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Dive into the research topics where Nadav Belfair is active.

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Featured researches published by Nadav Belfair.


American Journal of Human Genetics | 2011

High Myopia Caused by a Mutation in LEPREL1, Encoding Prolyl 3-Hydroxylase 2

Shikma Mordechai; Libe Gradstein; Annika Pasanen; Rivka Ofir; Khalil El Amour; Jaime Levy; Nadav Belfair; Tova Lifshitz; Sara Joshua; Ginat Narkis; Khalil Elbedour; Johanna Myllyharju; Ohad S. Birk

Autosomal-recessive high-grade axial myopia was diagnosed in Bedouin Israeli consanguineous kindred. Some affected individuals also had variable expressivity of early-onset cataracts, peripheral vitreo-retinal degeneration, and secondary sight loss due to severe retinal detachments. Through genome-wide linkage analysis, the disease-associated gene was mapped to ∼1.7 Mb on chromosome 3q28 (the maximum LOD score was 11.5 at θ = 0 for marker D3S1314). Sequencing of the entire coding regions and intron-exon boundaries of the six genes within the defined locus identified a single mutation (c.1523G>T) in exon 10 of LEPREL1, encoding prolyl 3-hydroxylase 2 (P3H2), a 2-oxoglutarate-dependent dioxygenase that hydroxylates collagens. The mutation affects a glycine that is conserved within P3H isozymes. Analysis of wild-type and p.Gly508Val (c.1523G>T) mutant recombinant P3H2 polypeptides expressed in insect cells showed that the mutation led to complete inactivation of P3H2.


Clinical and Experimental Ophthalmology | 2008

Prognostic factors in posterior open globe injuries (zone-III injuries)

Boris Knyazer; Jaime Levy; Shirley Rosen; Nadav Belfair; Itamar Klemperer; Tova Lifshitz

Purpose:  The aim of this study is to describe and identify clinical characteristics, prognostic factors and visual outcome in a group of patients with posterior open globe injuries (zone III injury).


Canadian Journal of Ophthalmology-journal Canadien D Ophtalmologie | 2005

Central serous chorioretinopathy in patients receiving systemic corticosteroid therapy.

Jaime Levy; Mira Marcus; Nadav Belfair; Itamar Klemperer; Tova Lifshitz

Central serous chorioretinopathy (CSCR) is characterized by a serous detachment of the neurosensory retina or the retinal pigment epithelium (RPE), or both, at the posterior pole. The etiology and pathogenesis of this disorder are still unknown. Several hypotheses have been proposed, including increased permeability of the choriocapillaris, defects in Bruch’s membrane and a defect in the diffusion-barrier function of the RPE. Among the possible risk factors for CSCR, corticosteroids (endogenous or exogenous) have been implicated in the pathogenesis of the disease.1–8 We present 2 cases in which CSCR developed in patients given oral steroid therapy and resolved after treatment was stopped. The previously reported cases and possible effects of corticosteroids on CSCR pathogenesis are discussed.


Nephron | 2002

High Postdialysis Urea Rebound Can Predict Intradialytic Increase in Intraocular Pressure in Dialysis Patients with Lowered Intradialytic Hemoconcentration

David Tovbin; Nadav Belfair; Sorin Shapira; Gideon Rosenthal; Michel Friger; Leonid Feldman; Tova Lifshitz; Zvi Tessler

Background: Intradialytic (ID) decrease in intraocular pressure (IOP) parallel to ultrafiltration-induced hemoconcentration has been recently reported. However, exacerbation of glaucoma in hemodialysis (HD) patients during HD sessions is occasionally observed. Postdialysis urea rebound (PDUR) is induced by the lag in urea removal from the cells to urea removal from the extracellular fluid, which when increased can result in ID drag of water to intracellular compartment. It is our hypothesis that similar lag in urea removal from ocular compartments may also be reflected by PDUR, and may induce drag of water into ocular compartments counteracting the effect of hemoconcentration. Our assumption was, therefore, that PDUR might predict ID increase in IOP. Methods: IOP, serum urea and hematocrit levels were measured at the start, end and 1 h postdialysis, in 19 chronic HD patients with normal IOP. Results: PDUR was positively correlated with mean (both eyes) ID changes in IOP (MIDIOP) (r = 0.5, p = 0.03) and % MIDIOP (r = 0.55, p = 0.02). ID increase in IOP was observed only in the 7 patients with relatively higher PDUR (≧9 mg%), who had also a relatively lower % ID change in Hct (<8%). MIDIOP was negatively correlated with % ID changes in Hct (r = –0.65, p = 0.03) in the 12 patients with PDUR ≧9 mg, and positively correlated with PDUR (r = 0.57, p = 0.03) in the 14 patients with % ID change in Hct <8%. Conclusion: High PDUR may predict susceptibility to ID increase in IOP in patients with lowered ID hemoconcentration.


International Ophthalmology | 2004

Rapid Spontaneous Resolution of Vitreomacular Traction Syndrome Documented by Optical Coherence Tomography

Jaime Levy; Itamar Klemperer; Nadav Belfair; Alexander Rogozin; Tova Lifshitz

A 48-year-old woman presented with a 2-week history of metamorphopsia and reduced vision in her left eye. Visual acuity was 20/30 OS. Slit lamp biomicroscopy fundus evaluation revealed a dull foveal reflex. Optical coherence tomography (OCT) showed attachment of the posterior hyaloid to the macula and significant macular elevation. One month after presentation, visual complaints disappeared. OCT revealed complete posterior vitreous detachment and normal foveal thickness. Although rare, rapid spontaneous resolution of vitreomacular traction syndrome can occur. OCT is a helpful diagnostic tool for following these patients.


Canadian Journal of Ophthalmology-journal Canadien D Ophtalmologie | 2005

Removal of giant vernal papillae by CO2 laser

Nadav Belfair; Tova Monos; Jaime Levy; Haim Mnitentag; Tova Lifshitz

BACKGROUND We report our experience in removing giant papillae in cases with severe vernal keratoconjunctivitis using CO2 laser. METHODS Five cases with conjunctival giant papillae due to severe vernal keratoconjunctivitis were treated with CO2 laser. All cases were resistant to conventional treatment. In 4 eyes, there was also an associated corneal shield ulcer. RESULTS In all 5 cases the procedure was uneventful. Retreatment was performed in only 2 cases because of recurrence of the papillae. No intra- or postoperative complications were observed. INTERPRETATION CO2 laser seems to be a safe method for removing conjunctival giant papillae in cases with severe vernal keratoconjunctivitis. It is also a repeatable method that enables a rapid conjunctival and corneal recovery.


American Journal of Perinatology | 2016

Preeclampsia and Future Risk for Maternal Ophthalmic Complications

Ofer Beharier; Ehud Davidson; Ruslan Sergienko; Irit Szaingurten-Solodkin; Roy Kessous; Ron Charach; Nadav Belfair; Eyal Sheiner

Objective To investigate whether patients with a history of preeclampsia have an increased risk of long-term ophthalmic complications. Study Design A population-based study comparing the incidence of long-term maternal ophthalmic complications in a cohort of women with and without a history of preeclampsia. Results During the study period, a total of 103,183 deliveries met the inclusion criteria; 8.1% (n = 8,324) occurred in patients with a diagnosis of preeclampsia during at least one of their pregnancies. Patients with preeclampsia had a significantly higher incidence of long-term ophthalmic morbidity such as diabetic retinopathy and retinal detachment. In addition, a positive linear correlation was found between the severity of preeclampsia and the prevalence of future ophthalmic morbidities (0.3 vs. 0.5 vs. 2.2%, respectively). Kaplan-Meier survival curve indicated that women with preeclampsia had higher rates of total ophthalmic morbidity (0.2 vs. 0.4%, for no preeclampsia and with preeclampsia, respectively; odds ratio = 2.06, 95% confidence interval: 1.42-2.99; p < 0.001). In a Cox proportional hazards model, adjusted for confounders, a history of preeclampsia remained independently associated with ophthalmic complications. Conclusion Preeclampsia is an independent risk factor for long-term maternal ophthalmic morbidity, specifically diabetic retinopathy and retinal detachment. This risk is more substantial depending on the severity of the disease.


BioMed Research International | 2014

The Outcomes of Primary Scleral Buckling during Repair of Posterior Segment Open-Globe Injuries

Daniel Cohen; Jaime Levy; Tova Lifshitz; Nadav Belfair; Itamar Klemperer; Noam Yanculovich; Boris Knyazer

Objective. To compare visual outcomes of eyes which underwent primary scleral buckling (PSB) treatment during posterior segment open-globe injury (OGI) repair with eyes not treated with PSB. Methods. We retrospectively reviewed 38 eyes which underwent a posterior segment OGI repair with no preoperative evidence of retinal detachment (RD) at Soroka University Medical Center (1995–2010). 19 (50%) underwent scleral repair alone (control group) and the other 19 eyes were treated with PSB also (PSB group). We compared visual outcomes in these two groups and rates of subsequent postoperative complications. Results. Baseline characteristics of the groups were similar. Compared with the control group, the PSB group had statistically significant lower rates of proliferative vitreoretinopathy (PVR) (5.3% versus 38.4%, P < 0.05) and a trend towards lower rates of RD (15.8% versus 41.1%, P = 0.1). PSB group eyes had a statistically significant improvement of their best distance visual acuity (BDVA) with lower means of final BDVA-grade (P < 0.05) and logMAR vision (P < 0.05). Eyes in the control group had no improvement in these parameters. Conclusion. PSB procedure during posterior segment OGI repair may decrease the risk of subsequent retinal complications and improve final visual outcome.


Canadian Journal of Ophthalmology-journal Canadien D Ophtalmologie | 2009

The effect of Nd:YAG laser posterior capsulotomy on ocular wave front aberrations

Jaime Levy; Tova Lifshitz; Itamar Klemperer; Boris Knyazer; Zach Ashkenazy; Assaf Kratz; Nadav Belfair

OBJECTIVE To assess the effect of Nd:YAG laser posterior capsulotomy on ocular wave front aberrations. STUDY DESIGN Retrospective comparative study. PARTICIPANTS Twenty-four eyes of 24 consecutive pseudophakic patients with symptomatic PCO, who presented for Nd:YAG laser posterior capsulotomy at our clinic, were included in this study. METHODS The wave front aberrations of the entire optical path of 24 pseudophakic eyes of 24 patients before, and 1 month after, Nd:YAG laser posterior capsulotomy were measured using the Nidek Optical Path Difference (OPD) scan aberrometer. Total, tilt, and high-order aberrations, and total coma, total trefoil, total tetrafoil, total spherical, and total high astigmatism aberrations were analyzed statistically. Secondary measures included changes in visual acuity and refraction, and repeatability of wave front measurements in the fellow eye. RESULTS Before Nd:YAG laser posterior capsulotomy, the total higher-order aberrations root mean-square (RMS) wave front aberration was 2.08 (SD 2.20) microm, with total trefoil being a major contributor at 1.19 (SD 1.15) microm. One month after the procedure, significant decreases in total, tilt, and high-order aberrations, and total trefoil, total tetrafoil, total spherical, and total high astigmatism aberrations were noted (p< 0.05). No significant changes in total coma aberrations were found (p > 0.05). Additionally, significant improvement in visual acuity without significant change in refraction was observed. No statistically significant differences were detected in any of the RMS values of wave front measurements taken 1 month later in the fellow eye. CONCLUSIONS Nd:YAG laser posterior capsulotomy causes significant decrease in ocular wave front aberrations measured using the Nidek-OPD scan aberrometer, which can account for a better optical quality after the procedure. Further research to examine the impact of wave front aberrations in visual function after Nd:YAG laser posterior capsulotomy is needed.


Canadian Journal of Ophthalmology-journal Canadien D Ophtalmologie | 2006

Panuveitis as presenting sign of chickenpox in a young child

Nadav Belfair; Jaime Levy; Tova Lifshitz

CASE REPORT A previously healthy 2-year-old girl presented with severe panuveitis in her left eye. She developed chickenpox rash several days later. DNA particles of varicella-zoster virus (VZV) were detected by polymerase chain reaction (PCR) in the aqueous humor. No antiviral regimen was administered. The uveitis resolved completely after 1 week. COMMENTS Patients with chickenpox should undergo a thorough ophthalmologic examination at the onset of visual symptoms. Clinicians should be aware of the rare occurrence of chickenpox when evaluating a uveitis patient. If there is suspicion of chickenpox, the clinician may consider ordering serology or PCR tests.

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Dive into the Nadav Belfair's collaboration.

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Tova Lifshitz

Ben-Gurion University of the Negev

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Jaime Levy

Ben-Gurion University of the Negev

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Itamar Klemperer

Ben-Gurion University of the Negev

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Boris Knyazer

Ben-Gurion University of the Negev

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Assaf Kratz

Ben-Gurion University of the Negev

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Libe Gradstein

Ben-Gurion University of the Negev

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Shirley Rosen

Ben-Gurion University of the Negev

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Anry Pitchkhadze

Ben-Gurion University of the Negev

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Eyal Sheiner

Ben-Gurion University of the Negev

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Irit Szaingurten-Solodkin

Ben-Gurion University of the Negev

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