Alina Uzelac

Rosai-Dorfman Disease Isolated to the Thoracic Epidural Spine

Rosai-Dorfman disease is a rare benign histiocytic disease that infrequently presents in the spine. We report a case of Rosai-Dorfman disease isolated to the epidural thoracic spine in a 26-year-old male. To our knowledge, this is the 15th reported case of isolated spinal disease and only the fourth case of isolated thoracic epidural disease. Given its rarity as well as non-specific symptoms and imaging findings, Rosai-Dorfman disease is often not considered and misdiagnosed on imaging studies. To help improve awareness of Rosai-Dorfman spinal disease, we review the literature and discuss the epidemiology, clinical presentation, imaging features, and treatment considerations for this condition.

Earlier and more specific detection of persistent neck disease with diffusion‐weighted MRI versus subsequent PET/CT after definitive chemoradiation for oropharyngeal squamous cell carcinoma

The purpose of this study was to test if diffusion‐weighted imaging (DWI) identified persistent neck disease after chemoradiotherapy (CRT) for oropharyngeal cancer earlier and as accurately as subsequent positron emission tomography (PET)/CT.

Ex-PRESS glaucoma filter: an MRI compatible metallic orbital foreign body imaged at 1.5 and 3 T

AIM To report on the MRI compatibility of the Ex-PRESS glaucoma filtration device, a tiny metallic implant placed into the anterior chamber of the eye that is much smaller than traditional glaucoma shunts, and to educate the radiology community regarding its appearance. MATERIALS AND METHODS Seven patients with Ex-PRESS glaucoma filtration devices were identified that had undergone MRI at San Francisco General Hospital/University of California San Francisco Medical Center by searching and cross-referencing the radiology reporting system and the electronic medical record. MRI images were reviewed for artefact interfering with interpretation. Ophthalmology examinations were reviewed for evidence of complications. RESULTS Eighteen individual MRI examinations were performed during 12 unique MRI events on these 7 patients. 13/18 individual MRI examinations and 7/12 MRI events were performed at 3 T with the others performed at 1.5 T. Mean time from Ex-PRESS implantation to MRI was 17.5 months. Mean time from MRI to first ophthalmology examination was 1.1 months and from MRI to latest ophthalmology examination was 6.6 months. Susceptibility artefact did not interfere with image interpretation and no complications related to MRI were encountered. CONCLUSION The Ex-PRESS glaucoma filtration device appears to be safe for MRI at 1.5 and 3 T and does not produce significant susceptibility artefact to affect diagnostic interpretation adversely.

The advantages and drawbacks of routine magnetic resonance imaging for long-term post-treatment locoregional surveillance of oral cavity squamous cell carcinoma☆☆☆

PURPOSE Assess the clinical utility and accuracy of routine surveillance head and neck magnetic resonance imaging (HN-MRI) for the detection of locoregional recurrence in patients with a history of oral cavity squamous cell carcinoma (OCSCC) without concurrent suspicious symptoms or signs 6 months or more after treatment. MATERIALS AND METHODS For OCSCC patients who underwent routine (defined as: without concurrent suspicious symptoms or signs) surveillance HN-MRI at 6 months or more after treatment completion, we retrospectively determined the detection rate of locoregional disease and false positive rate. RESULTS Out of an original cohort of 533 OCSCC patients, 46 patients, who were disease-free 6 months after treatment, had undergone 108 routine HN-MRIs from 6 to 48 months after surgery without the presence of concurrent suspicious symptoms or signs and had 6 months of subsequent follow up. 1 out of 46 (2.2%) had a true positive regional recurrence. 10 out of 46 (21.7%) patients experienced a false positive locoregional finding. CONCLUSIONS Routine HN-MRI for locoregional surveillance of OCSCC, when used in patients without concurrent suspicious symptoms or exam findings over 6 months since treatment, may be unnecessary and costly given the very low rate of recurrence and high false positive rate. Our study supports the National Comprehensive Cancer Network guideline of limiting imaging after 6 months of primary treatment completion to patients with suspicious clinical findings. Nonetheless, managing physicians should continue to be empowered to use surveillance imaging based on risk profiles and unique circumstances for each patient.

Brain MRI Features of CSF Human Immunodeficiency Virus Escape: Brain MRI Features of CSF HIV Escape

HIV infection of the central nervous system (CNS) is a nearly universal feature of untreated systemic HIV infection. While combination antiretroviral therapy (ART) that suppresses systemic infection usually suppresses CNS (CNS) HIV infection, exceptions have been reported with discordance between CSF and blood HIV RNA concentrations such that CSF demonstrates higher HIV concentrations than blood, referred to as CSF HIV escape. Rarely, CSF HIV escape presents with neurological symptoms, called neurosymptomatic escape.

Utility of Repeat Head CT in Patients with Blunt Traumatic Brain Injury Presenting with Small Isolated Falcine or Tentorial Subdural Hematomas

BACKGROUND AND PURPOSE: In blunt traumatic brain injury with isolated falcotentorial subdural hematoma not amenable to neurosurgical intervention, the routinely performed, nonvalidated practice of serial head CT scans frequently necessitates increased hospital resources and exposure to ionizing radiation. The study goal was to evaluate clinical and imaging features of isolated falcotentorial subdural hematoma at presentation and short-term follow-up. MATERIALS AND METHODS: We performed a retrospective analysis of patients presenting to a level 1 trauma center from January 2013 to March 2015 undergoing initial and short-term follow-up CT with initial findings positive for isolated subdural hematoma along the falx and/or tentorium. Patients with penetrating trauma, other sites of intracranial hemorrhage, or depressed skull fractures were excluded. Patient sex, age, Glasgow Coma Scale score, and anticoagulation history were obtained through review of the electronic medical records. RESULTS: Eighty patients met the inclusion criteria (53 males; 27 females; median age, 61 years). Of subdural hematomas, 57.1% were falcine, 33.8% were tentorial, and 9.1% were mixed. The mean initial Glasgow Coma Scale score was 14.2 (range, 6–15). Isolated falcotentorial subdural hematomas were small (mean, 2.8 mm; range, 1–8 mm) without mass effect and significant change on follow-up CT (mean, 2.7 mm; range, 0–8 mm; P = .06), with an average follow-up time of 10.3 hours (range, 3.9–192 hours). All repeat CTs demonstrated no change or decreased size of the initial subdural hematoma. No new intracranial hemorrhages were seen on follow-up CT. CONCLUSIONS: Isolated falcotentorial subdural hematomas in blunt traumatic brain injury average 2.8 mm in thickness and do not increase in size on short-term follow-up CT. Present data suggest that repeat CT in patients with mild traumatic brain injury with isolated falcotentorial subdural hematoma may not be necessary.

The Limitations of Routine Magnetic Resonance Imaging for Long-Term Post-Treatment Locoregional Surveillance of Salivary Carcinoma

Background/Aims: To determine the utility of head and neck magnetic resonance imaging (HN-MRI) for the routine surveillance of patients without concurrent symptoms or signs of recurrence more than 6 months after treatment for salivary gland carcinoma (SGC). Methods: This is a retrospective single-institution review of SGC patients from 2000 to 2011 who underwent one or more HN-MRI scans without concurrent suspicious symptoms or signs of recurrence more than 6 months after the completion of treatment, with at least 6 months of follow-up after each scan. Results: Out of an original 283 SGC patients treated surgically, 41 patients, who were disease free 6 months after treatment, had undergone 96 routine HN-MRIs without concurrent suspicious symptoms or signs. Ten out of the 41 patients (24%) experienced a false-positive finding with routine HN-MRI. None of the 96 HN-MRIs demonstrated a true-positive or false-negative finding. Conclusion: More than 6 months after treatment, routine HN-MRI for the detection of locoregional recurrence of SGC has a low utility in patients without concurrent suspicious symptoms or signs. While these data support the judicious use of routine HN-MRIs, the managing physician should ultimately decide on the best course of surveillance for an individual patient based on the unique risk factors and circumstances present.

CNS siderosis and orthostatic headache as a delayed complication of spinal surgery

A 61-year-old man presented with orthostatic headaches and asymmetric sensorineural hearing loss (ASNHL) 8 years after cervical laminoplasty. Percussion of his cervical spine elicited Lhermitte sign. Brain MRI demonstrated trace intraventricular blood and mild superficial siderosis (figure 1); digital subtraction angiogram had normal results. CT myelogram revealed fractured hardware puncturing adjacent dura with resultant CSF leak (figure 2).