The medial ganglionic eminence (MGE) gives rise to the majority of mouse forebrain interneurons. Here, we examine the lineage relationship among MGE-derived interneurons using a replication-defective retroviral library containing a highly diverse set of DNA barcodes. Recovering the barcodes from the mature progeny of infected progenitor cells enabled us to unambiguously determine their respective lineal relationship. We found that clonal dispersion occurs across large areas of the brain and is not restricted by anatomical divisions. As such, sibling interneurons can populate the cortex, hippocampus striatum, and globus pallidus. The majority of interneurons appeared to be generated from asymmetric divisions of MGE progenitor cells, followed by symmetric divisions within the subventricular zone. Altogether, our findings uncover that lineage relationships do not appear to determine interneuron allocation to particular regions. As such, it is likely that clonally related interneurons have considerable flexibility as to the particular forebrain circuits to which they can contribute.

The cornea is the shield to the foreign world and thus, a primary site for peripheral infections. However, transparency and vision are incompatible with inflammation and scarring that may result from infections. Thus, the cornea is required to perform a delicate balance between fighting infections and preserving vision. To date, little is known about the specific role of antigen-presenting cells in viral keratitis. In this study, utilizing an established murine model of primary acute herpes simplex virus (HSV)-1 keratitis, we demonstrate that primary HSV keratitis results in increased conventional dendritic cells (cDCs) and macrophages within 24 hours after infection. Local depletion of cDCs in CD11c-DTR mice by subconjuntival diphtheria toxin injections, led to increased viral proliferation, and influx of inflammatory cells, resulting in increased scarring and clinical keratitis. In addition, while HSV infection resulted in significant corneal nerve destruction, local depletion of cDCs resulted in a much more severe loss of corneal nerves. Further, local cDC depletion resulted in decreased corneal nerve infection, and subsequently decreased and delayed systemic viral transmission in the trigeminal ganglion and draining lymph node, resulting in decreased mortality of mice. In contrast, sham depletion or depletion of macrophages through local injection of clodronate liposomes had neither a significant impact on the cornea, nor an effect on systemic viral transmission. In conclusion, we demonstrate that corneal cDCs may play a primary role in local corneal defense during viral keratitis and preserve vision, at the cost of inducing systemic viral dissemination, leading to increased mortality.

IMPORTANCE: Asymmetric horizontal strabismus surgery is often performed to correct primary gaze alignment without considering the symptoms that may result from misalignment in the patient's side gaze. Surgical choices influence alignment in side gaze and may contribute to functional and social deficits. OBJECTIVE: To identify the surgical procedures associated with changes of alignment in side gaze to help inform surgical planning for patients with horizontal strabismus. DESIGN, SETTING, AND PARTICIPANTS: The medical records of 1081 horizontal strabismus surgical procedures that were performed at Boston Children's Hospital during a 2-year period were retrospectively reviewed. Only records with strabismus measurements recorded in the right and left gaze before and after surgery were included. Data analysis was conducted from September 1, 2012, through June 7, 2015. MAIN OUTCOMES AND MEASURES: Change in comitance (CIC), determined by measuring the horizontal comitance (the difference between right- and left-gaze strabismus measurements) before and after surgery. RESULTS: The review identified 569 patients who met the inclusion criteria. Of the 491 patients with comitant preoperative alignment, 59 developed postoperative incomitance, of whom 53 (89.9%) had asymmetric surgery. Of the 78 patients with incomitant preoperative alignment, 36 patients' (46.2%) deviation had improved to comitance after surgery; 32 (88.9%) of these patients had asymmetric surgery. Asymmetric 2-muscle surgery had a median CIC of 4.0 while symmetric 2-muscle surgery had a median CIC of 1.5 (difference in CIC, 2.5; 95% CI, 2.0-3.0; P < .001). A CIC of 25 prism diopters or more was observed in 6 patients who underwent asymmetric surgery (0 with symmetric surgery). New postoperative incomitance was symptomatic in at least 17 patients (28.8%). CONCLUSIONS AND RELEVANCE: Asymmetric strabismus surgery can treat incomitant deviations, but it can also create symptomatic incomitant deviations in patients who were previously comitant. Surgical planning should include consideration of the potential for CIC, including the potential for unsatisfactory appearance in side gaze. Patients with binocular vision will be sensitive to diplopia in any gaze direction; in such cases, the consequences of asymmetric surgery should be considered with particular care.

Neuroendocrine malignancies-tumors characterized by the production of dense-core secretory granules-are most often encountered in the lungs and can also be found in extrapulmonary sites. Our patient had a primary neuroendocrine tumor of the antrum with an elusive cell of origin that secondarily invaded the inferior orbit. In the sinuses, neuroendocrine tumors may be confused with infectious sinusitis or squamous cell carcinoma. There are no known pathognomonic clinical or radiographic signs to distinguish these tumors from other conditions. Diagnosis depends on a biopsy with histopathologic and immunohistochemical analysis to identify biomarkers such as synaptophysin, chromogranin, CD56 and neuron specific enolase. Our patient's tumor defied precise immunohistochemical characterization because of its primitive character and erratic biomarker expression. The diagnosis oscillated between a neuroendocrine carcinoma and an ectopic esthesioneuroblastoma grade IV-hence the use of the more generic nosologic category of neuroendocrine neoplasm without specifying a neuronal or epithelial origin. Data to guide management are limited, particularly in the ophthalmic literature, and derive from experience with tumors of the sinonasal compartments. In the present case of a sino-orbital high grade neuroendocrine neoplasm, regional lymph node metastases developed shortly after presentation. The tumor has responded well to chemotherapy and radiation, but recurrence is often encountered within 2 years in this class of neoplasms.

Mucormycosis is a rare often fatal opportunistic fungal infection. It is typically described in patients with diabetes in ketoacidotic status and is rare in renal transplant recipients. Calciphylaxis is a rare and highly morbid disease of vascular calcification affecting patients with end-stage renal disease (ESRD). The first case of a renal transplant recipient who was inflicted with both rhinoorbitocerebral mucormycosis and calciphylaxis is reported. A 45-year-old man presented with 2-day history of left upper blepharoptosis, periorbital pain, left-sided headache, binocular diplopia, and left V2 numbness. He had undergone renal transplant for ESRD 7 months earlier with resultant immunosuppressive therapy. MRI and nasal biopsy confirmed rhinoorbitocerebral mucormycosis. Immunosuppressive therapy was stopped and antifungal therapy begun. He had orbital exenteration for progressive rhinoorbitocerebral mucormycosis. Two months later, the patient reported new-onset intermittent bitemporal headache and bilateral swollen, tender temporal arteries. Temporal artery biopsy revealed features consistent with calciphylaxis. Clinical presentation, treatment course, and follow up are discussed.

The authors describe a 20-year-old man who sustained multiple facial fractures in a high-speed motor vehicle crash, including a bone fragment from a skull base fracture that penetrated the orbital soft tissues superomedially. Serial CT scans documented spontaneous resorption over a 6-month period. While it is known that autologous bone grafts used in craniofacial reconstruction exhibit variable amounts of bone resorption, the complete resorption of an intraorbital fracture fragment has not been documented in the literature. His clinical care and the report of his case were undertaken in a fashion in accordance with the principles of the Health Insurance Portability and Accountability Act regulations.

Lipogranulomas of the periocular tissues with fulminant fibrotic and lymphohistiocytic responses were initially described in cases of exogenous paraffin or petrolatum jelly injections ("paraffinomas"). A 49-year-old Cambodian woman slowly developed bilateral pseudoptosis with intact levator function and redundant, taut upper eyelid skin. At surgery, vesiculations or "bubbles" in the preaponeurotic fat were encountered and were demonstrated histopathologically to be empty locules surrounded by a thin collagenous lamina. Outside these extracellular spaces were CD68/CD163-positive mononucleated and univacuolated histiocytes simulating damaged fat cells or neoplastic lipoblasts in hematoxylin and eosin sections. Giant cells and chronic sclerosing inflammation were absent. The patient denied any previous injections. The bland character of the lipogranulomas in comparison with that of other injectable agents, the absence of any residual particles associated with other cosmetic fillers, and the distinctive histiocytic response of lipoblast-like cells that were sufficiently characteristic to compel the diagnosis of surreptitious silicone injections. Other conditions were excluded based on comparative clinicopathologic criteria.

We determined whether binocular central scotomas above or below the preferred retinal locus affect detection of hazards (pedestrians) approaching from the side. Seven participants with central field loss (CFL), and seven age-and sex-matched controls with normal vision (NV), each completed two sessions of 5 test drives (each approximately 10 minutes long) in a driving simulator. Participants pressed the horn when detecting pedestrians that appeared at one of four eccentricities (-14°, -4°, left, 4°, or 14°, right, relative to car heading). Pedestrians walked or ran towards the travel lane on a collision course with the participant's vehicle, thus remaining in the same area of the visual field, assuming participant's steady forward gaze down the travel lane. Detection rates were nearly 100% for all participants. CFL participant reaction times were longer (median 2.27s, 95% CI 2.13 to 2.47) than NVs (median 1.17s, 95%CI 1.10 to 2.13; difference p<0.01), and CFL participants would have been unable to stop for 21% of pedestrians, compared with 3% for NV, p<0.001. Although the scotomas were not expected to obscure pedestrian hazards, gaze tracking revealed that scotomas did sometimes interfere with detection; late reactions usually occurred when pedestrians were entirely or partially obscured by the scotoma (time obscured correlated with reaction times, r = 0.57, p<0.001). We previously showed that scotomas lateral to the preferred retinal locus delay reaction times to a greater extent; however, taken together, the results of our studies suggest that any binocular CFL might negatively impact timely hazard detection while driving and should be a consideration when evaluating vision for driving.