Comparison of Contrast Sensitivity and Central Corneal Thickness in Primary Open Angle Glaucoma Suspects and Visually Normal Participants

@#Introduction: Glaucoma causes a reduction of contrast sensitivity (CS) while thinner central corneal thickness is (CCT) associated with the risk of glaucoma. Thus, in glaucoma suspect patients, CS and CCT measurements may better evaluate and monitor the disease. The purpose of this study was to compare CS and CCT between a Primary Open Angle Glaucoma (POAG) suspect group and a normal group of similar age. Methods: CS was measured with the Pelli-Robson CS chart, while CCT was measured with a hand-held pachymeter. In total, 115 glaucoma suspects and 102 normal participants were included. Results: There was a significant effect of the clinical condition on CS [F(1,209)=5.409, p=0.02]. The effect of age on CS was also significant [F(3,209)=20.419, p<0.001]. The interaction between age and clinical condition was not statistically significant [F(3,209)=0.815, p=0.49]. CS of POAG suspects was significantly lower than that of the normal group for the younger age groups (40 to 59 years old) but not for the older age groups (50 to 80 years old). There was no significant effect of clinical condition on CCT [F(3,209)=0.754, p=0.39]. However, there was a significant effect of age on CCT [F(3,209)=3.789, p=0.01]. Conclusion: Contrast sensitivity measurement is potentially useful to be integrated with routine investigations for POAG suspect patients, especially those who are younger than 60 years old. Measurements of central corneal thickness alone may not be able to differentiate between POAG suspects and visually normal individuals.

Appointment Compliance by Patients at UKM Optometry Clinic / Jurnal Sains Kesihatan Malaysia

@#Patient’s appointment compliance refers to the willingness and ability of a patient to attend to their scheduled clinicalappointment. Failure to do so have various consequences, especially so for a teaching clinic such as the OptometryClinic, Universiti Kebangsaan Malaysia (UKM). The percentage of appoinment compliance at the Optometry Clinic wasanalysed from September to December 2015. Compliance rate was categorised based on clinic type and session, and onpatient’s gender and ethnicity. Attendance compliance was around 60% for the Primary Care Clinic. It increased to 70%for patients with vision problems who where referred to specialty clinics i.e. Low Vision and Paediatric Clinics. Clinicday and session did not influence compliance significanly (p > 0.05). Patient’s gender and ethnicity did not influencecompliance significantly as well but those of Indian ethnicity consistently showed the lowest appointment compliancerates. A protocol should be developed to increase the rate of patients’ appoinment compliance. This would then maximiseproductivity of students and clinic staff and optimise the clinic’s resources. The cost of each clinical session could beinformed to the patients, even when the cost is not borne by them.

Effects of Monocular Blur on Clinical Measurements of Stereopsis and Binocular Contrast Sensitivity / Jurnal Sains Kesihatan Malaysia

Visual conditions such as anisometropia, monovision and monocular undercorrection affect the combination of visual input from both eyes. This study investigated the effects of monocular blur, in binocularly normal participants, on stereoacuity and binocular contrast sensitivity. Fifteen young adults (age range between 19 and 23 years old) with normal visual acuity and binocular vision participated in this study. Stereopsis was measured using the TNO test with a series of positive spherical lenses placed before the dominant eye. The procedure was repeated using the Titmus Stereotest on five participants as a control experiment. Monocular and binocular contrast sensitivities were also measured using the Pelli-Robson Contrast Sensitivity Chart. Blur was induced monocularly with a series of positive spherical lenses placed before the dominant eye and binocular contrast sensitivity was re-measured. Stereopsis scores decreased significantly when monocular blur was imposed. Across blur levels, absolute stereopsis scores measured with TNO test were worse than those measured with Titmus stereotest (all p < 0.05). However, the ratio of scores obtained without blur and under monocular blur appeared to be similar for both tests. Stereopsis without blur was between 6.82× to 8× better than that obtained with the highest level of imposed monocular blur. Binocular contrast sensitivity score decreased significantly with increasing level of monocular blur (p < 0.01). Binocular contrast sensitivity score without blur was 1.62× better than that obtained under binocular viewing with highest level of imposed blur. Stereopsis tests are more sensitive than measurements of binocular contrast sensitivity as an indicator of interocular acuity discrepancies which could occur in anisometropic or monovision patients. However, the choice of stereopsis test is crucial, as the TNO test appears to be more sensitive to monocular blur than the Titmus stereostest.