Severe diffuse systemic amyloidosis with involvement of the pharynx, larynx, and trachea: CT and MR findings.

Amyloidosis is a term applied to a diverse group of disorders that share the deposition of amyloid protein in various extracellular tissues. Systemic amyloidosis may involve almost any organ system in the body including regions in the head and neck; however, pharyngeal involvement is rare, with only 12 cases having been previously reported. Ten of these cases were localized disease, and only 2 cases were systemic amyloidosis. We present the case of a patient with severe diffuse systemic amyloidosis with extensive involvement of the pharynx, larynx, trachea, lungs, eyelids, and breasts. We also review the imaging characteristics and pertinent literature.

Unique imaging findings in the facial bones of renal osteodystrophy.

Facial skeletal changes associated with hyperparathyroidism assume 3 radiographic patterns: osteitis fibrosa cystica, fibrous dysplasia, and leontiasis ossea. The 3rd pattern is unique to renal osteodystrophy. We report a case of uremic leontiasis ossea with CT images illustrating significant hypertrophy of the jaws with serpiginous tunneling within the bone and poor visualization of the cortical bone.

Palatal enlargement in chronic lymphocytic leukemia.

Palatal involvement in chronic lymphocytic leukemia (CLL) is rare and has only been reported 3 previous times in the non-radiology literature. To our knowledge this is the first imaging description of this entity. Based on our experience, when smoothly lobulated, homogeneous masses are identified on the oral surface of the hard palate, the diagnosis of CLL should be considered.

Bisphosphonate-associated mandibular osteonecrosis.

A 66-year-old man with multiple myeloma treated with zoledronic acid, melphalan, and prednisone after a tooth extraction developed severe osteonecrosis of the mandible that was nonresponsive to antibiotic therapy. A CT scan showed innumerable fragmented sequestra in the mandible and some adjacent soft tissue fullness around the mandible. The association between the use of bisphosphonates and osteonecrosis of the jaw has been described only recently.

Schwannomas of the larynx: review and computed tomographic scan analysis.

Neurogenic tumors consist of schwannomas, neurofibromas, and neurosarcomas that arise from the Schwann cell of a peripheral nerve. Their occurrence in the larynx is rare, with only 115 cases having been reported. Three new cases are presented, the literature is reviewed, and the first computed tomographic (CT) scan of a benign schwannoma of the larynx is demonstrated. The diagnosis and treatment of these tumors and the CT scan analysis are discussed.

Peripheral nerve sheath tumors of the paranasal sinuses.

Only 4% of peripheral nerve sheath tumors of the head and neck occur in the paranasal sinuses. The most commonly involved sinus is the maxillary antrum and the most common histologic type is benign schwannoma. Two new cases of schwannoma occurring in the sphenoid and maxillary sinuses are reported. The clinical pathologic, and radiographic features of these lesions are reviewed.

Inflammatory disease involving a concha bullosa (enlarged pneumatized middle nasal turbinate): MR and CT appearance.

An enlarged pneumatized middle turbinate, called a concha bullosa, may be the site of inflammatory disease ranging from simple mucosal thickening to a mucocele. Four patients with inflammatory disease involving a concha bullosa were studied with MR and/or CT. Both imaging techniques detected the presence of mucosal inflammation and a mucocele within the concha bullosa, but CT better demonstrated the thin bony wall of the mucocele, allowing differentiation from other soft-tissue nasal masses.

The significance of sinonasal radiodensities: ossification, calcification, or residual bone?

PURPOSE: To determine whether very radiodense material within a sinonasal soft-tissue mass on CT can be differentiated as calcification, ossification, or residual bone. METHODS: We retrospectively described the radiodensities within 235 sinonasal soft-tissue masses as discrete, solitary or multiple, or as a diffuse process with either a well-defined or poorly defined margin. They were also classified as calcification, ossification, or residual bone. Findings were correlated with pathologic specimens. RESULTS: Residual bone was underdiagnosed; calcification was overdiagnosed. A solitary discrete density was most likely to be calcification within an inflammatory mass. However, multiple discrete densities were as likely to be in a tumor as in an inflammatory lesion. If the process was diffuse with a well-defined margin, it was most likely to be a benign fibroosseous lesion. If the process was diffuse with a poorly defined margin, it was most likely to be a high-grade sarcoma. Densities within inverted papillomas were shown to be residual bone, not calcifications; densities within esthesioneuroblastomas were calcifications. CONCLUSION: Radiodensities may help in refining a CT diagnosis, but one may not know based on CT whether the density is a calcification, ossification, or residual bone.

Digital angiography of pulsatile masses in the neck.

Twenty-six consecutive patients with pulsatile neck masses were studied with digital subtraction angiography (DSA) by venous injection, computed tomography (CT), and conventional direct angiography. The neck masses proved to be secondary to tortuous and ectatic carotid or subclavian arteries in 13 cases, resulted from subclavian artery aneurysms in three cases, and resulted from tumor in 10 cases. DSA alone was sufficient for diagnosis in 16 of 26 cases. CT was performed in 15 cases and was contributory in 10. It was most useful when a tumor was demonstrated or suspected on DSA. Conventional angiography was performed in six cases. It contributed no useful information when arteriosclerotic vascular changes were the source of the neck mass, and added useful diagnostic information in only two of 10 neck tumors.

Fluid-fluid levels in benign neurogenic tumors.

We report two cases of cystic lesions in the head and neck, one a cystic schwannoma and the other a neurofibroma, both of which showed fluid-fluid levels on MR images. The differential diagnosis of fluid-fluid levels in the head and neck region should include cystic hygromas, aneurysmal bone cysts, soft-tissue cavernous hemangiomas, and simple bone cysts.

Bilateral orbital metastases from prostate carcinoma: case presentation and CT findings.

A patient with known prostatic cancer presented with bilateral orbital masses. On CT there was a bulky soft-tissue mass in the cranial aspect of each orbit. An open biopsy revealed undifferentiated tissue that stained strongly positive for prostatic-specific acid phosphatase, confirming the diagnosis of metastatic prostate carcinoma.

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.

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.

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.

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.

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 palatal dentigerous cyst arising from a mesiodente.

Dentigerous cysts can develop from unerupted primary, permanent, or rarely supernumerary teeth. When a supernumerary tooth is in the maxilla, near the midline, it is called a mesiodente. Such a mesiodente lies in the palate and a cyst developing about this tooth can extend directly up into the nasal fossae. More commonly a dentigerous cyst arising from unerupted maxillary teeth occurs about the molar, premolar, or canine teeth and the cyst extends up into the maxillary sinus. The CT and MR findings in a rare case of a dentigerous cyst of a mesiodente are presented.

Rare presentations of ordinary lipomas of the head and neck: a review.

The ordinary lipoma is the most common neoplasm of mesenchymal origin. Only 13% of them arise in the head and neck region and most of these occur subcutaneously in the posterior neck. Rarely, they can develop in the anterior neck, infratemporal fossa, and in or around the oral cavity, pharynx, larynx, and parotid gland. Clinically, they can be confused with other benign lesions; however, CT allows a specific diagnosis to be made in virtually all cases. This article reviews the CT appearance and differential diagnoses of lipomas in these rare locations and discusses the rare infiltrating lipoma and the relationship between parotid lipomatosis and sialosis.