Publications

2017

Tu Y, Jakobiec F, Leung K, Freitag S. Distinguishing Benign from Malignant Circumscribed Orbital Tumors in Children. Semin Ophthalmol. 2017;:1–10.
An orbital neoplasm in children is an uncommon clinical finding. Clinical suspicion should be based on many factors, including its location, the nature of onset, associated systemic signs and symptoms, family and social histories, examination findings, and radiographic characteristics. We present two cases of young children of similar age with a rapid-onset orbital mass. In both cases, a circumscribed round lesion was found in the superomedial orbit. An orbital schwannoma, a benign and usually slow growing tumor, was found in the first patient. In contrast, the biopsy of the second patient, who was nearly asymptomatic, revealed a rhabdomyosarcoma. In this review, we have explored the differential diagnosis of relatively common circumscribed round orbital tumors in the pediatric population from both the radiographic (magnetic resonance imaging, MRI) and histopathologic perspectives. A review of highly unusual orbital tumors in children is also provided.
Yin J, Jurkunas U. Limbal Stem Cell Transplantation and Complications. Semin Ophthalmol. 2017;:1–8.
Corneal epithelial stem cells are adult somatic stem cells located at the limbus and represent the ultimate source of transparent corneal epithelium. When these limbal stem cells become dysfunctional or deficient, limbal stem cell deficiency (LSCD) develops. LSCD is a major cause of corneal scarring and is particularly prevalent in chemical and thermal burns of the ocular surface. LSCD leads to conjunctivalization of the corneal surface, neovascularization, recurrent or persistent epithelial defects, ocular surface inflammation, and scarring that, in turn, lead to decreased vision, pain, and impaired quality of life. Several techniques have been reported for limbal stem cell transplantation (LSCT). We introduce the surgical techniques, examine the success rate, and discuss the postoperative complications of conjunctival limbal autograft (CLAU), cultivated limbal stem cell transplantation (CLET), simple limbal epithelial transplantation (SLET), and limbal allograft, including keratolimbal allografts (KLAL) and living-related conjunctival allograft (LR-CLAL).
Zhang Q, Jing S, Cheng Z, Yu Z, Dehghan S, Shamsaddini A, Yan Y, Li M, Seto D. Comparative genomic analysis of two emergent human adenovirus type 14 respiratory pathogen isolates in China reveals similar yet divergent genomes. Emerg Microbes Infect. 2017;6(11):e92.
Human adenovirus type 14 (HAdV-B14p) was originally identified as an acute respiratory disease (ARD) pathogen in The Netherlands in 1955. For approximately fifty years, few sporadic infections were observed. In 2005, HAdV-B14p1, a genomic variant, re-emerged and was associated with several large ARD outbreaks across the U.S. and, subsequently, in Canada, the U.K., Ireland, and China. This strain was associated with an unusually higher fatality rate than previously reported for both this prototype and other HAdV types in general. In China, HAdV-B14 was first observed in 2010, when two unrelated HAdV-B14-associated ARD cases were reported in Southern China (GZ01) and Northern China (BJ430), followed by three subsequent outbreaks. While comparative genomic analysis, including indel analysis, shows that the three China isolates, with whole genome data available, are similar to the de Wit prototype, all are divergent from the U.S. strain (303600; 2007). Although the genomes of strains GZ01 and BJ430 are nearly identical, as per their genome type characterization and percent identities, they are subtly divergent in their genome mutation patterns. These genomes indicate possibly two lineages of HAdV-B14 and independent introductions into China from abroad, or subsequent divergence from one; CHN2012 likely represents a separate sub-lineage. Observations of these simultaneously reported emergent strains in China add to the understanding of the circulation, epidemiology, and evolution of these HAdV pathogens, as well as provide a foundation for developing effective vaccines and public health strategies, including nationwide surveillance in anticipation of larger outbreaks with potentially higher fatality rates associated with HAdV-B14p1.
Sood A, Pearce W, Workowski K, Lockwood J, Yeh S. Combined Intravitreal and Systemic Antibiotic Therapy in a Patient with Syphilitic Uveitis. Ocul Immunol Inflamm. 2017;:1–3.
PURPOSE: To report the novel use of combined intravitreal and systemic antibiotic therapy in a patient with syphilitic panuveitis and discuss the management of ocular syphilis. METHODS: Case report Results: A 45-year old heterosexual male with human immunodeficiency virus (HIV) presented with 1 month of blurry vision in both eyes. Clinical examination revealed a bilateral panuveitis. The patient denied history of genital lesions or rash, but did complain of difficulty hearing bilaterally. Treponemal EIA was positive, the RPR titer greater than 1:512 dilution, and CSF VDRL 1:4. A diagnosis of neurosyphilis and ocular syphilis was made based on the clinical and laboratory findings. The patient was admitted for systemic intravenous antibiotic therapy, but was noted to have a penicillin allergy. Intravitreal ceftazidime was promptly administered bilaterally to achieve treponemacidal levels of antibiotic therapy. After penicillin desensitization protocol, the patient received 14 days of intravenous penicillin with clinical resolution. CONCLUSIONS: There are increasing reports of ocular syphilis in the United States and delay in diagnosis and management can lead to severe visual impairment and blindness. We report the first case of adjunct intravitreal antibiotic therapy in a penicillin allergic patient. As ocular syphilis is a form of bacterial endophthalmitis, combination intravitreal and systemic antibiotics may be considered.
Kim J, Kanjlia S, Merabet L, Bedny M. Development of the Visual Word Form Area Requires Visual Experience: Evidence from Blind Braille Readers. J Neurosci. 2017;37(47):11495–11504.
Learning to read causes the development of a letter- and word-selective region known as the visual word form area (VWFA) within the human ventral visual object stream. Why does a reading-selective region develop at this anatomical location? According to one hypothesis, the VWFA develops at the nexus of visual inputs from retinotopic cortices and linguistic input from the frontotemporal language network because reading involves extracting linguistic information from visual symbols. Surprisingly, the anatomical location of the VWFA is also active when blind individuals read Braille by touch, suggesting that vision is not required for the development of the VWFA. In this study, we tested the alternative prediction that VWFA development is in fact influenced by visual experience. We predicted that in the absence of vision, the "VWFA" is incorporated into the frontotemporal language network and participates in high-level language processing. Congenitally blind (n = 10, 9 female, 1 male) and sighted control (n = 15, 9 female, 6 male), male and female participants each took part in two functional magnetic resonance imaging experiments: (1) word reading (Braille for blind and print for sighted participants), and (2) listening to spoken sentences of different grammatical complexity (both groups). We find that in blind, but not sighted participants, the anatomical location of the VWFA responds both to written words and to the grammatical complexity of spoken sentences. This suggests that in blindness, this region takes on high-level linguistic functions, becoming less selective for reading. More generally, the current findings suggest that experience during development has a major effect on functional specialization in the human cortex.SIGNIFICANCE STATEMENT The visual word form area (VWFA) is a region in the human cortex that becomes specialized for the recognition of written letters and words. Why does this particular brain region become specialized for reading? We tested the hypothesis that the VWFA develops within the ventral visual stream because reading involves extracting linguistic information from visual symbols. Consistent with this hypothesis, we find that in congenitally blind Braille readers, but not sighted readers of print, the VWFA region is active during grammatical processing of spoken sentences. These results suggest that visual experience contributes to VWFA specialization, and that different neural implementations of reading are possible.
Zhang M, Gilbert A, Hunter D. Superior oblique myokymia. Surv Ophthalmol. 2017;
Superior oblique myokymia (SOM) is a rare condition of unclear etiology. We discuss the history, etiology, clinical features, differential diagnoses, management and prognosis of SOM. We conducted a meta-analysis of all 116 cases published since SOM was first described in 1906. The age at examination was 17-72 years (mean 42 years.) There was a right-sided preponderance in 61% of cases (P < 0.02) that was statistically significant in females (63%, P < 0.04) but not in males (59%, P = 0.18). The pathophysiology of SOM may be neurovascular compression and/or ephaptic transmission. Although various pharmacological and surgical approaches to SOM treatment have been proposed, the rarity of the condition has made it impossible to conduct clinical trials evaluating the safety and efficacy of these approaches. Recently, topical beta-blockers have managed SOM symptoms in a number of cases, including the first case treated with levobunolol. Systemic medications, strabismus surgery, and neurosurgery have been used to control symptoms, with strabismus surgery carrying a moderate risk of post-operative diplopia in down-gaze. While there is no established treatment for SOM, we encourage clinicians to attempt topical levobunolol therapy before considering systemic therapy or surgery.
Bakthavatchalam M, Lai F, Rong SS, Ng D, Brelén M. Treatment of cystoid macular edema secondary to retinitis pigmentosa: A systematic review. Surv Ophthalmol. 2017;
There are various treatments for cystoid macular edema (CME) secondary to retinitis pigmentosa (RP); however, the evidence for these treatments has not been previously systematically reviewed. Our review that includes 23 studies shows that oral carbonic anhydrase inhibitors (CAI) (including acetazolamide, methazolamide) and topical CAI (dorzolamide and brinzolamide) are effective first line treatments. In patients unresponsive to CAI treatment, intravitreal steroids (triamcinolone acetonide and sustained-release dexamethasone implant), oral corticosteroid (Deflazacort), intravitreal anti-vascular endothelial growth factor agents (ranibizumab and bevacizumab), grid laser photocoagulation, pars plana vitrectomy, or ketorolac were also effective in improving CME secondary to RP. Oral acetazolamide has the strongest clinical basis for treatment and was superior to topical dorzolamide. Rebound of CME was commonly seen in the long term, regardless of the choice of treatment. Oral acetazolamide should be the first line treatment in CME secondary to RP. Topical dorzolamide is an appropriate alternative in patients intolerant to adverse effects of oral acetazolamide. More studies are required to investigate the management of rebound CME.
Bouffard M, Cestari D. Diplopia after Cataract Extraction. Semin Ophthalmol. 2017;:1–6.
Diplopia after cataract extraction is an unexpected outcome for the patient and often a source of confusion for the physician, owing to its relative infrequency. This article reviews the pertinent literature on the subject. Mechanisms include anesthetic myotoxicity, surgical trauma, optical aberrations, cortical disorders in patients with congenital strabismus, and the unmasking of previously unnoticed ocular misalignment. As the population continues to age and cataract extraction is performed in increasing volume, familiarity with this uncommon but important outcome may help to clarify and effectively treat post-cataract-extraction diplopia.