Proptosis Caused by Rhabdomyomatous Mesenchymal Hamartomata Occurring in the Orbit.

Two infants were referred for progressive orbital proptosis. MRI in both cases demonstrated a homogenous mass in the orbit adherent to and isointense with a rectus muscle. Histopathology in both cases demonstrated a bland proliferation of spindle cells with entrapped skeletal muscle. Immunochemistry demonstrated that the abnormal tissue was of skeletal muscle origin, consistent with rhabdomyomatous mesenchymal hamartoma (RMH). Observation was elected due to the reported benign nature of RMH. In contrast to RMH of the cutaneous tissues that typically follows a benign course, RMH of the orbit may present with rapid growth.

Defective retinal vascular endothelial cell development as a consequence of impaired integrin αVß8-mediated activation of transforming growth factor-ß.

Deletions of the genes encoding the integrin αVß8 (Itgav, Itgb8) have been shown to result in abnormal vascular development in the CNS, including prenatal and perinatal hemorrhage. Other work has indicated that a major function of this integrin in vivo is to promote TGFß activation. In this paper, we show that Itgb8 mRNA is strongly expressed in murine Müller glia and retinal ganglion cells, but not astrocytes. We further show that Itgb8 deletion in the entire retina severely perturbs development of the murine retinal vasculature, elevating vascular branch point density and vascular coverage in the superficial vascular plexus, while severely impairing formation of the deep vascular plexus. The stability of the mutant vasculature is also impaired as assessed by the presence of hemorrhage and vascular basal lamina sleeves lacking endothelial cells. Specific deletion of Itgb8 in Müller glia and neurons, but not deletion in astrocytes, recapitulates the phenotype observed following Itgb8 in the entire retina. Consistent with αVß8's role in TGFß1 activation, we show that retinal deletion of Tgfb1 results in very similar retinal vascular abnormalities. The vascular deficits appear to reflect impaired TGFß signaling in vascular endothelial cells because retinal deletion of Itgb8 reduces phospho-SMAD3 in endothelial cells and endothelial cell-specific deletion of the TGFßRII gene recapitulates the major deficits observed in the Itgb8 and TGFß1 mutants. Of special interest, the retinal vascular phenotypes observed in each mutant are remarkably similar to those of others following inhibition of neuropilin-1, a receptor previously implicated in TGFß activation and signaling.

Blindness from orbital varices: case report.

A 41-year-old woman presented with a 21-year history of a left orbital mass. She reported 3 distinct episodes of sudden proptosis, periorbital bruising, pain, nausea and vomiting with resulting stepwise deterioration in her vision. Her symptoms resolved spontaneously over several days, with the exception of loss in vision, which persisted. Examination was notable for ipsilateral enophthalmos in primary gaze. With Valsalva she developed proptosis. Magnetic resonance imaging (MRI) demonstrated a left orbital apex malformation consistent with a varix. She had no light perception on the left with end-stage optic atrophy. This case illustrates the severity of visual loss that can occur with orbital varices.

Trends in Radiation Practices for Female Ocular Oncologists in North America: A Collaborative Study of the International Society of Ocular Oncology.

BACKGROUND: The aim of this study was to determine the known radiation exposure, attitudes, and consequent risk modifications among female ocular oncologists in North America who routinely administer radioactive plaque brachytherapy treatment and are members of the International Society of Ocular Oncology. METHODS: Nineteen female ocular oncologists completed an anonymous 17-question radiation exposure survey. RESULTS: Eleven of the participants chose to routinely wear lead protection during surgery; 8 did not. Fifteen of 19 participants reported using an unloaded "nonactive" template to prepare for plaque implantation. During pregnancy, 11 of 13 participants continued to perform plaque brachytherapy. Eight of these 11 undertook measures to decrease radiation exposure self-reported as lead wear and other. The average reported anxiety regarding fertility was 2.1 (SD, 2.2) on a scale from 1 to 10. CONCLUSION: This study corroborates prior literature that surgeons' exposure to radiation during plaque brachytherapy is minimal. Nonetheless, there remains some anxiety regarding exposure risk to women, due to potential effects on fertility and fetal health. We found variability in exposure monitoring, required training, and precautions during pregnancy amongst this group of surgeons. Improved education and clearer pregnancy guidelines may equip female ocular oncologists with optimal knowledge regarding risk of radiation exposure.