MR Findings of Recurred Giant Cell Tumor

PURPOSE: To describe MR findings of recurred giant cell tumor of bone. MATERIALS AND METHODS: MR imagings of ten cases of pathologically proven recurrence of giant cell tumor were retrospectively analyzed. Location of recurrence, multiplicity of recurred tumor, signal intensity and homogeneity, pattern of gadolinium enhancement, soft tissue and articular surface involvement were evaluated. RESULTS: Tumors were located in peripheral portion of previous operation site(80%). Six cases recurred as multiple lesions. Tumor showed low signal intensity on T1 weighted images(100%), high signal intensity on T2 weighted images(100%) and inhomogeneous peripheral rim enhancing pattern(75%). Soft tissue and articular surface involvement were also demonstrated. CONCLUSION: We concluded that characteristic MR findings of recurred giant cell tumor could be helpful in early detection and precise evaluation of tumor recurrence.

Granulomatous Colitis: Findings on Double Contrast Barium Enema and Follow-up Studies

PURPOSE: To evaluate the radiologic findings of granulomatous colitis on double contrast barium enema and changes on follow-up studies. MATERIALS AND METHODS: Serial double contrast barium enemas of six patients with granulomatous colitis confirmed by endoscopic biopsy were reviewed. We analyzed the radiologic findings and their follow-up changes, including aphthous ulcers, lymphoid hyperplasia, deep ulcers, cobble stone appearance, geographic ulcers, asymmetric involvement of ulcers, skip lesions, sinus tract, fistula formation, pseudosacculation, focal stricture, and small bowel involvement. RESULTS: Pretreatment double contrast baruim enema findings were aphthous ulcers in five patients, deep ulcer in six, cobble stone appearance in five, longitudinal geographic ulcers in two, fistulas in one, pseudo-sacculations in two, focal stricture in one, and pseudopolyps in six. Also, anal ulcers were observed in two patients, asymmetric involvement of ulcers in three, skip lesions in four, and small bowel involvement in five in five patients proved to have inactive disease after treatment, aphthous ulcers and deep ulcers disappeared. Geographic ulcers of two patients and anal ulcer of one patients decreased in size or depth. Pseudosacculation in one patient disappeared. Pseudopolyps decreased in two patients, increased in one, and decreased after increase in two. One patient whose disease remained active after treatment showed maintenance or increase of ulcers or fistula. And their pseudosacculation or focal stricture unchanged and pseudopolyps decreased. CONCLUSION: The major radiologic findings of chronic granulomatous colitis on double contrst barium enema are aphthous ulcer, deep ulcer, cobble stone appearance, discontinuity of the lesion, and coexistence of ulcers and pseudopolyps. And, double contrast barium enema is good follow-up modality because its findings correlate with clinical course of the granulomatous colitis after treatment.

Granulomatous Colitis: Findings on Double Contrast Barium Enema and Follow-up Studies

PURPOSE: To evaluate the radiologic findings of granulomatous colitis on double contrast barium enema and changes on follow-up studies. MATERIALS AND METHODS: Serial double contrast barium enemas of six patients with granulomatous colitis confirmed by endoscopic biopsy were reviewed. We analyzed the radiologic findings and their follow-up changes, including aphthous ulcers, lymphoid hyperplasia, deep ulcers, cobble stone appearance, geographic ulcers, asymmetric involvement of ulcers, skip lesions, sinus tract, fistula formation, pseudosacculation, focal stricture, and small bowel involvement. RESULTS: Pretreatment double contrast baruim enema findings were aphthous ulcers in five patients, deep ulcer in six, cobble stone appearance in five, longitudinal geographic ulcers in two, fistulas in one, pseudo-sacculations in two, focal stricture in one, and pseudopolyps in six. Also, anal ulcers were observed in two patients, asymmetric involvement of ulcers in three, skip lesions in four, and small bowel involvement in five in five patients proved to have inactive disease after treatment, aphthous ulcers and deep ulcers disappeared. Geographic ulcers of two patients and anal ulcer of one patients decreased in size or depth. Pseudosacculation in one patient disappeared. Pseudopolyps decreased in two patients, increased in one, and decreased after increase in two. One patient whose disease remained active after treatment showed maintenance or increase of ulcers or fistula. And their pseudosacculation or focal stricture unchanged and pseudopolyps decreased. CONCLUSION: The major radiologic findings of chronic granulomatous colitis on double contrst barium enema are aphthous ulcer, deep ulcer, cobble stone appearance, discontinuity of the lesion, and coexistence of ulcers and pseudopolyps. And, double contrast barium enema is good follow-up modality because its findings correlate with clinical course of the granulomatous colitis after treatment.

Delayed Effect of Contrast Enhancement in Brain Tumors on MRI

PURPOSE: To evaluate the degree of contrast enhancement of intracranial tumors on delayed (6-8min.) MR imaging after administration of Gd-DTPA. MATERIALS AND METHODS: Both immediate and delayed post-contrast MR imagings were studied prospectively in 35 patients. with brain tumors (11 gliomas, 6 meningiomas, 4 neurinomas, 5 parencymal metastases, 5 hemangioblastoma, 4 others) at either 0.5 T or 2.0 T unit. After precontrast TI-, proton-density, and T2-weighted spin echo images were obtained, each patient underwent Tl-weighted imaging immediately following infusion of 0.1 mmol/Kg of Gd-DTPA. Subsequently, the second postcontrast Tl-weighted images were obtained with no additional injection of the contrast media. Time-interval between the postcontrast immediate and the delayed images was approximately 6-8 minutes. Degree of contrast enhancement of the lesions was assessed both visually and quantitatively. For quantitative study, contrast enhancement ratio(CER) of tumors was calculated in both immediate and delayed post-contrast images. RESULTS: There was stronger visual enhancement in 7 of 11 cases with gliomas and 3 of 5 cases with parenchymal metastasis on delayed images when compared with immediate images, whereas all 10 cases of extraaxial tumors(meningiomas and neurinomas) showed decreased enhancement on delayed images. Quantitatively, mean CERs of gliomas and metastases were higher on delayed study than on immediate study by 20. 5% and 49.2%, respectively. Extraaxial tumors showed decrease of CER on delayed study by 19.7% as compared with that of immediate study. Hemangioblastomas showed visually poor enhancement on delayed image in 4 cases and equal enhancement on both immediate and delayed images in remaining one case, and quantitatively demonstrated decrease of CER on delayed study by 15.4%. CONCLUSION: Since there was more conspicuous contrast enhancement in many intraaxial tumors such as gliomas and metastases on 6-8 minutes delayed post-contrast MR study, the delayed post-contrast study may be needed in some intraaxial tumors for their characterization, and may also be helpful for the differential diagnosis between intraaxial and extraaxial tumors.

Sedation of Children for MR or CT Imaging Examination Using Chloral Hydrate

PURPOSE: Pediatric sedation is an important factor for obtaining the images of good quality. We performed this study to analyze the efficacy of our sedation protocol using chloral hydrate. MATERIALS AND METHODS: We collected prospectively 151 sedation records of children(1 day-15 years old), who were sedated with chloral hydrate for MR(n=112) or CT(n=39) studies. We initially administered 50mg/Kg orally(n=94) or rectally(n=57) 30 minutes before the scheduled examinations, and then administered additionali dose (second dose :25-35mg/Kg, third dose:10-15mg/Kg) to patients whom initial dose failed to sedate. RESULTS: Satisfactory sedation was achieved by initial administration in 109 patients(72%) without si difference between oral(per oral: P.O.) and rectal(per rectal: P.R.) administration. Second dose was required in 28% and third dose in 5%. MR and CT examinations required second dose in 36(32%) and 6 patients(15%), respectively. P.O. -patients vomited in 5%. P.R. -patients defecated in 22% after initial administration. There were no other serious complications. Time interval from the drug administration to the start of examinations was 33 minutes in initial-dose-group and 64 minutes in additional-dose-group. Two patients could not complete MR examination due to early arousal. Prolonged sedation, requiring more than 30 minutes for alertness after MR and CT examinations, was encountered in twenty(18%) and two patients(5%), respectively. CONCLUSION: Our protocol using chloral hydrate(P.O. or P.R.) is thought to be an effective and safe method for pediatric sedation for MR or CT imaging.

Joubert Syndrome: Clinical Manifestations and Magnetic Resonance Imaging

PURPOSE: Joubert syndrome presents neonatal respiratory abnormalities and other clinical manifestations. Pathologically the patients show hypoplasia or agenesis of cerebellar vermis and other intracranial anomalies. Our purpose is to evaluate the clinical manifestations and MR findings of Joubert syndrome. MATERIALS AND METHODS: Among the patients presenting with clinical stigmata of Joubert syndrome and agenesis of vermis on MR imaging, eight patients who did not satisfied the criteria of Dandy-Walker malformation, tectocerebellar dysraphia and rhombencephalosynapsis were selected. MR findings and clinical manifestation were analyzed. RESULTS: On MR imaging, agenesis of the cerebellar vermis (all cases), hypoplasia of the cerebellar peduncle (6cases), fourth ventricular contour deformity(6cases), tentorial elevation (4cases), deformity of the lateral ventricles (4cases), dysgenesis of the straight sinus (3cases) were demonstrated. Other findings were abnormalities of corpus callosum (3cases), falx anomalies (3 cases), occipital encephalomeningocele (2 cases) and fluid collection in posterior cranial fossa (2cases). Clinical manifestations were developmental delay (5cases), abnormal eyeball movement (3cases), hypotonia (2 cases), neonatal rerspiratoy abnormality (2cases), etc. CONCLUSION: Joubert syndrome showed various clinical manifestations and intracranial anomalies. MR imaging is an useful modality in detection of the cerebellar vermian agenesis and other anomalies of the patients.

Hallervorden-Spatz Disease: 2 Cases of Siblings

We report two patients with Hallervorden-Spatz disease, who were diagnosed by same MR findings of marked low signal intensity in the globus and substantia nigra. They presented with ataxic and spastic gait, intention tremor, delayed mental development, and dysarthria. They were 7 year-old male and 8 yea r-old female siblings, who were healthy until 3 years of age when they suffered from progressive symptoms. T2-weighted images showed marked low signal intensity in the globus pallidus and substantia nigra indicating an increased irondeposition, and it might suggest Hallervorden-Spatz disease.