Effect of Reduced Meal Frequency during Ramadan Fasting on Retinal and Choroidal Thickness.

PURPOSE: To evaluate the effects of Ramadan fasting on central foveal thickness (CFT) and subfoveal choroidal thickness (SFCT) in healthy individuals using enhanced depth imaging optical coherence tomography (EDI-OCT). MATERIALS AND METHODS: The EDI-OCT scans of 42 healthy individuals obtained after about 12 hours of fasting on at least the twenty-first consecutive day of fasting were compared to scans of the same patients taken one month after the last day they had fasted. RESULTS: CFT values were similar for both time periods (p > 0.05). The SFCT was significantly higher after consecutive fasting days towards the end of Ramadan, compared to the SFCT after one month of no fasting (one month after Ramadan ended) (p < 0.001). CONCLUSIONS: Ramadan fasting may lead to a significant increase in subfoveal choroidal thickness without affecting the central foveal thickness.

The Effect of Smoking on Corneal Endothelial Cells.

PURPOSE: To investigate the effect of chronic cigarette smoking on the endothelial cells of the cornea via non-contact specular microscopy. METHOD: In this prospective, cross-sectional study, 25 eyes of 25 chronic smokers and 21 eyes of 21 age-matched, healthy non-smokers were enrolled. The Fagerström Test for Nicotine Dependence on Cigarettes was used to determine the nicotine dependency level. The level of cotinine, a major metabolite of nicotine, was measured in urine samples from the control group to detect whether they were passively affected by cigarette smoke. All participants underwent measurement of tear break-up time (TBUT), central corneal thickness (CCT), and axial length. Endothelial cell density and endothelial cell morphology were evaluated by non-contact specular microscopy. RESULTS: On average, the cigarette smokers consumed 19.2 ± 8.3 cigarettes per day and had been smoking for 14.5 ± 6.8 years. The mean TBUT value was significantly lower in the smoker group compared to the non-smoker group (p < 0.05). No statistically significant difference was found in the mean CCT, mean endothelial cell density, or parameters of endothelial cell morphology between smokers and non-smokers. CONCLUSION: This study showed that cigarette smoking seems to affect the TBUT value but no effects were found on the parameters of corneal endothelial cells.

Repeatability of contrast sensitivity testing in patients with age-related macular degeneration, glaucoma, and cataract.

PURPOSE:: To analyze the intrasession and intersession repeatability of contrast sensitivity (CS) measurements in patients with glaucoma, cataract, or age-related macular degeneration (AMD) and healthy controls. METHODS:: CS measurements were performed using the OPTEC-Functional Vision Analyzer (FVA), which uses a standardized and closed (view-in) system. Measurements for patients with glaucoma, cataract, or AMD and healthy controls were repeated within 30 minutes (intrasession) and during two sessions (intersession), separated by one week to one month. Test-retest reliability and correlation were measured using the intraclass correlation coefficient (ICC) and coefficient of repeatability (COR). RESULTS:: Ninety subjects (90 eyes) with visual acuity of 0.17 logMAR or higher in the cataract group or 0.00 logMAR in the other groups were included. During the first session, the ICC values were 0.87, 0.90, 0.76, and 0.69, and COR values were 0.24, 0.20, 0.38, and 0.25 for the control, glaucoma, cataract, and AMD groups, respectively. The reliability scores significantly improved during the second session, except in the glaucoma group. There was an acceptable floor effect and no ceiling effect at higher frequencies in the glaucoma and AMD groups. CONCLUSION:: In subjects with good visual acuity, the FVA system is useful for evaluating CS and demonstrates good repeatability, as shown by ICC and COR. Because there is no ceiling effect, this system is beneficial for evaluation of early changes in CS, particularly in patients with glaucoma or AMD.

Repeatability of contrast sensitivity testing in patients with age-related macular degeneration, glaucoma, and cataract / Reprodutibilidade dos escores de sensibilidade ao contraste em pacientes com degeneração macular relacionadas à idade, glaucoma e catarata

ABSTRACT Purpose: To analyze the intrasession and intersession repeatability of contrast sensitivity (CS) measurements in patients with glaucoma, cataract, or age-related macular degeneration (AMD) and healthy controls. Methods: CS measurements were performed using the OPTEC-Functional Vision Analyzer (FVA), which uses a standardized and closed (view-in) system. Measurements for patients with glaucoma, cataract, or AMD and healthy controls were repeated within 30 minutes (intrasession) and during two sessions (intersession), separated by one week to one month. Test-retest reliability and correlation were measured using the intraclass correlation coefficient (ICC) and coefficient of repeatability (COR). Results: Ninety subjects (90 eyes) with visual acuity of 0.17 logMAR or higher in the cataract group or 0.00 logMAR in the other groups were included. During the first session, the ICC values were 0.87, 0.90, 0.76, and 0.69, and COR values were 0.24, 0.20, 0.38, and 0.25 for the control, glaucoma, cataract, and AMD groups, respectively. The reliability scores significantly improved during the second session, except in the glaucoma group. There was an acceptable floor effect and no ceiling effect at higher frequencies in the glaucoma and AMD groups. Conclusion: In subjects with good visual acuity, the FVA system is useful for evaluating CS and demonstrates good repeatability, as shown by ICC and COR. Because there is no ceiling effect, this system is beneficial for evaluation of early changes in CS, particularly in patients with glaucoma or AMD.

RESUMO Objetivo: Analisar a reprodutibilidade intrassessão e intersessão das medidas de sensibilidade ao contraste (CS) em pacientes com degeneração macular relacionada à idade (AMD), glaucoma e catarata. Método: As medidas de CS foram feitas pelo OPTEC-Funcional Visão Analyzer (FVA), que utiliza um sistema padronizado e fechado de avaliação da acuidade visual. Medidas em pacientes com AMD, glaucoma, catarata e nos controles saudáveis foram repetidas no prazo de 30 minutos (intrassessão) em duas visitas (intersessão), separadas por uma semana a um mês. A confiabilidade e correlação teste-reteste foram calculados por meio do coeficiente de correlação intraclasse (ICC) e coeficiente de reprodutibilidade (COR). Resultados: Noventa olhos de 90 indivíduos foram recrutados com acuidade visual de 0,17 logMAR ou melhor em catarata e 0,00 logMAR nos outros grupos. A confiabilidade da CS na primeira visita dos grupos normal, glaucoma, catarata e AMD foram, respectivamente, ICC 0,87; 0,90; 0,76; 0,69, e COR 0,24; 0,20; 0,38; 0,25. Os índices de confiabilidade foram significativamente melhorados nas segundas visitas, exceto no grupo glaucoma. Houve um efeito chão aceitável e nenhum efeito teto em frequências mais altas nos grupos glaucoma e AMD. Conclusões: Em indivíduos com boa acuidade visual, o sistema FVA de avaliação da CS é útil e apresenta boa confiabilidade, como mostrado pelas análises de ICC e COR. Por não apresentar efeito teto, este sistema parece ser benéfico para a avaliação das alterações precoces de CS, especialmente no glaucoma e AMD.

Non-invasive assessment of corneal and conjunctival deterioration in soft contact lens users using anterior segment optical coherence tomography.

BACKGROUND: The aim was to evaluate the corneal and bulbar conjunctival thicknesses of soft contact lens (SCL) wearers using anterior segment optical coherence tomography (AS-OCT). METHODS: The epithelial and overall thicknesses of both the central cornea and the infero-temporal bulbar conjunctiva of SCL wearers (30 subjects) were obtained by Cirrus HD-OCT and compared with those of refraction-matched controls (30 subjects) and patients with emmetropia (30 subjects). RESULTS: The mean corneal epithelial thicknesses in SCL wearing, spectacle-wearing and emmetropic groups were 48.97 ± 5.45, 52.18 ± 4.84 and 53.18 ± 5.05 µm, respectively. The corneal epithelium of members of the SCL group was significantly thinner than in both the spectacles and emmetropic groups (p = 0.044 and 0.006, respectively), whereas the central corneal thickness did not differ between groups (p = 0.210). The mean conjunctival epithelial thicknesses in SCL, spectacles and emmetropic groups were 41.50 ± 7.75, 54.33 ± 8.39 and 49.10 ± 7.11 µm, respectively. Conjunctival epithelium in the SCL group was significantly thinner than in both spectacle-wearing and emmetropic groups (p < 0.001 and p = 0.001, respectively). The conjunctiva was significantly thinner in the SCL group compared to the spectacles group (p = 0.001) but not the emmetropic group. CONCLUSIONS: Contact lens wear is related to thinning of both corneal and conjunctival layers. AS-OCT is a non-invasive and clinically applicable technique for assessing the involvement of the cornea and conjunctiva in contact lens wearers.

Noninvasive assessment of the retina and the choroid using enhanced-depth imaging optical coherence tomography shows microvascular impairments in childhood obesity.

PURPOSE: To evaluate the retinal vascular diameters and macular and subfoveal choroidal thicknesses of obese and nonobese children using enhanced-depth imaging spectral domain optical coherence tomography (EDI SD-OCT). METHODS: The retinal vascular diameters of the 4 largest retinal arterioles and venules and macular and subfoveal choroidal thickness measurements of 40 obese children (body mass index [BMI] z score above +2.0 standard deviations) were obtained by EDI SD-OCT and compared with those of 40 age- and sex-matched nonobese children. Anthropometric measures, including weight and height, were also obtained. BMI z score was defined using standardized protocols. RESULTS: The mean BMI z scores of obese children were 2.59 ± 0.62; of nonobese children, -0.20 ± 0.92. The mean diameter of retinal arterioles was significantly smaller (P = 0.002) in obese children compared to nonobese children, whereas the mean diameter of retinal venules was larger (P = 0.008). The macular and subfoveal choroidal thicknesses were significantly thinner (P = 0.031 and 0.014, resp.) in obese children compared to nonobese children. CONCLUSIONS: The narrower retinal arterioles, wider retinal venules, and thinner macular and subfoveal choroidal thicknesses in obese children seem to be associated with microvascular impairments in childhood obesity.

Effect of Topically Applied Azithromycin on Corneal Epithelial and Endothelial Apoptosis in a Rat Model of Corneal Alkali Burn.

PURPOSE: To investigate the antiapoptotic effect of topically administered azithromycin (AZM) on corneal epithelial and endothelial cells in a rat model of corneal alkali burn. METHODS: Twenty-four Wistar albino rats were divided into 4 equal groups as pseudovehicle (group 1), control (group 2), alkali burned (group 3), and treatment (group 4) groups. Alkali injury was induced only in the right corneas of rats belonging to groups 3 and 4 using 1N NaOH. The rats in group 3 and the rats in group 4 were respectively treated either with an artificial tear gel or with 1.5% AZM eye drops for 5 days. At the fifth day of the experiment, the apoptosis in the corneal epithelium and endothelium of all rats was assessed using a terminal dUTP nick-end labeling (TUNEL) assay. In addition, tumor necrosis factor-alpha (TNF-α) density in the corneal epithelium was measured in all rats. RESULTS: The mean numbers of TUNEL+ cells in the corneal epithelium and endothelium of rats in group 3 were 117.1 ± 23.8 and 34.6.± 11.3, respectively, whereas in group 4, they were 75.8 ± 15.7 and 14.7 ± 3.5, respectively. Also the mean TNF-α densities in the corneal epithelium in group 3 and group 4 were 2.65 ± 1.3 and 1.65 ± 1.1, respectively. There was a significant decrease in the mean number of TUNEL+ cells in the corneal epithelium and endothelium and in the mean TNF-α density in the corneal epithelium of rats in group 4, when compared with group 3. CONCLUSIONS: Topically applied AZM can decrease TNF-α-induced apoptosis in corneal alkali burn.

Does Retinal Neurodegeneration Seen in Diabetic Patients Begin in the Insulin Resistance Stage?

OBJECTIVES: To investigate whether retinal neurodegeneration and impairment in contrast sensitivity (CS), which have been demonstrated to begin in diabetic patients before the presence of signs of diabetic retinal vasculopathy, also occur in the stage of insulin resistance. MATERIALS AND METHODS: The average, minimum and sectoral (inferior, superior, inferonasal, superonasal, inferotemporal and superotemporal) thicknesses of the ganglion cell-inner plexiform layer (GCIPL) measured using optical coherence tomography were compared between an insulin-resistant group and control group in order to evaluate the presence of retinal neurodegeneration. The CS of the two groups was also compared according to the logarithmic values measured at spatial frequencies of 1.5, 3, 6, 12 and 18 cycles per degree in photopic light using functional acuity contrast test (FACT). RESULTS: Twenty-five eyes of 25 patients with insulin resistance (insulin resistant group) and 25 eyes of 25 healthy subjects (control group) were included in this study. There were no statistically significant differences between the two groups in any of the spatial frequencies in the FACT. The mean average GCIPL thickness and mean GCIPL thickness in the inferotemporal sector were significantly less in the insulin-resistant group when compared with the control group (mean average GCIPL thicknesses in the insulin-resistant and control groups were 83.6±4.7 µm and 86.7±3.7 µm respectively, p=0.01; mean inferotemporal GCIPL thicknesses in the insulin-resistant and control groups were 83±6.0 µm and 86.7±4.6 µm respectively, p=0.02). CONCLUSION: Although it may not lead to functional visual impairment such as CS loss, the retinal neurodegeneration seen in diabetic patients may begin in the insulin resistance stage.

Blood gas analyzer utility in evaluating oxygen kinetics of the aqueous humor.

PURPOSE: To measure the partial pressure of oxygen (PO2) and carbon dioxide (PCO2) and the pH of aqueous humor (AH) and arterial blood samples from rabbits using a blood gas analyzer. METHODS: Twenty New Zealand rabbits were anesthetized intramuscularly with ketamine and xylazine and were then allowed to breathe room air. Using a gas blood analyzer, arterial blood and AH samples were analyzed for PO2, PCO2, and pH. RESULTS: The mean arterial blood pressure was 87.14 ± 15.0 mmHg. The mean blood and AH PO2 were 95.18 ± 11.76 mmHg and 88.83 ± 9.92 mmHg, the mean blood and AH PCO2 were 25.86 ± 5.46 mmHg and 29.50 ± 5.36 mmHg, and the mean blood and AH pH were 7.38 ± 0.06 and 7.33 ± 0.09, respectively. CONCLUSIONS: The blood gas analyzer was easily employed to evaluate the aqueous humor in rabbits. When comparing the results of studies evaluating aqueous PO2, care should be taken to determine the methods used in these studies.

Blood gas analyzer utility in evaluating oxygen kinetics of the aqueous humor / Utilidade de um analisador sanguíneo de gás para a avaliação cinética do oxigênio no humor aquoso

Purpose: To measure the partial pressure of oxygen (PO2) and carbon dioxide (PCO2) and the pH of aqueous humor (AH) and arterial blood samples from rabbits using a blood gas analyzer. Methods: Twenty New Zealand rabbits were anesthetized intramuscularly with ketamine and xylazine and were then allowed to breathe room air. Using a gas blood analyzer, arterial blood and AH samples were analyzed for PO2, PCO2, and pH. Results: The mean arterial blood pressure was 87.14 ± 15.0 mmHg. The mean blood and AH PO2 were 95.18 ± 11.76 mmHg and 88.83 ± 9.92 mmHg, the mean blood and AH PCO2 were 25.86 ± 5.46 mmHg and 29.50 ± 5.36 mmHg, and the mean blood and AH pH were 7.38 ± 0.06 and 7.33 ± 0.09, respectively. Conclusion: Conclusions: The blood gas analyzer was easily employed to evaluate the aqueous humor in rabbits. When comparing the results of studies evaluating aqueous PO2, care should be taken to determine the methods used in these studies. .

Objetivo: Medir a pressão parcial de oxigênio (PO2) e dióxido de carbono (PCO2), e o pH de humor aquoso (AH) e de amostras de sangue arterial de coelhos. Método: Vinte coelhos New Zealand foram anestesiados por via intramuscular com cetamina e xilazina, em seguida, foram liberados a respirar o ar ambiente. Utilizando um analisador sanguíneo de gás, amostras de sangue arterial e AH foram analisadas para PO2, PCO2, e pH. Resultados: A pressão arterial média foi de 87,14 ± 15,0 mmHg. A PO2 média do sangue e AH foi 95,18 ± 11,76 mmHg e 88,83 ± 9,92 mmHg; a PCO2 média do sangue e AH foi de 25,86 ± 5,46 mmHg e 29,50 ± 5,36 mmHg; o pH médio do sangue e AH foi 7,38 ± 0,06 e 7,33 ± 0,09, respectivamente. Conclusões: O analisador de gases no sangue foi facilmente empregadas para avaliar o humor aquoso em coelhos. Quando se comparam os resultados de estudos que avaliaram PO2 do humor aquoso, deve ser tomado cuidado para determinar os métodos utilizados nestes estudos. .

Changes in retinal nerve fiber layer thickness after spinal surgery in the prone position: a prospective study / Alterações da espessura da camada de fibras nervosas da retina após cirurgia da coluna vertebral em pronação: estudo prospectivo / Alteraciones del espesor de la capa de fibras nerviosas de la retina después de la cirugía de la columna vertebral en pronación: estudio prospectivo

BACKGROUND AND OBJECTIVES: Changes in ocular perfusion play an important role in the pathogenesis of ischemic optic neuropathy. Ocular perfusion pressure is equal to mean arterial pressure minus intraocular pressure. The aim of this study was to evaluate the changes in the intraocular pressure and the retinal nerve fiber layer thickness in patients undergoing spinal surgery in the prone position. METHODS: This prospective study included 30 patients undergoing spinal surgery. Retinal nerve fiber layer thickness were measured one day before and after the surgery by using optical coherence tomography. Intraocular pressure was measured by tonopen six times at different position and time-duration: supine position (baseline); 10 min after intubation (Supine 1); 10 (Prone 1), 60 (Prone 2), 120 (Prone 3) min after prone position; and just after postoperative supine position (Supine 2). RESULTS: Our study involved 10 male and 20 female patients with the median age of 57 years. When postoperative retinal nerve fiber layer thickness measurements were compared with preoperative values, a statistically significant thinning was observed in inferior and nasal quadrants (p = 0.009 and p = 0.003, respectively). We observed a statistically significant intraocular pressure decrease in Supine 1 and an increase in both Prone 2 and Prone 3 when compared to the baseline. Mean arterial pressure and ocular perfusion pressure were found to be significantly lower in Prone 1, Prone 2 and Prone 3, when compared with the baseline. CONCLUSIONS: Our study has shown increase in intraocular pressure during spinal surgery in prone position. A statistically significant retinal nerve fiber layer thickness thinning was seen in inferior and nasal quadrants one day after the spinal surgery. .

JUSTIFICATIVA E OBJETIVOS: As alterações de perfusão ocular desempenham um papel importante na patogênese da neuropatia óptica isquêmica. A pressão de perfusão ocular é igual à pressão arterial média menos a pressão intraocular. O objetivo deste estudo foi avaliar as alterações da pressão intraocular e da espessura da camada de fibras nervosas da retina em pacientes submetidos à cirurgia da coluna vertebral em pronação. MÉTODOS: Este estudo prospectivo incluiu 30 pacientes submetidos à cirurgia da coluna vertebral. A espessura da camada de fibras nervosas da retina foi medida um dia antes e um depois da cirurgia, com o uso da tomografia de coerência óptica. A pressão intraocular foi medida seis vezes com o Tonopen e o tempo de duração em posições diferentes: em supinação (basal), 10 minutos após a intubação (Supinação 1); após a pronação aos 10 minutos (Pronação 1), 60 minutos (Pronação 2) e 120 minutos (Pronação 3) e logo após a supinação no período pós-operatório (Supinação 2). RESULTADOS: Nosso estudo envolveu 10 pacientes do sexo masculino e 20 do feminino, com média de 57 anos. No pós-operatório, quando as medidas da espessura da camada de fibras nervosas da retina foram comparadas com os valores do pré-operatório, um afinamento estatisticamente significativo da retina foi observado nos quadrantes nasais e inferiores (p = 0,009 e p = 0,003, respectivamente). Observamos uma diminuição da pressão intraocular estatisticamente significante em Supinação 1 e um aumento em ambos momentos Pronação 2 e Pronação 3, em comparação com os valores basais. A pressão arterial média e a pressão de perfusão ocular foram significativamente mais baixas em Pronação 1, Pronação 2 e Pronação 3, em comparação com os valores basais. CONCLUSÕES: Nosso estudo mostrou aumento da pressão intraocular durante a cirurgia da coluna vertebral em pronação. Um afinamento estatisticamente significante da espessura da camada de fibras nervosas da retina foi observado ...

JUSTIFICACIÓN Y OBJETIVOS: Las alteraciones en la perfusión ocular desempeñan un rol importante en la patogénesis de la neuropatía óptica isquémica. La presión de perfusión ocular es igual a la presión arterial media menos la presión intraocular. El objetivo de este estudio fue evaluar las alteraciones de la presión intraocular y del espesor de la capa de fibras nerviosas de la retina en pacientes sometidos a cirugía de la columna vertebral en pronación. MÉTODOS: Este estudio prospectivo incluyó a 30 pacientes sometidos a cirugía de la columna vertebral. El espesor de la capa de fibras nerviosas de la retina se midió un día antes y uno después de la cirugía, con la tomografía de coherencia óptica. La presión intraocular se midió 6 veces con tonopen y el tiempo de duración en posiciones diferentes: en supinación (basal), 10 min después de la intubación (supinación 1); después de la pronación a los 10 min (pronación 1), 60 min (pronación 2) y 120 min (pronación 3), y justo después de la supinación en el período postoperatorio (supinación 2). RESULTADOS: Nuestro estudio contó con la participación de 10 pacientes del sexo masculino y 20 del femenino, con un promedio de edad de 57 años. En el postoperatorio, cuando las medidas del espesor de la capa de fibras nerviosas de la retina fueron comparadas con los valores del preoperatorio, se observó un adelgazamiento estadísticamente significativo de la retina en los cuadrantes nasales e inferiores (p = 0,009 y p = 0,003, respectivamente). Observamos una disminución de la presión intraocular estadísticamente significativa en supinación 1 y un aumento en pronación 2 y 3, en comparación con los valores basales. La presión arterial media y la presión de perfusión ocular fueron significativamente más bajas en pronación 1, pronación 2 y pronación 3, en comparación con los valores basales. CONCLUSIONES: Nuestro estudio mostró un aumento de la presión intraocular durante la cirugía de la columna vertebral ...

[Changes in retinal nerve fiber layer thickness after spinal surgery in the prone position: a prospective study]. / Alterações da espessura da camada de fibras nervosas da retina após cirurgia da coluna vertebral em pronação: estudo prospectivo.

BACKGROUND AND OBJECTIVES: Changes in ocular perfusion play an important role in the pathogenesis of ischemic optic neuropathy. Ocular perfusion pressure is equal to mean arterial pressure minus intraocular pressure. The aim of this study was to evaluate the changes in the intraocular pressure and the retinal nerve fiber layer thickness in patients undergoing spinal surgery in the prone position. METHODS: This prospective study included 30 patients undergoing spinal surgery. Retinal nerve fiber layer thickness were measured one day before and after the surgery by using optical coherence tomography. Intraocular pressure was measured by tonopen six times at different position and time-duration: supine position (baseline); 10min after intubation (Supine 1); 10 (Prone 1), 60 (Prone 2), 120 (Prone 3)min after prone position; and just after postoperative supine position (Supine 2). RESULTS: Our study involved 10 male and 20 female patients with the median age of 57 years. When postoperative retinal nerve fiber layer thickness measurements were compared with preoperative values, a statistically significant thinning was observed in inferior and nasal quadrants (p=0.009 and p=0.003, respectively). We observed a statistically significant intraocular pressure decrease in Supine 1 and an increase in both Prone 2 and Prone 3 when compared to the baseline. Mean arterial pressure and ocular perfusion pressure were found to be significantly lower in Prone 1, Prone 2 and Prone 3, when compared with the baseline. CONCLUSIONS: Our study has shown increase in intraocular pressure during spinal surgery in prone position. A statistically significant retinal nerve fiber layer thickness thinning was seen in inferior and nasal quadrants one day after the spinal surgery.

Evaluation of choroidal thickness in patients with obstructive sleep apnea/hypopnea syndrome.

Purpose: To compare the subfoveal choroidal thickness (SFCT) of patients with different severities of obstructive sleep apnea/hypopnea syndrome (OSAHS) and normal controls via enhanced depth imaging optical coherence tomography (EDI-OCT). Methods: In this retrospective, case-control study, 49 eyes from 49 patients that had undergone polysomnography were included. SFCT of the horizontal and vertical line scans were manually measured for all eyes based on EDI-OCT images. Two separate analyses were performed according to different apnea/hypopnea index (AHI) groupings. Initial testing was conducted using non-OSAHS, mild OSAHS (5≤AHI<15), moderate OSAHS (15≤AHI<30), and severe OSAHS (AHI≥30) patient groupings, while secondary testing used non-OSAHS, mild OSAHS (5≤AHI<15), and moderate/severe OSAHS (AHI≥15) patient groupings. Results: The mean SFCT was 314.5 µm in the non-OSAHS patients (n=14), 324.5 µm in the mild OSAHS patients (n=15), 269.3 µm in the moderate OSAHS patients (n=11), and 264.3 µm in the severe OSAHS patients (n=9). SFCT between the four groups revealed no significant differences despite a trend towards slight thinning in the severe group (P=0.08). When the moderate and severe groups were merged and compared with the mild OASHS and non-OSAHS groups, SFCT of the moderate/severe group was found to be significantly thinner than that of the mild group (P=0.016). A negative significant correlation was found between SFCT and AHI in OSAHS patients (r=0.368, P=0.033). Conclusions: In patients with moderate/severe OSAHS, EDI-OCT revealed a thinned SFCT. Other accompanying systemic or ocular diseases may induce perfusion and oxygenation deficiency in eyes of OSAHS patients. Further studies are required in order to determine the exact relationships between ocular pathologies and clinical grades of OSAHS.

Evaluation of choroidal thickness in patients with obstructive sleep apnea/hypopnea syndrome / Avaliação da espessura da coroide em pacientes com síndrome da apnéia/hipopnéia obstrutiva do sono

Purpose: To compare the subfoveal choroidal thickness (SFCT) of patients with different severities of obstructive sleep apnea/hypopnea syndrome (OSAHS) and normal controls via enhanced depth imaging optical coherence tomography (EDI-OCT). Methods: In this retrospective, case-control study, 49 eyes from 49 patients that had undergone polysomnography were included. SFCT of the horizontal and vertical line scans were manually measured for all eyes based on EDI-OCT images. Two separate analyses were performed according to different apnea/hypopnea index (AHI) groupings. Initial testing was conducted using non-OSAHS, mild OSAHS (5≤AHI<15), moderate OSAHS (15≤AHI<30), and severe OSAHS (AHI≥30) patient groupings, while secondary testing used non-OSAHS, mild OSAHS (5≤AHI<15), and moderate/severe OSAHS (AHI≥15) patient groupings. Results: The mean SFCT was 314.5 μm in the non-OSAHS patients (n=14), 324.5 μm in the mild OSAHS patients (n=15), 269.3 μm in the moderate OSAHS patients (n=11), and 264.3 μm in the severe OSAHS patients (n=9). SFCT between the four groups revealed no significant differences despite a trend towards slight thinning in the severe group (P=0.08). When the moderate and severe groups were merged and compared with the mild OASHS and non-OSAHS groups, SFCT of the moderate/severe group was found to be significantly thinner than that of the mild group (P=0.016). A negative significant correlation was found between SFCT and AHI in OSAHS patients (r=0.368, P=0.033). Conclusions: In patients with moderate/severe OSAHS, EDI-OCT revealed a thinned SFCT. Other accompanying systemic or ocular diseases may induce perfusion and oxygenation deficiency in eyes of OSAHS patients. Further studies are required in order to determine the exact relationships between ocular pathologies and clinical grades of OSAHS. .

Objetivo: Comparar a espessura da coróide subfoveal (subfoveal choroidal thickness - SFCT) de pacientes com diferentes gravidades de síndrome de apnéia/hipopnéia obstrutiva do sono (obstructive sleep apnea/hypopnea syndrome - OSAHS) e controles normais por meio da tomografia de coerência óptica com profundidade de imagem aprimorada (enhanced depth imaging optical coherence tomography - EDI-OCT). Métodos: Neste estudo retrospectivo caso-controle, foram incluídos 49 olhos de 49 pacientes submetidos a polissonografia. A espessura da coroide subfoveal nas linhas horizontais e verticais de rastreamento foi medida manualmente em todos os olhos, com base nas imagens de EDI-OCT. De acordo com o índice de apnéia/hipopnéia (AHI), duas análises separadas foram realizadas: com dados de pacientes sem OSAHS, com OSAHS leve (5≤AHI<15), com OSAHS moderado (15≤AHI<30) e com OSAHS grave (AHI≥30) e com dados de pacientes sem OSAHS, com OSAHS leve (5≤AHI<15) e com OSAHS moderada e grave (AHI≥15). Resultados: A média de SFCT foi de 314,5 μm nos pacientes sem OSAHS (n=14), 324,5 μm em pacientes com OSAHS leve (n=15), 269,3 μm em pacientes com OSAHS moderada (n=11) e 264,3 μm em pacientes com OSAHS grave (n=9). Não houve diferença significativa entre a SFCT dos quatro grupos, apesar do discreto afinamento no grupo severo (p=0,08). Quando os grupos moderados e graves foram fundidos e comparados com os grupos sem OSAHS e com OSAHS leves, SFCT do grupo moderado/ grave foi significativamente mais fino do que o do grupo leve (p=0,016). Foi encontrada uma correlação negativa significativa entre SFCT e AHI em pacientes com OSAHS (r=0,368, p=0,033). Conclusões: Em pacientes com OSAHS moderada/grave, a EDI-OCT revelou um SFCT afinado. Outras doenças sistêmicas ou oculares associadas podem induzir a deficiência ...

Relationship between raised intraocular pressure and ischemia-modified albumin in serum and humor aqueous: a pilot study in rabbits.

AIM: We evaluated the relationship between increased intraocular pressure (IOP), ischemia-modified albumin levels in serum (IMA-s) and in humor aqueous (IMA-HA) in rabbits. METHODS: Twenty-five albino New Zealand rabbits weighing between 2.0 and 2.8 kg were used in this pilot study. With permission from Canakkale Onsekiz Mart University Animal Ethics Committee, the IOP of both eyes of each rabbit were recorded with a Tonopen (Tono-Pen XL, Reichart Inc., Depew, NY, USA) after the application of topical proparacaine 0.5% HCl anesthesia. Blood (4 mL) was collected from the marginal ear vein and an intracameral injection of 2.3 mg/mL sodium hyaluronate and subconjunctival dexamethasone was given in the right eye. Anterior chamber aqueous fluid was obtained using a limbal approach with a 27 gauge needle from both eyes. The left eyes were used as controls. IOP was measured on the 1(st), 3(rd) and 10(th) day after the initial injection, with Tonopen, IMA-s levels and IMA-HA examined simultaneously. RESULTS: Before the injections, IOP was 11.4±3.0 mm Hg in the right eye and 11.3±3.1 mm Hg in the left eye (P>0.05). There was a statistically significant difference between IMA-s levels before the IOP increase (IMA-s0) and IMA-s levels on the 1(st) and 3(rd) days after the increase in IOP (P=0.012 and P=0.01, respectively). No difference was observed between IMA-s0 and serum IMA levels on the 10(th) day (IMA-s10) after IOP increase (P=0.989). IMA-HA in the right eye in the first day after the injection was positively correlated with IOP (r=0.748; P=0.02). No other correlation is found between any other parameter with IMA-HA levels at any test time. A statistically significant positive correlation was observed between IMA-s values and IOP on the 1(st) and 3(rd) days (r=0.398, P=0.04 and r=0.382, P=0.04, respectively). There was no correlation between IMA-s levels and increased IOP on the 10(th) day after IOP increase (r=0.026, P=0.902). CONCLUSION: IMA may be an important indicator of acute damage caused by diseases involving ischemic damage to the eye, especially in case of increased intraocular pressure.

Protective effect of hesperetin and naringenin against apoptosis in ischemia/reperfusion-induced retinal injury in rats.

PURPOSE: Hesperetin and naringenin are naturally common flavonoids reported to have antioxidative effects. This study was performed to investigate whether either hesperetin or naringenin has a protective effect against apoptosis on retinal ischemia/reperfusion (I/R) injury. METHODS: Retinal I/R was induced by increasing the intraocular pressure to 150 mmHg for 60 minutes. Thirty-three male Wistar albino rats were randomised into 5 groups named control, I/R + sham, I/R + solvent (DMSO), I/R + hesperetin, and I/R + naringenin. Animals were given either hesperetin, naringenin, or the solvent intraperitoneally immediately following reperfusion. Thickness of retinal layers and retinal cell apoptosis were detected by histological analysis, tunel assay, and immunohistochemistry assay. RESULTS: Hesperetin and naringenin attenuated the I/R-induced apoptosis of retinal cells in the inner and outer nuclear cells of the rat retina. Retinal layer thickness of the naringenin treatment group was significantly thicker than that of the hesperetin, sham, and solvent groups (P < 0.05). CONCLUSIONS: Hesperetin and naringenin can prevent harmful effects induced by I/R injury in the rat retina by inhibiting apoptosis of retinal cells, which suggests that those flavanones have a therapeutic potential for the protection of ocular ischemic diseases.

The protective effects of dexmedetomidine against apoptosis in retinal ischemia/reperfusion injury in rats.

OBJECTIVE: Dexmedetomidine is an alpha 2 adrenoceptor agonist and can be used for postoperative sedation, analgesia and anesthesia-sparing properties. Furthermore, the neuroprotective effects against ischemia/reperfusion (I/R) injury in the central nervous system have been shown in experimental studies. This study aimed to investigate the protective effects of dexmedetomidine against apoptosis in retinal I/R injury in the rat. MATERIALS AND METHODS: Retinal I/R injury was induced by transient elevation of intraocular pressure. Eighteen animals were divided into three groups (n = 6): sham, I/R and treatment. The I/R injury and protective effects of the dexmedetomidine were evaluated by retinal thickness determined by histological sections, terminal deoxynucleotidyl transferase-mediated biotin-deoxyuridine triphosphate nick-end labeling (TUNEL) and immunohistochemistry of caspases 3. RESULTS: A decrease in the retinal thickness and an increase in the apoptotic cells were found to be statistically significant in I/R and treatment groups when compared with the control group. However, in comparison with the I/R group we realized that the administration of dexmedetomidine reduced the thinning of retinal thickness and also decreased the number of caspases 3 and TUNEL-positive cells. CONCLUSION: Dexmedetomidine is protective against apoptosis in retinal I/R injury in rats.

Recurrent dacryocystitis and lacrimocutaneous fistula caused by a retained Griffiths' collar button stent.

A 42-year-old man presented with a white plastic-like material exposed in the left medial canthal area, with a fistula and purulent discharge. He had undergone endonasal dacryocystorhinostomy 7 years earlier for left eye epiphora; he had persistent postoperative epiphora and recurrent dacryocystitis despite multiple drainage attempts and antibiotics elsewhere. Computed tomography showed bilateral enlarged cystic lacrimal sacs, with a well-defined contoured tunnel-like hole at the center of the left sac. Treatment included excision of the foreign body, which was a Griffiths' collar button nasolacrimal stent, excision of the fistula tract, and revision dacryocystorhinostomy with implantation of bicanalicular silicone stent. He recovered with no further symptoms or complications. This case highlights the importance of follow-up for removal of an implanted Griffiths' stent after dacryocystorhinostomy. Patients with recurrent dacryocystitis may benefit from a detailed history of previous surgery, careful examination, and imaging to evaluate for endogenous and exogenous foreign bodies such as lacrimal sac calculi, and retained lacrimal sac stents.

Obesity and obstructive sleep apnea in patients with keratoconus in a Turkish population.

PURPOSE: The aim of this study was to compare the frequency of occurrence of obesity and high risk of developing obstructive sleep apnea (OSA) in a keratoconus population with that of a control group. METHODS: This prospective, case-controlled multicenter study was performed on patients with keratoconus and age- and gender-matched control subjects. One hundred forty-six patients were included in each group, and the Berlin Questionnaire was used for classifying patients as having a high risk or low risk of developing OSA. The patients' demographic and clinical characteristics were compared with the Mann-Whitney U test for continuous variables and with the χ test for categorical variables. RESULTS: The keratoconus (85 male/61 female) and control (79 male/67 female) groups' median ages were 25 (8-65) and 24 (9-60) years, respectively. Of the 146 patients in each group, 11 (7.5%) patients were determined to be at a high risk of developing OSA in the keratoconus group, and 8 (5.5%) patients were determined to be at a high risk of developing OSA in the control group. There was no significant difference between the groups (P = 0.477). The keratoconus and control groups' median body mass index values were found to be within normal ranges of 23.2 and 23.4, respectively. CONCLUSIONS: In this study, the mean body mass index value of the keratoconus group was determined to be within normal limits. In a Turkish population, the ratio of a high risk of developing OSA was not found to be significantly different between the keratoconus and control groups.