (VA) after cataract surgery in one eye and logMAR 0.2-0.7 VA in the other eye were tested for PP using a computer-generated oscillating target at Baskent University Hospital. Only patients who had no ophthalmologic or systemic problem that could cause PP were included. In all, 15 normal patients with logMAR 0 VA in both eyes served as controls. The main outcome measures were presence and magnitude (measured by neutral density filters) of PP and presence of complaints related to binocular vision. RESULTS: Of the 61 patients, 36 (59%) and none of the controls were PP (+) (P<0.001). A total of 27 (75%) of the PP (+) patients had logMAR 0.7-0.4 VA, and nine (25%) had logMAR 0.3-0.2 VA (P=0.01). In all, 16 patients (all PP (+)) had developed binocular vision-related complaints since cataract surgery. The mean PP magnitude in these cases was significantly greater than the mean for the 20 patients without complaints (1.2+/-0.5 vs0.6+/-0.4 log units, respectively; P<0.001). There was no significant difference between the mean VA in the complaint (+) and complaint (-) subgroups (P=0.213). CONCLUSION: PP testing may detect binocular visual dysfunction after first-eye cataract surgery; thus, it could help assess the need for second-eye cataract surgery on this basis.

Adult↗
PubMed2006

[Hemicentral retinal artery occlusion associated with moyamoya syndrome].

Moyamoya syndrome is a rare cerebrovascular disorder characterized by bilateral progressive supraclinoidal stenosis or occlusion of the internal carotid artery and development of collateral vessels in the lenticulostriate region. The syndrome manifests itself in association with another disease or other clinical symptoms. We present the case of a 12-year-old girl with hemicentral retinal artery occlusion due to moyamoya syndrome associated with clinical and laboratory findings of presumed systemic lupus erythematosus.

Child↗
PubMed2006

Opportunistic posterior uveal infections in renal transplant patients.

AIMS: To describe the cases of opportunistic posterior uveal infection diagnosed in renal transplant recipients at a single center over a 10-year period. METHODS: The study involved 1156 patients who underwent renal transplantation. Five of the recipients were diagnosed with posterior uveal infection. The specific diagnoses were acute retinal necrosis (two cases), cytomegalovirus retinitis (one case), nocardial chorioretinitis (one case), or tuberculoid granuloma (one case). RESULTS: The five patients were aged 27 to 55 years, and the interval from renal transplantation to uveal infection ranged from 7 months to 16 years. All patients were receiving immunosuppressive treatment at the time of the posterior uveal infection. Acute retinal necrosis was diagnosed in cases I and II at 2 and 3 years after transplantation, respectively. In both cases, fundus examination revealed moderate vitritis and yellow-white lesions representing confluent retinitis. In case III (cytomegalovirus retinitis), 7 months after transplantation the patient developed extensive hemorrhage and confluent white exudates, periphlebitis, and perivascular sheathing in the right eye. In case IV, culture of a fine-needle aspirate from a well-demarcated, white-yellow, elevated choroidal lesion in the superotemporal region of the macula revealed nocardial infection. Fundus examination of the right eye of case V revealed a small, hypopigmented choroidal lesion superior to the optic disc. The lesion was identified as a choroidal tuberculoid granuloma. CONCLUSIONS: Opportunistic chorioretinal infections can occur at any time after renal transplantation. So it is important that every kidney recipient undergo regular ophthalmic examinations throughout his or her lifetime.

Adult↗
PubMed2006

[Papilloedema and brain abscess associated with isolated left superior vena cava draining in to the left atrium].

BACKGROUND: Papilloedema and brain abscess associated with persistent left superior vena cava draining into the left atrium without sinus coronarius and atrium septum defect is rare and until now in only few cases have been reported. PATIENT: A 12 year-old girl was admitted because she had suffered from headache and blurred vision for 2 weeks. Fundus examination revealed papilloedema with peripapillary intraretinal haemorrhages. Pupillary reaction to light was normal. An afferent pupillary defect was negative. Neurological examination was without any focal neurological signs. Cerebral magnetic resonance imaging showed the characteristic features of a brain abscess in the left frontal lobe (3.5 x 3.0 x 2.8). Cardiological examination showed the presence of an isolated left superior vena cava draining into the left atrium in the absence of coronary sinus and atrial septum defect. CONCLUSION: Congenital heart disease such as LSVC is rare. The association of LSVC with papilloedema and brain abscess is very rarely seen. However, the complications of LSVC can be life-threatening. Therefore in children with papilloedema, intraocular and intraorbital reasons as well as congenital heart disease as the underlying reason should be included in the differential diagnosis.

Brain Abscess↗
PubMed2005

Comparison of additional intraocular pressure-lowering effects of latanoprost vs brimonidine in primary open-angle glaucoma patients with intraocular pressure uncontrolled by timolol-dorzolamide combination.

PURPOSE: To compare the additive intraocular pressure (IOP)-lowering effects of latanoprost 0.005% and brimonidine 0.2% in primary open-angle glaucoma (POAG) patients uncontrolled on fixed combination of timolol 0.5% and dorzolamide 2% (TDC) alone. METHODS: In all, 80 eyes of 80 POAG patients with IOP inadequately controlled by TDC were randomly assigned to receive either latanoprost 0.005% or brimonidine 0.2%. IOP measurements were recorded at 1000 (peak effect) and 1600 (trough effect) on day 0 (baseline) and at 1 and 3 months. At each stage and time point, the mean IOP reductions from baseline were evaluated for both groups, and success rates (minimum 15% reduction) were determined. RESULTS: At baseline, the mean peak/trough IOPs with TDC were 20.2/21.6 and 19.9/21.4 mmHg in latanoprost and brimonidine groups, respectively. Latanoprost+TDC reduced the mean peak/trough IOP by 4.4/3.4 and 5.2/3.5 mmHg at 1 and 3 months. The corresponding values for brimonidine+TDC were 3.9/2.9 and 4.6/2.9 mmHg. Each of these results represented a significant reduction from baseline (P<0.001 for all); however, the groups' peak/trough reductions from baseline did not differ at any time point (P>0.05 for all). With the latanoprost+TDC combination, the peak/trough success rates at 1 and 3 months were 76.3%/42.1% and 77.1%/40%. The corresponding values with the brimonidine+TDC combination were 71.8%/41% and 77.7%/41.7%. There were no significant differences in the groups' success rates at any time point (P>0.05 for all). CONCLUSION: Addition of latanoprost 0.005% or brimonidine 0.2% to TDC reduces peak/trough IOPs significantly and the effects of these combinations are comparable.

Adult↗
PubMed2000

Complications of extracapsular cataract surgery in chronic renal failure patients.

PURPOSE: In chronic renal failure (CRF) patients the risk of per- and post-operative complications in cataract surgery is high. The most frequent complications observed in these patients and the prevalence of cataract were studied. METHODS: Eighty-two CRF patients who had undergone ophthalmic examination between December 1996 and April 1998 at Başkent University, Department of Ophthalmology, were retrospectively analysed. Of 82 patients, 18 eyes of 14 CRF patients between 37 and 79 years of age underwent cataract extraction. Planned extracapsular cataract extraction was performed in all patients and all but one had posterior chamber intraocular lens implantation. In the post-operative period, scrapings of the corneal infiltrates were cultured and smears were examined, and the conjunctiva was swabbed and cultured also. RESULTS: Per-operative hypotony and scleral collapse occurred in 1 patient, and another had haemorrhage in the anterior chamber. Post-operatively, suture infiltration was observed in 10 eyes. These lesions disappeared after topical steroid and antibiotic treatment. CONCLUSIONS: Patients with CRF require special surgical considerations since they face both general surgical problems and others that arise due to their disease.

Aged↗
PubMed2000

Anterior segment indocyanine green angiography in scleral inflammation.

PURPOSE: To assess the feasibility of using indocyanine green angiography in scleral inflammation; to define the characteristic patterns of the anterior segment vasculature for this anterior segment disease; and to correlate the findings with those of anterior segment fluorescein angiography. METHODS: Anterior segment fluorescein and indocyanine green digital angiography were used to evaluate scleral inflammation in 3 patients with diffuse episcleritis, 2 patients with nodular episcleritis and 5 patients with nodular scleritis. Angiograms from both techniques were assessed based on the time for complete disappearance of the dye and the type of leakage. RESULTS: Both fluorescein and indocyanine green dye appeared in vessels at approximately the same time, but, whereas fluorescein had disappeared completely from vessels by the 70th second, indocyanine green was observed within vessels for up to 23 min. Leakage of fluorescein occurred in all patients with diffuse episcleritis but staining occurred in only 1 patient with nodular scleritis. No leakage of indocyanine green, or staining, occurred in patients with diffuse episcleritis. However, leakage of indocyanine green was apparent in all nodular episcleritis and scleritis patients, staining the nodules in patchy form. CONCLUSION: The longer transit time, as well as leakage and staining patterns due to its protein-binding properties, make indocyanine green angiography a potentially useful technique in the investigation of patients with scleral inflammation, and in distinguishing diffuse from nodular variants. Further studies are necessary to correlate staining patterns with clinical findings.

Adult↗
PubMed2000

Optic disk neovascularization in a patient with cytomegalovirus retinitis associated with renal transplantation.

PURPOSE: To report the development of optic nerve head neovascularization during the recovery phase of cytomegalovirus (CMV) retinitis in a renal allograft recipient. CASE REPORT: A 46-year-old male renal allograft recipient developed CMV retinitis seven months after transplantation. At the time of the diagnosis, the patient was being immunosuppressed with prednisone, cyclosporine, and azathioprine, and was treated with repeated intravitreal and intravenous ganciclovir. Six weeks after the initiation of therapy, optic disk neovascularization developed. This was confirmed by fluorescein angiography, which showed no areas of retinal capillary nonperfusion. At this stage, active retinal lesions were partially resolved. Apart from intraocular inflammation, no other cause of neovascularization was detected. Over the following six months, optic disk neovascularization regressed spontaneously without causing vitreous hemorrhage or visual loss. There was no recurrence of CMV retinitis during follow-up. CONCLUSION: Optic disk neovascularization may develop in the healing phase of CMV retinitis in renal transplant recipients.

Cytomegalovirus Infections↗
PubMed2000

Clinical features and keratoplasty results in keratoconus complicated by acute hydrops.

PURPOSE: Acute hydrops develops when Descemet's membrane and the endothelium of the ectatic cornea separates to allow aqueous humor to enter the stroma. The current study was done to determine if penetrating keratoplasty (PK) in keratoconus patients with resolved hydrops has a poor prognosis. METHODS: A retrospective chart review of 35 eyes of 35 patients with keratoconus who underwent PK after the resolution of acute hydrops (Group 1) and of 74 eyes of 69 patients who had PK without a previous history of acute hydrops (Group 2) was performed. The chi-square test was used for statistical analysis. RESULTS: The mean age in Group 1 was 21.1+/-11. 0 years. The mean age in Group 2 was 23.2+/-14.4 years. Vernal keratoconjunctivitis was present in 11 patients in Group 1 (31%) and in 12 (17.4%) patients in Group 2. Loose sutures were present in two patients (6%) in Group 1; both resulted in loose suture-related corneal neovascularization. Loose sutures developed in five patients (7%) in Group 2. In Group 1, three patients (9%) had microbial keratitis. Microbial keratitis was seen in five patients (7%) in Group 2. Two patients (6%) in Group 1 developed late endothelial graft failure. In Group 2, one eye (1%) developed early and one eye (1%) late epithelial graft rejection; five eyes (7%) developed late endothelial graft rejection. There was no statistically significant difference between the two groups with respect to the incidence of graft rejection. At the last examination, 34 eyes in Group 1 had clear grafts; in the second group, graft clarity was achieved in 71 eyes. CONCLUSION: Penetrating keratoplasty in hydrops is successful in terms of graft clarity and visual outcome in patients with keratoconus after the resolution of hydrops. The patients should have preoperative and postoperative anti-allergic treatment and close follow-up for possible complications.

Acute Disease↗
PubMed2000

Granulomatous anterior uveitis in a patient with CREST syndrome.

The CREST syndrome is a variant form of progressive systemic sclerosis. Apart from the occurrence of keratoconjunctivitis sicca, other types of ocular involvement associated with this variant are quite rare. We present the case of a 73-year-old woman with the CREST variant of progressive systemic sclerosis who developed unilateral granulomatous anterior uveitis. Systemic and laboratory testing failed to suggest evidence for any other associated systemic disease as a possible cause of the granulomatous uveitis. The inflammation was successfully controlled with topical steroids and mydriatics. While a small number of cases of uveitis have been reported in other variant forms of progressive systemic sclerosis, to date there have been no descriptions of uveitis associated with the CREST syndrome.

Administration, Topical↗
PubMed1999

Efficacy of low-dose and long-term oral acyclovir therapy after penetrating keratoplasty for herpes simplex heratitis.

PURPOSE: To evaluate the efficacy of long-term and low-dose prophylactic oral acyclovir therapy in preventing the recurrence of herpetic infection and increasing graft survival in patients who undergo penetrating keratoplasty (PK) for herpes simplex keratitis (HSK). PATIENTS AND METHODS: Nineteen patients were included in the study, who underwent PK for herpes keratitis from July 1993 to November 1995, received oral acyclovir, and were followed at least 12 months. Group 1 included 12 patients with corneal scarring without perforation. These patients were free of inflammation for a mean of 4.1+/-2.2 months preoperatively, and received oral acyclovir 400 mg/day postoperatively for one year. Seven patients (Group 2) who developed corneal perforation due to necrotizing keratitis were treated with tissue adhesives, therapeutic contact lenses, and topical antiviral and oral acyclovir therapy for the resolution of active inflammation followed by PK after a mean of 3.8+/-2.1 months follow-up. They received oral acyclovir 400 mg/day postoperatively for one year in addition to standard postoperative therapy. The control group consisted of 16 patients (Groups 3 and 4) who underwent PK for herpes simplex keratitis and did not receive oral acyclovir. The indication for PK was corneal opacity and impaired visual acuity in 12 patients (Group 3) and corneal perforation in four (Group 4). RESULTS: After an average of 25 months follow-up, there was only one recurrence (8.3%) in Group 1 and two cases (28.6%) of herpetic recurrence in Group 2. Recurrence occurred at two months in one patient while he was taking oral acyclovir. Two of these recurrences followed the withdrawal of oral acyclovir therapy after one year of therapy. In contrast, in control groups there were four cases of herpetic recurrence (33.3%) in Group 3 and two (50%) in Group 4 after a mean of 30.5 months postoperative follow-up. In the study groups, a rejection episode was seen in three patients (15.8%) which was successfully treated with medical therapy. One patient from Group 2 developed bacterial keratitis which subsequently resulted in graft failure. All grafts remained clear in the other patients (94.7%). In the control groups, rejection developed in seven patients. Three rejection episodes were treated successfully. The other four developed graft failure in spite of intensive medical therapy. CONCLUSIONS: Our results suggest that postoperative oral acyclovir therapy is effective in preventing the recurrence of herpetic infection. However, the recurrence may develop after cessation of oral acyclovir therapy, especially in patients who underwent PK for corneal perforation due necrotizing HSK.

Acyclovir↗
PubMed1999

Late bleb-related endophthalmitis after trabeculectomy with mitomycin C.

To present two cases of delayed-onset postoperative endophthalmitis following trabeculectomy combined with mitomycin C for secondary glaucoma after penetrating keratoplasty. We retrospectively evaluated two patients with late endophthalmitis after trabeculectomy combined with intraoperative mitomycin C application. Both patients underwent trabeculectomy for uncontrolled glaucoma following penetrating keratoplasty and they developed thin-walled cystic blebs. Intraocular pressure was normal, and grafts remained clear postoperatively. Severe endophthalmitis with hypopyon developed at 3 and 7 months postoperatively. Both patients had concomitant bleb infection. They underwent vitreous sampling and intravitreal injection of vancomycin and amikacin and were given topical fortified and systemic antibiotic therapy. Intravitreal injection was repeated once in both patients. Cultures grew Streptococcus pneumonias in one and Staphylococcus aureus in the other. Although the treatment of endophthalmitis was successful in both patients, only one of them achieved useful vision (20/40). For the other patient who had been infected with S. pneumoniae, vision was light perception. Delayed-onset endophthalmitis following trabeculectomy with mitomycin C application is a severe and vision threatening complication. It seems that the development of thin cystic filtering blebs secondary to intraoperative mitomycin C application may be a predisposing factor for bleb-related late endophthalmitis.

Adult↗
PubMed1999

Microbial keratitis following penetrating keratoplasty.

PURPOSE: To investigate the prevalence of microbial keratitis, predisposing risk factors and treatment modalities in patients who developed keratitis following penetrating keratoplasty (PK). PATIENTS AND METHODS: The records of 285 patients who had undergone PK between January 1991 and December 1995 in a tertiary care center were reviewed. Patients who developed postoperative microbial keratitis were evaluated for predisposing risk factors, microbiological etiology, response to broad spectrum antibiotic therapy and subsequent PK. Patients were mainly treated with fortified topical antibiotics with or without repeat PK. RESULTS: Of the 285 patient records reviewed, microbial keratitis developed in 21 eyes of 21 patients (7.4%). Seventy-one percent of infections occurred within 6 months after grafting. Keratitis initially began from the donor-recipient border in 16 cases (76.2%) and were central or paracentral in 5 patients. Predisposing risk factors included loose or exposed suture (9), suture removal (1), persistent epithelial defect (3), graft failure (3), contact lens wear (1), Stevens-Johnson syndrome (1). Fifteen (71.4%) patients were culture-positive consisting of Streptococcus pneumoniae (7), Staphylococcus aureus (5), Pseudomonas aureginosa (2), and Hemophilus influenzae (1). Forty-three percent of patients were successfully treated with medical therapy only. Seven patients underwent second PK for visual rehabilitation and 4 for tectonic purposes. After medical and surgical therapy, graft clarity was achieved in 17 (81%) of patients. CONCLUSIONS: The microbial keratitis following PK is a major postoperative problem affecting the long term prognosis. Careful selection of patients, and preoperative and postoperative control of risk factors, may decrease the frequency of this complication. Several factors, including loose or exposed sutures, epithelial defects, ocular surface disorders, and graft failure, may predispose patients to develop microbial keratitis following PK.

Adolescent↗