Vocal Cord Paralysis Due to Extralaryngeal Causes: Evaluation with CT1

PURPOSE: To evaluate the use of CT in patients with vocal cord paralysis due to extralaryngeal cause s ,andto use CT for the assessment of extralaryngeal diseases causing vocal cord paralysis. MATERIALS AND METHODS: Weprospectively studied the results of CT in 41 patients with vocal cord paralysis in whom laryngoscopy revealed nolaryngeal cause and physical examination demonstrated no definite extralaryngeal cause. The extralaryngeal causeof vocal cord palsy was determined after comprehensive clinical diagnosis. Enhanced CT scans were acquired fromthe skull base and continued to the level of the aorticopulmonary window. We used CT to assess the detection ratefor extralaryngeal causes and to extimate the extent of extralaryngeal disease and the distribution of lesions. RESULTS: CT revealed that in 20 of 41 patients(49%) the extralarygeal causes of vocal paralysis were as follows :thyroid cancer(n=10), nodal disease(n=6), esophageal cancer(n=2), neurogenic tumor(n=1), aortic aneurysm(n=1).Lesions were located on the left side in 13 patients(65%), and in the tracheoesophageal groove in 15(75%). CONCLUSION: In patients with vocal cord paralysis in whom no definite lesion is seen on physical examination, CT could be a useful primary imaging method for the assessment of extralaryngeal causes.

MR Imaging Findings of Fatigue Fractures of Lower Extremity in Young Soldiers

PURPOSE: To evaluate the MR imaging findings of fatigue fractures of the lower extremity in young soldiers. MATERIALS AND METHODS: In 22 cases of fatigue fractures of the lower extremity in young soldiers proven byclinical findings and radiological follow up, the MRI findings were retrospectively evalvated. All patients weremale and aged between 19 and 21 years. As seen on MRI, the bone marrow edema, intramedullary low signal intensityband, cortical fracture line, periosteal reaction, surrounding soft tissue edema, and enhancement pattern wereanalyzed and the site of involvement was determined in the axial plane. RESULTS: The locations of fatiguefractures of the lower extremity were the tibia (n=12), fibula (n=8), femur (n=1) and second metatarsus (n=1). Alloccurred in diaphyses: the junction of the proximal and middle (n=10), middle (n=9), proximal (n=2), and distalshaft (n=1). The sites of involvement were the posteromedial (n=6) and medial side (n=6) of the tibia, and theentire portion of the fibula(n=5) in the axial plane. MRI findings were bone marrow edema in 20 cases,intramedullary low signal intensity band in 14 (which were continuous with the cortex or cortical fracture line),cortical fracture line in 13, and periosteal reaction and surrounding soft tissue edema in all. Ongadolinium-enhanced images, enhancement was seen in the bone marrow in 19 cases, in the subperiosteal region in18, and in the surrounding soft tissue in 22. CONCLUSION: In fatigue fractures of the lower extremity in youngsoldiers, the main locations were the tibia and fibula, and characteristic MR imaging findings were intramedullarylow signal intensity bands, which were continuous with the cortex or cortical fracture line and often accompaniedby bone marrow edema, periosteal reaction, and surrounding soft tissue edema.

MR Imaging in Bell's Palsy and Herpes Zoster Oticus: Correlation with Clinical Findings

PURPOSE: To evaluate the MRI findings of acute facial nerve paralysis in Bell's palsy and herpes zosteroticus, and to correlate these with the clinical findings. MATERIALS AND METHODS: We retrospectively reviewed theMRI findings in six cases of Bell's palsy(BP) and two of herpes zoster oticus(HZO), and compared them with thefindings for 30 normal facial nerves. This nerve was considered abnormal when its signal intensity was greaterthan that of brain parenchyma or the contralateral normal side on Gd-enhanced T1-weighted axial and coronal MRimages. We analysed the location and degree of contrast enhancement, interval change, and clinical progression incorrelation with House-Brackmann(HB) grade and electroneuronography(ENoG) findings. RESULTS: Fifteen of 30 normalfacial nerves(50%) seen on Gd-enhanced MRI were mildly enhanced in the geniculate ganglion, the proximal tympanic,and the proximal mastoid segment of the facial nerve. No enhancement of the internal auditory canal(IAC) orlabyrinthine segment of the facial nerve was noted, however. In BP and HZO, Gd-enhanced MR images revealed fair tomarked enhancement for more than two segments from the internal auditory canal to the mastoid segment of thefacial nerve. During follow-up MRI, enhancement of the facial nerve varied in location and signal intensity,though gradually decreased in intensity approximately eight weeks after the onset of facial nerve palsy. Nocorrelation between clinical HB grade, ENoG, and follow up MRI findings was noted. CONCLUSION: Except in theinternal auditory canal and labyrinthine segment, normal facial neve may show mild and relatively symmetricalenhancement. In BP and HZO, the facial nerve showed diffuse enhancement from the IAC to the mastoid segment.