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Dive into the research topics where Robert O. Hoffman is active.

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Featured researches published by Robert O. Hoffman.


Neuro-oncology | 2012

Visual outcomes in children with neurofibromatosis type 1-associated optic pathway glioma following chemotherapy: a multicenter retrospective analysis

Michael J. Fisher; M Loguidice; David H. Gutmann; Robert Listernick; Rosalie E. Ferner; Nicole J. Ullrich; Roger J. Packer; Uri Tabori; Robert O. Hoffman; Simone L. Ardern-Holmes; Trent R. Hummel; Darren Hargrave; Eric Bouffet; Joel Charrow; Larissa T. Bilaniuk; Laura J. Balcer; Grant T. Liu

Optic pathway gliomas (OPGs) occur in 15%-20% of children with neurofibromatosis type 1 (NF1); up to half become symptomatic. There is little information regarding ophthalmologic outcomes after chemotherapy. A retrospective multicenter study was undertaken to evaluate visual outcomes following chemotherapy for NF1-associated OPG, to identify risks for visual loss, and to ascertain indications for treatment. Subjects included children undergoing initial treatment for OPGs with chemotherapy between January 1997 and December 2007. Of 115 subjects, visual acuity (VA) decline and tumor progression were the primary reasons to initiate treatment, although there were significant differences in the pattern of indications cited among the institutions. Eighty-eight subjects and 168 eyes were evaluable for VA outcome. At completion of chemotherapy, VA improved (32% of subjects), remained stable (40%), or declined (28%). Tumor location was the most consistent prognostic factor for poor VA outcome. There was poor correlation between radiographic and VA outcomes. Although visual outcomes for NF1-associated OPG are not optimal, approximately one-third of children regain some vision with treatment. Since radiographic outcomes do not predict visual outcomes, their use as the primary measure of treatment success is in question. The lack of consensus regarding the indications for treatment underlines the need for better standardization of care. Future clinical trials for OPG require standardized visual assessment methods and clear definitions of visual outcomes.


Journal of Developmental and Behavioral Pediatrics | 1996

Children and adolescents with neurofibromatosis 1 : A behavioral phenotype

Constance V. Dilts; John C. Carey; John C. Kircher; Robert O. Hoffman; Donnell J. Creel; Kenneth Ward; Elaine Clark; Claire O. Leonard

Twenty 6− to 17-year-old children with neurofibromatosis 1 (NF1) were compared to 20 age-and sex-matched siblings on a wide range of neuropsychological and behavioral dimensions. In familial cases, diagnostic status was confirmed by gene linkage with greater than 98% accuracy. Visual examinations that included assessments of visual evoked responses (VER) were performed on subjects with NF1. Forty-two percent of NF1 subjects had abnormal VER and underwent magnetic resonance imagery or computed tomography scans of the brain. On a variety of skills, subjects with NF1 performed more poorly than unaffected siblings. Children with NF1 were found to be less competent on measures of cognitive, language, and motor development, visual-spatial judgment, visual-motor integration, and academic achievement. Learning disabilities were common in children with NF1. Parents and teachers reported that NF1 subjects had internalizing problems and difficulty interacting with peers. A behavioral phenotype for NF1 and recommendations for preventative interventions are proposed.


Journal of Cataract and Refractive Surgery | 2008

Intraoperative performance and postoperative outcomes of endocapsular ring implantation in pediatric eyes

Vaishali Vasavada; Viraj A. Vasavada; Robert O. Hoffman; Terrence S. Spencer; Rishi V. Kumar; Alan S. Crandall

PURPOSE: To study the intraoperative performance and postoperative outcomes of Cionni modified capsule tension ring (CTR) and intraocular lens (IOL) implantation in the capsular bag in pediatric eyes with ectopia lentis. SETTING: John A. Moran Eye Center, Salt Lake City, Utah, USA. METHODS: Thirty‐five eyes (22 children) with ectopia lentis and visually significant cataract that had lens aspiration and in‐the‐bag implantation of single‐piece AcrySof IOL and Cionni CTR were included. Single‐ and double‐eyelet CTRs were used. The rings were sutured to the sclera using 9‐0 or 10‐0 polypropylene (Prolene) sutures. Preoperative and postoperative best corrected visual acuity (BCVA), intraoperative performance, IOL centration, and complications were studied. RESULTS: The mean patient age was 8.2 years ± 5.1 (SD) and the median follow‐up, 28 months. A double‐eyelet CTR was implanted in 12 eyes and a single‐eyelet CTR, in 23 eyes. The mean BCVA at the final follow‐up (0.37 ± 0.25 logMAR, 33 eyes) was significantly better than preoperatively (0.78 ± 0.42 logMAR, 28 eyes) (P = .003). At the last examination, the BCVA was 20/40 or better in 16 eyes (45.7%). Three eyes (8.5%) required resuturing for IOL decentration. Nineteen eyes (54.3%) had a secondary procedure for posterior capsule opacification. Other complications included anterior capsule opacification (2.85%), cystoid macular edema (5.71%), chronic uveitis (5.71%), and vitreous prolapse (2.85%). CONCLUSION: Implantation of the Cionni CTR and single‐piece AcrySof IOL in the capsular bag in pediatric eyes with subluxated lenses was safe and effective and led to a stable IOL with few significant complications.


Investigative Ophthalmology & Visual Science | 2013

Blue-light reflectance imaging of macular pigment in infants and children.

Paul S. Bernstein; Mohsen Sharifzadeh; Aihua Liu; Igor V. Ermakov; Kelly Nelson; Xiaoming Sheng; Cynthia Panish; Bonnie Carlstrom; Robert O. Hoffman; Werner Gellermann

PURPOSE While the role of the macular pigment carotenoids in the prevention of age-related macular degeneration has been extensively studied in adults, comparatively little is known about the physiology and function of lutein and zeaxanthin in the developing eye. We therefore developed a protocol using a digital video fundus camera (RetCam) to measure macular pigment optical density (MPOD) and distributions in premature infants and in children. METHODS We used blue light reflectance to image the macular pigment in premature babies at the time of retinopathy of prematurity (ROP) screening and in children aged under 7 years who were undergoing examinations under anesthesia for other reasons. We correlated the MPOD with skin carotenoid levels measured by resonance Raman spectroscopy, serum carotenoids measured by HPLC, and dietary carotenoid intake. RESULTS We enrolled 51 infants and children ranging from preterm to age 7 years. MPOD correlated significantly with age (r = 0.36; P = 0.0142), with serum lutein + zeaxanthin (r = 0.44; P = 0.0049) and with skin carotenoid levels (r = 0.42; P = 0.0106), but not with dietary lutein + zeaxanthin intake (r = 0.13; P = 0.50). All premature infants had undetectable macular pigment, and most had unusually low serum and skin carotenoid concentrations. CONCLUSIONS Our most remarkable finding is the undetectable MPOD in premature infants. This may be due in part to foveal immaturity, but the very low levels of serum and skin carotenoids suggest that these infants are carotenoid insufficient as a consequence of low dietary intake and/or severe oxidative stress. The potential value of carotenoid supplementation in the prevention of ROP and other disorders of prematurity should be a fruitful direction for further investigation.


Investigative Ophthalmology & Visual Science | 2013

Interrelationships Between Maternal Carotenoid Status and Newborn Infant Macular Pigment Optical Density and Carotenoid Status

Bradley S. Henriksen; Gary Chan; Robert O. Hoffman; Mohsen Sharifzadeh; Igor V. Ermakov; Werner Gellermann; Paul S. Bernstein

PURPOSE Deposition of the macular pigment carotenoids lutein and zeaxanthin in the human retina occurs early in life. In this study, we examined the interrelationships of maternal carotenoid status and newborn infant macular pigment levels and systemic carotenoid status. As a secondary measure, we also evaluated the effects of intrauterine growth restriction (IUGR) on carotenoid status in term newborn infants. METHODS We measured mother and infant skin carotenoids using resonance Raman spectroscopy (RRS), serum carotenoids by HPLC, and mother breast milk carotenoids by HPLC. We measured infant macular pigment levels using noninvasive blue light reflectometry. RESULTS We enrolled 30 healthy term infants, their mothers, and 10 IUGR infants and their mothers. A subset of 16 infants was imaged for macular pigment optical density (MPOD). Infant serum zeaxanthin levels correlated with MPOD (r = 0.68, P = 0.007). Mother serum zeaxanthin levels correlated with infant MPOD (r = 0.59, P = 0.032). Infant and mother serum lutein did not correlate with MPOD. Mother-infant correlations were found for total serum carotenoids (r = 0.42, P = 0.020) and skin carotenoids (r = 0.48, P = 0.001). No difference was seen between IUGR infants and controls in total serum or skin carotenoids. Mothers of IUGR infants had lower total serum carotenoids (P = 0.019) and breast milk carotenoids than controls (P = 0.006). CONCLUSIONS Our findings suggest that maternal zeaxanthin status may play a more important role than lutein status in macular pigment deposition in utero. Controlled trials are needed to determine whether maternal zeaxanthin prenatal supplementation can raise infant macular pigment levels and/or improve ocular function.


Cornea | 2001

Surgical treatment of an intrastromal epithelial corneal cyst.

Mark D. Mifflin; Timothy L. Byers; Richard L. Elliot; Robert O. Hoffman

Purpose. To describe corneal intrastromal epithelial cysts and present a minimally invasive surgical technique successfully used to treat such a lesion. Methods. A 5-year-old girl with a progressive, vision-threatening, intrastromal corneal opacity in the left eye is described. The patient had a history of accommodative esotropia and bilateral medial rectus recession two years before presentation. A presumptive diagnosis of an epithelial cyst secondary to iatrogenic seeding of the limbal corneal stroma was made. Because of documented growth toward the visual axis and a decrease in best-corrected visual acuity, surgical treatment was initiated. The cyst was incised and debrided through a 2.0-mm, partial-thickness, limbus-parallel, clear corneal incision. Results. Cytologic analysis of the cyst contents showed intact and degenerated epithelial cells, thereby confirming the diagnosis. The cyst walls were scraped through the nonenlarged incision, and irrigation resulted in nearly complete clearing of the opacity. Stable vision and no recurrences were documented with 21 months of follow-up. Conclusion. This minimally invasive surgical approach may be a good alternative to previously described treatments for intrastromal corneal cysts.


Journal of Pediatric Ophthalmology & Strabismus | 2014

Ophthalmologic Features of Vici Syndrome

Francis M. Filloux; Robert O. Hoffman; David H. Viskochil; Heinz Jungbluth; Donnell J. Creel

PURPOSE To report and compile the ophthalmological features critical to diagnosis of Vici syndrome, a rare congenital disorder characterized principally by agenesis of the corpus callosum, cataracts, cardiomyopathy, immune defects, and hypopigmentation. METHODS A child with Vici syndrome (OMIM 242840) is reported with emphasis on the ophthalmologic evaluation. Ophthalmologic assessments including fundus examination, visual evoked potentials (VEPs), and ocular coherence tomography are presented. These findings are compared with those identified in other published cases of children with Vici syndrome. RESULTS Ophthalmologic findings included bilateral nuclear and anterior polar cataracts, bilateral optic nerve atrophy, and mild fundus hypopigmentation. Evoked potentials recorded across the mid-occipital scalp demonstrated misrouting of optic pathways typical of albinism. Optical coherence tomography exhibited a poorly defined fovea demonstrating a lesser degree of foveal depression also consistent with ocular albinism. Review of reported children with Vici syndrome identifies bilateral cataracts, nystagmus, fundus hypopigmentation, visual impairment, and optic nerve hypoplasia as common ophthalmologic features. CONCLUSIONS Ophthalmologic findings are critical to the diagnosis of Vici syndrome. Most common are bilateral cataracts and relative fundus hypopigmentation. VEPs can identify misrouting of optic pathways typical of ocular albinism, thereby establishing the diagnosis in challenging cases.


PLOS ONE | 2017

Retinopathy of prematurity: A comprehensive risk analysis for prevention and prediction of disease

Leah A. Owen; Margaux A. Morrison; Robert O. Hoffman; Bradley A. Yoder; Margaret M. DeAngelis

Background Retinopathy of prematurity (ROP) is a blinding morbidity of preterm infants. Our current screening criteria have remained unchanged since their inception and lack the ability to identify those at greatest risk. Objectives We sought to comprehensively analyze numerous proposed maternal, infant, and environmental ROP risk variables in a robustly phenotyped population using logistic regression to determine the most predictive model for ROP development and severity. We further sought to determine the statistical interaction between significant ROP risk variables, which has not previously been done in the field of ROP. We hypothesize that our comprehensive analysis will allow for better identification of risk variables that independently correlate with ROP disease. Going forward, this may allow for improved infant risk stratification along a time continuum from prenatal to postnatal development, making prevention more feasible. Methods We performed a retrospective cohort analysis of preterm infants referred for ROP screening in one neonatal intensive care unit from 2010–2015. The primary outcome measure was presence of ROP. Secondary outcome measures were ROP requiring treatment and severe ROP not clearly meeting current treatment criteria. Univariate, stepwise regression and statistical interaction analyses of 57 proposed ROP risk variables was performed to identify variables which were significantly associated with each outcome measure. Results We identified 457 infants meeting our inclusion criteria. Within this cohort, numerous factors showed a significant individual association with our ROP outcome measures; however, stepwise regression analysis found the most predictive model for overall ROP risk included estimated gestational age, birth weight, the need for any surgery, and maternal magnesium prophylaxis. The corresponding Area Under the Curve (AUC) for this model was 0.8641, while the traditional model of gestational age and birth weight predicted ROP disease less well with an AUC of 0.8489. Development of severe ROP was best predicted by estimated gestational age (week), the need for any surgery and increased probability of death or moderate-severe BPD at 7 days. Finally, the model most predictive for type 1 ROP included estimated gestational age (week) and the presence of severe chronic lung disease. No significant statistical interaction was found between variables. Conclusions Our work is unique as we report comprehensive analysis of the greatest number of proposed ROP risk variables to date in a robustly phenotyped population. We describe novel risk models for our ROP outcome measures and demonstrate independence of these variables using statistical modeling not previously applied to ROP. This may better allow for individual infant risk stratification and importantly mitigation of future risk.


European Journal of Medical Genetics | 2012

Mosaicism in Stickler syndrome.

David A. Stevenson; Rena J. Vanzo; Kristy Damjanovich; Heather Hanson; Harlan R. Muntz; Robert O. Hoffman; Pinar Bayrak-Toydemir

Stickler syndrome is a heterogeneous condition due to mutations in COL2A1, COL11A1, COL11A2, and COL9A1. To our knowledge, neither non-penetrance nor mosaicism for COL2A1 mutations has been reported for Stickler syndrome. We report on a family with two clinically affected sibs with Stickler syndrome who have clinically unaffected parents. Both sibs have a novel heterozygous mutation in exon 26 of COL2A1 (c.1525delT); this results in a premature termination codon downstream of the mutation site. One parent was found to have low level mosaicism in DNA extracted from whole blood. This scenario encourages consideration of molecular testing in seemingly unaffected parents for recurrence risks and potential screening for mild age-related manifestations.


Ocular Immunology and Inflammation | 2013

Cryopyrin-associated periodic syndromes and the eye.

Thomas J. Oberg; Albert T. Vitale; Robert O. Hoffman; John F. Bohnsack; Judith E. A. Warner

Aim: To describe the ophthalmologic findings in two patients with Muckle-Wells Syndrome, a phenotype of the Cryopyrin Associated Periodic Syndromes (CAPS) spectrum. There is currently sparse ophthalmic literature regarding the ocular manifestations of CAPS. We hope to increase awareness of this spectrum of diseases and the importance of proper treatment amongst eye care professionals. Methods: Interventional Case Series. Results: Patient 1 experienced resolution of aseptic meningitis, papilledema, and anterior uveitis following treatment with anikinra. Patient 2 experienced resolution of panuveitis following treatment with anikinra. Conclusions: The severe ocular manifestations of the most severe CAPS phenotype, Chronic Infantile Neurological Cutaneous and Articular Syndrome/Neonatal Onset Multisystem Inflammatory Disease Syndrome (CINCA/NOMID) have been previously described. There is increasing evidence that patients may experience similar ocular disease with the milder phenotype of Muckle-Wells Sydnrome. There is also increasing evidence that appropriate therapy can have a profound effect on patient prognosis.

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David H. Gutmann

Washington University in St. Louis

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Grant T. Liu

University of Pennsylvania

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M Loguidice

University of Pennsylvania

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Michael J. Fisher

Children's Hospital of Philadelphia

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Nicole J. Ullrich

Boston Children's Hospital

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Roger J. Packer

Children's National Medical Center

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Rosalie E. Ferner

Guy's and St Thomas' NHS Foundation Trust

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