Faculty Bibliography

HISTORY/METHODS:A 15-year-old boy presented to the emergency department with intractable epistaxis. He had a prior history of epistaxis typically lasting 5-10 minutes and consisting of up to four episodes per year for several years. Otherwise, the patient had no relevant medical history, and he denied having prior trauma, surgery, bleeding diathesis, fever, chills, or vision changes. Likewise, the patient had no relevant family history. The patient's coagulation panel was unremarkable and included a prothrombin time of 15.4 seconds, an international normalized ratio of 1.2, and a partial thromboplastin time of 29.3 seconds. A thin-section unenhanced sinus computed tomography (CT) examination was performed. In addition, magnetic resonance (MR) imaging of the sinuses without and with intravenous contrast material was performed. The epistaxis was treated with nasal packing, which prevented further bleeding. Biopsy of the lesion was subsequently performed.

The first part of this review of the temporal bone discussed anatomy of the temporal bone as well as inflammatory and neoplastic processes in the temporal bone region (1). This second part will first discuss trauma to the temporal bone and posttraumatic complications. The indications for common surgical procedures performed in the temporal bone and their postoperative imaging appearance are then presented. Finally, a few noninflammatory nonneoplastic entities involving the temporal bone are reviewed. They are relatively uncommon diagnoses compared with infectious or inflammatory diseases. However, because patients present with symptoms that are either common (hearing loss) or distinctive (sensorineural hearing loss in a child), they are important for the radiologist to be aware of and recognize.

The early detection and specific diagnosis of viral infections of the central nervous system are important because many of these diseases are potentially treatable. However, clinical symptoms and physical examination are often nonspecific, and rapid diagnostic tests are available for some, but not all, viruses. Neuroimaging, in conjunction with clinical history and laboratory tests, plays an important role in narrowing the differential diagnoses. In this article, we review the clinical features, imaging characteristics, diagnosis, and treatment of the more common viral infections and prions that involve the central nervous system.

OBJECTIVE:Until now, the use of computed tomography (CT) in the diagnosis and evaluation of otosclerosis has been based on correlation of radiologic findings to patient histories, intraoperative examinations, and audiologic data. The purpose of this study was to compare CT findings in otosclerosis to histopathology. STUDY DESIGN/METHODS:Prospective blinded. SETTING/METHODS:Radiology department in a tertiary referral hospital and otopathology laboratory. PATIENTS/METHODS:Temporal bones from patients with otosclerosis and other otologic diseases (used as controls). INTERVENTION(S)/METHODS:Blinded review of specimen CT scans by radiologists and comparison of CT findings to histopathology of the same bones. MAIN OUTCOME MEASURE(S)/METHODS:Ability of CT to diagnose otosclerosis, identify otosclerotic foci in defined zones of the otic capsule, determine endosteal layer involvement, oval window (OW) obliteration, and round window (RW) obliteration. RESULTS:In a randomized blinded evaluation, radiologists identified 8 of 10 bones with otosclerosis and made 3 false-positive diagnoses from the 36 control bones. Radiologic examination correctly identified otosclerosis anterior to the oval window, in the pericochlear area, and in the round window niche in 17 of 17, 9 of 11, and 3 of 6 bones, respectively. CT correctly determined involvement of the endosteal layer, OW obliteration, and RW obliteration in 5 of 8, 2 of 2, and 2 of 2 temporal bones. CONCLUSION/CONCLUSIONS:High-resolution CT is highly sensitive and specific for the diagnosis of otosclerosis when compared with histopathology. Very small and subtle otosclerotic foci seen on pathology may be missed on CT. Although CT was able to positively identify cochlear endosteal margin involvement, the false-negative rate on CT was significant.

PURPOSE/OBJECTIVE:Immunoglobin G4 (IgG4)-related disease is a systemic condition characterized by lymphoplasmacytic infiltrates that can involve the orbit. The purpose of this study was to identify the various patterns of orbital IgG4-related disease on imaging. METHODS:Retrospective review of radiologic examinations including CT, MRI, and positron emission tomography was performed in patients with proven cases of IgG4-related disease. RESULTS:A total of 9 patients with orbital IgG4-related disease were identified, including 9 with CT, 4 with MRI, and 4 with 18-fluorodeoxyglucose positron emission tomography. Patterns of involvement included lacrimal gland enlargement, lacrimal sac involvement, extraocular muscle thickening, preseptal involvement, orbital fat involvement, and cranial nerve involvement, many of which occurred simultaneously. Associated demineralization of the orbital wall was evident on CT in 2 cases. On T2-weighted MRI, the lesions appeared as hypointense in 2 cases, heterogeneously hypointense to isointense in 1 case, and hyperintense in 1 case. Diffuse enhancement was present in all 3 cases in which postcontrast T1-weighted sequences were available. The lesions were hypermetabolic on positron emission tomography in 3 of 4 cases. There was definite extraorbital involvement by IgG4-related disease in 3 of the 9 patients and suspected involvement in another 3 of the 9 patients. CONCLUSIONS:IgG4-related disease displays a wide variety of imaging manifestations in the orbit. Extraorbital disease is often present and can help suggest the diagnosis.

Neurogenic compromise of vocal fold function exists along a continuum encompassing vocal cord hypomobility (paresis) to vocal fold immobility (paralysis) with varying degrees and patterns of reinnervation. Vocal fold paralysis (VFP) may result from injury to the vagus or the recurrent laryngeal nerves anywhere along their course from the brainstem to the larynx. In this article, we review the anatomy of the vagus and recurrent laryngeal nerves and examine the various etiologies of VFP. Selected cases are presented with discussion of key imaging features of VFP including radiologic findings specific to central vagal neuropathy and peripheral recurrent nerve paralysis.

Acute ischemic stroke imaging is one of the leading causes of death and disability worldwide. Neuroimaging plays a crucial role in early diagnosis and yields essential information regarding tissue integrity, a factor that remains a key therapeutic determinant. Given the widespread public health implications of stroke and central role of neuroimaging in overall management, acute stroke imaging remains a heavily debated, extensively researched, and rapidly evolving subject. There has been recent debate in the scientific community due to divided opinions on the use of CT perfusion and access-related limitations of MRI. In this paper we review and summarize recent updates relevant to acute stroke imaging and propose an imaging paradigm based on the recently available evidence.