Abstract: Advances in intraocular lens (IOL) design have rendered cataract surgery a refractive procedure. Newer IOL types include bifocal, trifocal and extended depth of focus (EDOF) IOLs. Their basic difference nestles in the number of focal points that each lens provides, which in turn leads to different visual outcomes. Familiarity of surgeons with the various characteristics of each lens is of utmost importance for accurate IOL selection to match each patient’s needs. In this review, we aim to compare the clinical outcomes after implantation of multifocal and EDOF IOLs in terms of distance, intermediate and near vision, contrast sensitivity, and reading performance. Finally, we discuss the defocus curve and the optical and photic phenomena associated with each type of IOL.

Abstract: Congenital ptosis is an abnormally low position of the upper eyelid, with respect to the visual axis in the primary gaze. It can be present at birth or manifest itself during the first year of life and can be bilateral or unilateral. Additionally, it may be an isolated finding or part of a constellation of signs of a specific syndrome or systemic associations. Depending on how much it interferes with the visual axis, it may be considered as a functional or a cosmetic condition. In childhood, functional ptosis can lead to deprivation amblyopia and astigmatism and needs to be treated. However, even mild ptosis with normal vision can lead to psychosocial problems and correction is also advised, albeit on a less urgent basis. Although, patching and glasses can be prescribed to treat the amblyopia, the mainstay of management is surgical. There are several types of surgical procedure available depending on the severity and etiology of the droopy eyelid. The first part of this paper will review the different categories of congenital ptosis, including more common associated syndromes. The latter part will briefly cover the different surgical approaches, with emphasis on how to choose the correct condition. In spite of many complex factors inherent to the treatment of congenital ptosis, the overall outcomes are quite satisfactory, and most surgeons feel that ptosis management can be both challenging and rewarding at the same time.

Background: To record the corneal, and anterior chamber depth changes after performing recession versus resection of horizontal recti muscles.

Methods: Consecutive patients who underwent isolated lateral rectus muscle recession or resection February 2014 to January 2015 were prospectively studied. Refractive error (spherical equivalent); K1, K2, and mean k reading, anterior and posterior corneal elevation; and anterior chamber depth were measured (Pentacam) before, 1 month, and 3 months after surgery. Patients who could not maintain reliable fixation and those with a history of eye surgery were excluded. Pre- and postoperative measurements were compared by analysis of variance.

Results: A total of 36 eyes of 23 patients (average age, 16 years) were included. Rectus muscle recession was performed in 24 eyes; and resection was performed in 12 eyes. Statistically significant changes in mean keratometry of recession group only. Central anterior elevation, and central anterior chamber depth were significant when both groups are compared at first month after surgery. Changes became regressive at the end of the third month. Although a significant change of central anterior elevation persisted.

Conclusions: In recession group, the mean K was the only statistically significant variable by the first postoperative month. Comparing the both groups, the anterior corneal elevation, and central anterior chamber depth revealed a significant difference by the end of the first postoperative month. After 3 months, all parameters showed a statistical insignificant difference between the recession and resection groups except the anterior corneal elevation.

Abstract: Anthropometry can analyze the size, weight, and proportion of the human body objectively and quantitatively to supplement the visual assessment. Various non-invasive three-dimensional (3D) anthropometric techniques have been applied to assess soft tissues’ 3D morphology in the clinical practice. Among them, non-invasive stereophotogrammetry and laser scanning techniques are becoming increasingly popular in craniofacial surgery and plastic surgery. They have been applied for craniofacial growth estimation and morphometric investigation, genetic and acquired malformation diagnosis, as well as orthodontic or surgical treatment arrangement and outcome evaluation. However, few studies have been published for assessing the 3D morphology of soft tissues in the periorbital region. This paper reviews the studies involving the application and evaluation of the increasingly popular 3D photogrammetry in the periorbital region. These studies proposed detailed and standardized protocols for three-dimensionally assessing linear, curvilinear, angular, as well as volumetric measurements, and verified its high reliability in the periorbital region (even higher than caliper-derived direct measurements). In the future, reliable and accurate 3D imaging techniques, as well as standardized analyzing protocols, may find applications in following up morphological growth, preoperatively diagnosing and assessing patient periorbital conditions, planning surgical procedures, postoperatively evaluating treatment outcomes of a specific procedure, and comparing the differences in surgical results between various procedures, studies, as well as populations.

Perception is the ability to see, hear, or become aware of external stimuli through the senses. Visual stimuli are electromagnetic waves that interact with the eye and elicit a sensation. Sensations, indeed, imply the detection, resolution, and recognition of objects and images, and their accuracy depends on the integrity of the visual system. In clinical practice, evaluating the integrity of the visual system relies greatly on the assessment of visual acuity, that is to say on the capacity to identify a signal. Visual acuity, indeed, is of utmost importance for diagnosing and monitoring ophthalmological diseases. Visual acuity is a function that detects the presence of a stimulation (a signal) and resolves its detail(s). This is the case of a symbol like “E”: the stimulus is detected, then it is resolved as three horizontal bars and a vertical bar. In fact, within the clinical setting visual acuity is usually measured with alphanumeric symbols and is a three-step process that involves not only detection and resolution, but, due to the semantic content of letters and numbers, their recognition. Along with subjective (psychophysical) procedures, objective methods that do not require the active participation of the observer have been proposed to estimate visual acuity in non-collaborating subjects, malingerers, or toddlers. This paper aims to explain the psychophysical rationale underlying the measurement of visual acuity and revise the most common procedures used for its assessment.

Background: Dyop^® is a dynamic optotype with a rotating and segmented visual stimulus. It can be used for visual acuity and refractive error measurement. The objective of the study was to compare refractive error

measurement using the Dyop^® acuity and LogMAR E charts.

Methods: Fifty subjects aged 18 or above with aided visual acuity better than 6/12 were recruited. Refractive error was measured by subjective refraction methods using the Dyop^® acuity chart and LogMAR E charts and the duration of measurement compared. Thibo’s notation was used to represent the refractive error obtained for analysis.

Results: There was no significant difference in terms of spherical equivalent (M) (P=0.96) or J0 (P=0.78) and J45 (P=0.51) components measured using the Dyop^® acuity and LogMAR E charts. However, subjective refraction measurement was significantly faster using the Dyop® acuity chart (t=4.46, P<0.05), with an average measurement time of 419.90±91.17 versus 452.04±74.71 seconds using the LogMAR E chart.

Conclusions: Accuracy of refractive error measurement using a Dyop^® chart was comparable with use of a LogMAR E chart. The dynamic optotype Dyop^® could be considered as an alternative fixation target to be used in subjective refraction.