Submandibular gland mucocele: diagnosis and management.

Mucoceles originating from the submandibular gland are extremely rare. A review of the English literature resulted in identification of only 5 such cases. We have diagnosed and treated 2 submandibular mucoceles. Both lesions were removed in continuity with the submandibular and sublingual glands. No complications and no recurrences have occurred to date. The diagnosis of these lesions is complicated because of the lack of specific clinical diagnostic criteria and the similarity between submandibular mucoceles and plunging or cervical ranulas. Computerized tomography and specifically the presence of a so-called "tail" sign is pathognomonic for plunging ranula. This sign is absent in mucoceles originating in the submandibular glands. The treatment strategies vary as well. A diagnostic algorithm and a surgical rationale for treatment of submandibular mucoceles are presented.

Bone scan in tumor-induced osteomalacia.

A 66-yr-old female was admitted with a 3-yr history of generalized bone pain and nasal obstruction. CT and MRI of the head revealed a large nasal mass. A whole-body bone scan revealed multifocal lesions of increased activity. Surgical removal of the nasal tumor revealed hemangiopericytoma. The patient improved clinically and a repeat bone scan 10 mo after surgery revealed markedly improved findings.

Nasopharyngeal melanotic melanoma: MR characteristics.

This report presents a rare case of nasopharyngeal melanoma with maxillary sinus extension and lymph node metastasis. The unusual magnetic resonance signal features and the differential diagnosis are discussed.

Eosinophilic granuloma of the cavernous sinus and orbital apex in an HIV-positive patient.

A 35-year-old HIV-positive woman with painful ophthalmoplegia, sensory loss extending to all branches of the trigeminal nerve, and progressive optic neuropathy was found to have eosinophilic granuloma of the cavernous sinus, superior orbital fissure, and orbital apex. There was no radiologic evidence of a lytic bone lesion within the skull or orbit and clinical evidence suggested a primary intracranial origin for this lesion. This is the first case of a cavernous sinus syndrome caused by eosinophilic granuloma and the first time HIV infection is reported in association with histiocytosis-X.

The bull's-eye sign of extracranial cervical aneurysms.

Extracranial, cervical aneurysms and arterial thrombosis are uncommon entities. In most cases, they have diagnostic clinical presentations. However, on occasion the history and physical findings do not clearly suggest their presence. In these cases, postcontrast computed tomography scans can aid in rapidly establishing the correct diagnosis by revealing a "bull's-eye" appearance within the mass (vessel lumen). The diagnosis is less difficult to make when the involved vessel is the carotid artery, because this artery is routinely identified on postcontrast computed tomography scans and the lesion can be easily placed along its course. The vascular origin of such a lesion is not usually evident on computed tomography if the process does not lie along the course of a major vessel. In these cases, the bull's-eye sign can establish the diagnosis so that prompt consideration can be given to angiography and therapy.

Intraosseous petrous apex neuroma: CT findings.

An avascular, contrast enhancing intraosseous petrous apex mass was discovered on CT in a patient with prior colonic carcinoma and acute myelocytic leukemia. A normal bone scan made metastasis unlikely and surgery revealed a neuroma. The differential diagnosis is discussed.

Differentiation of large suprasellar masses by evaluation of the superior margin.

Differentiation of suprasellar masses by computed tomography criteria depends on intrasellar extension, patterns of calcification and enhancement, associated bony reaction, and cystic changes. In the case of a homogeneously enhancing suprasellar mass that does not exhibit any of these differentiating findings, separating a suprasellar meningioma from a large suprasellar pituitary adenoma has been quite difficult. We reviewed the computed tomography findings of 42 such tumors. There were 19 meningiomas and 23 pituitary adenomas chosen that had few or none of the commonly applied findings used in differentiation. Evaluation of the superior contour of these masses seems a reliable sign to use in this situation. A single upward convex curve correlated with a meningioma in 15 of 19 cases (78%), whereas a multiple upward convex curve correlated with a pituitary adenoma in 19 of 23 cases (82%). Although some pitfalls were encountered when employing this sign--such as pseudolobulations caused by the adjoining cavernous sinus, dural, or vascular structures--it nonetheless led to the correct diagnosis in approximately 80% of cases.

The postcraniectomy site: CT appearance.

The hospital records and computed tomographic (CT) scans of 124 postcraniectomy patients were reviewed. The normal CT appearance of the operative site was defined and referred to as the "meningogaleal complex" (MGC). The CT characteristics of postoperative infections, intraaxial tumor recurrences, extraaxial tumor recurrences, and the various forms of postoperative cerebrospinal fluid collections were identified and differentiated by comparison with the normal scans. Specifically, when compared with the "postoperative baseline" anatomy, smooth thickening of the MGC often indicated postoperative infection (six cases), while nodular thickening heralded recurrent extraaxial tumor (eight cases). Recurrent intraaxial tumor adjacent to the craniectomy site caused no change in the MGC itself. A knowledge of the normal postoperative appearance of the MGC as well as good communication with the neurosurgeon can allow earlier detection of postoperative complications.

Cystic adult medulloblastomas.

The computed tomography scans of four patients who had a medulloblastoma are reviewed. In all the cases, atypical findings were present--specifically, cystic or lucent areas within the tumor. The importance of this uncommon finding associated with adult medulloblastoma is discussed.

Malignant teratoma of the parapharyngeal space in an adult: a rare lesion presenting as cervical cord compression.

The 12th case of a cervical teratoma in an adult is presented. This malignant lesion, located in the parapharyngeal space, presented clinically with signs and symptoms of a cervical cord compression secondary to metastases. The computed tomography, dynamic scan, and angiography workup of this patient is presented, and the literature is reviewed.

Computed tomography of solitary spinal osteochondromas.

Solitary osteochondromas rarely occur in the axial skeleton. These benign tumors may cause a variety of symptoms while remaining difficult to recognize by plain radiographic and myelographic studies. We present three cases of solitary osteochondromas of the spine and demonstrate the CT findings of these unusual tumors.

Parenchymal cysts of the lower neck.

We report on the appearance of parathyroid, thyroid, and cervical thymic cysts on computed tomography (CT) scans. The differential diagnostic considerations include thyroglossal and branchial cleft cysts, cystic hygromas, primary and metastatic tumors, dermoids, teratomas, choristomas, tracheoesophageal and cervical bronchogenic cysts, as well as cystic neuromas, abscesses, and lipomas. Most cannot be differentiated using CT alone and require clinical observations, laboratory testing, and surgical and histologic findings for definitive diagnosis. Our experience with these rare lesions is reported, and the differential diagnoses are discussed.

Coexistence of a nasal mucoepidermoid carcinoma and sphenoid mucoceles: CT diagnosis and treatment implications.

Mucoepidermoid carcinomas of minor salivary gland origin rarely arise in the nasal cavity. A patient with such a tumor in association with bilateral sphenoid sinus mucoceles is presented. This diagnosis was established preoperatively by CT and allowed an attempt at curative surgery to be made. The CT and pathological findings are discussed.

CT myelography of spontaneous spinal epidural hematoma.

A case of so-called spontaneous epidural hematoma is presented. A new constellation of myelographic and CT myelographic signs are described that may assist in localizing a mass within the spinal epidural space.