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Dive into the research topics where Handan Canan is active.

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Featured researches published by Handan Canan.


British Journal of Ophthalmology | 2013

The effect of smoking on choroidal thickness measured by optical coherence tomography

Selcuk Sizmaz; Cem Küçükerdönmez; Eylem Yaman Pinarci; Aylin Karalezli; Handan Canan; Gürsel Yilmaz

Background/aims To investigate the effect of smoking on choroidal thickness using Fourier domain optical coherence tomography. Methods 17 otherwise healthy smokers (study group) and 17 non-smokers (control group) were enrolled. In the study group, all participants underwent optical coherence tomography scanning at baseline, and 1 and 3 h following smoking one standard cigarette. Also the participants of the control group underwent optical coherence tomography scanning in the morning which was followed by two further examinations at the first and third hours, respectively. Choroidal thickness measurements were performed. Results The mean choroidal thickness at the fovea prior to smoking was 301.1±63.1 μm, which decreased to 284.2±56.7 μm at 1 h and 270.8±80.0 μm at 3 h following smoking (p=0.001). The mean choroidal thickness was significantly decreased following smoking at all five extrafoveal points. The difference in choroidal thickness was not statistically significant at 1 and 3 h of smoking at all six points. In the control group, the mean baseline choroidal thickness at the fovea was 270.6±57.9 μm, which was 272.5±52.4 μm at 1 h and 273.8±57.4 μm at 3 h (p=0.816). Conclusions Cigarette smoking causes a significant decrease in choroidal thickness following smoking. Fourier domain optical coherence tomography can effectively demonstrate choroidal thickness.


Current Eye Research | 2013

Optical Coherence Tomography for Measuring the Tear Film Meniscus: Correlation with Schirmer Test and Tear-Film Breakup Time

Rana Altan-Yaycioglu; Selcuk Sizmaz; Handan Canan; Muge Coban-Karatas

Abstract Purpose: To compare tear meniscus height (TMH) and area (TMA) values obtained by optical coherence tomography (OCT) with the Schirmer test and tear-film break-up time (TBUT) values. Materials and methods: In this prospective cross-sectional study, the right eyes of 300 consecutive patients were studied. All patients underwent routine ophthalmologic examination. Schirmer and TBUT measurements were taken, and tear-film OCT images were obtained. Using OCT, the TMH (i.e. the line connecting the intersection of the meniscus with the cornea and eyelid) and cross-sectional TMA were calculated. Patients were divided into Groups 1 (Schirmer values ≤5 mm) and 2 (Schirmer values >5 mm). Data were analyzed using SPSS 13.0 software. The Mann–Whitney U-test was used for the comparison of groups. Correlations between tear parameters were analyzed. Results: There were no significant differences in age, logMAR, or IOP values (p = 0.480, 0.077 and 0.146, respectively) between the two groups. Mean TBUTs were 5.1 ± 2.9 and 9.5 ± 4.2 s for Groups 1 and 2, respectively (p < 0.001). Mean TMHs were 237.9 ± 108.9 and 324.3 ± 158.9 μm for Groups 1 and 2, respectively (p < 0.001). Mean TMAs were significantly lower in Group 1 compared to Group 2 (p < 0.001; 0.027 ± 0.028 versus 0.055 ± 0.059 mm2, respectively). Correlations between Schirmer values and TMH, and between Schirmer values and TMA, were significant (p = 0.001 and <0.001, respectively). Conclusions: OCT values were significantly lower in patients with Schirmer values of <5 mm. Tear meniscus measurements obtained by OCT are reliable for establishing a diagnosis of dry eye.


Orbit | 2010

Nasolacrimal Duct Obstruction: Clinicopathologic Analysis of 205 Cases

Rana Altan-Yaycioglu; Handan Canan; Selcuk Sizmaz; Nebil Bal; Aysel Pelit; Yonca A. Akova

Purpose: To investigate the histopathological results of lacrimal sac biopsies in patients with primary acquired nasolacrimal duct obstruction. Methods: In this prospective non-comparative study, 205 consecutive patients, who were diagnosed as primary acquired nasolacrimal duct obstruction, were included. Patients with history of trauma and/ or surgery in the periorbital area, punctum or canalicular obstruction were excluded from the study. Patients were evaluated for age, gender, history, and presenting symptoms. Lacrimal drainage system abnormalities were assessed. Lacrimal system irrigation, dacryocystography, and in selected cases dacryoscintigraphy was performed. All patients underwent external dacryocystorhinostomy. Biopsy specimens were obtained from the posterior inferior flap and examined by the same pathologist. Results: Forty-seven male and 158 females with age ranging from 6 to 81 years (mean 47.5 ± 16.2 years) were included in the study. Only one patient had the diagnosis of chronic leukemia, others had no preexisting history of systemic disease. Pathologic examination revealed chronic inflammation (n= 178), fibrosis without inflammation (n= 19), normal mucosa (n= 4), and lymphoid hyperplasia (n= 1). Three patients had abnormal pathology: Lymphoproliferative disease in the patient with chronic leukemia, granulomatous inflammation, and basosquamous cell carcinoma. Conclusion: In primary nasolacrimal duct obstruction, pathological examination of the lacrimal sac revealed chronic inflammatory changes in most patients. Even though rare, malignant or systemic disease in patients with neither specific history nor clinical or radiological finding might be observed in these cases. Thus, we recommend taking biopsy if any suspicion of abnormality of the lacrimal sac exists.


European Journal of Ophthalmology | 2014

Retinal and choroidal thickness changes after single anti-VEGF injection in neovascular age-related macular degeneration: ranibizumab vs bevacizumab

Selcuk Sizmaz; Cem Kucukerdonmez; Ali Kal; Eylem Yaman Pinarci; Handan Canan; Gürsel Yilmaz

Purpose To evaluate and compare the effects of single intravitreal injection of ranibizumab and bevacizumab on central retinal and choroidal thickness in patients with neovascular age-related macular degeneration (AMD). Methods Forty eyes of 40 patients with neovascular AMD that underwent intravitreal injection of vascular endothelial growth factor inhibitors (anti-VEGFs) were included. Patients were randomized into 2 groups: 20 eyes received ranibizumab and 20 eyes received bevacizumab injection. Central retinal and choroidal thicknesses of all eyes at baseline and 1 month postinjection scans were measured with Fourier-domain optical coherence tomography (OCT). Student t test and Mann-Whitney U test were used to compare the data. Results The mean central retinal thickness (CRT) showed significant decrease after single injection of ranibizumab (from 345.0 μm to 253.5 μm, p<0.01) and bevacizumab (from 329.5 μm to 251.0 μm, p<0.01) at the first month, respectively. There was no significant difference regarding the CRT change between groups (p = 0.39). The mean choroidal thickness decreased from 158.6 μm (115-317) to 155.5 μm (111-322) in the ranibizumab group and from 211.5 μm (143-284) to 201.5 μm (93-338) in bevacizumab group. The decrease was not significant between groups (p = 0.35). Conclusions Intravitreal injection of both ranibizumab and bevacizumab provided a significant decrease in CRT; however, the agents caused no significant change in choroidal thickness. Additionally, no difference between ranibizumab versus bevacizumab was observed related to macular edema inhibition.


Journal of Aapos | 2010

Comparison of UK and US screening criteria for detection of retinopathy of prematurity in a developing nation

Hande Gulcan; Handan Canan; Handan Ankarali; Birgin Torer; Yonca A. Akova

PURPOSE To determine the incidence, risk factors, and appropriateness of differing guidelines in developed nations for screening for retinopathy of prematurity (ROP) in a single nursery in a large urban city in southern Turkey. METHODS The records of 260 premature infants born ≤34 weeks in a single tertiary unit were retrospectively reviewed for ROP risk factors and diagnosis. Applicability of UK and US criteria were assessed by the use of receiver operating characteristic curves. RESULTS ROP of any stage was present in 60 infants (23%); ROP requiring treatment was seen in 30 (11.5%). Univariate analysis showed a significant relationship among the following factors: gestational age, birth weight, total duration of supplemental oxygen, duration of mechanical ventilation, respiratory distress syndrome, anemia, and intraventricular hemorrhage (p < 0.0001). Multiple logistic regression analysis showed gestational age (p = 0.039), birth weight (p = 0.05), respiratory distress syndrome (p = 0.05), and anemia (p = 0.004) as independent predictors of ROP requiring treatment. Area under curve for gestational age alone for diagnosing stage 2 or greater ROP was 0.824 ± 0.03 (p = 0.0001) and for birth weight alone was 0.808 ± 0.03 (p = 0.0001). UK screening criteria detected all stage 2 and greater ROP; US screening criteria missed 2 infants with stage 2 ROP but detected all treatment-requiring disease. Adoption of these screening criteria would have reduced unnecessary examinations by either 21% (UK) or 37% (US). CONCLUSIONS UK and US criteria improved the detection accuracy for ROP requiring treatment in Turkey and should be studied for other developing nations.


Journal of Cataract and Refractive Surgery | 2012

Late capsular block syndrome presenting with posterior capsule opacification

Eylem Yaman Pinarci; Sezin Akça Bayar; Selcuk Sizmaz; Handan Canan; Gürsel Yilmaz

PURPOSE: To assess the results of posterior neodymium:YAG (Nd:YAG) laser capsulotomy in patients with late postoperative capsular block syndrome (CBS) with decreased vision because of posterior capsule opacification (PCO). SETTING: Baskent University Hospital, Department of Ophthalmology, Ankara, Turkey. DESIGN: Case‐control study. METHODS: Patients with CBS who had phacoemulsification and foldable hydrophilic or hydrophobic acrylic intraocular lens implantation with continuous curvilinear capsulorhexis were retrospectively reviewed. Transparent to slight milky fluid had collected in the capsular bag. Capsular block syndrome was undiagnosed before the PCO developed. The CBS was treated with Nd:YAG laser capsulotomy, after which the change in refraction, corrected distance visual acuity (CDVA), intraocular pressure (IOP), complications, and inflammation rate were evaluated. Follow‐up examinations were at 1 day, 1 week, and 1 and 6 months. RESULTS: The mean time between cataract surgery and laser capsulotomy was 48 months ± 10.27 (SD) (range 28 to 66 months). The Nd:YAG capsulotomy was successful in all eyes. Capsulotomy did not change the refraction in 14 eyes (93.3%). One patient (6.6%) had a change of +0.75 diopter. After capsulotomy, the logMAR CDVA improved in 13 cases (mean 0.26 ± 0.18; range 0.0 to 0.7) and did not change in 2 cases. There were no complications, inflammation, or significant IOP changes. CONCLUSIONS: Neodymium:YAG laser capsulotomy in patients with PCO associated with late CBS increased visual acuity without a significant change in refraction or IOP. Capsular block syndrome may be asymptomatic and remain undiagnosed for a long time after cataract surgery before PCO develops. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned.


Current Eye Research | 2014

Interexaminer Reproducibility of Optical Coherence Tomography for Measuring the Tear Film Meniscus

Handan Canan; Rana Altan-Yaycioglu; Burak Ulas; Selcuk Sizmaz; Muge Coban-Karatas

Abstract Purpose: New optical coherence tomography (OCT) devices with anterior segment module are able to measure the tear meniscus height (TMH) and tear meniscus area (TMA). Since the borders of the area and the height are to be marked by an examiner, the measurements are prone to be subjective. Herein, we aimed to evaluate the interexaminer reproducibility of the tear meniscus measurements with OCT. Materials and Methods: In this prospective cross-sectional study, both eyes of 300 consecutive patients with and without dry eye were studied. Following routine ophthalmologic examination, tear-film OCT images were obtained. Two examiners, who were unaware of the other examiner’s results, measured the TMH (i.e. the line connecting the intersection of the meniscus with the cornea/sclera and eyelid) and cross-sectional TMA. The reliability and correlation of the two examiners’ results were assessed. Results: Four right and six left eyes were excluded from the final analysis, so a total of 590 eyes were evaluated. The mean difference of the two examiners’ measurements of both eyes was −0.001 ± 0.027 mm2 in TMA, and −21.29 ± 39.95 μm in TMH. An agreement between the two examiners was found regarding TMA and TMH measurements for right and left, as well as both eyes (Cronbach’s alpha > 0.900, for all). Also, the correlation between both variables was high (inter item correlation matrix > 0.840, for all). Conclusions: We showed a strong statistical agreement for both TMA and TMH measurements. According to our results, we believe that FD-OCT device is dependable in measuring the TMA and TMH values, given that its results are reproducible.


Clinical Ophthalmology | 2013

Surgical results of combined pars plana vitrectomy and phacoemulsification for vitreous hemorrhage in PDR.

Handan Canan; Selcuk Sizmaz; Rana Altan-Yaycioglu

Background The purpose of this study was to evaluate the effectiveness, safety, and incidence of complications after combined clear corneal phacoemulsification with intraocular lens implantation and pars plana vitrectomy in eyes with proliferative diabetic retinopathy coexistent with significant cataract. Methods Eighty-five eyes of 85 patients with proliferative diabetic retinopathy underwent primary standard three-port vitrectomy with 20-gauge instruments and phacoemulsification with intraocular lens implantation for vitreous hemorrhage from 2008 to 2011. The main outcome measures were visual outcomes and surgical complications. Results Forty patients were male and 45 were female. Their age ranged from 40 to 77 years with a mean of 59.6 years. The mean follow-up was 13 months, with a range of 6–48 months. The preoperative logMAR visual acuity changed from 2.62 ± 0.6 to 0.8 ± 0.7 postoperatively. Postoperatively, visual acuity improved in 79 eyes (92.9%), and did not change in six eyes (7.1%). Intraoperative complications were transient corneal edema (five eyes) and posterior capsular rupture (one eye). Postoperative complications consisted of transient intraocular pressure elevation (25 eyes), corneal epithelial defects (six eyes), anterior chamber reaction (four eyes), hyphema (two eyes), posterior synechiae (four eyes), vitreous hemorrhage (23 eyes), retinal tears (five eyes), retinal detachment (one eye), and neovascular glaucoma (one eye). Conclusion Our study suggests that the combined operation of pars plana vitrectomy, phacoemulsification, and intraocular lens implantation is safe and effective for patients with proliferative diabetic retinopathy. We believe that the visual outcome and complications depended primarily on underlying posterior segment pathology and were not related to the combined procedure technique.


Clinical Interventions in Aging | 2014

Visual outcome of intravitreal ranibizumab for exudative age-related macular degeneration: timing and prognosis.

Handan Canan; Selcuk Sizmaz; Rana Altan-Yaycioglu; Çağla Sarıtürk; Gürsel Yilmaz

Purpose To describe 1-year clinical results of intravitreal ranibizumab treatment in patients with choroidal neovascularization secondary to exudative age-related macular degeneration (AMD) and to evaluate whether early treatment is a predictive value for prognosis of the disease. Materials and methods Clinical records were retrospectively reviewed of 104 eyes that underwent intravitreal ranibizumab therapy for exudative AMD. Patients were divided into two groups according to their symptom duration: group 1, <1 month; and group 2, 1–3 months. After three monthly injections, patients were examined monthly, and subsequent injections were performed as needed. Results There were 43 female (48.9%) and 45 males (51.1%). The follow-up time was 13.7±1.9 (12–19) months. The mean logarithm of minimum angle of resolution best-corrected visual acuity (BCVA) improved significantly, from 0.45±0.639 at baseline to 0.08±0.267 at 12 months in group 1, and from 1.06±0.687 at baseline to 0.75±0.563 at 12 months in group 2. The increase in BCVA was statistically significant in group 1 (P=0.009). The mean central retinal thickness (CRT) decreased significantly, from 355.13±119.93 μm at baseline to 250.85±45.48 μm at 12 months in group 1, and from 371.88±91.047 μm at baseline to 268.61±53.51 μm at 12 months in group 2. The decrease in CRT was statistically significant in group 1 (P=0.001). Conclusion Intravitreal ranibizumab therapy was effective in significantly increasing mean BVCA and reducing CRT. Shorter duration of AMD, as measured by the subjective duration of visual symptoms, is associated with better visual outcome after treatment.


Journal of Cataract and Refractive Surgery | 2009

Intraocular pressure after phacoemulsification in eyes with pseudoexfoliation

Rana Altan-Yaycioglu; Handan Canan; Aysel Pelit; Yonca A. Akova

eventful phacoemulsification resulted in a small but positive effect on IOP. Their retrospective analysis of 1122 eyes with PXF showed that the preoperative IOP level had a significant effect on the postoperative IOP reduction. Although the patient number is smaller and the follow-up shorter, we would like to add the results of our study of postoperative IOP in PXF cases, part of which has been presented (R. Altan-Yaycioglu, MD, et al., ‘‘The Results of Phacoemulsification in Pseudoexfoliative Cataracts: A Comparative Study,’’ presented at the ASCRS Symposium on Cataract, IOL and Refractive Surgery, Chicago, Illinois, USA, April 2008).

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