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The purpose of this study was to present the imaging features of primary and secondary malignant lacrimal sac and nasolacrimal duct tumors and their pattern of tumor spread in 18 patients. The most common tumor histology in our series was squamous cell carcinoma. In 15/18 patients, tumor involved both the lacrimal sac and duct at the time of diagnosis. In 11/16 patients on CT, the nasolacrimal bony canal was smoothly expanded without erosive changes. The medial canthus region (16/18) was a frequent site of direct tumor spread. Two patients had intraconal orbital spread of tumor. Tumor spread to the sinus or nasal cavity was observed in 5/13 primary tumors. Only 1 patient presented with nodal metastasis. There was no intracranial tumor extension, perineural tumor spread along the infraorbital nerve, distant metastasis, or dacryocystocele formation in any of the patients at the time of diagnosis.

Some of the reported neurological manifestations of COVID-19 are encephalopathy, headache, ischemic, hemorrhagic stroke, Miller Fisher syndrome, cranial neuropathies, and Guillain-Barre syndrome. We report a case of a 75-year-old COVID-19 patient with life-threatening intracranial hemorrhage. The initial labs on admission showed D-dimer of 1.04 µg/mL, which increased to 3.74 µg/mL the next day, PT/INR of 13.7 seconds/1.2, aPTT of 22 seconds, fibrinogen of 386 mg/dL, WBC of 9.71 K/µL, Hgb of 14.1 g/dL, platelet of 315 x 10 3 /µL, LDH of 965 U/L, and CRP of 35.2 mg/dL. In addition to aspirin and Plavix (clopidogrel), the patient was started on a therapeutic dose of enoxaparin due to elevated D-dimer. A few days later, the patient had a change in the neurological examination. The CT of the head without contrast revealed a left-sided acute subdural hematoma, causing left to right midline shift, a large left temporal intraparenchymal, and subarachnoid hemorrhage with transtentorial herniation, leading to death. This case illustrates a combination of factors including hypertension, triple therapy (aspirin, clopidogrel, and enoxaparin), and underlying coagulopathy due to COVID-19, which contributed to the life-threatening intracranial hemorrhage in this patient. Therefore, this raises a concern about the safety of starting these patients preemptively on a therapeutic dose of anticoagulation.

We demonstrate the conventional and advanced imaging characteristics of ETMR, including MRS and diffusion tensor imaging, which, to our knowledge, have not been systematically evaluated in the radiology literature. The knowledge gained may potentially impact patient management, especially in inoperable cases and in locations where it is risky to perform a biopsy.

Magnetic resonance (MR) venography and computed tomographic (CT) venography are suited for displaying the convexity veins that drain the medial and lateral surfaces of the brain hemispheres. However, such is not the case for the bridging veins of the skull base. Technical factors prevent contrast material-enhanced MR or CT images obtained in standard axial, coronal, and sagittal planes from fully displaying the curved pathways of these clinically important venous structures. This limitation can be overcome by using a reconstruction technique that depicts these venous structures and their interconnections. Curved and multiplanar reformatted images that distill the important venous features often require knowledgeable manipulation of source images by an operator who is familiar with numerous venous variants and their surgical implications. The normal anatomy of the draining veins is detailed-anatomy that radiologists must master before they can show the surgeon the important venous anatomy that is often missing at standard imaging; this information will foster better communication between radiologists and their surgical colleagues. As a practical matter, the skull base veins are arbitrarily subdivided into those that are at greatest risk with the pterional approach and the subtemporal approach, respectively. These approaches can be expanded to define connections between the superficial venous system and the other valveless venous networks that drain the deep portions of the cerebral hemisphere, the scalp, face, muscles of the neck, diploë of the skull, and meninges. As radiologists gain experience, their image interpretations should mature beyond simple analysis of the primary hemodynamic changes induced by intraoperative sacrifice or injury.

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