Wallerian degeneration is well known as the anterograde degeneration of axon and their accompanying myelin sheath from injury to the proximal portion of the axon or its cell body. The most common cause of wallerian degeneration is cerebral infarction. Authors experienced three patients with old hemispheric infarct with typical wallerian degeneration in the brain stem, which was demonstrated by magnetic resonance imaging (MRI) in two cases and CT in one case. This report demonstrates the wallerian degeneration in the corticospinal tract on the MRI and CT with the brief review of the literatures.
Axons ; Brain Stem ; Brain* ; Cell Body ; Cerebral Infarction ; Humans ; Magnetic Resonance Imaging* ; Myelin Sheath ; Pyramidal Tracts ; Wallerian Degeneration*

PURPOSE: Lymphoma is considered when multiple, nonnecrotic lymph nodes are present in the superficial and deep lymphatic chains, especially if they are large and bilateral, on CT scan. It is reported that combined nodal and extranodal presentation of HD is uncommon. However, we found central low density in involved lymph node of NHL, and combined nodal and extranodal disease in HD, not infrequently. The purpose of this study is to ascertain whether our findings may be characteristics of NHL and HD. MATERIALS AND METHODS: CT findings with contrast enhancement were reviewed in 23 patients with untreated neck lymphoma:18 NHL and 5 HD. The followings were analyzed in each case: nodal or extranodal involvement; unilateral or bilateral involvement; presence or absence of central low density with peripheral enhancement in nodal lesion ;infiltration into adjacent structures. Nodal and extranodal lesions were confirmed by pathologic studies. RESULTS: Of 18 patients with NHL, nine cases had nodal disease and the rest had combined nodal and extranodal disease. Lymphadenopathy was bilateral in ten cases and unilateral in eight. Five cases with HD were composed of three combined nodal and extranodal diseases and two nodal diseases. Central low density of involved lymph node was shown in eight cases of 18 NHL and in one case of five HD. CONCLUSION: Central low density with peripheral enhancement was not uncommon in NHL, in contrast to HD. Hence, it is suggested that in case of nodal necrosis, NHL be also considered, besides tuberculous lymphadenitis and metastatic lymphadenopathy. It is not considered that nodal or extranodal disease, and unilateral or bilateral involvement are of high significance in differentiation of NHL from HD.
Hodgkin Disease* ; Humans ; Lymph Nodes ; Lymphatic Diseases ; Lymphoma ; Lymphoma, Non-Hodgkin* ; Neck* ; Necrosis ; Tomography, X-Ray Computed ; Tuberculosis, Lymph Node

PURPOSE: To evaluate the surface anatomy of the central sulcus(CS), precentral gyrus(PrCG) and postcentral gyrus(PoCG) on the basis of sulci pattern on MR images. MATERIALS AND METHODS: The MR images were obtained in the plane 10 degree angled to the orbitomeatal line. The MR images of 120 subjects(6 months to 79 years) with normal anatomy were analyzed and another four subjects with known space occupying lesions were also reviewed. RESULTS: The identification of gyri was feasible on the axial T1WI from anterior to posterior and from upper to lower images. The STS demonstrated symmetric pattern on both sides in 84 of 120 cases (70%), including two cases of prominent STS pattern. The asymmetric pattern was seen in 36 of 120 cases (30%):14 of 120 cases (12%) on the right and 22 of 120 cases (18%) on the left at 4.5 cm above the level of the splenium of corpus callosum. The PrCG and PoCG and CS were identified well in all cases with the use 'of the sulci pattern. CONCLUSION: The identification of the gyri on the basis of the cerebral sulci pattern on MR images is useful and important when locating the space occupying lesion of the brain.
Brain ; Corpus Callosum ; Magnetic Resonance Imaging*

PURPOSE: Choroid Plexus papilloma is a rare intracranial neoplasm that is most commonly found in the trigone of the lateral ventricle in children or in the fourth ventricle in adult. Extraventricular extension of choroid plexus papilloma has been rarely reported within the cerebellopontine angle (CPA) cistern. Authors report two cases of choroid plexus papilloma in the posterior fossa seen on magnetic resonance imaging (MRI). MATERIALS AND METHODS: MRI findings of two cases of choroid plexus papilloma in posterior fossa were retrospectively reviewed. RESULTS: In the first case, the tumor was in the fourth ventricle and extended to the left CPA cistern via the foramen of Luschka. In the second case, the tumor presented as an expansile mass of the of fourth ventricle and right lateral recess. Multiple signal voids of low intensity due to prominent feeding vessels and calcifications within the tumors were noted. CONCLUSION: This report demonstrates MR findings of choroid plexus papilloma in the posterior fossa with the brief review of the literatures.
Adult ; Brain Neoplasms ; Cerebellopontine Angle ; Child ; Choroid Plexus* ; Choroid* ; Fourth Ventricle ; Humans ; Lateral Ventricles ; Magnetic Resonance Imaging ; Papilloma, Choroid Plexus* ; Retrospective Studies

The CT findings of the acute cerebral infarction are well known. However the CT findings of early stroke within 24 hours of the onset have not been sufficiently reported. The purpose of this study is to evaluate early acute cerebral infarction on CT within 24 hours after ictus. The early and accurate CT diagnosis could lead to the appropriate therapy and improved outcome of the patients. Authors retrospectively analyzed 16 patients with early acute cerebral infarction. Acute cerebral infarction was confirmed by follow-up CT in 11 patients, SPECT in 4 patients, and MRI in 1 patient. The CT findings of early acute cerebral infarction include effacement of cortical sulci or cistern (n=16, 100%), hyperattenuation of MCA (n=3), obscuration of lentiform nucleus (n=6), loss of insular ribbon (n=6) and subtle low density in hemisphere (n=5). The most frequent findings was effacement of cortical sulci in our study, and it was though to be the most important sign of early acute cerebral infarction.
Cerebral Infarction* ; Corpus Striatum ; Diagnosis ; Follow-Up Studies ; Humans ; Magnetic Resonance Imaging ; Retrospective Studies ; Stroke ; Tomography, Emission-Computed, Single-Photon

No abstract available.

The utilization of CT-guided fine needle aspiration biopsy of bone has been the subject of considerable interest, since the introduction of the CT scanning. The CT-guided needle biopsy of 11 consecutive patients with avariety of "Etiology Unknown Spinal Disorders" resulted in a 100% yield of positive tissue diagnosis without significant complicaitons. The main advantage of CT guidance is the continuous direct observation of the needletip position in relation to the target volume, the more precise sampling from smaller and deeper lesion is another advantage. We are confident that localization of pathology by CT is the most accurate method for perform ingbiopses, and thus replaces the conventional ways of approaches and this could be utilized on the other organbiopsy in the future.
Biopsy ; Biopsy, Fine-Needle ; Biopsy, Needle ; Diagnosis ; Humans ; Methods ; Pathology ; Tomography, X-Ray Computed

No abstract available.
Esophageal Atresia* ; Tracheoesophageal Fistula*

MR finding of melanoma shows peculiar signal intensity based on paramagnetic effect of melanin or intratumoral hemorrhage, which displays decreased T1 and T2 relaxation times in many cases. Authors report MR findings in two cases of intracranial metastatic melanoma, which is pathologically confirmed by operation.
Hemorrhage ; Magnetic Resonance Imaging* ; Melanins ; Melanoma* ; Relaxation

Small cell osteosarcoma is a rare form of osteosarcoma and the histological differential diagnosis from other small round cell tumors (SRCTs) is difficult. The immunohistochemical stain for MIC2 has been considered an useful diagnostic marker for Ewing's sarcoma and primitive neuroectodermal tumors but recently, other SRCTs such as malignant lymphoma and embryonal rhabdomyosarcoma also showed positive reaction. Therefore, the usefulness of MIC2 must still be proven. We experienced a case of small cell osteosarcoma of the mandible in a 25-year-old man. Histologically, the tumor consisted of small round cells that resembled those of Ewing's sarcoma. Immunohistochemically, the tumor cells expressed diffuse strong positive reaction for MIC2 gene products. However, the scanty foci of lacy osteoid material between the tumor cells seemed to be diagnostic of osteosarcoma. The histologic and immunohistochemical findings of this case suggest close relationship between small cell osteosarcoma and Ewing's sarcoma.
Adult ; Diagnosis, Differential ; Humans ; Lymphoma ; Mandible ; Neuroectodermal Tumors, Primitive ; Osteosarcoma* ; Rhabdomyosarcoma, Embryonal ; Sarcoma, Ewing*