Purpose To analyse corneal power based on a large optical coherence tomography dataset using raytracing, and to evaluate with respect the front apex plane for different definitions of best focus. Methods A OCT (10,218 eyes 8,430 patients) from Casia 2 (Tomey, Japan) was post-processed in MATLAB (MathWorks, USA). Using radius curvature, back surface asphericity, central thickness, pupil size (ap...

PURPOSE To evaluate repeatability and reproducibility of anterior corneal power measurements obtained with a new corneal topographer OphthaTOP (Hummel AG, Germany) and agreement with measurements by a rotating Scheimpflug camera (Pentacam HR, Oculus, Germany) and an automated keratometer (IOLMaster, Carl Zeiss Meditec, Germany). METHODS The right eyes of 79 healthy subjects were prospectively...

PURPOSE To evaluate tear film stability in patients with tear dysfunction and an asymptomatic control group by using the novel, noninvasive Tear Stability Analysis System (TSAS). METHODS In this prospective case-control study, 45 patients with dysfunctional tear syndrome (DTS) were stratified into three groups (1, 2, and 3/4) based on clinical severity, with higher scores indicating more seve...

PURPOSE To evaluate the impact of posterior corneal astigmatism on outcomes with toric intraocular lenses (IOLs). SETTING Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, USA. DESIGN Case series. METHODS Corneal astigmatism was measured using 5 devices before and 3 weeks after cataract surgery. Toric IOL alignment was recorded at surgery and at the slitlamp 3 weeks postop...

BACKGROUND The aim was to profile transient accommodative axial length changes from early adulthood to advanced presbyopia and to determine whether any differences exist between the responses of myopic and emmetropic individuals. METHODS Ocular biometry was measured by the LenStar biometer (Haag-Streit, Switzerland) in response to zero, 3.00 and 4.50 D accommodative stimuli in 35 emmetropes a...

PURPOSE To study the change in ocular refractive components after cycloplegia in children. METHODS Anterior chamber depth, lens thickness, vitreous chamber length, and ocular axial length were measured in 135 Chinese children (270 eyes) before and after cycloplegia. The corneal curvatures of 136 selected eyes were studied before and after cycloplegia with a computerized video keratoscope. R...

Louis Émile Javal was a pioneer in the early history of orthoptics (Figure 1). To anyone knowledgeable about binocular vision, the name Javal conjures up discussions of physiological diplopia, stereoscopes, and fusion training exercises. Javal was a prolific designer of optical devices to use in orthoptic training and ushered in a new era of binocular instrumentation.1–4 Although Wheatstone is ...

OBJECTIVE To evaluate the accuracy of biometry in the post-op phase of cataract surgery. METHODS This study was conducted at Liaquat National Hospital, Karachi, from June 2015 to July 2016, and comprised the audit of patients who underwent cataract surgery during the period. Keratometry was done on Haag-Strait manual keratometer and A-scan was done by applanation contact method on SonoMed mac...

BACKGROUND It is difficult to standardize assessment of dry eye in different clinical settings. Increasingly, tear stability is recognized to be important for the definition and assessment of patients with dry eye. Recently, two commercially available instruments have been made available for objectively measuring noninvasive tear break-up time (NIBUT), as an indicator of tear stability: the Tom...

OBJECTIVE To compare the corneal astigmatism before and after the excision of pterygium and also to determine the correlation of pterygium size with the postoperative corneal astigmatism. STUDY DESIGN Cross-sectional interventional study. PLACE AND DURATION OF STUDY Eye Department, Combined Military Hospital, Abbottabad, from May 2011 to March 2012. METHODOLOGY Thirty patients underwent p...