Differential Diagnoses of Diseases Involving the Extrinsic Ocular Musculature – A Pictorial Essay

Introduction There are some inflammatory, infectious, and neoplastic diseases affecting the extrinsic orbital musculature (EOM) that present with pain, decreased visual acuity, and proptosis. Imaging is fundamental to the differential diagnoses of these diseases with similar clinical presentations. The present case series report has as main objective to illustrate and discuss the main pathologies that affect the orbit. Material and methods The present series of cases discusses the main pathologies that can affect the extraocular musculature that can be characterized by computed tomography (CT) or magnetic resonance imaging (MRI) using cases from our institution. Results and Discussion The present study compiled several cases of ophthalmopathy from our institution to illustrate and address some of these pathologies, such as orbital lymphoma, Grave disease, metastases, periorbital cellulitis, and idiopathic orbital inflammatory syndrome. The diseases are discussed according to the presentation of clinical cases with emphasis on the main imaging findings of each pathology. Conclusion Computed tomography and MRI can help in the diagnosis and follow-up of the diseases that affect the EOM. We must be conversant with the main characteristics of the pathologies presented in the present case series report, since such findings together with clinical data can confirm the diagnosis of these diseases or at least help to narrow the differential diagnoses.

Clipping of Multiple Cerebral Aneurysms Through Cranioorbital Zygomatic Approach: 2-Dimensional Operative Video

Ruptured cerebral aneurysm is a grave disease, with a high morbidity and mortality, mandating securing the aneurysm to eliminate fatal rebleeding.1 Multiple aneurysms are frequent and may occur in approximately 20% of the cases with female prominence.2 The risk of subarachnoid hemorrhage in unruptured aneurysms is higher in patients who had prior ruptured aneurysms.3 Hence, there is an indication of treating all concomitant aneurysms when one is ruptured. We present the case of clipping of 3 aneurysms via a cranioobritozygomatic (COZ) approach including a middle cerebral artery, anterior choroidal artery, and superior cerebellar artery in a patient presenting with subarachnoid hemorrhage and multiple aneurysms with suboptimal morphology for endovascular coiling. We highlight the advantages of the COZ in the clipping of complex posterior circulation aneurysms and the advantage of mobilization of neural structures to gain wider exposure.4-6 The temporal fossa space provided by zygomatic osteotomy allows the outward mobilization of the temporal lobe after freeing it by splitting the Sylvian fissure. The falciform ligament is opened overlying the optic nerve, allowing for safe dissection within the opticocarotid window. The oculomotor nerve is detethered from the dura surrounding its entry into the cavernous sinus. These maneuvers allow for mobilization of the critical neurovascular structures, which widens the operative corridor without undue traction or retraction. The COZ with clinoidectomy shortens and widens the operative field, allows for enhanced maneuverability, improved visualization, and exposure of the clinoidal carotid, and facilitates the release and mobilization of the optic and third nerve. The patient consented to surgery. Image at 1:40 reprinted with permission from Al-Mefty O, Operative Atlas of Meningiomas. Vol 1, © LWW, 1998.

1552. Clinical Outcomes and Healthcare Costs of Inpatients with Tetanus in Korea in 2011–2019

Background We aimed to investigate the recent trend of clinical outcomes and medical costs of inpatients with tetanus, which is a rare, vaccine-preventable but extremely grave disease, in Korea, in 2011–2019 for the first time. Methods From January 2011 to October 2019, this study examined 49 patients with tetanus admitted in 2 national university hospitals in Gwangju and Daegu of South Korea. Patients’ medical records were retrospectively reviewed to determine the clinical factors and medical cost for tetanus management. Results The mean age was 65.3 ± 16.1 years and 32 (65.3%) of them were female. All patients (100.0%) had generalized tetanus, and 5 (10.2%) died during admission. The median duration from symptom onset to hospital visit was 4 days. Trismus (85.7%) was the most common symptom, and wound of the lower extremities (24.5%) was the most frequent presumed entry site of toxin. Only 6 (15.0%) patients were operated for wound management. The median hospital stay was 39 (9; 49) days. Furthermore, 32 (65.3%) needed mechanical ventilation, and 20 (40.8%) patients developed aspiration pneumonia. The median total healthcare cost was 21,072 KRW(Korean Republic Won) (17,560 USD(United States Dollar); 1 USD = 1200 KRW) per person. After discharge, 35 (79.5%) patients fully recovered without any disability. Conclusion Tetanus remains a grave disease that requires long duration of admission and huge medical cost in Korea. The completion rate of 3-time tetanus toxoid (Td) or tetanus toxoid, acellular pertussis and diphtheria vaccine (Tdap) vaccination was low; thus, the medical staff needs to establish more medical advice or policies to the general population of Korea Disclosures All Authors: No reported disclosures

Lipomatous Metaplasia of the Thyroid Gland: A Clinicopathologic Review

Objectives Lipomatous metaplasia involving the thyroid gland is uncommon in surgical pathology and the majority of published literature is confined to single case reports. We undertook a retrospective study to assess the frequency of fat metaplasia among benign and neoplastic thyroid lesions. Methods Surgical pathology files from 1992 to 2018 at our institution were searched for lipomatous metaplasia involving the thyroid gland. A total of 2,018 cases of thyroid lesions after lobectomy or total thyroidectomy with or without regional lymph node sampling were identified. Patient clinical and pathologic data were reviewed. Results The 2,018 thyroid cases reviewed included 828 papillary carcinomas, 33 medullary carcinomas, 26 anaplastic carcinomas, 25 follicular carcinomas, 262 follicular adenomas, 422 goiters, 373 Hashimoto thyroiditis, and 49 Grave disease. Lipomatous metaplasia was recorded in 17 cases (0.8%), which included 8 males and 9 females with a mean age of 67 years (range: 55 to 82). The most common lesion containing fat metaplasia was goiter (7/422 cases, 1.7%), followed by follicular adenoma (4/262, 1.5%), papillary carcinoma (4/828, 0.5%), Hashimoto thyroiditis (1/373, 0.3%), and Grave disease (1/49, 2%). When associated with papillary carcinoma, lipomatous metaplasia was located in the surrounding benign thyroid tissue in 2/4 cases and in malignant papillary structures metastatic to neck lymph nodes in the remaining 2/4 cases. Conclusion Lipomatous metaplasia of the thyroid gland is a rare phenomenon, present in only 17/2,018 cases (0.8%) in our study. It was more commonly seen in reactive processes (9/844 cases, 1.1%) and follicular adenomas (4/262 cases, 1.5%). Among the 912 cases of malignant tumors, fat metaplasia was only identified in papillary carcinoma (4/828, 0.5%), half of which showed metaplasia at the metastatic site. The presence of lipomatous metaplasia in reactive as well as neoplastic lesions cannot be used as a reliable histologic feature to exclude a neoplastic process.