Faculty Bibliography

A 47 year-old female with lymphangioleiomyomatosis developed right periorbital pain worsened while chewing, six months prior. Neuroimaging demonstrated a heterogenous inferotemporal right orbital mass extending through the inferior orbital fissure into the temporalis fossa, with flow voids. Given the patient's past medical history, the lesion was presumed to be a perivascular epithelioid cell tumor, a manifestation of lymphangioleiomyomatosis. A lateral orbitotomy revealed a well-circumscribed bluish-red lesion with areas of hemorrhage that was resected in total. Histopathology, however, was consistent with a thrombosed orbital arteriovenous malformation likely arising from the zygomaticotemporal neurovascular bundle. Lymphangioleiomyomatosis is a rare progressive disease that causes cystic destruction of the lungs and is frequently associated with extrapulmonary tumor infiltration, typically of the kidney and liver. Lymphangiomyoleiomyomatosis cell pathogenesis includes a pro-angiogenic micro-environment, classically expressing vascular endothelial factor-C and -D, which we postulate may have contributed to the development of the orbital arteriovenous malformation.

PURPOSE/OBJECTIVE:To measure orbital cavernous hemangioma size using 3 segmentation methods requiring different degrees of subjective judgment, and to evaluate interobserver agreement using these methods. METHODS:Fourteen patients with orbital cavernous hemangiomas were included in the study. Pretreatment T2-weighted MRIs were analyzed by 2 observers using 3 methods, including 1 user-dependent image segmentation method that required high degrees of subjective judgment (ellipsoid) and 2 parameter-dependent methods that required low degree of subjective judgment (GrowCut and k-means clustering segmentation). Interobserver agreement was assessed using Lin's concordance correlation coefficients. RESULTS:Using the ellipsoid method, the average tumor sizes calculated by the 2 observers were 1.68 ml (standard deviation [SD] 1.45 ml) and 1.48 ml (SD 1.19 ml). Using the GrowCut method, the average tumor sizes calculated by the 2 observers were 3.00 ml (SD 2.46 ml) and 6.34 ml (SD 3.78 ml). Using k-means clustering segmentation, the average tumor sizes calculated by the 2 observers were 2.31 ml (SD 1.83 ml) and 2.12 ml (SD 1.87 ml). The concordance correlation coefficient for the ellipsoid, GrowCut, and k-means clustering methods were 0.92 (95% CI, 0.83-0.99), 0.12 (95% CI, -0.21 to 0.44), and 0.95 (95% CI, 0.90-0.99), respectively. CONCLUSIONS:k-means clustering, a parameter-dependent method with low degree of subjective judgment, showed better interobserver agreement compared with the ellipsoid and GrowCut methods. k-means clustering clearly delineated tumor boundaries and outlined components of the tumor with different signal intensities.

Purpose/UNASSIGNED:We report a case a pediatric patient with an eyelid lesion found to be a basaloid follicular hamartoma. Observations/UNASSIGNED:A six-year-old female with juvenile diabetes who presented with a benign eyelid lesion harboring an aberrant eyelash. Conclusions and Importance/UNASSIGNED:Basaloid follicular hamartoma is a rare benign neoplasm arising from hair follicles. These lesions can resemble basal cell carcinomas and require complete excision.

Purpose/UNASSIGNED:Few studies have evaluated the methodology by which radiation therapy (RT) for thyroid eye disease and compressive optic neuropathy is performed. The objective of this study was to retrospectively review our experience from a radiation planning standpoint and to determine whether current treatment methods provide adequate dose to target and collateral structures. Methods/UNASSIGNED:A retrospective review of 52 patients (104 orbits) with bilateral thyroid eye disease and compressive optic neuropathy treated with RT (20 Gy in 10 fractions) at our institution. RT plans were analyzed for target volumes and doses. Visual fields, color plates, and visual acuity were assessed pretreatment and at last available follow-up post RT. A standardized, anatomic contour of the retro-orbital space was applied to these retrospective plans to determine dose to the entire space, rather than the self-selected target structure. Results/UNASSIGNED:= .62), based on these dose differences. When beam placement was retrospectively adjusted to include a space of 0.5 cm between the lens and the anterior beam edge, there was a 39.4% and 20.3% decrease in max and mean dose to the lens. Conclusions/UNASSIGNED:Without a standardized protocol for contouring in thyroid eye disease, target delineation was found to be rather varied, even among the same practitioner. Differences in dose to the anatomic retro-orbital space did not affect outcomes in the follow-up period. Although precise contouring of the retro-orbital space may be of little clinical consequence overall, a >0.5 cm space from the lens may significantly reduce or delay cataractogenesis.

Indolent lymphomas have the potential to transform into more aggressive phenotypes. This phenomenon is best exemplified by the transformation of chronic lymphocytic leukemia/small lymphocytic lymphoma into diffuse large B-cell lymphoma. However, it is less common to find multiple small cell lymphomas in the orbit, particularly mantle cell lymphoma. We present a case of an extranodal marginal zone lymphoma arising in the orbit that acquired a subclonal t(11;14) (q13;32) CCND1-IGH translocation, giving rise to a subclone of mantle cell lymphoma. The management of this tumor was targeted towards the more aggressive mantle cell subclone. The tumor exhibited an incomplete response to rituximab alone. To the best of the authors' knowledge, this represents the first such case to be described irrespective of site of origin.

Purpose: We describe a novel surgical approach for bilateral orbital roof decompression using a frontal osteoplastic flap without frontal sinus obliteration. This technique utilizes a combined external and endonasal endoscopic approach for wide exposure to the orbital roof bilaterally. We demonstrate this technique for the resection of a massive frontal fibrous dysplasia lesion in a healthy male with bilateral orbital roof involvement. The endonasal endoscopic portion of the technique includes a Draf III frontal sinusotomy (endoscopic modified Lothrop procedure) which precludes the need for frontal sinus obliteration, restores normal frontal sinus function, and allows for postoperative endoscopic surveillance.Methods: Report of novel surgical technique with video demonstration.Results: This technique for orbital roof decompression allows for removal of a frontal lesion, wide decompression of the bilateral orbital roof, and post-operative endonasal endoscopic surveillance of the cavity. The patient in whom we demonstrate this technique had complete resolution of his orbital symptoms and minimal residual fibrous dysplasia postoperatively.Conclusion: Bilateral orbital roof decompression for frontal lesions can be performed safely and effectively with a frontal osteoplastic flap without frontal sinus obliteration, restoring normal orbital and sinus function.

Purpose: The majority of pediatric patients with optic nerve gliomas (ONG) remain asymptomatic; however, a subset of patients suffer rapid, irreversible visual loss. The purpose of this study was to determine anatomic differences of ONG noted either by imaging or by intra-operative observation between patients with gradual visual dysfunction and those with rapid visual loss.Methods: A retrospective review was performed in patients with visual loss secondary to ONG. The clinical records, pathology, and radiographic images were reviewed for all patients. The degree of folding or plication of the optic nerve (ON) was determined by analyzing the most acute angle present in the course of the ON.Outcome measures: The primary outcome measure was the angle of plication or folding of the ON and the relationship of this to the course of visual dysfunction.Results: Six patients with ONG were included in the study. A structural difference in the ON was identified in four patients with rapid vision loss compared with two patients with more gradual visual dysfunction. In patients with rapid progressive visual loss, the ONG had a 90-degree or more acute plication of the ON. Those with more gradual visual loss had more obtuse bends in the ONG.Conclusions: We have identified that the intrinsic structure of the ONG may contribute to the rare but devastatingly rapid progression of visual dysfunction in some patients. Recognizing these changes may guide clinicians to intervene prior to the development of irreversible visual loss.