Comparison of Immediate Effects on Usage of Dual Polymer Artificial Tears on Changes in Tear Film Characteristics

@#Introduction: This study aimed to evaluate the short-term efficacy of two comparable formulation of dual-polymer artificial tears: Systane Hydration preservative (SH) and non-preservative (SHUD) in 60 minutes observation period compared to normal saline. Methods: Fifty participants involved in this prospective, double-masked randomised study. Viscosity and pH of artificial tears were evaluated using rheometer and digital pH-meter prior to tear film assessment. Tear break-up time (TBUT) and tear meniscus height (TMH) were measured at baseline, 5, 15 and 60 minutes after instillation. Tear ferning pattern (TFP) were compared between baseline and 60 minutes after instillation. One-way analysis of variance (ANOVA) and Independent T-test were used to evaluate the effects of SH and SHUD after instillation and comparison between each specific time-interval respectively. P-value of 0.05 was set as the level of significance. Results: The viscosity of SH and SHUD was 26.7cP and 32.73cP re-spectively with pH of 7.85 (SH) and 7.74 (SHUD). Both artificial tears showed significant increment in TBUT between baseline and 15 minutes (SH:5.82±1.063, p=0.01; SHUD:6.02±0.979, p<0.001), and 60 minutes (SH:6.22±0.616, p<0.001; SHUD:6.34±0.658, p<0.001). SHUD demonstrated significant increment in TMH at every measurement taken (0.1996±0.02449, p<0.001 at 5min, 0.2038±0.02276, p<0.001 at 15min and 0.2068±0.02094, p<0.001 at 60min). Likewise, in SH group, significant increment in TMH at 15 minutes (0.1994±0.02325, p<0.001) and 60 minutes (0.2012±0.02379, p<0.001) were noted. Both groups revealed improvement in TFP (both, p<0.001) at 60 minutes. No significant im-provement was noted in control group. Conclusion: Improvement in TMH was prominently faster in SHUD than SH, although both TBUT and TFP revealed comparable tears quality between both artificial tears.

Intraocular Pressure: the Effect of Short-term Fasting and Its Association With Fluid and Fat Status

@#Introduction: Short-term fasting may influence intraocular pressure (IOP) due to alteration of fluid (total body water; TBW, and water intake) and fat (total body fat; TBF). This study aimed: i) to compare IOP values within and between, fasting and non-fasting periods; and ii) to assess the association between IOP and, TBW and TBF. Methods: Thirty healthy participants aged 21.8±1.1 years were assessed on two different periods (fasting vs. non-fasting). During each period, the IOP, TBW and TBF values were assessed for four times (morning, afternoon, evening, late-evening). The IOP was measured using AccuPen® tonopen, while TBW and TBF were assessed by using a Tanita body composition analyser. Results: During fasting, the IOP value in the afternoon (14.53±2.33 mmHg) was significantly higher than in the evening (12.43±2.73 mmHg, p=0.009) and late-evening (12.60±2.44 mmHg, p=0.003). No significant difference in IOP was observed during non-fasting period. The mean of IOP in the evening was significantly lower during fasting compared to non-fasting (12.43±2.73 mmHg vs 13.75±2.53 mmHg, p=0.044). The IOP and TBW were negatively correlated (r=-0.268; p=0.011) during non-fasting and showed no association during fasting period. There was no significant correlation between IOP and TBF during both fasting and non-fasting periods. Conclusion: IOP reduction during short-term fasting, together with the no association with TBF and TBW suggested that IOP is an independent factor that reduces during fasting in healthy population.

Corneo-pterygium total area measurements utilising image analysis method / Mediciones del área total de pterigium corneal utilizando un método de análisis de imagen

PURPOSE: To describe an objective method to accurately quantify corneo-pterygium total area (CPTA) by utilising image analysis method and to evaluate its association with corneal astigmatism (CA). METHODS: 120 primary pterygium participants were selected from patients who visited an ophthalmology clinic. We adopted image analysis software in calculating the size of invading pterygium to the cornea. The marking of the calculated area was done manually, and the total area size was measured in pixel. The computed area is defined as the area from the apex of pterygium to the limbal-corneal border. Then, from the pixel, it was transformed into a percentage (%), which represents the CPTA relative to the entire corneal surface area. Intra- and inter-observer reliability testing were performed by repeating the tracing process twice with a different sequence of images at least one (1) month apart. Intraclass correlation (ICC) and scatter plot were used to describe the reliability of measurement. RESULTS: The overall mean (N = 120) of CPTA was 45.26 ± 13.51% (CI: 42.38-48.36). Reliability for region of interest (ROI) demarcation of CPTA were excellent with intra and inter-agreement of 0.995 (95% CI, 0.994-0.998; P < 0.001) and 0.994 (95% CI, 0.992-0.997; P < 0.001) respectively. The new method was positively associated with corneal astigmatism (P < 0.01). This method was able to predict 37% of the variance in CA compared to 21% using standard method. CONCLUSIONS: Image analysis method is useful, reliable and practical in the clinical setting to objectively quantify actual pterygium size, shapes and its effects on the anterior corneal curvature

OBJETIVO: Describir un método objetivo para cuantificar con precisión el área total corneal invadida por pterigium (CPTA) utilizando un método de análisis de imagen evaluando su asociación con el astigmatismo de la córnea (AC). MÉTODOS: Se seleccionaron 120 participantes con pterigium primario de entre los pacientes que acudieron a la clínica oftalmológica. Utilizamos un software de análisis de imagen para calcular el tamaño del pterigión invasivo hacia la córnea. La marcación del área calculada se realizó manualmente, midiéndose en píxeles el tamaño del área total. El área computada se define como el área desde el ápex del pterigium al borde del limbo corneal. A continuación, a partir del análisis de pixels, se transformó en un porcentaje (%), que representa el CPTA relativo al área total de la superficie de la córnea. Se realizaron pruebas de fiabilidad Intra- e inter-observador mediante un proceso, de doble repetición, con una secuencia de imágenes diferente, con separación de un (1) mes como mínimo. Se utilizaron la correlación intra-clase (ICC) y el gráfico de dispersión para describir la fiabilidad de las mediciones. RESULTADOS: La media global (N = 120) de CPTA fue 45,26 ± 13,51% (IC: 42,38-48,36). La fiabilidad para la demarcación de la región de interés (ROI) de CPTA fue excelente con intra e inter-acuerdo de 0,995 (95% IC, 0,994-0,998; P < 0,001) y 0,994 (95% IC, 0,992-0,997; P < 0,001) respectivamente. El nuevo método se asoció positivamente al astigmatismo de la córnea (p < 0,01). Este método fue capaz de predecir el 37% de la varianza de AC, en comparación con el 21% utilizando el método estándar. CONCLUSIONES: El método de análisis de imagen descrito es útil, fiable y práctico en el entorno clínico, para cuantificar objetivamente el tamaño real del pterigium, así como sus formas y efectos sobre la curvatura anterior de la córnea

Corneo-pterygium total area measurements utilising image analysis method.

PURPOSE: To describe an objective method to accurately quantify corneo-pterygium total area (CPTA) by utilising image analysis method and to evaluate its association with corneal astigmatism (CA). METHODS: 120 primary pterygium participants were selected from patients who visited an ophthalmology clinic. We adopted image analysis software in calculating the size of invading pterygium to the cornea. The marking of the calculated area was done manually, and the total area size was measured in pixel. The computed area is defined as the area from the apex of pterygium to the limbal-corneal border. Then, from the pixel, it was transformed into a percentage (%), which represents the CPTA relative to the entire corneal surface area. Intra- and inter-observer reliability testing were performed by repeating the tracing process twice with a different sequence of images at least one (1) month apart. Intraclass correlation (ICC) and scatter plot were used to describe the reliability of measurement. RESULTS: The overall mean (N=120) of CPTA was 45.26±13.51% (CI: 42.38-48.36). Reliability for region of interest (ROI) demarcation of CPTA were excellent with intra and inter-agreement of 0.995 (95% CI, 0.994-0.998; P<0.001) and 0.994 (95% CI, 0.992-0.997; P<0.001) respectively. The new method was positively associated with corneal astigmatism (P<0.01). This method was able to predict 37% of the variance in CA compared to 21% using standard method. CONCLUSIONS: Image analysis method is useful, reliable and practical in the clinical setting to objectively quantify actual pterygium size, shapes and its effects on the anterior corneal curvature.