Mary Beth Cunnane

Patterns of Perineural Tumor Spread in Head and Neck Cancer

Perineural tumor spread (PNS) is a mode of neoplastic spread whereby tumor cells use neural conduits to escape the borders of a primary tumor. MRI is generally favored over CT for evaluating PNS, and findings include obliteration of fat within skull base foramina, enlargement and enhancement of the involved nerves, and enlargement and destruction of the bony foramina. Careful examination of the entire course of the nerve allows detection of skip lesions. Recognition of the complete extent of PNS is crucial for correct treatment because it facilitates both surgical and radiotherapy targeting of entire extent of disease.

The Use of Diffusion MRI in Ischemic Optic Neuropathy and Optic Neuritis

Ischemic optic neuropathy and optic neuritis are the most common causes of unilateral non-glaucomatous visual loss. While they have distinctive clinical features, they also share some overlapping profiles that make it difficult to clinically distinguish these two entities. MRI with gadolinium has been proven to be helpful to confirm the diagnosis of optic neuritis, but ischemic optic neuropathy remains a clinical diagnosis. Diffusion MRI, a newly advanced technique, has been used in studying the pathophysiology of optic neuritis, but its use in ischemic optic neuropathy is limited. Diffuse MRI may potentially be of help to diagnose ischemic optic neuropathy.

Direct parasagittal magnetic resonance imaging of the internal auditory canal to determine cochlear or auditory brainstem implant candidacy in children

Laryngoscope, 125:2382–2385, 2015

Vascular Compression of the Airway: Establishing a Functional Diagnostic Algorithm

IMPORTANCE Pediatric imaging carries the risk of radiation exposure. Children frequently undergo computed tomography with angiography (CTA) for findings on bronchoscopy with limited knowledge regarding the necessity of such imaging. OBJECTIVE To report our experience with all pediatric patients at our institution over an 8-year period with airway symptoms warranting bronchoscopy followed by CTA for potential vascular anomaly. Goals were to report the percentage of positive findings seen on CTA leading to surgery; discuss relative radiation exposure risk and sedation risk for additional radiologic studies; and propose a functional diagnostic algorithm. DESIGN, SETTING, AND PARTICIPANTS Retrospective chart review of 42 children aged 2 months to 11 years with tracheomalacia who underwent CTA between 2004 and 2012 in our tertiary aerodigestive center. INTERVENTIONS Bronchoscopy and CTA. MAIN OUTCOMES AND MEASURES Presence of vascular anomaly and need for thoracic surgery. RESULTS Of these 42 children, 21 (50%) had a vascular anomaly identified on CTA. Of these 21, 17 (81%) had innominate artery compression; 1 (5%) had double aortic arch; 1 (5%) had right aortic arch; 3 (14%) had bronchial compression by pulmonary artery; and 1 (5%) had dextrocardia with duplicated vena cava. Six (29%) of these 21 had clinical symptoms and CTA findings requiring thoracic surgery. The most common symptoms in children requiring thoracic surgery were cough, cyanosis, and stridor. CONCLUSIONS AND RELEVANCE Deciding when to obtain imaging for bronchoscopic findings suggestive of vascular compression remains challenging. A diagnostic algorithm is proposed as a means to provide the best clinical care while weighing risks of additional radiation exposure vs sedation and exposure to general anesthesia.

Losing Your Voice: Etiologies and Imaging Features of Vocal Fold Paralysis

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.

Imaging of orbital disorders.

Diseases of the orbit can be categorized in many ways, but in this chapter we shall group them according to etiology. Inflammatory diseases of the orbits may be infectious or noninfectious. Of the infections, orbital cellulitis is the most common and typically arises as a complication of acute sinusitis. Of the noninfectious, inflammatory conditions, thyroid orbitopathy is the most common and results in enlargement of the extraocular muscles and proliferation of the orbital fat. Idiopathic orbital inflammatory syndrome is another cause of inflammation in the orbit, which may mimic thyroid orbitopathy or even neoplasm, but typically presents with pain. Masses in the orbit may be benign or malignant and the differential diagnosis primarily depends on the location of the mass lesion, and on the age of the patient. Lacrimal gland tumors may be lymphomas or epithelial lesions of salivary origin. Extraocular muscle tumors may represent lymphoma or metastases. Tumors of the intraconal fat are often benign, typically hemangiomas or schwannomas. Finally, globe tumors may be retinoblastomas (in children), or choroidal melanomas or metastases in adults.

Finding a Voice: Imaging Features after Phonosurgical Procedures for Vocal Fold Paralysis.

SUMMARY: Altered communication (hoarseness, dysphonia, and breathy voice) that can result from vocal fold paralysis, secondary to numerous etiologies, may be amenable to surgical restoration. In this article, both traditional and cutting-edge phonosurgical procedures targeting the symptoms resulting from vocal fold paralysis are reviewed, with emphasis on the characteristic imaging appearances of various injectable materials, implants, and augmentation procedures used in the treatment of vocal fold paralysis. In addition, complications of injection laryngoplasty and medialization laryngoplasty are illustrated. Familiarity with the expected imaging changes following treatment of vocal fold paralysis may prevent the misinterpretation of posttreatment changes as pathology. Identifying common complications related to injection laryngoplasty and localization of displaced implants is crucial in determining specific management in patients who have undergone phonosurgical procedures for the management of vocal fold paralysis.

MR imaging findings of endophthalmitis.

Endophthalmitis is a sight-threatening ophthalmologic emergency. The clinical diagnosis is often challenging, and delayed diagnosis may exacerbate the poor visual prognosis. B-scan ultrasonography or spectral domain optical coherence tomography are imaging aids at the clinician’s office. Cross-sectional imaging such as CT and particularly MRI can also help in the assessment of disease extent or complications. MR imaging findings are rarely described in the literature. Here, we discuss the spectrum of imaging findings of endophthalmitis and correlate them with key anatomic and pathophysiologic details of the globe. Early disease is often subtle on MR imaging with thick uveal enhancement, while advanced disease demonstrates retinal/choroidal detachment, vitreal exudates and peribulbar inflammation. Other noninfectious inflammatory diseases of the globe can show similar findings; however, MR diffusion-weighted images help identify infectious exudates and evaluate response to therapy. Knowledge of the spectrum of imaging findings of this disease is important for radiologists and help in the management decision process.

Noncontrast vestibular schwannoma surveillance imaging including an MR cisternographic sequence: is there a need for postcontrast imaging?

OBJECTIVEThe purpose of this study was to evaluate the use of a noncontrast MRI protocol that includes a cisternographic sequence (CISS/FIESTA/3D DRIVE) compared to a protocol that includes a gadolinium-enhanced sequence in order to determine whether a noncontrast approach could be utilized to follow vestibular schwannomas.METHODSA total of 251 patients with vestibular schwannomas who underwent MRI of the temporal bones that included both cisternographic sequence and postcontrast T1 imaging between January 2000 and January 2016 for surveillance were included in this retrospective study. The size of the vestibular schwannomas was independently assessed on a noncontrast MR cisternographic sequence and compared to size measurements on a postcontrast sequence. The evaluation of intralesional cystic components (identified as T2 signal hyperintensity) and hemorrhagic components (identified with intrinsic T1 hyperintensity) on noncontrast MR sequences was compared to evaluation on postcontrast MR sequences to determine whether additional information could be derived from the postcontrast sequences. Additionally, any potentially clinically significant, incidentally detected findings on the postcontrast T1 sequences were documented and compared with the detection of these findings on the precontrast images.RESULTSNo significant difference in vestibular schwannoma size was found when comparing measurements made on the images obtained with the MR cisternographic sequence and those made on images obtained with the postcontrast sequence (p = 0.99). Noncontrast MR images were better (detection rate of 87%) than postcontrast images for detection of cystic components. Noncontrast MR images were also better for identifying hemorrhagic components. No additional clinically relevant information regarding the tumors was identified on the postcontrast sequences.CONCLUSIONSBased on the results of this study, a noncontrast MR protocol that includes a cisternographic sequence would be sufficient for the accurate characterization of size and signal characteristics of vestibular schwannomas, obviating the need for gadolinium contrast administration for the routine surveillance of these lesions.

Laryngeal mask airway may result in false negative imaging for carotid medialization: A case report.

Chromosome 22q11.2 microdeletions result in multiple congenital abnormalities, including an increased risk of carotid medialization, which is an important consideration for preoperative planning in children with velopharyngeal insufficiency. Preoperative imaging of the neck vasculature is recommended. Here we describe a case in which a child had negative imaging studies despite the presence of a medialized carotid artery on physical examination, likely secondary to the supraglottic airway use during sedated imaging, which displaced the carotid laterally. The type of airway used should be a consideration for children undergoing sedated imaging prior to pharyngeal procedures.