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Ocular Motor Cranial Neuropathies
Published in Vivek Lal, A Clinical Approach to Neuro-Ophthalmic Disorders, 2023
Zane Foster, Ashwini Kini, Bayan Al-Othman, Andrew G. Lee
The Hirschberg test can be easily performed to estimate ocular deviation. Normally, when a light is shone into the eye, the light reflex appears almost in the center of the pupil of both eyes. If it is off to the side, and if it is asymmetrical, then this indicates ocular deviation. The amount of deviation from the pupillary axis can be used to estimate the ocular deviation in estimated prism diopters.
Vision and hearing
Published in Ajay Sharma, Helen Cockerill, From Birth to Five Years, 2021
Parents are the first to recognise the majority of squints. The corneal reflex test (Hirschberg test) is performed by shining a light in a person's eyes and observing where the light reflects off the cornea. This light reflex is normally central and symmetrical in both eyes. In divergent squint (exotropia), the light reflection is seen on the medial aspect of the cornea, and in convergent squint (esotropia) on the lateral part of the cornea (see illustrations). Some squints may not be apparent on such examination, and trained clinicians use a cover-uncover test. These tests are not always easy to perform or interpret, and a referral to orthoptists should be made if there is any doubt, parental concern or family history.
Vision and hearing
Published in Ajay Sharma, Helen Cockerill, Nobuo Okawa, From Birth to Five Years, 2014
Ajay Sharma, Helen Cockerill, Nobuo Okawa
The majority of squints are first recognised by parents. The corneal reflex test (Hirschberg test) is performed by shining a light in a person's eyes and observing where the light reflects off the cornea. This light reflex is normally central and symmetrical in both eyes. In divergent squint (exotropia) the light reflection is seen on the medial aspect of the cornea and in convergent squint (esotropia) on the lateral aspect of the cornea (see illustrations). Some squints may not be apparent on such examination and a cover-uncover test can be used by a trained clinician. These tests are not always easy to perform or interpret and a referral to orthoptists should be made if there is any doubt, parental concern or a family history.
Ocular alignment, media, and eyelid disorders in Down syndrome
Published in Strabismus, 2020
Ali Makateb, Hassan Hashemi, Azadeh Farahi, Shiva Mehravaran, Mehdi Khabazkhoob, Soheila Asgari
All patients underwent an eye examination by a general ophthalmologist (AM) and all suspect cases were examined by the strabismologist and pediatric ophthalmologist (AF) before the diagnosis was confirmed. Strabismus was confirmed using the Hirschberg test or simultaneous prism and alternate cover test. In the Hirschberg test, the diagnosis was based on observing any displacement of light reflex from the center of the pupil. Using alternate cover test, the diagnosis was based on observing any vertical phoria, any esophoria more than 8 PD, or exophoria more than 15 PD at near or distance.13 Ptosis was detected by measuring the margin reflex distance 1, and diagnosis was confirmed when the distance from the upper eyelid margin to the corneal light reflex was less than 4 mm.14 Floppy eyelid syndrome was detected by observing an abnormal degree of upper lid laxity during minimal lateral traction.15 For patients who presented with epiphora (tearing), NLDO was suspected, and to confirm the diagnosis, nuclear lacrimal scans were obtained.16 Other pathologies were evaluated using the slit lamp (Haag-Streit, Köniz, Switzerland) or direct observation. The spherical equivalent cycloplegic refraction in the worse eye was used to define refractive errors as myopia (≤ −0.5 D) and hyperopia for (≥ 0.5 D), and pure astigmatism (sphere between −0.5 and +0.5D, and cylinder >0.5D).
Evaluation of a Hirschberg Test-Based Application for Measuring Ocular Alignment and Detecting Strabismus
Published in Current Eye Research, 2021
Stephanie Suzanne S. Garcia, Alvina Pauline D. Santiago, Princess Mae C. Directo
The semi-automated Hirschberg test-based application described in this study demonstrated an easy and simple screening tool with high sensitivity for horizontal strabismus. Vertical strabismus detection capabilities are limited by the lack of available subjects but show potential in measuring deviations in subjects with known vertical strabismus. Optimization of the parameters of conversion and the availability of a larger and more diverse population of subjects can increase the utility of the application for its intended use in the field. Although definitive strabismus evaluation still requires the use of clinical techniques such as the APCT to obtain reliable measurements, remote screening can be achieved with this tool.
The Prevalence of Strabismus and Associated Risk Factors in a Southeastern Region of Brazil
Published in Seminars in Ophthalmology, 2018
Luisa Fioravanti Schaal, Silvana Artioli Schellini, Leonardo Toledo Pesci, Alicia Galindo, Carlos Roberto Padovani, Jose Eduardo Corrente
Strabismus was diagnosed with the Hirschberg test, cover test, and alternate cover test. Individuals were categorized as orthotropic when there were no deviations (orthotropia group) or heterotropic (ET, XT, or associated deviations—a combination of vertical and horizontal strabismus or syndromes) (strabismus group). Risk factors for strabismus were assessed by examining a database of individuals who did not have strabismus (orthotropia group). Between groups, comparisons were performed for the frequency of refractive errors (RE), amblyopia, and presence of anisometropia.