Central serous chorioretinopathy following oral quetiapine.

Central serous chorioretinopathy (CSCR) is a chorioretinal disease that is characterized by central vision loss and is usually seen in middle-aged males. It has been associated with the use of various drugs, including corticosteroids and phosphodiesterase inhibitors. We present the case of a 36-year-old male who developed CSCR after a few weeks of irregular use of quetiapine for his sleep problems. The clinical findings of the patient improved shortly after he stopped using the drug, and at the end of the two-month period complete recovery was observed. Quetiapine is an atypical antipsychotic that exerts its effects on dopamine and serotonin receptors. There are studies showing that these neurotransmitters may play a role in the control of choroidal vascular permeability, which is the underlying cause of CSCR. Therefore, we believe that quetiapine may have a causal relationship with CSCR. To our knowledge, this is the first case report documenting full recovery from quetiapine associated CSCR.

The Use of Autologous Serum Eye Drops after Epithelium-off Corneal Collagen Crosslinking.

SIGNIFICANCE: After epithelium-off crosslinking (CXL), epithelial closure time and post-operative pain are an important issue in terms of possible complications and patient comfort. We report a prospective randomized study about the use of autologous serum eye drops after CXL. PURPOSE: This study aims to evaluate the effect of autologous serum eye drops on epithelial healing and post-operative pain after CXL. METHODS: Sixty patients diagnosed as having progressive keratoconus and treated with accelerated CXL (9 mW/cm for 10 minutes) randomly received 20% autologous serum eye drops (autologous serum group, n = 30) or artificial tears (control group, n = 30). Patients were evaluated every day after the surgery, and the day of epithelial closure was recorded. All patients were asked to report the maximum pain level using the Wong-Baker FACES Pain Rating Scale at the end of each day until the epithelial closure was completed. The change in topographic parameters and haze were recorded at 6 months. RESULTS: The mean epithelial closure time was significantly lower in the autologous serum group than in the control group (2.37 ± 0.49 and 2.67 ± 0.47 days, respectively; P = .02). There was a statistically significant difference between the pain scores in the first and second days of surgery between the two groups (first-day autologous serum autologous serum group: 2.80 ± 0.66 and control group: 3.50 ± 0.82, P = .01; second-day autologous serum group: 1.73 ± 0.69 and control group: 2.20 ± 0.76, P = .02). Pre-operative and post-operative topographic parameters and haze at 6 months were similar between the two groups (P > .05 for all). CONCLUSIONS: Use of autologous serum eye drops after CXL accelerates epithelial healing and reduces post-operative pain. Shortening the duration of epithelial closure would be beneficial in reducing possible complications and increasing patient comfort.

Biomechanics in DALK: Big bubble vs manual lamellar dissection / Biomecânica no DALK: grande bolha versus dissecção manual lamelar

ABSTRACT Purpose: The present study's aim was to compare the biomechanical properties of corneal tissue in patients who underwent deep anterior lamellar keratoplasty (DALK) surgery, with successful big bubble formation and manual lamellar dissection, during failed big bubble formation. Methods: This retrospective comparative study included 60 eyes from 60 keratoconus patients who previously underwent DALK surgery. These patients were categorized as big bubble (+) or big bubble (−) based on the success or failure of big bubble formation during the surgery. The big bubble (+) group included 42 eyes, while the big bubble (−) group had 18 eyes. Moreover, the patients were regrouped as 0.25 mm and 0.50 mm to evaluate the effects of the disparity between donor and trephine punches on the biomechanical properties of the cornea. These biomechanical properties, characterized by corneal hysteresis and the corneal resistance factor, were measured using the Ocular Response Analyzer 12 months after the surgery. Results: There was no statistically significant difference between the big bubble (+) and big bubble (−) groups in the biomechanical properties of the cornea (corneal hysteresis: 10.06, 10.25; p=0.716/corneal resistance factor: 10.15, 10.07; p=0.805, respectively). In addition, pachymetry results were not statistically different between the two groups. Multivariate regression analysis revealed that corneal hysteresis and corneal resistance factor were positively associated with central corneal thickness (p<0.001/r2=0.506; p<0.001/r2=0.561, respectively). However, the study did not demonstrate a relationship between any of the punch sizes and corneal hysteresis or between the punch sizes (p=0.673) and the corneal resistance factor (p=0.643). Conclusions: The corneal hysteresis and corneal resistance factor values were similar in big bubble and manual lamellar dissection after DALK. Thus, manual lamellar dissection was not a disadvantage considering the cornea's biomechanical properties.

RESUMO Objetivo: O objetivo do estudo foi comparar pa râmetros biomecânicos corneanos de pacientes com cirurgia de ceratoplastia lamelar anterior profunda com formação bem-sucedida de bolha e dissecção lamelar manual, frente à falha de formação da grande bolha. Métodos: Este estudo comparativo retrospectivo incluiu 60 olhos de 60 pacientes com ceratocone submetidos à cirurgia de ceratoplastia lamelar anterior profunda. Os pacientes foram agrupados como grande bolha (+) e grande bolha (-) de acordo com o sucesso da formação da grande bolha durante a cirurgia. O grupo grande bolha (+) incluiu 42 olhos, enquanto o grupo grande bolha (-) tinha 18 olhos. Além disso, para a avaliação dos efeitos da disparidade entre alterações individuais nas propriedades biomecânicas da córnea, reagrupamos os pacientes em 0,25 mm e 0,50 mm. Parâmetros biomecânicos da córnea, caracterizados por histerese corneana e fator de resistência corneana foram medidos com o ORA 12 meses após a cirurgia. Resultados: Não houve diferença estatisticamente significativa entre os grupos grande bolha (+) e grande bolha (-) em relação aos parâmetros biomecânicos da córnea (histerese corneana: 10,06, 10,25, p=0,716/fator de resistência da córnea: 10,15, 10,07, p=0,805, respectivamente). Além disso, os resultados de paquimetria não diferiram estatisticamente entre os dois grupos. A análise de regressão multivariada demonstrou que a histerese da córnea e o fator de resistência corneana estavam associados positivamente com a espessura corneana central (p<0,001/r2=0,506, p<0,001/r2=0,561 respectivamente). No entanto, o estudo não revelou associação entre qualquer um dos tamanhos de punção e histerese corneana, bem como entre os tamanhos de punção e o fator de resistência corneano (p=0,673, p=0,643). Conclusões: A histerese da córnea e os valores do fator de resistência da córnea foram comparáveis com formação de grande bolha e dissecção manual lamelar na ceratoplastia lamelar anterior profunda. Assim, a dissecção manual lamelar não foi uma desvantagem, considerando os fatores biomecânicos da córnea.

Biomechanics in DALK: Big bubble vs manual lamellar dissection.

PURPOSE: The present study's aim was to compare the biomechanical properties of corneal tissue in patients who underwent deep anterior lamellar keratoplasty (DALK) surgery, with successful big bubble formation and manual lamellar dissection, during failed big bubble formation. METHODS: This retrospective comparative study included 60 eyes from 60 keratoconus patients who previously underwent DALK surgery. These patients were categorized as big bubble (+) or big bubble (-) based on the success or failure of big bubble formation during the surgery. The big bubble (+) group included 42 eyes, while the big bubble (-) group had 18 eyes. Moreover, the patients were regrouped as 0.25 mm and 0.50 mm to evaluate the effects of the disparity between donor and trephine punches on the biomechanical properties of the cornea. These biomechanical properties, characterized by corneal hysteresis and the corneal resistance factor, were measured using the Ocular Response Analyzer 12 months after the surgery. RESULTS: There was no statistically significant difference between the big bubble (+) and big bubble (-) groups in the biomechanical properties of the cornea (corneal hysteresis: 10.06, 10.25; p=0.716/corneal resistance factor: 10.15, 10.07; p=0.805, respectively). In addition, pachymetry results were not statistically different between the two groups. Multivariate regression analysis revealed that corneal hysteresis and corneal resistance factor were positively associated with central corneal thickness (p<0.001/r2=0.506; p<0.001/r2=0.561, respectively). However, the study did not demonstrate a relationship between any of the punch sizes and corneal hysteresis or between the punch sizes (p=0.673) and the corneal resistance factor (p=0.643). CONCLUSIONS: The corneal hysteresis and corneal resistance factor values were similar in big bubble and manual lamellar dissection after DALK. Thus, manual lamellar dissection was not a disadvantage considering the cornea's biomechanical properties.

Results of ethanol-assisted epithelium-on corneal cross-linking with and without intrastromal corneal ring implantation.

PURPOSE: To evaluate the topographic, refractive, and pachymetric changes after ethanol-assisted transepithelial corneal cross-linking (CXL) to stabilize progression of keratoconus (KC). PATIENTS AND METHODS: This study retrospectively evaluated the long-term topographic, refractive, and pachymetric changes in patients diagnosed with KC who underwent corneal cross-linking and/or intrastromal corneal ring segment (ICRS) implantation. The subjects were divided into three groups, corresponding to eyes treated with CXL alone (group 1), CXL and ICRS at the same time (group 2), and CXL after ICRS implantation (group 3). Corrected visual acuity and refraction, steep keratometry (SteepK) values, steepest keratometry reading on sagittal curvature map, and corneal thickness were recorded preoperatively and at each visit. Changes between measurements were assessed during follow-up. RESULTS: Corrected distant visual acuity (CDVA) values improved in all groups compared with baseline, but the differences were not statistically significant except for the first year (p > 0.05). In groups 1 and 3, SteepK values did not change statistically significantly during the entire follow-up (p > 0.05). In group 2, SteepK values statistically significantly decreased at all follow-up examinations compared with baseline, determined as the first month after ICRS implantation (p < 0.05). Complication rates were acceptable without any need for surgical intervention. CONCLUSIONS: Single-session ethanol-assisted transepithelial CXL with or without ICRS implantation was a safe and effective procedure to halt progression of KC.

The role of patient's systemic characteristics and plateletcrit in developing toxic anterior segment syndrome after uneventful phaco surgery: A case-control study.

PURPOSE: To compare the systemic and ocular characteristics and laboratory findings of patients developing toxic anterior segment syndrome (TASS) after uneventful phaco surgery with unaffected subjects undergoing the same surgery in the same session. DESIGN: A retrospective case-control study. METHODS: The study group consisted of 26 eyes of 26 patients who underwent uneventful phaco surgery and who went on to develop TASS, while the control group included 39 subjects who had routine phaco surgery in the same session by the same surgeon. The sterilization stages of reusable instruments, disposable instruments, and compositions were recorded. The preoperative systemic diseases, complete blood count parameters, glycosylated hemoglobin (HbA1c), biochemical parameters, thyroid hormone profiles, and the surgical features were compared between the two groups. RESULTS: Type 2 diabetes mellitus (DM), systemic hypertension (HT), hyperlipidemia, chronic ischaemic heart disease, and chronic renal failure were significantly more common in the TASS group (p < 0.05). Proliferative diabetic retinopathy was also more frequent in the TASS group (p = 0.003). Mean HbA1c% values, white blood cell count, neutrophil/lymphocyte ratio, platelet counts, platelet distribution width, and plateletcrit parameters were significantly higher in the TASS group (p < 0.05). Multivariate logistic regression analysis revealed that a high plateletcrit level (p = 0.001, odds ratio [95% CI]; 22.27 [3.36-147.76]) and systemic HT (p = 0.044, odds ratio [95% CI]; 7.13 [1.05-48.12]) are independently associated with the development of TASS. CONCLUSION: Although TASS may arise as a result of insufficient sterilization of instruments or intraocular solutions, patient factors may also contribute to its development. Systemic vascular disorders such as uncontrolled type 2 DM, systemic hypertension, and hyperlipidemia may increase the risk of TASS after uneventful phaco surgery. Abnormal parameters associated with systemic inflammation, such as higher plateletcrit level, may facilitate the development of TASS. These findings may be a predicting factor of TASS development for uneventful cataract surgeries.

Peripapillary Choroidal Thickness and Retinal Nerve Fiber Layer in Untreated Patients with Obstructive Sleep Apnea-Hypopnea Syndrome: A Case-Control Study.

PURPOSE: To evaluate peripapillary choroidal thickness (PPCT), central macular choroidal thickness (CMCT), and retinal nerve fiber layer (RNFL) thickness in untreated patients with obstructive sleep apnea-hypopnea syndrome (OSAHS). METHODS: This prospective, randomized, and comparative study was conducted in a university ophthalmology clinic. 106 eyes of 106 patients with OSAHS and 44 eyes of 44 healthy individuals were evaluated in this study. Only right eyes were evaluated. The patients with OSAHS were divided into three groups as mild (group 1), moderate (group 2), and severe (group 3) according to apnea-hypopnea index. The PPCT, CMCT, and RNFL measurements were performed by using spectral domain optical coherence tomography with enhanced depth imaging technique. The main parameters assessed were PPCT-Temporal, PPCT-Superior, PPCT-Nasal, PPCT-Inferior quadrants, CMCT, and RNFL thicknesses. RESULTS: The PPCT of all quadrants was significantly thicker in the control group compared with the moderate and severe subgroups of OSAHS (p < 0.05). The PPCT-Superior and PPCT-Temporal were significantly thinner in the mild subgroup compared with the control group (p = 0.003 and p = 0.028, respectively). There was no difference between the control and mild groups regarding the RNFL thicknesses except nasal RNFL and inferotemporal RNFL which are thinner in the mild group. The RNFL thicknesses of all quadrants were significantly thicker in the control group compared with moderate and severe subgroups (p < 0.05). The CMCT was significantly thicker in the control group compared with all subgroups of OSAHS (p < 0.05). CONCLUSIONS: In OSAHS patients, PPCT, CMCT, and RNFL were significantly thinner compared with the control group. These results may explain why OSAHS patients are prone to normotensive glaucoma.

The Effect of Dexamethasone Intravitreal Implant on Retinal Nerve Fiber Layer in Patients Diagnosed with Branch Retinal Vein Occlusion.

PURPOSE: To evaluate the effect of a single dose of intravitreal dexamethasone (DEX) implant on retinal nerve fiber layer (RNFL) thickness in patients with branch retinal vein occlusion (BRVO) in a 6-month period. MATERIALS AND METHODS: This retrospective observational study included the patients with BRVO who received intravitreal DEX implant and whose assessment included the baseline RNFL thickness measurements. The data of 26 eyes of 24 patients were retrospectively analyzed. Spectral domain optic coherence tomography was used to measure peripapillary RNFL thickness in six regional subfields. Intraocular pressure (IOP) values at each visit were recorded. The data of single dose DEX implant during 6 months were assessed. RESULTS: The mean preoperative and postoperative 6th month nasal RNFL values were 85.4 ± 23.0 µm and 82.1 ± 17.6 µm, respectively, and the difference between the measurements was not statistically significant (p = 0.372). There was a slight decrease in the mean RNFL values postoperatively compared to the baseline values in all quadrants except supero-temporal quadrant; however, none of them reached statistically significant level (p > 0.05). The mean IOP values before and 6 months after implantation were 15.7 ± 2.9 mmHg and 16.5 ± 4.2 mmHg, respectively. The difference between the 6th month IOP values and baseline IOP values was not statistically significant (p = 0.236). CONCLUSION: Intravitreal DEX implant seems to have no adverse effect on RNFL thickness in BRVO patients in a 6-month period.

Vitamin B12 deficiency evaluation and treatment in severe dry eye disease with neuropathic ocular pain.

PURPOSE: This study aims to understand the effect of vitamin B12 deficiency on neuropathic ocular pain (NOP) and symptoms in patients with dry eye disease (DED). METHODS: Patients with severe DED (without receiving topical artificial tears treatment) and ocular pain were enrolled (n = 90). Patients with severe DED and vitamin B12 deficiency (group 1, n = 45) received parenteral vitamin B12 supplement + topical treatment (artificial tears treatment + cyclosporine), and patients with severe DED and normal serum vitamin B12 level (group 2, n = 45) received only topical treatment (artificial tears treatment + cyclosporine). Patients were evaluated by the ocular surface disease index (OSDI) questionnaire, 3rd question (have you experienced painful or sore eyes during last week?) score of OSDI as a pain determiner and pain frequency measure), tear break up time (TBUT), and Schirmer's type 1 test. We compared the groups' OSDI, TBUT, and Schirmer's test recordings at the first visit and after 12 weeks retrospectively. RESULTS: The OSDI score, 3rd OSDI question score, TBUT, and Schirmer's test results improved after 12 weeks (p < 0.001 for each group). The mean vitamin B12 level at enrollment was 144.24 ±43.36 pg/ml in group 1 and 417.53 ±87.22 pg/ml in group 2. The mean vitamin B12 level in group 1 reached to 450 ±60.563 pg/ml after 12 weeks of treatment. The mean score changes between the groups were not statistically significant; however, the decrease in the OSDI questionnaire score (-30.80 ±5.24) and 3rd OSDI question score (-2.82 ±0.53) were remarkable in group 1 (Table 2). The mean TBUT increase was +7.98 ±2.90 s and Schirmer's test result increase was +12.16 ±2.01 mm in group 1. The mean TBUT increase was +6.18 ±1.49 s and Schirmer's test result increase was +6.71 ±1.47 mm in group 2. CONCLUSIONS: These findings indicate that vitamin B12 deficiency is related with NOP. It may be important to consider measuring the serum vitamin B12 level in patients with severe DED presenting with resistant ocular pain despite taking topical treatment.

An 11-Year Review of Keratoplasty in a Tertiary Referral Center in Turkey: Changing Surgical Techniques for Similar Indications.

OBJECTIVES: Study aims to evaluate the indications and surgical techniques for corneal transplantation and to report changes in trends for preferred keratoplasty surgical techniques. METHODS: Clinical records of 815 consecutive corneal transplantations between January 1, 2004 and December 31, 2014 in Haydarpasa Numune Training and Research Hospital Eye Clinic were analyzed and classified into seven broad groups according to indications. Main outcome measures were change of leading indications and trends for surgical techniques. RESULTS: Leading indications for keratoplasty were keratoconus (KCN) (27.7%), bullous keratopathy (BK) (23%), postinfectious corneal scars (13.5%), regrafts (13.1%), corneal dystrophies (12.1%), and noninfectious corneal scars (5.4%). Regrafts were the only indication with a significantly increasing trend (P<0.01). Since the introduction of lamellar keratoplasty (LK) techniques including deep anterior lamellar keratoplasty (DALK) and Descemet stripping automated endothelial keratoplasty (DSAEK), there was a significant increasing trend in number and percentage of both LK techniques (DALK; P=0.001 and P=0.007, and DSAEK; P<0.001 and P<0.001, respectively) and a significant corresponding decline in the percentage of penetrating keratoplasty (PK) (P<0.01). Similarly, DALK and DSAEK replaced PK as the preferred surgical technique for KCN and BK indications, (P=0.007 and P=0.01, respectively). Although PK was the most common surgical technique over the 11-year period (54.7%), both anterior and posterior LK techniques showed an emerging trend as the procedures of choice when indicated. CONCLUSIONS: No major shift was observed in the clinical indications for corneal transplantation over the previous 11 years, except for regrafts. Lamellar keratoplasty techniques largely overtook the PK technique, but PK was still the overall preferred technique in the era when both LK techniques were used.

Scheimpflug camera combined with placido-disk corneal topography and optical biometry for intraocular lens power calculation.

The purpose of this study was to compare the keratometry (K) values obtained by the Scheimpflug camera combined with placido-disk corneal topography (Sirius) and optical biometry (Lenstar) for intraocular lens (IOL) power calculation before the cataract surgery, and to evaluate the accuracy of postoperative refraction. 50 eyes of 40 patients were scheduled to have phacoemulsification with the implantation of a posterior chamber intraocular lens. The IOL power was calculated using the SRK/T formula with Lenstar K and K readings from Sirius. Simulated K (SimK), K at 3-, 5-, and 7-mm zones from Sirius were compared with Lenstar K readings. The accuracy of these parameters was determined by calculating the mean absolute error (MAE). The mean Lenstar K value was 44.05 diopters (D) ±1.93 (SD) and SimK, K at 3-, 5-, and 7-mm zones were 43.85 ± 1.91, 43.88 ± 1.9, 43.84 ± 1.9, 43.66 ± 1.85 D, respectively. There was no statistically significant difference between the K readings (P = 0.901). When Lenstar was used for the corneal power measurements, MAE was 0.42 ± 0.33 D, but when simK of Sirius was used, it was 0.37 ± 0.32 D (the lowest MAE (0.36 ± 0.32 D) was achieved as a result of 5 mm K measurement), but it was not statistically significant (P = 0.892). Of all the K readings of Sirius and Lenstar, Sirius 5-mm zone K readings were the best in predicting a more precise IOL power. The corneal power measurements with the Scheimpflug camera combined with placido-disk corneal topography can be safely used for IOL power calculation.

Plateletcrit in Ocular Pseudoexfoliation Syndrome.

PURPOSE: The aim of this study was to compare all platelet markers, especially plateletcrit (PCT, total platelet mass), in patients with and without ocular pseudoexfoliation (PEX) syndrome. METHODS: One hundred six patients with ocular PEX syndrome (study group) and 106 individuals without ocular PEX syndrome (control group) were enrolled in this retrospective case-control study. The biochemical/hematological laboratory results of both the study and control groups were analyzed by a clinician blinded to the group assignments. The main outcome measures were the PCT, platelet count (PLT), mean platelet volume (MPV), and platelet distribution width (PDW). RESULTS: The mean PCT in the study and control groups were 0.206%±0.520% and 0.171%±0.410%, respectively (P<0.001), and the mean PDW in the study and control groups were 16.12%±1.21% and 14.68%±1.40%, respectively (P<0.001). There were no differences in the MPV or mean PLT (P=0.138 and P=0.055, respectively). The PCT cutoff value was 0.180 (area under the receiver operating characteristics curve, 0.706; P<0.001; 65% sensitivity; 74% specificity). CONCLUSIONS: The PCT and PDW were significantly higher in patients with than without ocular PEX syndrome. These increased parameters may cause microvascular blood flow resistance and the heightened inflammatory response caused by excessive platelet activity, as with other cardiovascular diseases, and may also decrease aqueous humor outflow in ocular PEX syndrome.

Clinical outcomes of trabeculectomy vs. Ahmed glaucoma valve implantation in patients with penetrating keratoplasty : (Trabeculectomy vs. Ahmed galucoma valve in patients with penetrating keratoplasty).

The aim of this study was to compare the visual outcomes, intraocular pressure (IOP), and endothelial cell loss caused by trabeculectomy (TRAB) and Ahmed glaucoma valve (AGV) implantation in patients who had previously undergone penetrating keratoplasty (PKP). The data from all patients who underwent surgical treatment of glaucoma after PKP were reviewed at the Cornea Department of Haydarpasa Numune Education and Research Hospital. Eighteen patients who had undergone surgical treatment of glaucoma after PKP were included in this retrospective study. Time between PKP and glaucoma surgeries, visual acuity results, IOP results, endothelial cell counts (ECC) before the surgery, at 1st, 6th, and 12th month of surgery were recorded. Differences between two groups were evaluated. Mean loss of ECC was 315 cells/mm(2) in the AGV group and 197 cells/mm(2) in TRAB group at 12th month of glaucoma surgery. The difference between endothelial cell loss at 12th month of surgery was statistically significant and higher in AGV group (p < 0.001). The decrease in IOP was 64.2 % in AGV group and 46.9 % in TRAB group at 12th month of surgery. Both differences were statistically significant between 2 groups (p = 0.001, 0.001). TRAB successfully decreased both the IOP and endothelial cell loss in patients with post-PKP glaucoma. Ahmed glaucoma valve had a significantly better IOP lowering but higher endothelial cell loss effect.

In-vivo corneal biomechanical analysis of unilateral keratoconus.

AIM: To evaluate and compare corneal biomechanical findings measured by ocular response analyzer, topographic and pachymetric findings in patients with unilateral keratoconus patients and healthy controls. METHODS: This is an observational, case-control study. Patients with keratoconus in one eye and forme fruste keratoconus in the fellow eye were compared with sex and age matched with controls healthy subjects. All subjects were evaluated with rotating scheimpflug imaging system. The receiver-operating-characteristic curves were analyzed to evaluate the sensitivity and specificity of the parameters. RESULTS: Twenty-seven patients with keratoconus in one eye and forme fruste keratoconus in the fellow eye were compared with 40 eyes of 40 normal subjects. Corneal hysteresis (CH) was 8.0±1.7 mm Hg in keratoconus group, 8.3±1.6 mm Hg in forme fruste keratoconus group, and 9.8±1.6 mm Hg in control groups (P=0.54 between keratoconus and forme fruste keratoconus groups, P<0.01 between control group and other groups). Corneal resistance factor (CRF) was 7.1±2.2 mm Hg in keratoconus group, 7.8±1.2 mm Hg in forme fruste keratoconus group and 9.9±1.5 mm Hg in control group (P<0.001 between control group and other groups). Using receiver-operating-characteristic analysis, the area under curve values of the parameters to distinguish forme fruste keratoconus from control subjects were: CH (0.768), CRF (0.866). Best cut-off points were 9.3 mm Hg and 8.8 mm Hg for CH and CRF respectively. CONCLUSION: Ocular response analyzer parameters (CH and CRF) are found to be significantly lower in forme fruste keratoconus patients compared to normal control subjects.

Visual acuity and endothelial cell density with respect to the graft thickness in Descemet's stripping automated endothelial keratoplasty: one year results.

AIM: To evaluate the visual acuity and endothelial cell density according to the thickness in Descemet's stripping automated endothelial keratoplasty (DSAEK) one year after surgery. METHODS: DSAEK patients' data were reviewed. Thirty-seven eyes of 37 patients who underwent DSAEK for pseudophakic bullous keratopathy (PBK) were included in this study. Graft thickness was measured with optical coherence tomography (OCT) 12mo after DSAEK. Eyes were divided into 3 groups based on the graft thickness: thick (>200 µm), medium-thick (150-200 µm) and thin (<150 µm). Best corrected visual acuity (BCVA), endothelial cells density (ECD) and complications were assessed and comparisons were done between groups. RESULTS: There was no significant difference in age, sex, preoperative BCVA, or follow-up period between DSAEK groups. At postoperative 12mo, mean BCVA was 0.28±0.10 in thick graft group, 0.52±0.08 in medium-thick graft group, and 0.72±0.06 in thin graft group. Thin grafts showed better postoperative BCVA as compared with the medium-thick and thick grafts (P=0.001). Thick graft group had 1637.44±88.19-mm(2), medium thick graft had 1764.50±34.28-mm(2) and thin graft group had 1845.30±65.62-mm(2) ECD at 12mo after the surgery. Thin graft group had better ECD at 12mo after surgery (P=0.001). CONCLUSION: Thin grafts after DSAEK ensure better visual rehabilitation. Eyes with thin grafts had significantly lesser loss of ECD compared to eyes with medium-thick and thick grafts one year after surgery.

Corneal biomechanical properties in eyes with no previous surgery, with previous penetrating keratoplasty and with deep anterior lamellar keratoplasty.

PURPOSE: To compare the biomechanical properties of the cornea in eyes with no previous surgery, with keratoconus with previous penetrating keratoplasty (PK) and with keratoconus with previous deep anterior lamellar keratoplasty (DALK) using the Reichert Ocular Response Analyzer (ORA). METHODS: One hundred twenty eyes of 120 patients were included in this prospective comparative study. Forty eyes were with no previous ocular surgery (group 1), 40 eyes were with previous PK for keratoconus (group 2), and 40 eyes were with previous DALK for keratoconus (group 3). Corneal hysteresis (CH) and the corneal resistance factor (CRF) were measured with ORA. RESULTS: The CH and CRF values in group 2 were significantly lower than in group 1 and group 3 (p = 0.001). The CH and CRF values were similar in group 1 and group 3. There was no statistically significant difference between group 1 and 3. CONCLUSION: Although the post-PK keratoconus cornea has weaker biomechanical properties, post-DALK keratoconus cornea is similar to normal cornea. A cornea weakened by keratoconus can be strengthened with lamellar keratoplasty.

Comparison of contrast sensitivity and visual acuity between deep anterior lamellar keratoplasty and penetrating keratoplasty in patients with keratoconus.

AIM: To evaluate postoperative visual acuity and contrast sensitivity results following deep anterior lamellar keratoplasty (DALK) and penetrating keratoplasty (PK) in patients with keratoconus (KC). METHODS: All the patients' records with KC who had PK or DALK surgery between May 2010 and May 2011 were retrospectively reviewed. Sixty patients who underwent successful corneal transplantation for KC: 30 eyes underwent DALK and 30 eyes underwent PK were included in this study. Preoperative and postoperative mean logarithm of the minimum angle of resolution (logMAR) uncorrected visual acuity (UCVA), logMAR best spectacle-corrected visual acuity (BSCVA) and intraocular pressure (IOP) were evaluated. Contrast sensitivity tests (CS) were done preoperative and 2 months after all sutures had removed. All surgeries were performed under regional anesthesia (retrobulbar anesthesia) by 1 surgeon (B.K.) who was experienced in penetrating and lamellar keratoplasty techniques. RESULTS: The mean age of the DALK group was 29.67±4.95 (range 18-40) years and the PK group was 28.7±3.53 (range 18-39) years. Preoperatively there was no significant difference in the logMAR UCVA, logMAR BSCVA and IOP between the DALK (1.281±0.56; 0.97±0.85; 12.07±2.12mmHg) and PK (1.34±0.21; 0.98±0.21; 13±2.12mmHg) groups. One-year after surgery there was no significant difference in the mean logMAR UCVA and IOP between the DALK (0.46±0.37; 11.73±2.1mmHg) and PK (0.38±0.21; 12±2.12mmHg) groups. The mean contrast sensitivity was evaluated by CC-100 Topcon LCD at 1.5, 2.52, 4.23, 7.10 and 11.91 cycles per degree (cs/deg) spatial frequencies before and 2 months after the all sutures had removed. CONCLUSION: All patients with keratoconus in both DALK and PK groups performed good visual function postoperatively. The mean contrast sensitivity increased considerably at all spatial frequencies compared with preoperative levels in the DALK and PK groups. The mean post-operative evaluation of contrast sensitivity measurements was not significantly different between the two groups.