Outcomes of Nontuberculous Mycobacterial Keratitis After Clear Corneal Incision Phacoemulsification Surgery: A Case Series of 6 Eyes in South Florida.

PURPOSE: The purpose of this study was to present the successful management and outcomes in a series of 6 cases of culture-positive nontuberculous mycobacterial keratitis after clear corneal incision phacoemulsification surgery. METHODS: This is a case series of 6 consecutive eyes that presented at the Cornea Division at an academic institution, diagnosed with culture-positive nontuberculous mycobacterial keratitis after phacoemulsification surgery. RESULTS: Six eyes of 5 patients were included. The mean interval from cataract surgery to presentation was 7.7 weeks. All cases presented with intrastromal abscesses adjacent to corneal incisions, and 2 had scleral extension of the infection. Isolated organisms were Mycobacterium abscessus (n = 4), Mycobacterium chelonae (n = 1), and Mycobacterium mucogenicum (n = 1). All cases were treated with topical amikacin 8 mg/mL for 10.5 weeks on average. All cases received either oral clarithromycin at 500 mg twice-daily dosage or oral azithromycin at 500 mg daily. Two patients with scleral abscesses underwent surgical debridement with amniotic membrane grafts. All 6 eyes achieved infection resolution and good visual recovery, with the final visual acuity ranging from 20/20 to 20/60. None of the patients experienced recurrence of infection. CONCLUSIONS: Prompt medical treatment with combined topical and oral therapy can lead to infection resolution and favorable visual recovery. Early surgical intervention can ensure good outcomes in cases of scleral extension.

Complete Resolution of Traumatic Indirect Carotid-Cavernous Fistula Two Years After Inciting Event.

Indirect carotid cavernous fistulas (CCFs) are most often spontaneous, but can rarely be caused by trauma. With traumatic etiology, the timeline for the development of symptoms varies significantly and can be difficult to predict. In this report, we discuss the case of a patient found to have an indirect CCF who presented for acutely worsening ocular symptoms and a history of pulsatile tinnitus that began two years prior after a suspected inciting head injury. To our knowledge, no cases have described a traumatic indirect CCF with a similarly extensive indolent course who demonstrated full symptomatic recovery following treatment.

Retinopathy in a Full-Term Infant with Cri-du-Chat Syndrome.

Cri-du-chat (CdC) is a 5p chromosomal deletion syndrome. CdC has numerous systemic associations but only a few ocular manifestations have been documented. In this report we present novel ocular findings of peripheral avascular retina and retinal hemorrhages in a full-term female infant, born to non-consanguineous parents, who had clinical features of cri-du-chat syndrome and genetic confirmation. The retinal hemorrhages resolved. However, the temporal avascular retina in our full-term patient remained. Further analysis of the 5p locus showed 3 genes: CTNND2, SEMA5A and SLC6A18 that not only fit our patient's external phenotype and ophthalmoscopic findings of retinal hemorrhages, but were also key in proper ocular development and neurogenesis, suggesting a genetic contribution by the short-arm of chromosome 5 to proper retinal maturation. Given these findings and their association with cri-du-chat, special attention on screening examinations should include a thorough evaluation of retinal vascularization in CdC patients, even in full-term neonates.

COMPARISON OF 2D AND 3D VIDEO DISPLAYS FOR TEACHING VITREORETINAL SURGERY.

PURPOSE: To compare medical students' learning uptake and understanding of vitreoretinal surgeries by watching either 2D or 3D video recordings. METHODS: Three vitreoretinal procedures (tractional retinal detachment, exposed scleral buckle removal, and four-point scleral fixation of an intraocular lens [TSS]) were recorded simultaneously with a conventional recorder for two-dimensional viewing and a VERION 3D HD system using Sony HVO-1000MD for three-dimensional viewing. Two videos of each surgery, one 2D and the other 3D, were edited to have the same content side by side. One hundred UMass medical students randomly assigned to a 2D group or 3D, then watched corresponding videos on a MacBook. All groups wore BiAL Red-blue 3D glasses and were appropriately randomized. Students filled out questionnaires about surgical steps or anatomical relationships of the pathologies or tissues, and their answers were compared. RESULTS: There was no significant difference in comprehension between the two groups for the extraocular scleral buckle procedure. However, for the intraocular TSS and tractional retinal detachment videos, the 3D group performed better than 2D (P < 0.05) on anatomy comprehension questions. CONCLUSION: Three-dimensional videos may have value in teaching intraocular ophthalmic surgeries. Surgical procedure steps and basic ocular anatomy may have to be reviewed to ensure maximal teaching efficacy.

Loss of citron kinase affects a subset of progenitor cells that alters late but not early neurogenesis in the developing rat retina.

PURPOSE: To understand how loss of citron kinase (CitK) affects retinal progenitor cells (RPCs) in the developing rat retina. METHODS: We compared knockout (KO) and wild-type (WT) retinae by immunohistochemistry. The TdT-mediated dUTP terminal nick-end labeling (TUNEL) assay was performed to determine cell death. Pulse-chase experiments using 5-ethynyl-2'-deoxyuridine (EdU) were carried out to interrogate RPC behavior and in turn neurogenesis. RESULTS: Reverse transcription-polymerase chain reaction analysis showed that CitK was expressed at embryonic day (E)12 and was turned off at approximately postnatal day (P)4. Immunohistochemistry showed CitK being localized as puncta at the apical end of the outer neuroblastic layer (ONBL). Analyses during embryonic development showed that the KO retina was of comparable size to that of WT until E13. However, by E14, there was a reduction in the number of S-phase RPCs with a concomitant increase in TUNEL+ cells in the KO retina. Moreover, early neurogenesis, as reflected by retinal ganglion cell production, was not affected. Postnatal analysis of the retina showed that ONBL in the KO retina was reduced to half the size of that in WT and showed further degeneration. Immunohistochemistry revealed absence of Islet1+ bipolar cells at P2, which was further confirmed by EdU pulse-chase experiments. The CitK KO retinae underwent complete degeneration by P14. CONCLUSIONS: Our study showed that CitK is not required for a subset of RPCs before E14, but is necessary for RPC survival post E14. This in turn results in normal early embryonic neurogenesis, but severely compromised later embryonic and postnatal neurogenesis.

The expression analysis of Sfrs10 and Celf4 during mouse retinal development.

Processing of mRNAs including, alternative splicing (AS), mRNA transport and translation regulation are crucial to eukaryotic gene expression. For example, >90% of the genes in the human genome are known to undergo alternative splicing thereby expanding the proteome production capacity of a limited number of genes. Similarly, mRNA export and translation regulation plays a vital role in regulating protein production. Thus, it is important to understand how these RNA binding proteins including alternative splicing factors (ASFs) and mRNA transport and translation factors regulate these processes. Here we report the expression of an ASF, serine-arginine rich splicing factor 10 (Sfrs10) and a mRNA translation regulation factor, CUGBP, elav like family member 4 (Celf4) in the developing mouse retina. Sfrs10 was expressed throughout postnatal (P) retinal development and was observed progressively in newly differentiating neurons. Immunofluorescence (IF) showed Sfrs10 in retinal ganglion cells (RGCs) at P0, followed by amacrine and bipolar cells, and at P8 it was enriched in red/green cone photoreceptor cells. By P22, Sfrs10 was observed in rod photoreceptors in a peri-nuclear pattern. Like Sfrs10, Celf4 expression was also observed in the developing retina, but with two distinct retinal isoforms. In situ hybridization (ISH) showed progressive expression of Celf4 in differentiating neurons, which was confirmed by IF that showed a dynamic shift in Celf4 localization. Early in development Celf4 expression was restricted to the nuclei of newly differentiating RGCs and later (E16 onwards) it was observed in the initial segments of RGC axons. Later, during postnatal development, Celf4 was observed in amacrine and bipolar cells, but here it was predominantly cytoplasmic and enriched in the two synaptic layers. Specifically, at P14, Celf4 was observed in the synaptic boutons of rod bipolar cells marked by Pkc-α. Thus, Celf4 might be regulating AS early in development besides its known role of regulating mRNA localization/translation. In all, our data suggests an important role for AS and mRNA localization/translation in retinal neuron differentiation.