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Dive into the research topics where Alex V. Levin is active.

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Featured researches published by Alex V. Levin.


American Journal of Ophthalmology | 2002

Correlation between retinal abnormalities and intracranial abnormalities in the shaken baby syndrome.

Yair Morad; Yuri M Kim; Derek Armstrong; Dirk Huyer; Marcellina Mian; Alex V. Levin

PURPOSE To report correlation between retinal and intracranial abnormalities and to evaluate pathogenesis of retinal hemorrhages in the shaken baby syndrome (SBS). DESIGN Observational case series. METHODS Seventy-five children with apparent nonaccidental head trauma consistent with SBS had complete physical examination, complete ophthalmologic examination, neuroimaging by CT or MRI, or both, and skeletal radiographic survey. In this retrospective review, ophthalmoscopic and intracranial abnormalities were correlated. RESULTS The age of patients ranged from 2 to 48 months (mean - SD, 10.6 +/- 10.4 months). Neuroimaging was abnormal in all 75 cases. Findings included subdural hematoma (70 children, 93%), cerebral edema (33 children, 44%), subarachnoid hemorrhage (12 children, 16%), vascular infarction (nine children, 12%), intraparenchymal blood (six children, 8%), parenchymal contusion (six children, 8%), and epidural hemorrhage (one child, 1%). Sixty-four (64/75, 85%) children had retinal abnormalities, mostly (53/64, 82%) confluent multiple hemorrhages that were subretinal, intraretinal, and preretinal in 47/64 (74%) and bilateral in 52/64 (81%). No association was found between anatomic site (left, right, or bilateral) of intracranial and retinal findings (McNemar test kappa = -0.026-0.106) or between any of the intracranial findings mentioned above and the following retinal findings: normal or abnormal retinal examination, multiple (>10) or few retinal hemorrhages (< or =10), symmetric or asymmetric retinal findings, or retinoschisis (kappa = -0.127-0.104). Signs of possible increased intracranial pressure were not correlated with any retinal abnormality (kappa = -0.03-0.073). There was no correlation between evidence of impact trauma to the head and retinal hemorrhages (kappa = 0.058). Total Cranial Trauma Score and Total Retinal Hemorrhage Score, both indicating the severity of injury, were correlated (P =.032). CONCLUSIONS Our study supports previous observations that the severity of retinal and intracranial injury is correlated in SBS. We cannot support the suggestions that in most children with SBS retinal bleeding is caused by sustained elevated intracranial, elevated intrathoracic pressure, direct tracking of blood from the intracranial space, or direct impact trauma. The correlation in severity of both eye and head findings may suggest, however, that retinal abnormalities are the result of mechanical shaking forces.


Nature Genetics | 2003

Heterozygous mutations of the kinesin KIF21A in congenital fibrosis of the extraocular muscles type 1 (CFEOM1).

Koki Yamada; Caroline Andrews; Wai Man Chan; Craig A. McKeown; Adriano Magli; Teresa de Berardinis; Anat Loewenstein; Moshe Lazar; Michael O'Keefe; Robert D. Letson; Arnold London; Mark S. Ruttum; Naomichi Matsumoto; Nakamichi Saito; Lisa Morris; Monte A. Del Monte; Roger H. Johnson; Eiichiro Uyama; Willem A. Houtman; Berendina De Vries; Thomas J. Carlow; Blaine L. Hart; Nicolas Krawiecki; John M. Shoffner; Marlene C. Vogel; James A. Katowitz; Scott M. Goldstein; Alex V. Levin; Emin Cumhur Sener; Banu T. Öztürk

Congenital fibrosis of the extraocular muscles type 1 (CFEOM1; OMIM #135700) is an autosomal dominant strabismus disorder associated with defects of the oculomotor nerve. We show that individuals with CFEOM1 harbor heterozygous missense mutations in a kinesin motor protein encoded by KIF21A. We identified six different mutations in 44 of 45 probands. The primary mutational hotspots are in the stalk domain, highlighting an important new role for KIF21A and its stalk in the formation of the oculomotor axis.


American Journal of Medical Genetics Part A | 2007

Cornelia de Lange syndrome: clinical review, diagnostic and scoring systems, and anticipatory guidance.

Antonie D. Kline; Ian D. Krantz; Annemarie Sommer; Mark A. Kliewer; Laird G. Jackson; David Fitzpatrick; Alex V. Levin; Angelo Selicorni

Cornelia de Lange syndrome (CdLS), also known as Brachmann‐de Lange syndrome, is a well‐described multiple malformation syndrome typically involving proportionate small stature, developmental delay, specific facial features, major malformations (particularly the cardiac, gastrointestinal and musculoskeletal systems), and behavioral abnormalities. There is a broad spectrum of clinical involvement, with increasing recognition of a much milder phenotype than previously recognized. Significant progress has been made in recent years in the clinical and molecular delineation of CdLS, necessitating a revision of the diagnostic criteria, more inclusive of the milder cases. In addition, a scoring system of severity has been found to correlate with specific brain changes. Thus, a clinical overview and recommendations for anticipatory guidance are timely in aiding caretakers and professionals to individualize care decisions and maximize developmental potential for individuals with CdLS. These guidelines are derived from consensus based on collective experience of over 500 patients with CdLS, observations of the natural history in children, adolescents, and adults, a review of the literature, and contacts with national support organizations in North America and Europe.


Pediatrics | 2010

Retinal Hemorrhage in Abusive Head Trauma

Alex V. Levin

Retinal hemorrhage is a cardinal manifestation of abusive head trauma. Over the 30 years since the recognition of this association, multiple streams of research, including clinical, postmortem, animal, mechanical, and finite element studies, have created a robust understanding of the clinical features, diagnostic importance, differential diagnosis, and pathophysiology of this finding. The importance of describing the hemorrhages adequately is paramount in ensuring accurate and complete differential diagnosis. Challenges remain in developing models that adequately replicate the forces required to cause retinal hemorrhage in children. Although questions, such as the effect of increased intracranial pressure, hypoxia, and impact, are still raised (particularly in court), clinicians can confidently rely on a large and solid evidence base when assessing the implications of retinal hemorrhage in children with concern of possible child abuse.


American Journal of Ophthalmology | 2003

The Ahmed drainage implant in the treatment of pediatric glaucoma

Yair Morad; Craig E Donaldson; Yuri M Kim; Mohamed Abdolell; Alex V. Levin

PURPOSE To report the safety and efficacy of Ahmed Glaucoma Valve (New World Medical, Inc., Rancho Cucamonga, California, USA) implantation for the management of pediatric glaucoma in the early and intermediate follow-up period. DESIGN Consecutive interventional case series. METHOD A retrospective chart review was conducted on 60 eyes (44 patients, age range at surgery 1.5 months to 16 years, average 6 +/- 4.9 years), with pediatric glaucoma that underwent Ahmed Glaucoma Valve implantation for medically uncontrolled intraocular pressure (IOP) between the years 1995 and 2000. Outcome measures were control of IOP below 21 mm Hg, the need for antiglaucoma medications after surgery, and loss of 2 or more lines of Snellen acuity. Complications were monitored. RESULTS The postoperative follow-up period for each eye averaged 24.3 +/- 16 months (range, 3 to 60 months). At last follow-up, IOP was controlled in 44 eyes (73%), 11 of which did not need antiglaucoma therapy. Kaplan-Meier life-table analysis showed probability of success with or without medications of 93% (95% confidence interval [CI], 86%-100%), 86% (95% CI, 77%-96%), 71% (95% CI, 59%-87%), and 45% (95% CI, 28%-80%) after 12, 24, 36, and 48 months of follow-up. Average IOP decreased from 32.8 +/- 6.2 before surgery to 16.6 +/- 8.0 postoperatively (P <.0001). The average number of medications used decreased from 4.4 +/- 1.97 to 2.0 +/- 2.0 (P <.0001). Kaplan-Meier survival analysis did not reveal any difference in survival profiles related to specific diagnosis of glaucoma, age (above or below 18 months), or prior surgery. Complications occurred in 30 eyes (50%). Although most resolved or were treated successfully, four patients had severe visual loss during the follow-up. Uveitis was a significant risk factor for tube exposure (Fisher exact test, P =.006). CONCLUSIONS Ahmed Glaucoma Valve implantation is an effective treatment for pediatric glaucoma, although patients frequently require antiglaucoma medications. However, a high rate of potentially sight-threatening postoperative complications warrants ongoing close follow-up.


Ophthalmology | 1992

Retinal findings after head trauma in infants and young children.

Yvonne M. Buys; Alex V. Levin; Robert W. Enzenauer; James E. Elder; Mary A. Letourneau; Robin P. Humphreys; Marcellina Mian; J. Donald Morin

BACKGROUND Many authorities believe that the finding of retinal hemorrhages in a child younger than 3 years of age with a history of head trauma, in the absence of an obvious cause for the injury, is pathognomonic of child abuse. To date, no studies have examined the prospective retinal examination of children who have had head trauma. The authors undertook such a study because the presence of retinal hemorrhage from any head trauma in children may have medicolegal diagnostic significance in differentiating accidental from nonaccidental trauma. METHODS Seventy-nine children younger than 3 years of age, each of whom experienced head injury, underwent an ophthalmologic assessment, which included a dilated funduscopic examination. RESULTS Seventy-five children sustained accidental head injuries and had normal funduscopic examinations. Three children had nonaccidental head injuries and all were found to have varying degrees of retinal hemorrhages. One child, with a normal fundus examination, had injuries that were of indeterminate cause. CONCLUSION The finding of retinal hemorrhages in a child with a head injury suggests a nonaccidental cause.


Journal of Aapos | 1999

The epidemiology of pediatric glaucoma: The Toronto experience

Robert H. Taylor; John R. Ainsworth; Anthony R. Evans; Alex V. Levin

BACKGROUND This study was conceived to provide an insight into the spectrum of glaucoma in the pediatric population. We also set out to compare the success of disease control and the prognosis for vision within the different diagnostic subgroups. This is the largest single population of children with glaucoma that has been so described and compared. METHODS The charts of children who were first seen between birth and age 16 years and who attended the Hospital for Sick Children with any form of glaucoma between January 1974 and January 1995 were reviewed and entered into the study. RESULTS Data are presented for 306 children. Congenital glaucoma was the most common subtype, accounting for 38%. Patients with congenital glaucoma were young, had surgery, and had more operations than any other group except those with aniridia. Goniotomy offered a cure in 47.8% of the patients. A bimodal distribution reflected their visual performance. Patients with aphakic glaucoma, the next most prevalent group (20%), presented at an older age (4.5 years). Surgical intervention was performed in 50% of these children. Nearly all patients with Sturge-Weber syndrome (80%) had surgery. The following glaucoma groups were associated with a poor visual outcome: aniridia, anterior segment developmental anomalies involving the cornea, uveitis with glaucoma other than steroid induced, retinopathy of prematurity, and persistent hyperplastic primary vitreous. Steroid-induced glaucoma and anterior segment dysgenesis, excluding Peters anomaly, had uniformly good outcomes. CONCLUSION The ability to control glaucoma in childhood and visual prognosis is highly variable. Particular diagnostic categories do consistently well and some do poorly.


Ophthalmology | 2002

Retinal findings in children with intracranial hemorrhage

Susan Schloff; Paul B. Mullaney; Derek Armstrong; Emmanuel Simantirakis; Robin P. Humphreys; John S. Myseros; J. Raymond Buncic; Alex V. Levin

PURPOSE To identify the incidence of Tersons syndrome in children. DESIGN Prospective, observational case series. PARTICIPANTS Fifty-seven consecutive children with known intracranial hemorrhage from nonabuse causes. METHODS Dilated fundus examination to detect intraretinal hemorrhages or other abnormalities. MAIN OUTCOME MEASURES Presence or absence of intraretinal hemorrhages or other abnormalities. RESULTS Fifty-five patients (96%) had no evidence of intraretinal or vitreous hemorrhage. Two patients had abnormal retinal examinations. One patient had a single dot hemorrhage associated with presumed infectious white retinal lesions. The second patient had three flame and two deeper dot intraretinal hemorrhages after a motor vehicle accident (1.5% incidence of retinal hemorrhage). CONCLUSIONS Retinal hemorrhage is uncommon in children with intracranial hemorrhage not resulting from shaken baby syndrome. The maximal incidence of intraretinal hemorrhage in children with nonabuse intracranial hemorrhage is 8%.


Journal of Aapos | 2008

Course, complications, and outcome of juvenile arthritis–related uveitis

Kourosh Sabri; Rotraud K. Saurenmann; Earl D. Silverman; Alex V. Levin

PURPOSE To describe the clinical features of uveitis in patients with juvenile idiopathic arthritis (JIA). METHODS Retrospective chart review of a subset of 1,081 consecutive JIA patients who were younger than 18 years of age and had uveitis, with a minimum of 1-year follow-up at a single center. RESULTS One hundred forty-two patients (13.1%) developed uveitis after a mean follow-up of 6.3 years (range, 0.10-23.2). Uveitis types were chronic anterior (97/142, 68.3%), acute anterior (23/142, 16.2%), recurrent anterior (17/142, 12%), and panuveitis (5/142, 3.5%). Uveitic complications were observed in 37.3% of cases (53/142) and 32.5% of eyes (74/228). When we compared uveitic eyes with complications to uveitic eyes without complications, we found the following significant differences: time interval from diagnosis of JIA to diagnosis of uveitis was shorter (mean, 1.3 years vs. 2.2 years; p = 0.003) and use of oral prednisone was greater (59.1% vs 15.6%; p < 0.0001) in the eyes with complications. Twenty-one children (21/142, 14.8%) with uveitis underwent a total of 62 ocular surgeries. Good visual acuity (20/40 or better) was found in 90.8% of eyes (159/175) and in both eyes of 87% of cases (94/108), impaired visual acuity in 6 eyes of 4 cases (6/175, 3.4%), and blindness in 10 eyes of 10 cases (10/175, 5.7%). Only 2 patients had reduced visual acuity in both eyes. Surgery was the single most important risk factor for reduced visual acuity at the last follow-up (p = 0.0086). CONCLUSIONS Most uveitic eyes with JIA achieved good visual outcome despite uveitic complications.


Documenta Ophthalmologica | 2001

Values of electroretinogram responses according to axial length

Carol Westall; Harjinder S. Dhaliwal; Carole M. Panton; Dayle A. Sigesmund; Alex V. Levin; Ken K. Nischal; Elise Héon

Accurate interpretation of electroretinograms (ERGs) requires knowledge of effects of axial myopia on ERG responses. Our purpose was to derive expected changes of ERG responses according to axial length, to stimulus conditions that conform to the International Society for Clinical Electrophysiology of Vision (ISCEV) Standard for Electroretinography. ERGs from 60 subjects were recorded. The subjects were assigned to one of three groups according to the level of myopia. Thirty-three subjects had high myopia (−6.00 D to −14.50 D; mean age, 31 years), eight had mild myopia (−3.00 D to −5.00; mean age, 28 years), and 19 had a small refractive error (+0.75 D to −2.75 D; mean age, 27 years). No subjects had myopic retinopathy. Stimulus-response curves were fitted to dark-adapted b-wave amplitudes and maximum amplitude and semi-saturation constants derived. Axial lengths, measured with A scan ultrasound, ranged from 22.2 mm to 30.0 mm. Analysis of variance and post hoc t-tests revealed significant difference between subjects with high myopia and subjects with small refractive error for ERG amplitude data. There were no significant differences between the three groups for implicit times, the ratio of b- to a-wave and semi-saturation constant. There is linear reduction in the logarithmic transform of ERG amplitude with increasing axial length, related more to axial length than refractive error. We provide relative slope and intercept values, allowing labs to derive expected ERG amplitudes according to axial length. These derivations are valid for persons with no retinopathy.

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Annemarie Sommer

Nationwide Children's Hospital

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Antonie D. Kline

Greater Baltimore Medical Center

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Ian D. Krantz

Children's Hospital of Philadelphia

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Mark A. Kliewer

University of Wisconsin-Madison

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