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Alex V Levin

Publications and source records attributed to Alex V Levin.

At least 19 recordsLinked to original sources
PubMed2006

Cornelia de Lange syndrome: parental preferences regarding the provision of medical information.

We surveyed 57 caregivers of children with Cornelia de Lange syndrome (CdLS) using a self-report questionnaire designed to elicit their experiences with receiving information regarding health complications associated with this multisystem disorder. Their most frequent sources of information at the time of diagnosis were a health care provider (86%) and the CdLS Foundation (72%). Although most caregivers (82%) indicated a desire to receive information about all possible CdLS related health complications, on average they recalled receiving information on only 64% of their child's current or future health complications. For two of the top three complications (as ranked by caregivers), information was available to fewer than half of the caregivers at diagnosis. Only 40% of caregivers were satisfied with the amount of information received at diagnosis, while only 45% felt that the information they received was useful. Caregivers indicated a preference for receiving information in written format (59%) or verbally (39%). Our results indicate that caregivers of children with CdLS report a high need for information at diagnosis, regarding their child's actual or potential health complications. Dissatisfaction may result both from a deficiency in information provided, as well as a mismatch between issues mentioned and those that caregivers deem most important. Caregivers may benefit maximally from receiving information in person at the time of diagnosis as well as having an additional written source of information. These findings highlight the importance of complementary sources of information for caregivers and are likely to be relevant for other multisystem disorders.

Adult↗
PubMed2006

Eight previously unidentified mutations found in the OA1 ocular albinism gene.

BACKGROUND: Ocular albinism type 1 (OA1) is an X-linked ocular disorder characterized by a severe reduction in visual acuity, nystagmus, hypopigmentation of the retinal pigmented epithelium, foveal hypoplasia, macromelanosomes in pigmented skin and eye cells, and misrouting of the optical tracts. This disease is primarily caused by mutations in the OA1 gene. METHODS: The ophthalmologic phenotype of the patients and their family members was characterized. We screened for mutations in the OA1 gene by direct sequencing of the nine PCR-amplified exons, and for genomic deletions by PCR-amplification of large DNA fragments. RESULTS: We sequenced the nine exons of the OA1 gene in 72 individuals and found ten different mutations in seven unrelated families and three sporadic cases. The ten mutations include an amino acid substitution and a premature stop codon previously reported by our team, and eight previously unidentified mutations: three amino acid substitutions, a duplication, a deletion, an insertion and two splice-site mutations. The use of a novel Taq polymerase enabled us to amplify large genomic fragments covering the OA1 gene. and to detect very likely six distinct large deletions. Furthermore, we were able to confirm that there was no deletion in twenty one patients where no mutation had been found. CONCLUSION: The identified mutations affect highly conserved amino acids, cause frameshifts or alternative splicing, thus affecting folding of the OA1 G protein coupled receptor, interactions of OA1 with its G protein and/or binding with its ligand.

Albinism, Ocular↗
PubMed2006

Postmortem orbital findings in shaken baby syndrome.

PURPOSE: To compare postmortem orbital findings in pediatric accidental head injury to Shaken Baby Syndrome (SBS). DESIGN: Retrospective study. METHODS SETTING: Institutional. STUDY POPULATION: Thirty-six patients underwent postmortem modified exenteration with sectioning of the orbital contents; 18 victims of SBS and 18 cases of fatal accidental head trauma. OBSERVATION PROCEDURE: In all cases of children who died from accidental head trauma, the orbital tissues were separated to expose the optic nerve sheath. Patients with gross evidence of hemorrhage within the sheath were included. All cases of SBS were included. After accidental head injury, exenteration was performed only if optic nerve sheath hemorrhage was suspected on gross examination. All children younger than 18 years old with head injury as primary cause of death were included. SBS is defined as having at least two of the following: (1) typical abnormal findings on neuroimaging, (2) typical skeletal injury, (3) retinal hemorrhages, (4) history of abusive shaking with or without blunt head trauma, or (5) an inadequate history to explain the observed injuries. MAIN OUTCOME MEASURE: Presence or absence of orbital hemorrhage. RESULTS: Orbital tissue injury is more common in SBS than accidental head trauma without orbital fracture. In addition, optic nerve sheath and optic nerve intradural hemorrhage are also significantly more common in SBS (P < .0001). CONCLUSIONS: Our study reports new evidence of injury to orbital tissues in SBS and supports the concept that these finding are due to unique acceleration-deceleration forces of this type of abusive head injury.

Child, Preschool↗
PubMed2006

The additive effect of topical dorzolamide and systemic acetazolamide in pediatric glaucoma.

BACKGROUND: The effect of adding oral to topical carbonic anhydrase inhibitors in the management of pediatric glaucoma is unknown. METHODS: We undertook a retrospective analysis of children with a diagnosis of glaucoma before the age of 16 years who initially were treated with topical dorzolamide or dorzolamide-timolol combination and then treated with oral acetazolamide. Children who had uveitic glaucoma or who had ocular surgery within 3 months before or during oral acetazolamide therapy were excluded. Various methods of intraocular pressure (IOP) measurement were used in the study. However, in each case, the IOP was measured using the same technique, once at the last visit before the addition of oral acetazolamide and once at the first examination after the addition of oral acetazolamide. RESULTS: Twenty-two patients were included in the study with an age range of 8 months to 15 years. Seventeen children were boys. Oral acetazolamide treatment was via a daily dose (13.3 to 30 mg/kg, mean 22.5 mg/kg), and duration (6 to 31 days, mean 18.1 days). The intraocular pressure (mean +/- SD) before acetazolamide (32.2 +/- 6.5 mm Hg) was significantly different than after acetazolamide (21.8 +/- 6.3 mm Hg) with a mean difference of 10.36 mm Hg (p < 0.0001) and a mean decrease in IOP of 29.6%. CONCLUSIONS: The addition of oral acetazolamide to topical dorzolamide may provide additional reduction in IOP in some children already being treated with topical carbonic anhydrase inhibitors. This possible additive effect has not been observed in adults treated with a combination of topical and systemic carbonic anhydrase inhibitors.

Acetazolamide↗
PubMed2006

Assessment of change of optic nerve head cupping in pediatric glaucoma using the RetCam 120.

PURPOSE: To ascertain the interobserver agreement among various specialists when analyzing images of the optic nerve head taken with the RetCam 120 (Clarity Medical Systems, Inc., Pleasanton, CA) for assessing the progression of optic disk cupping in pediatric glaucoma. METHODS: Five observers compared pairs of RetCam 120 two-dimensional photographs from 64 eyes to identify whether or not changes in the optic disk had occurred. Observers included a pediatric glaucoma specialist, pediatric neurophthalmologist, strabismologist, pediatric ophthalmic imaging specialist, and pediatric ophthalmology fellow. Each was masked to the patient identity and clinical course. For each patient, the observers reviewed the photographs taken prior to therapy and at a minimum of 6 months following initiation of therapy. Interobserver variability was calculated and analysis conducted to identify influential variables. RESULTS: Poor agreement was noted between the observers. No significant association was obtained between agreement level and variables affecting photographic quality: variability of contrast and illumination, exposure and magnification, image clarity, presence of fluorescein on the cornea, and pixelation of the image with poor resolution. Raters noted problems with these image variables in 75.6% of the observations. The Kappa statistic obtained was kappa = 0.29 with overall proportion of agreement of p = 0.69, suggesting a fair agreement but not a moderate agreement. CONCLUSIONS: Comparison of RetCam 120 pediatric optic nerve head photographs, when performed subjectively by observers with different perspectives, and in isolation from clinical information, may not be a reliable indicator of cupping change. In addition, variations in image contrast, luminance, color, and pixelation pose significant challenges to agreement between observers. Comparison of RetCam 120 images should not be considered the sole criterion for monitoring pediatric glaucoma.

Adolescent↗
PubMed2006

Parental understanding of the role of trainees in the ophthalmic care of their children.

OBJECTIVE: To examine parental knowledge and expectations regarding the roles of trainees involved in their child's ophthalmic care. DESIGN: Prospective survey. PARTICIPANTS: Parents of 128 children attending outpatient pediatric ophthalmology clinics at The Hospital for Sick Children in Toronto. METHODS: A questionnaire was given prospectively to parents (and 1 custodial grandparent). They were asked to identify, using a checklist, the roles and responsibilities of medical students, residents, and fellows and to explore their expectations regarding trainee participation using a multiple choice questionnaire. MAIN OUTCOME MEASURES: Parental knowledge and expectations regarding the roles and participation of medical trainees in the ophthalmic care of their children as measured by survey questionnaire. RESULTS: Parental knowledge about the roles of trainees was very limited with one exception: more than 95% knew that medical students are learning to be doctors and most had a good knowledge of the medical student role. More than 76% wanted to be asked specifically if they would allow trainees involved in their child's care. Seventy-five percent were happy to have capable trainees involved, provided that the trainees discuss all decisions with the responsible staff doctor. Parents wanted health care providers to identify themselves by name (77%) and position (86%). Only 3% did not want trainees involved in any part of their child's care. CONCLUSIONS: Although parental knowledge regarding the relative roles of trainees is poor, parents generally are willing to have trainees involved in their child's medical and surgical care, provided they are adequately supervised and that the parent is aware of their participation.

Adolescent↗
PubMed2006

The ocular manifestations of Jacobsen syndrome: a report of four cases and a review of the literature.

PURPOSE: We report ophthalmic manifestations in four Jacobsen syndrome cases, review the literature, and suggest phenotype-genotype correlations. METHODS: Chart review of Ocular Genetics Program patients at The Hospital for Sick Children, Toronto, Canada. RESULTS: Four del11qter cases are presented. Hypertelorism/telecanthus, abnormally slanted palpebral fissures, abnormal retinal findings, nasolacrimal duct obstruction, anomalous extraocular muscles, amblyopia, and microcornea were found. CONCLUSIONS: We report typical findings and novel ocular presentations. Visual prognosis is generally good. Retinal dysplasia and coloboma seem associated with del11q23. ABCG4, NCAM, and Mfrp are candidate genes in this region that theoretically may be disrupted.

ATP Binding Cassette Transporter, Subfamily G↗
PubMed2006

The red reflex.

Eliciting the red reflex is a useful clinical test that can be easily performed in the pediatric emergency room. A direct ophthalmoscope is the only tool needed to perform this test. The test is non-invasive, making it a quick screening tool for even the most apprehensive child. A normal red reflex can rule out intraocular pathology; an abnormal reflex can indicate need for urgent ophthalmologic referral. The differential diagnoses for an absent (or black) reflex; an abnormally sized, shaped or positioned reflex; leukocoria; as well as a non-homogenous reflex are listed.

Child↗
PubMed2006

Utility of molecular testing for related retinal dystrophies.

BACKGROUND: The purpose of this study was to describe our experience with the clinical effects of molecular genetic testing for retinitis pigmentosa (RP) and related retinal dystrophies. METHODS: Chart review of 303 consecutive patients with retinal dystrophies was done when blood was sent for molecular genetic testing between 1993 and 2001. Phenotype information was retrieved for patients with identified mutations. The yield of positive and clinically useful results was assessed. RESULTS: Participants comprised 35 patients with Leber congenital amaurosis, 18 with Usher syndrome, and 250 with isolated RP or other retinal dystrophies. Of these 303 participants, 203 (67%) received positive or negative results of molecular testing for an average of 2.7 genes. Positive results were available in 19 patients after an average time interval of 38+/-22 months (median 33 months, range 1-89 months). No results were received for 84 (28%) patients. In 16 (5%) cases, patients received partial results. Only 19 (6%) patients were found to have sequence changes in RHO, RDS, CRB1, or USH2A, 2 of which were thought to be disease-causing. Only 2 sequence changes were previously documented mutations, but several other novel changes were suspected to be disease-causing mutations also. INTERPRETATION: Molecular testing was helpful only in the minority of cases, largely because of a lack of availability, as well as the complexity of the molecular genetics of RP. Improvements in funding, infrastructure, and molecular knowledge will be necessary to improve the transformation of molecular genetic testing into a clinically relevant bedside tool.

DNA Mutational Analysis↗
PubMed2005

Measurement of intracellular vitamin C levels in human lymphocytes by reverse phase high performance liquid chromatography (HPLC).

OBJECTIVES: Vitamin C plays an active role in many important metabolic processes, such as collagen formation and the prevention of bleeding. Although overt scurvy is now rare, there is evidence that subclinical vitamin C deficiency is still quite common. Serum and plasma vitamin C measurements do not correlate well with tissue levels while lymphocyte vitamin C levels provide the most accurate assessment of the true status of vitamin C stores and are not affected acutely by circadian rhythm or dietary changes. We report a specific and reproducible reverse phase high performance liquid chromatographic method (HPLC) for the quantification of vitamin C in lymphocytes. METHODS: Reverse phase HPLC with a UV detection system was used. National Committee for Clinical Laboratory Standards (NCCLS) guidelines were followed for evaluation. Sample stability testing for lymphocyte vitamin C was performed for a period of 24 h at room temperature and 4 degrees C. Lymphocyte vitamin C levels were measured in 51 children. RESULTS: Lymphocyte vitamin C measurement with HPLC revealed very good analytical sensitivity with a 1.42 microg/10(8) lymphocyte lower limit of detection on repeated testing. An external standard curve was used for quantification, which showed a linear range of 1.25-100 microg/10(8) lymphocyte with a correlation coefficient of 0.989. Precision studies showed an inter-assay repeatability coefficient of variance (CV) between 0.25-9.98% and a within-assay coefficient of variance between 1.2-12.49%. The inter-assay CV for a period of 20 days was less than 10% for concentrations equal to or less than 1.42 microg/10(8) lymphocytes and less than 5.5% for concentrations between 5-100 microg/10(8) lymphocytes. Vitamin C was most stable at 4 degrees C, with a 0.31% decrease after 3 h and 2.35% after 4 h. At room temperature, vitamin C loss was more significant, with losses of 8.44% and 15.6% at 3 and 4 h, respectively, at a concentration of 29.9 microg/10(8) lymphocytes. CONCLUSIONS: The proposed HPLC method offers a reliable and reproducible technique for the quantification of intracellular vitamin C. Lymphocyte samples can be rapidly prepared and represent a more homogeneous tissue sample source for intracellular vitamin C measurement as compared to serum. To ensure stability, lymphocyte lysates should be prepared and stored at or below -20 degrees C within 2 h of blood collection.

Ascorbic Acid↗
PubMed2005

Ophthalmologic findings in the Cornelia de Lange Syndrome.

BACKGROUND: Cornelia de Lange Syndrome (CdLS) is a disorder caused in many patients by a mutation in the NIPBL gene with a dominant pattern of inheritance characterized by mental retardation, prenatal and postnatal growth retardation, upper-limb abnormalities, and characteristic facies. Few data exist concerning the ophthalmic findings in this syndrome. METHODS: One hundred twenty individuals with CdLS underwent ophthalmic examination to ascertain the relative frequencies of oculofacial and ophthalmic abnormalities. RESULTS: We confirmed the frequent findings of synophrys (99%), long lashes (99%), hypertrichosis of the brows (96%), ptosis (44%), epiphora (22%), nasolacrimal duct obstruction (16%), blepharitis (25%), and myopia (58%). In addition, we found peripapillary pigment (83%), and microcornea (21%), which have infrequently been mentioned in the literature. CONCLUSION: Patients with CdLS can have multiple eye problems. Many of these problems can be readily treated, including myopia, blepharitis, nasolacrimal duct obstruction, and ptosis. Early examination is recommended for all children known or suspected to have CdLS.

Adolescent↗
PubMed2005

Endoscopic closure of a cyclodialysis cleft.

Numerous surgical procedures have been proposed to close cyclodialysis clefts. We describe a novel technique, direct cyclopexy under microendoscopic view, in a patient with persistent hypotony despite previous attempts at both surgical repair and cryotherapy for her cyclodialysis cleft.

Child, Preschool↗
PubMed2005

Developing a model system for teaching goniotomy.

PURPOSE: To design a model-system instruction course to prepare trainees for performing goniotomy on patients. DESIGN: Experimental study. PARTICIPANTS: Three pediatric ophthalmology fellows and 1 recent graduate of the fellowship program. METHODS: We piloted 3 model systems: human cadaver eyes with and without Marty the Surgical Simulator (Iatrotech Inc., Del Mar, CA, hereafter referred to as Marty Head) eye supporting system and artificial eyes in Marty Head. For improving intraocular view in cadaver eyes, we used epithelial scrapping, intracameral viscoelastic, and/or intracameral lubricating jelly. Each trainee underwent a training course, including background reading, didactic lecture, and video review followed by goniotomy on model systems with the operating microscope. MAIN OUTCOME MEASURES: Each trainee evaluated each step of the course using modified 5-point Likert scales. Reading material and videos were evaluated for usefulness, readability/quality, and new information obtained. Each model system was evaluated for visibility, ease of setup, surgical feel, and transferability to live surgery. In the end, each trainee was asked to assess the overall course for usefulness. RESULTS: Trainees rated the reading materials and video highly for their usefulness and quality, yet they believed they did not learn substantial amounts of new information. Visibility and ease of setup was best with artificial eyes in the Marty Head model. Human cadaver eyes in the Marty Head provided somewhat less visibility and ease of setup, but the perceived feel and transferability to live surgery was slightly better than with artificial eyes. Cadaver eyes without the Marty Head got the lowest rating in all categories. At the end of the course, all participants felt more confident and ready to perform goniotomy on patients. All recommended this course as part of pediatric ophthalmology fellowship training programs. CONCLUSIONS: This model system instruction course can assist trainees in learning to perform goniotomy while potentially lessening the risks to patients.

Gonioscopy↗
PubMed2005

Computerized corneal topography in a paediatric population with Down syndrome.

PURPOSE: To characterize abnormal corneal topographic changes using corneal computerized videokeratography (CVK) in a paediatric population with Down syndrome, and in their parents. METHODS: Prospective, non-randomized clinical trial. Twenty-one children with Down syndrome (mean age 6.9 years) recruited from The Hospital for Sick Children, 18 of their parents, and a paediatric control group of 60 otherwise well children (mean age 9 years), underwent complete ocular examination and CVK using the EyeSys system. Corneal topographic maps were assessed subjectively, and three objective parameters analysed: central corneal power (CP), difference in central corneal power between the two eyes (DCP), and inferior-superior steepening asymmetry (I-S). RESULTS: Corneal curvature in children with Down syndrome was significantly steeper than in the paediatric control population (CP 46.66 vs 42.60 D, P <0.0001), but changes with age paralleled that of the control population. DCP and I-S values were also significantly different from the control population (P <0.0001). 39% of the parents of children with Down syndrome had at least one abnormal parameter. CONCLUSIONS: This study demonstrates that CVK is a useful tool in the ocular assessment of patients with Down syndrome. The findings suggest that this patient population have abnormalities of corneal shape even in the absence of clinical evidence of keratoconus. A greater than expected incidence of abnormal topographic changes was observed in the parents of these patients.

Adolescent↗
PubMed2005

Eye findings in patients with juvenile dermatomyositis.

OBJECTIVE: Reports of eye involvement in juvenile dermatomyositis (JDM), including significant retinopathy with visual loss, have led some to recommend routine formal ophthalmologic assessments for all patients with JDM at diagnosis. Our objective was to document the frequency and spectrum of eye involvement in patients followed in a single clinic caring for children with JDM. METHODS: A chart review was conducted of formal ophthalmologic consultation notes for patients with JDM followed at the Hospital for Sick Children between 1981 and 2002. RESULTS: Ophthalmologic assessments were found for 82 of 108 patients with JDM. The mean age at diagnosis of JDM was 7.0 years and 68.3% were female. Forty-five patients (55.6%) had abnormal eye examinations. Lid manifestations, found in 37 patients (45.7%), were the most common abnormality. Fourteen patients (17.1%) had corticosteroid-induced cataracts. Two patients had retinal abnormalities; one had a small retinal hemorrhage, the other an incidental chorioretinal scar. Neither had impairment of vision. No patient had uveitis. CONCLUSION: Eyelid and lens abnormalities are common in patients with JDM, while retinopathy is rare. As lid lesions and cataracts are easily detected by non-ophthalmologists, and retinal lesions are rare, we feel that JDM patients without visual symptoms do not require routine formal ophthalmologic assessment for disease manifestations.

Adolescent↗
PubMed2004

Normal computerized tomography of brain in children with shaken baby syndrome.

OBJECTIVE: To characterize the clinical presentation and clinical course of shaken baby syndrome (SBS) with normal cranial computerized tomography (CT) on admission and to suggest further diagnostic procedures in such circumstances. METHODS: Using a worldwide listserv designed to facilitate discussion in the field of child abuse and neglect, we solicited case information for children hospitalized in different medical centers, who were diagnosed with SBS and had a normal CT scan on admission. RESULTS: Nine cases were identified. While all children had an abnormal neurologic examination on admission, eight had a normal CT, and one had "widening of cranial sutures." In four cases, subdural hemorrhage was diagnosed on magnetic resonance imaging (MRI) 3 to 7 days after admission. Five children had bone fractures. The neurological outcome was normal in four of nine cases. Five children had long-term neurologic damage. The diagnosis of SBS was supported by either perpetrator confession, characteristic evolution of brain abnormalities on CT or MRI, inconsistent or absent explanatory history, and/or other social risk factors. CONCLUSION: The diagnosis of SBS can be established even when brain CT is normal on admission. The documentation of retinal hemorrhages is of primary importance in establishing the diagnosis of SBS in these cases.

Brain↗
PubMed2004

Shaken baby syndrome without intracranial hemorrhage on initial computed tomography.

OBJECTIVE: We sought to describe the unique characteristics of children diagnosed with shaken baby syndrome (SBS) despite the absence of intracranial hemorrhage on cranial computerized tomography (CT) on hospital admission. METHODS: Using an international e-mail-based listserv for professionals with an interest in child abuse, we identified and reviewed the charts of children hospitalized in different medical centers who were diagnosed with SBS although CT disclosed no signs of intracranial bleeding. Children with normal imaging were not included. RESULTS: Eight cases were identified. All children had cerebral edema in CT, which was severe on 7/8 cases (88%). All of these children had extensive retinal hemorrhage. The prognosis was poor; 5/8 infants died (63% mortality), and the rest had permanent neurologic damage. CONCLUSION: The diagnosis of SBS can be established even when CT at presentation does not demonstrate intracranial hemorrhage. We hypothesize that rapidly developing cerebral edema may cause increased intracranial pressure and tamponade that prevents the accumulation of intracranial blood. The prognosis in these cases is grave.

Brain Edema↗