Recurrent Osteosarcoma in Skull Base: A Case Report

Osteosarcomas are highly malignant bone tumors which commonly affect metaphyseal portions of long bones and those of the skull are distinctly rare as primary neoplasm. We report a case of recurrent osteosarcoma originated from the skull base which destructed sphenoid bone in two months. The CT and MR images of 28 years old man with headache, dizziness, and loss of touch sense in right buccal area showed 3-cm sized homogenously well-enhancing mass with internal small cystic portions. Craniotomy and mass excision was done and chemotherapy was combined for 1 month. After about 2 month, follow up MR images showed larger recurrent mass in original site and confirmed as the same osteosarcoma after 2nd operation.

Recurrent Osteosarcoma in Skull Base: A Case Report

Osteosarcomas are highly malignant bone tumors which commonly affect metaphyseal portions of long bones and those of the skull are distinctly rare as primary neoplasm. We report a case of recurrent osteosarcoma originated from the skull base which destructed sphenoid bone in two months. The CT and MR images of 28 years old man with headache, dizziness, and loss of touch sense in right buccal area showed 3-cm sized homogenously well-enhancing mass with internal small cystic portions. Craniotomy and mass excision was done and chemotherapy was combined for 1 month. After about 2 month, follow up MR images showed larger recurrent mass in original site and confirmed as the same osteosarcoma after 2nd operation.

CT and MR Findings of the Telangiectatic Osteosarcoma Arising from the Skull: Case Report

Telangiectatic osteosarcoma is rare malignant tumor causing aggressive bone destruction, though the skull is very rarely involved. We report a case in which the condition affected the skull of a 17-year-old male, involving the parietal bone and with intracranial and extracranial extension. CT and MR images depict an osteolytic lesion of the right parietal bone and an enhancing solid mass in the intracranial and extracranial portions. Matrix calcifications, periosteral reaction, and multiple fluid-fluid levels are seen within the masses.

Imagings of Skull Vault Lesions

Lesions of the skull vault are often incidentally encountered during in plain radiography, CT, and MR imaging of the brain and benign lesions are more common than primary malignancies. The usefulness of plain skull films is limited, but when combined with CT or MRI, there is a high probability of accurate diagnosis. The aim of this essay is to describe a wide range of cranial lesions and to illustrate their distinguishing features.

MR Findings of Calvarial Eosinophilic Granuloma

PURPOSE: The purpose of this study was to evaluate the MR findings of calvarial eosinophilic granuloma. MATERIALS AND METHODS: We reviewed the MR imaging studies of nine patients [M:F=3:6, aged 6 -35 (mean, 20.5) years] with pathologically proven eosinophilic granuloma in the calvaria. The findings were evaluated for involvement of the diploic space, changes in adjacent bone marrow, distinction of the transitional zone, pattern of bone destruction, signal intensity and contrast enhancement of the tumor, and contrast enhancement of the adjacent dura. RESULTS: All lesions involved the diploic space, showed no change in adjacent bone marrow, and had a distinct transitional zone. In most (8/9) cases there was asymmetric bony destruction. On T1-weighted images, signal intensities of the tumors varied, while on T2-weighted images, hyperintensity was observed in seven cases, isointensity in one, and hypointensity in one. After the administration of contrast material, enhancement was homogeneous in four cases and inhomogeneous in five. Enhancement of the adjacent dura was demonstrated in all nine cases. CONCLUSION: The characteristic MR findings of calvarial eosinophilic granuloma are variable signal intensity on T1WI, high signal intensity on T2WI, and marked contrast enhancement; in addition, there is a distinct transitional zone, asymmetrical bony destruction, and associated dural enhancement.

Atypical CT and MR Features of Chondroid Chordoma at the Base of the Skull: A Case Report

We report a case of chondroid chordoma without calcification in which T2-weighted MR images revealed homogeneous high signal intensity. The tumor was located in the left middle cranial fossa extending to the cerebellopontine angle and with displacement of the pituitary gland to the right side. Precontrast CT scans showed a homogeneous low -density mass, without calcification. T1-weighted MR images of the mass demonstrated relatively homogeneous low signal intensity, T2-weighted images showed homogeneous high signal intensity, and post -contrast T1-weighted images revealed somewhat heterogeneous enhancement.

Intracranial Inflammatory Pseudotumors: MRI and CT Findings

PURPOSE: The purpose of this study was to describe the MR imaging and CT findings of intracranial inflammatory pseudotumors. MATERIALS AND METHODS: We reviewed the MR imaging (n=8) and CT (n=4) studies of eight patients (M:F = 4:4, mean age: 41 years) with pathologically proven intracranial inflammatory pseudotumor. The findings were then evaluated with regard to location, shape, MR signal intensity, CT density and degree of contrast enhancement of the lesion, surrounding parenchymal edema, adjacent bone change and the location of accompanying extracranial lesion. RESULTS: In two patients, the parietal convexity was involved unilaterally, with no extracranial mass, and in the other six, the middle cranial fossa was involved unilaterally and extracranial mass was present. The lesion also involved the tentorium in four cases, the cavernous sinus in four, the anterior cranial fossa in one, and the posterior cranial fossa in one. The location of extracranial mass was the mastoid and middle ear cavity in two cases, the infratemporal fossa in two, both the infratemporal fossa and paranasal sinuses in one, and the orbit in one. MR images showed diffuse dural thickening in all eight cases, leptomeningeal thickening in four, and focal meningeal-based mass in two. As seen on T1-weighted images, the lesions were isointense to gray matter in eight cases, and on T2-weighted images were hypointense in seven cases and isointense in one. Marked homogeneous contrast enhancement was seen in all eight cases. The lesions seen on brain CT, performed in two cases, were isodense. Adjacent brain parenchymal edema and the destruction of adjacent bones were each seen in five cases. CONCLUSION: The characteristic MR findings of intracranial inflammatory pseudotumors are(1) diffuse dural thickening;(2) a focal meningeal-based mass which on T2-weighted images is seen as hypointense; and marked (3) contrast enhancement : these findings are, however, nonspecific. In order to differentiate these tumors, an awareness of these findings is, however, useful.

Metastatic Thy roid Carcinoma of Jugular Foramen Simulating Glomus Jugulare Tumor: A Case Report

We report a case of hyper vascular metastatic thyroid carcinoma of the jugular fora-men simulating a glomus jugulare tumor. Computed tomography(CT) revealed areas of irregular lytic bony destruction of the left jugular foramen, as well as characteristic in vasion routes of a glomus jugulare tumor. Magnetic resonance(MR) imaging and angiography demonstrated a hypervascular mass similar to a glomus tumor.

Cranial Fasciitis in a Child: A Case Report

Cranial fasciitis is a rare fibroblastic tumor which shows a predilection for the scalp and skull of youngchil-dren. Histologically, cranial fasciitis is identical to nodular fasciitis which is typically found in theextremities of adults, though is unique in that it may present as an osteolytic lesion of the skull. We report acase of cranial fasciitis in a 20-month-old girl, describing the ultrasonography, CT and MRI findings.

Chordoma versus Chondrosarcoma of the Central Skull Base: MR and CT Findings

PURPOSE: It is known that due to both their imaging and pathologic features, the accurate differentiation ofchondrosarcoma from chordoma is difficult. Through an analysis of MR and CT findings, this study aims to determinethe differential points between these two tumors. MATERIALS AND METHODS: In 21 patients, CT and MR imagingstudies of chordoma(n=12) and chondrosarcoma(n=9) at the base of the skull were retrospectively reviewed.Diagnosis had been established by histologic examination of surgically removed specimens. Eleven of the chordomaswere subclassified as 'conventional' and one as 'chondroid'; eight chondrosarcoma were 'conventional' andone was 'myxoid'. Four chordoma patients underwent CT and MR ; in six, only MR was performed ; and in two, onlyCT. Eight chondrosarcoma patients underwent both CT and MR, while in one, only CT was performed. All scans wereretrospectively evaluated for the location(midline/off-midline), direction of extension, margin and shape, bonydestruction and calcification, MR signal intensity and enhancement patterns of the tumors. Degree of calcificationwas graded from I to III. RESULTS: The epicenter of the mass of ten chordomas (83%) was midline, in twochondrosarcomas(22%), this was off-midline. Foci of calcification were observed in three of eleven chordomas(27%),and heavy calcification (grade III) was observed in one. In contrast to these findings, foci of calcificationswere observed in eight of nine chondrosarcomas (89%) and grade III calcification was observed in five. In bothtumors, calcification was coarse. Between the two kinds of tumor, there were no significant difference in MRsignal intensity and enhancement patterns, margin and shape, or direction of extension. CONCLUSIONS: Although MRand CT findings were similar in both types of tumor, location and degree of calcification may be features whichusefully distinguish chordoma from chondrosarcoma.