Isolated primary unilateral stenosis of the internal auditory canal.

Congenital primary stenosis of the internal auditory canal (IAC) may exist in isolation or along with a number of other osseous anomalies of the temporal bone. Most of the literature on IAC stenosis is concerned with its effect on the outcome of cochlear implantation (i.e. patients with profound bilateral hearing loss). In addition, some degree of canal asymmetry has been noted in patients with normal hearing, questioning the causal relationship of this finding to deafness. We describe two children with computed tomography (CT) documented severe primary unilateral narrowing of the IAC and an associated ipsilateral sensorineural hearing loss. Typical radiographic findings are described, and the relevant developmental pathology is discussed. The ipsilateral association of stenosis and hearing loss strengthens the link between narrowing of the IAC and deafness.

Surveillance CT and the prompt use of CT-guided fine-needle aspiration in patients with head and neck cancer who have undergone surgery.

OBJECTIVE: The purpose of this study was to assess the usefulness of prompt CT-guided fine-needle aspiration in the evaluation of suspected tumor recurrence seen on surveillance images of patients who had undergone surgery for head and neck cancer. SUBJECTS AND METHODS: We reviewed 32 patients who had undergone CT-guided fine-needle aspiration after surgery for head and neck cancer. CT-guided fine-needle aspiration was performed with a 22-gauge spinal needle and a cytopathologist was present to assess the adequacy of the biopsy sample. As many as five needle passes were made. RESULTS: Of the 32 cases, pathologic findings revealed squamous cell carcinoma (n = 27), mucoepidermoid carcinoma (n = 2), neuroendocrine carcinoma (n = 1), papillary thyroid carcinoma (n = 1), and adenocarcinoma (n = 1). In 20 cases (62.5%) the results of CT-guided fine-needle aspiration were positive for tumor recurrence, whereas in 11 cases (34.4%) the results were negative. In one case (3.1%) the results were nondiagnostic. Of the 11 patients with negative findings on CT-guided fine-needle aspiration, two patients had a subsequent recurrence that was not at the biopsy site. There were no complications from the procedure. CONCLUSION: When a radiologist who is trained in head and neck imaging identifies with CT a possible early recurrence of tumor, the prompt use of CT-guided fine-needle aspiration is an effective way to diagnose these tumors so that appropriate treatment can be initiated.

Imaging central skull base neural tumor spread from paranasal sinus malignancies: a critical factor in treatment planning.

Eight cases of paranasal sinus tumors with central skull base disease are presented. Each patient had coned down noncontrast and contrast-enhanced magnetic resonance imaging (MRI) studies to evaluate the tumor margins and any potential tumor spread into the cavernous sinuses, V2 and the Vidian nerve. Two patients had tumors that extended up to the face of the sphenoid bone and one had a tumor in the ventral cavernous sinus. These three patients had a complete tumor resection with postoperative irradiation. Two more patients had extensive tumor invasion of the central skull base, one was treated with only irradiation, one refused treatment. Three more patients had tumors that involved the ventral portion of the sphenoid bone with limited neural tumor extension. Two of these patients had surgery with cavernous sinus dissections followed by irradiation. One patient delayed treatment for 2 months and when he returned he had a more extensive tumor and was considered incurable by surgery. He refused further treatment. The technique of the focused MR examination and its impact on treatment planning is discussed.

Salivary glands.

This article discusses the anatomy, physiology, and pathology of the parotid, submandibular, and sublingual glands, which often are referred to as the major salivary glands. Overall, diseases of the salivary glands are relatively uncommon; however, as an organ system, they have the greatest diversity of pathology. Acute viral and bacterial inflammatory diseases are the most common salivary gland abnormalities; tumors are uncommon. The imaging approach to these lesions is discussed.

CT of pilomatrixoma in the cheek.

Pilomatrixoma is an uncommon benign tumor arising from hair follicles. They occur most commonly in the head and neck region, and are usually found in girls during the first two decades of life. These tumors may contain calcification, which, when present, is helpful in suggesting the diagnosis. We present a classic case of pilomatrixoma in the cheek of a young woman. The tumor was documented on CT studies, which showed a subcutaneous, noninvasive mass with calcifications.

Isolated vagal nerve palsy associated with a dissection of the extracranial internal carotid artery.

A 40-year-old man had paralysis of the right vocal cord. Imaging showed a dissection of the extracranial internal carotid artery, and physical examination disclosed paresis of the right side of the soft palate. To our knowledge, this is only the second report of carotid dissection presenting as an isolated vagal neuropathy. Most often, multiple lower cranial nerves are involved. The CT, MR imaging, and MR angiographic findings are presented and the topic is reviewed.

Extranodal non-Hodgkin lymphoma involving the muscles of mastication.

Involvement of the skeletal muscle by non-Hodgkin lymphoma (NHL) is unusual. The most commonly affected muscles are those of the extremities, pelvis, and gluteal regions; rarely are the muscles in the head and neck involved. We report the clinical, CT, and MR imaging findings in two patients with extranodal NHL in the head and neck region involving the muscles of mastication. One patient was immunocompetent and had lymphoma that arose within the muscles; the other was a patient with AIDS who had disseminated disease at diagnosis. In both patients, the involved muscles were isodense with normal muscles on CT scans. On MR images, the infiltrated muscles were isointense with normal muscles on the T1-weighted sequence and hyperintense on the fast spin-echo T2-weighted sequence, with variable enhancement after administration of intravenous contrast material.

A re-evaluation of imaging criteria to assess aggressive masticator space tumors.

PURPOSE: To evaluate the correlation between the gross imaging evidence of an aggressive masticator space (MS) tumor and the presence of such a MS malignancy. MATERIALS AND METHODS: Thirty patients were identified retrospectively who had a malignancy that either arose in or metastasized to the MS, had pathologic verification of the diagnosis, and had magnetic resonance (MR) and/or computed tomographic (CT) images. Specifically evaluated was the presence or absence of gross imaging evidence of mandibular erosion and the integrity of the medial MS fascia as evaluated by a smooth margin between this fascia and the parapharyngeal space fat. RESULTS: Of the 30 tumors, 28 were high-grade malignancies and 2 were histiocytoses. Of these, 5 had mandibular erosion and violation of the MS fascia, 19 had bone erosion with an intact fascia, 4 had neither bone erosion nor fascial violation (3 of these patients were under the age of 20 years), and 2 had fascial violation with no bone erosion. CONCLUSIONS: In 76.7% of patients with a malignancy arising in the MS, on imaging the medial MS fascia was grossly intact. There were 4 patients with MS malignancy and neither violation of the medial MS fascia nor mandibular bone erosion. Thus, these imaging findings may not be good criteria to evaluate the presence of a high-grade MS malignancy, especially if the patient is under the age of 20 years, in which age group MS sarcomas are more likely to arise.

Sialoblastoma (embryoma): MR findings of a rare pediatric salivary gland tumor.

We report the findings in a 21-month-old girl who had a noninfiltrating mass in the left cheek, just anterior to the masseter muscle, which, at surgery, proved to be a sialoblastoma. Sialoblastoma has a histologic appearance reminiscent of a primitive state of salivary gland development; that is, it shows an arrested state of salivary maturation. MR imaging in this case showed that the lesion was isointense with muscle on T1-weighted images, had a high-intermediate signal intensity similar to that of fat on T2-weighted images, and enhanced sparsely and nonhomogeneously.

Adenosquamous carcinoma of the facial bones, skull base, and calvaria: CT and MR manifestations.

A 62-year-old woman had proptosis of the right eye, decreased visual acuity of the left eye, and no other focal neurologic deficits. She had a grand mal seizure 1 month before admission. The CT and MR studies showed extensive bone destruction of the margins of the right orbit, the floor of the middle cranial fossa, the right cavernous sinus, and much of the calvaria. There was considerable dural disease and tumor in the right orbit, paranasal sinuses, and scalp, as well as mucoceles of the left ethmoidal sinus with desiccated secretions. The diagnosis was adenosquamous carcinoma, an aggressive tumor related to both squamous cell carcinoma and adenocarcinoma.

A Painless Retroauricular Mass in A Patient with Myotonic Dystrophy: Computed Tomographic Documentation of the Bone Changes that Occur in the Skull Base.

A 16-year-old male with a history of neonatal myotonic dystrophy had a painless enlarging left retroauricular mass. Computed tomography showed an enlarged frontal sinus, thickened apparently normal bone in the anterior left clinoid process, doresum sellae, and all portions of the temporal bones. In particular, there was bone production in the left retroauricular region and along the margins of the left internal auditory canal. The left temporomandibular joint was also dislocated. This is the first case report to document the dynamic aspect of the bone changes in this dystrophy.

The role of imaging in the diagnosis of giant cell tumor of the skull base.

An expansile temporal bone lesion above the temporomandibular joint (TMJ) in a 55-year-old woman was initially diagnosed as pigmented villonodular tenosynovitis. Preoperative embolization of the tumor had resulted in excessive tumoral hemorrhagic pigment. The surgical and CT findings suggested that the TMJ was not involved, and a final diagnosis of giant cell tumor was made.

Epithelial-myoepithelial carcinoma of the parotid gland.

We describe an unusual salivary neoplasm, an epithelial-myoepithelial carcinoma (EMEC) of the parotid gland, that occurred in a 64-year-old man. A CT scan showed a fairly well defined heterogeneous lesion with smooth margins and slight enhancement. MR images showed a lesion with intermediate T1-weighted signal intensity and a relatively high T2-weighted signal intensity. Although the imaging characteristics of EMEC on both CT and MR studies are nonspecific, clinicians and radiologists must be aware of its high local recurrence rate, which has been reported to approach 50% in some series, and thus the need for periodic postoperative imaging to detect early recurrence.

Pantopaque simulating thrombosed intracranial aneurysms on MRI.

A patient is presented in whom iophendylate (Pantopaque) within the basal cisterns closely resembled the appearance on MRI of thrombosed aneurysms of the middle cerebral arteries. The sometimes subtle differences between the appearances on MRI of Pantopaque and aneurysmal clot are discussed to permit accurate diagnosis without resorting to more invasive diagnostic tests, such as cerebral angiography.

Egg shell nodal calcification in a patient with sinus histiocytosis with massive lymphadenopathy treated with interferon.

CT showed egg shell calcification in the cervical lymph nodes in a patient with sinus histiocytosis with massive lymphadenopathy treated for 1 year with interferon. CT scans before interferon treatment had shown no nodal calcification.

Giant varices in portal hypertension: CT findings.

Two cases of giant varices in portal hypertension are presented. Dynamic computed tomography (CT) was useful in establishing that the masses were in fact dilated veins.