American Journal of Roentgenology Head and Neck Imaging

[Head and Neck Imaging] Usefulness of Laryngeal Phonation CT in the Diagnosis of Vocal Cord Paralysis

Kim, B. S., Ahn, K. J., Park, Y. H., Hahn, S. T. — 2008-04-22

OBJECTIVE. The purpose of this study was to determine the effectiveness of laryngeal phonation CT for the diagnosis of vocal cord paralysis by examining the physiologic and functional changes in the larynx during vowel phonation in patients with vocal cord paralysis.

SUBJECTS AND METHODS. For the control study, three healthy volunteers underwent laryngeal phonation CT while vocalizing the vowels /hee/, /ih/, and /ah/, and reconstructed coronal images of the larynx were obtained. After the control study, 28 patients with unilateral vocal cord paralysis underwent laryngeal phonation CT during /hee/ phonation, which was chosen as a most appropriate vowel for this purpose. Changes in the paralyzed and normal vocal cords were evaluated quantitatively and qualitatively on coronal reconstruction images.

RESULTS. On the coronal reconstructed images from the healthy volunteers, the normal cords had a shoulder formation appearance, and the cords lay within 1 mm lateral to the midline during phonation. For patients with vocal cord paralysis during /hee/ phonation, the average angle formed by the long axis of the vocal cord and the midline was 71.67° on the affected side and 92.21° on the normal side (p = 0.001). The vocal cord edges lay 1.5 mm lateral to the midline on the affected side and 0.44 mm lateral to the midline on the normal side (p = 0.003). In the qualitative study, the two observers found the coronal reconstructions of the laryngeal phonation CT scans yielded a higher detection rate than did conventional axial CT.

CONCLUSION. Laryngeal phonation CT proved more useful for evaluating vocal cord paralysis than did conventional CT and can be used as a primary diagnostic tool when vocal cord paralysis is suspected.

[Head and Neck Imaging] MRI of Mandibular Osteonecrosis Secondary to Bisphosphonates

2008-03-20

OBJECTIVE. Bisphosphonates are a group of drugs used in the treatment of oncology patients with bone metastases. However, in the past few years, osteonecrosis of the jaw has been reported as a serious complication of such treatment. The objective of this study was to examine the use of MRI in the assessment of bone lesions caused by this disease.

MATERIALS AND METHODS. Fourteen patients were studied who had been treated with IV bisphosphonates and had developed focal lesions of osteonecrosis of the jaw. These patients were referred by the stomatology department of Hospital General Universitario de Valencia. We evaluated both the morphology and the behavior of the lesions in T1, STIR, and after the administration of gadolinium.

RESULTS. Twenty-six focal lesions were detected clinically and 36 were detected radiologically. All the clinically detected focal lesions were visible on MRI. There were 15 focal lesions detected radiologically that were not detected on clinical examination. In all patients, it was possible to assess bone involvement and involvement of the bone marrow, soft tissues, sinuses, and mandibular canal as well as the presence of adenopathy.

CONCLUSION. MRI is an effective tool in the assessment of osteonecrosis of the jaw. The significance of focal lesions detectable on radiologic examination but without clinical correlation and their progression over time remains to be determined.

[Head and Neck Imaging] Orbital Lesions: Differentiating Vascular and Nonvascular Etiologic Factors

Poon, C. S., Sze, G., Johnson, M. H. — 2008-03-20

OBJECTIVE. Using a number of interesting cases, we illustrate how attention to vascular anatomic features and blood flow patterns can facilitate the diagnosis of an orbital lesion. True vascular lesions can be differentiated from nonvascular mimics, and normal variants of the orbital blood flow pattern can be differentiated from pathologic alterations.

CONCLUSION. Accuracy of radiologic diagnosis can be improved by an understanding of orbital vascular anatomy and blood flow patterns and with optimal use of imaging techniques.

[Head and Neck Imaging] Fluoroscopic Intralesional Injection with Pingyangmycin Lipiodol Emulsion for the Treatment of Orbital Venous Malformations

Chen, Y., Li, Y., Zhu, Q., Zeng, Q., Zhao, J., He, X., Mei, Q. — 2008-03-20

OBJECTIVE. The objective of our study was to evaluate the efficacy and safety of percutaneous intralesional injection under fluoroscopy with pingyangmycin Lipiodol emulsion (PLE) for the treatment of orbital venous malformations.

MATERIALS AND METHODS. This study is a retrospective analysis of 19 consecutive patients with distensible orbital venous malformations. Of the 19 patients, two had diffuse lesions. These patients presented with proptosis (n = 19), pain and orbital swelling (n = 11), reduction in visual acuity (n = 4), diplopia (n = 2), disk swelling (n = 5), and motility disturbance (n = 3).

RESULTS. All 19 patients underwent technically successful percutaneous intralesional PLE injection under fluoroscopy. Complete resolution of proptosis, swelling, and pain was achieved in 17 patients 3–9 months after the procedure. In the other two patients with diffuse lesions, light proptosis was still present after the first procedure. A second procedure was performed in these two patients, and the symptom disappeared 3 months later. All four patients with reduced visual acuity recovered their vision, and diplopia in two patients disappeared. Examinations of the fundus revealed normal findings in the five patients with preprocedural disk swelling. None of the patients presented with a motility disturbance after the procedure. Local swelling in the eyelid and epiphora were present for 1 month in one patient and disappeared after treatment. No other complications, including acute orbital compartment syndrome, were observed during follow-up periods. The mean follow-up was 23 months.

CONCLUSION. PLE sclerotherapy under fluoroscopic guidance is safe and effective for the treatment of orbital venous malformations and can be used as one of the treatment alternatives.

[Head and Neck Imaging] Hypervascular Thyroid Nodules on Time-Resolved MR Angiography at 3 T: Radiologic-Pathologic Correlation

Lohan, D. G., Tomasian, A., Saleh, R., Krishnam, M., Finn, J. P. — 2008-03-20

OBJECTIVE. Detection of a thyroid nodule, either incidental or as a result of related symptomatology, is an extremely common event, often inducing considerable uncertainty regarding the requirement for and best means of further investigation. Whereas tissue sampling represents the sole means of true characterization of these lesions, a number of imaging characteristics have been suggested as potential indicators of the presence of malignancy. The potential value of time-resolved MR angiography, whereby a minimal dose of IV contrast agent is dynamically depicted during the first pass of the bolus through the various compartments of circulation, has recently been realized, particularly so with regard to supraaortic angiography. However, it is not uncommon during such temporal imaging to identify focal hyperenhancing thyroid nodules, the significance of which has not previously been described in the literature. We describe the frequency of occurrence and potential significance of this finding, using pathologic correlation where available.

CONCLUSION. The prevalence of malignancy in incidentally detected focal hyperenhancing thyroid parenchymal nodules during time-resolved MR angiography is significant, representing 8.3% (1/12) of patients for whom cytologic correlation was available. Further investigation is certainly warranted when encountering such a lesion in clinical practice, particularly because it appears as though time-resolved MR angiography is of no value in the pathologic discrimination of such incidentally identified lesions.