Biomedical subjects

J Watarai

Publications and source records attributed to J Watarai.

At least 37 records · Page 2Linked to original sources

PubMed1998

Retrospective multi-institutional study of radiotherapy for intracranial non-germinomatous germ cell tumors.

The treatment outcome of 24 patients with pathologically-proven non-germinomatous germ cell tumor was retrospectively investigated to determine the effectiveness of radiotherapy. The patients were divided into three groups as follows: group 1, five patients with mature teratoma with or without germinoma; group 2, six patients with immature teratoma with or without germinoma; group 3, 13 patients with other highly malignant tumors. The overall actuarial survival and relapse-free rates at 5 years were 82% and 59%, respectively, with a median follow-up period of 62 months. The actuarial relapse-free rate at 5 years was 100% for group 1, 63% for group 2 and 44% for group 3. There was no difference in the relapse-free rates between total resection and partial resection. Usage of chemotherapy was adversely related to survival probably due to selection bias. No local failure was observed with 10 Gy or more for group 1,40 Gy or more for group 2 and 54 Gy or more for group 3. In groups 1 and 2, there was no spinal relapses without craniospinal irradiation. In group 3, three of eight patients who did not receive craniospinal irradiation and none of five patients who received craniospinal irradiation experienced spinal relapse. In conclusion, highly malignant GCTs show a high incidence of spinal metastasis and craniospinal irradiation may reduce the risk of spinal metastasis. Radiation dose and volume are to be determined according to the histopathological aggressiveness.

Adolescent↗

PubMed1998

[Brain magnetic resonance imaging findings in two cases of Hunter's syndrome].

Magnetic resonance (MR) imaging findings in two cases of Hunter's syndrome [mucopolysaccharidosis (MPS) type II A] are reported. The first case is a 15-year-old boy in whom the diagnosis of Hunter's syndrome was made at 2 years of age on the basis of increased glycosaminoglycans in the urine, developmental delay, characteristic faces, joint contraction, family histories, and radiological characteristics including oar-like deformed ribs and dysplasia of lumbar vertebrae. MR images showed marked enlargement of the lateral ventricles and third ventricle. The cerebral cortical sulci were diffusely dilated. Abnormal intensity lesions in the lateral part of the lentiform nucleus, the subcortex of the insula, the pons, and the right thalamus were seen. Diffuse hyperintensity throughout the periventricular white matter is also seen on T2-weighted images. The second case is a 3-year-old boy, born at immature delivery. At 2 months of age, he was admitted to a pediatric department because of liver dysfunction, inguinal hernias and umbilical hernia. The diagnosis of Hunter's syndrome was made by developmental delay, gargoylism, joint contraction, kyphosis, and biochemical investigation of urine. Urinary glycosaminoglycans significantly increased. Skeletal radiography showed dysplasia of the lumbar vertebrae and acetabulum. T1-weighted MR images demonstrated numerous hypointense spots in the corpus callosum and the cerebral white matter, presumably suggesting large perivascular spaces. Multiple cystic changes appeared to be hyperintense on T2-weighted images. Numerous linear hyperintense lesions were visible in the corona radiata. Patchy areas of hyperintense areas were seen, more prominent in the parietal lobes. Neuropathological examinations in cases of Hunter's syndrome have previously shown marked dilatation of ventricular system, large perivascular spaces secondary to mucopolysaccharide storage, demyelination and gliosis in the white matter and so forth. MR findings correlated well with previously reported neuropathological findings. MR study is not only useful for diagnosing Hunter's syndrome but also helpful to follow the pathological status.

Adolescent↗

PubMed1998

[Superficial siderosis appeared in a case of suprasellar embryonal carcinoma].

A case of superficial siderosis that appeared in a case of suprasellar embryonal carcinoma is reported. A 24-year-old man presented polydipsia and vertigo. MRI revealed a suprasellar tumor. The tumor contained high intense spots on T1-weighted images, suggesting intratumoral hemorrhage. He underwent a surgery, which proved it as embryonal carcinoma pathologically. Cerebrospinal fluid was xanthochromic at surgery, suggesting terminal hemorrhage. After surgery, he received a total dose of 56 Gy of irradiation. Tumor decreased in size and symptoms improved. However, he presented occipital headache 7 months after surgery. MRI showed disseminated tumors in the subarachnoid spaces. He received irradiation for the whole spine and adjuvant chemotherapy. During treatment, MRI demonstrated low signals on the surface of the brain stem, suggesting the superficial siderosis. The lesions spread to the surface of the cerebellum and tentorium cerebelli. Superficial siderosis is characterized by the deposition of hemosiderin in the leptomeninges, cranial nerves and spinal cord. The etiology of the hemosiderin deposition is thought to be chronic or recurrent bleeding into subarachnoid space. Experimentally, similar lesions have been produced in the animals following intrathecal injection of blood or hemolysed red cells. In the literature, MRI demonstrated a rim of marked hypo-intensity on T2-weighted images, consistent with hemosiderin deposits, on the surface of cerebellum and brain stem. Gradient-echo sequences have been more sensitive than T2-weighted images of spin echo sequences. In the present case, the superficial siderosis seems to be due to chronic tumoral hemorrhage. This phenomenon could be related to chemotherapy using CDDP and etoposide.

Adult↗

PubMed1997

Thrombophlebitis of the inferior vena cava involving the retroperitoneum with Crohn's disease: MR demonstration.

We present a case of thrombophlebitis of the inferior vena cava (IVC) with Crohn's disease after intestinal perforation and prolonged indwelling of a catheter in the IVC. Magnetic resonance imaging demonstrated abnormal thickening and enhancement of the IVC wall. In addition, IVC thrombus formation was shown. The abnormal enhancement extended from the wall in the pericaval tissue and into the retroperitoneum, and regressed as the Crohn's disease subsided.

Adult↗

PubMed1997

Accessory lobe of the liver mimicking a mass in the left adrenal gland. A case report.

An accessory lobe of the liver is a rare anomaly which we have diagnosed in a patient by CT. The lesion appeared as a soft-tissue-density mass with the same density as the liver and attached to the liver. Radionuclide liver scintigraphy helped to confirm the diagnosis. The object of this report is to draw attention to this rare entity since it can cause diagnostic confusion.

Adrenal Gland Neoplasms↗

PubMed1997

Use of carbon dioxide microbubble-enhanced sonographic angiography for transcatheter arterial chemoembolization of hepatocellular carcinoma.

OBJECTIVE: Our objective was to determine the usefulness of sonographic angiography with carbon dioxide microbubbles during transcatheter arterial chemoembolization for hepatocellular carcinoma. SUBJECTS AND METHODS: Thirty-four patients with hepatocellular carcinoma underwent sonographic angiography during transcatheter arterial chemoembolization. Digital subtraction angiography failed to reveal tumors in 27 patients. Tumor stain became obscure on digital subtraction angiography after the catheter was inserted into distal branches in seven patients. Sonographic angiography was performed after injection of carbon dioxide microbubbles into the hepatic artery selected for transcatheter arterial chemoembolization. RESULTS: In angiographically undetectable hepatocellular carcinomas, sonographic angiography revealed tumor vascularity in 17 patients in whom transcatheter arterial chemoembolization was then performed. For the two patients who underwent a second transcatheter arterial chemoembolization, the existence of alternative feeding vessels was confirmed by sonographic angiography. In the remaining 10 patients, tumor vascularity was not seen on sonographic angiography; percutaneous ethanol injection therapy was then performed. Sonographic angiography clearly revealed tumor vascularity in patients in whom staining became obscure on digital subtraction angiography after the catheter was inserted into a peripheral branch of the hepatic artery. In all 24 patients who underwent transcatheter arterial chemoembolization, sonographic angiography was useful for determining the artery suitable for transcatheter arterial chemoembolization and for monitoring tumor perfusion in the selected artery. CONCLUSION: Sonographic angiography can be used to determine not only the therapeutic strategy for treatment of hepatocellular carcinoma but also whether the tumor is supplied by the artery selected for transcatheter arterial chemoembolization, especially when the tumor is not revealed by digital subtraction angiography.

Aged↗

PubMed1997

[Evaluation of single photon emission computed tomography of tumors in the head and neck with technetium-99m MIBI].

SPECT using 99mTc-MIBI was performed in patients with tumors in the head and neck in order to determine 99mTc-MIBI uptake in tumors and to evaluate the efficacy of 99mTc-MIBI imaging in the assessment of treatment response. A MIBI uptake index was calculated as the ratio of average counts/pixel in the tumor to average counts/pixel in the homologous contralateral side. Eighteen of 19 (95%) of the cases had increased MIBI uptake in the tumor on early images, and 8 of 14 (57%) of the cases had increased uptake of the tumor on delayed images. MIBI uptake was related to the size of the tumor. Only 6 of 25 of cervical lymph node metastases were detected by 99mTc-MIBI SPECT. In the tumors evaluated before and after radiotherapy, the superiority of 99mTc-MIBI SPECT over MRI was not obtained, but there was a tendency for MIBI-index to decrease after radiotherapy.

Adult↗

PubMed1997

[Central nervous system involvement of leukemia and systemic lymphoma in children: CT and MR findings].

The purpose of this paper is to retrospectively evaluate CT and MR findings of central nervous system (CNS) involvement of leukemia and systemic lymphoma in children. Over a 12-year period, sixty-five patients with leukemia and fifteen patients with systemic lymphoma underwent cerebral CT and/or MR imaging. Nine patients (11.3%) were diagnosed as CNS involvement of leukemia and lymphoma. The diagnostic criteria of CNS involvement were as follows; 1) Histological proof was confirmed by surgery, 2) Tumor cells were found in the cerebrospinal fluid examinations, 3) Increase in size of the lesion during observation without specific treatment, and 4) Response to the treatment for leukemia or lymphoma. All of nine patients fulfilled more than two criteria of 1)-4). The CT and MR abnormalities in these patients were correlated with the findings of histology, cerebrospinal fluid cytology, and/or treatment. The age of the patients ranged from 0 to 15 years old. They consisted of 6 boys and 3 girls. The CT examinations were performed before and after contrast administration. MR examinations were performed on a 1.5-T unit, and T1-weighted, T2-weighted, and proton density-weighted images were obtained using spin-echo or fast spin-echo sequences. Tumor masses were present in seven with leukemia (acute lymphoblastic leukemia 4; acute myeloblastic leukemia 1; acute promyelocytic leukemia 1; acute monocytic leukemia 1), and in two with malignant lymphoma. On the CT scan, tumor masses were hyperdense with contrast enhancement. On the MR images, their signals were variable. In all of nine patients, tumor masses were contiguous with a meningeal surface. Postcontrast T1 weighted images were valuable in demonstrating meningeal infiltration. Tumoral hemorrhage was found in two patients. In a patient with tumor at the superior sagittal sinus, venous infarct was observed. CNS leukemic and lymphomatous masses are almost hyperdense on the CT and they are characteristically contiguous with a meningeal surface. MR imaging was valuable in demonstrating meningeal infiltration. Findings of CT and MR imaging, cerebrospinal fluid examinations, and response to the treatment are useful in the differentiation of CNS involvement of leukemia and lymphoma from other lesions such as infectious diseases and leukoencephalopathy.

Adolescent↗

PubMed1996

Infantile choriocarcinoma: a case report with MRI, angiography and bone scintigraphy.

Infantile and maternal choriocarcinoma is a very rare disease. We report a case with the characteristic clinical features of infantile choriocarcinoma: developing anemia, hemorrhagic liver tumors, rapid progression to death and maternal choriocarcinoma. Bone scintigraphy showed increased uptake by the liver tumors. In this case there were two possible primary sites: the placenta of this pregnancy and a hydatidiform mole that had been present 2 years previously.

Angiography↗

PubMed1996

Chemoembolization of head and neck cancer with carboplatine microcapsules.

Fourteen patients with malignant tumor in the head and neck region were treated with infusion of carboplatine microcapsules (CBDCA-mc) via percutaneous super-selective catheterization. A microcatheter was advanced into a feeding artery using a coaxial catheter system. Eleven patients had over 30% reduction of the tumor size on CT within 1 month after embolization. Twelve patients had an increased amount of low attenuation tissue in the tumor on CT after embolization, suggesting increased necrosis in the tumor. No definite hematologic toxicity was found. A majority of patients complained of moderate pain in the embolized region immediately after embolization, easily relieved by i.v. analgesics. Chemoembolization using CBDCA-mc may be an effective therapeutic modality in advanced cases of head and neck cancer.

Aged↗

PubMed1996

The CT findings of pulmonary sarcoidosis.

We analyzed the CT findings in 35 patients with pulmonary sarcoidosis. Twenty-seven patients had biopsy-proven sarcoidosis; in eight patients the diagnosis was made clinically. In all the 35 patients, 10-mm collimation scans were available. In seven patients, high-resolution CT was also obtained. Twenty-eight patients had lymphadenopathy associated with pulmonary infiltration, two patients had pulmonary infiltration without lymphadenpathy, five patients had lymphadenopathy alone. The most frequent parenchymal features on CT were small nodules (100%) and irregularly thickened bronchovascular bundle (90%). Other frequent CT findings were pleural or subpleural thickening (83%), septal lines (73%) and ground-glass attenuation (63%). In all cases, small nodules were associated with other lesions. The authors conclude that in patients with sarcoidosis, CT is a valuable technique to visualize the findings in the pulmonary parenchyma characteristic enough to allow confident diagnosis. While high-resolution CT is superior in the assessment of linear opacities and cysts, conventional CT is superior in demonstrating small nodular opacities. We believe that both should be combined in the examination of patients with sarcoidosis.

Adult↗

PubMed1996

Surgical treatment for caustic ingestion injury of the pharynx, larynx, and esophagus.

A 45-year-old female drank Sunpole (9.5% hydrochloric acid), an acidic toilet cleaner, in a suicide attempt. Notwithstanding intravenous administration of steroids and bougienage dilation, corrosive changes progressed. The patient underwent surgery for severe caustic ingestion injury of the pharynx, larynx, and esophagus. Colon bypass surgery from the left vallecula to the stomach was performed. Excellent results, both in deglutition and phonation, were obtained. We report on the case and stress several points of importance in dealing with severe caustic ingestion injuries.

Caustics↗

PubMed1996

[MRI abnormalities of the brain in neurologic complications following treatment of cancer in children].

During a 3-year period, 6 of 50 children with systemic malignacies developed neurologic complications such as hemiparesis, convulsions and loss of consciousness. The children consisted of 1 boy and 5 girls, from 3 to 12 years old, 3 with acute lymphoblastic leukemia and 3 with malignant lymphoma. Four patients received induction treatment that included intravenous administration of L-asparaginase and/or intrathecal administration of methotrexate. One patient received induction treatment and consolidation treatment that included intravenous administration of L-asparaginase. One patient received induction and consolidation treatment, and the protocol for peripheral blood stem cell transplantation. Laboratory examinations revealed coagulation dysfunction in 3 patients treated with L-asparaginase and 1 patient with disseminated intravascular coagulation (DIC). Magnetic resonance imaging (MRI) was performed on a 1.5-T unit, using spin-echo or fast spin-echo sequences. T1-weighted, T2-weighted, and proton density-weighted images were obtained in the axial and/or coronal plane (section thickness, 4 mm; inter-section gap, 2 mm). MRI was initially performed within 36 hours after the onset in all patients, and follow-up MRIs were performed for 6 months. MRI showed lesions involving the cortex and subcortex in 4 patients with coagulation dysfunction. In 2 of these 4 patients, Gd-enhanced T1-weighted images showed contrast enhancement in the surface of the gyrus, suggesting focal vascular stasis. Serial MRI revealed nearly complete resolution of the lesions. Symptoms were relieved in every case. The lesions on MRI were presumed to be due to venous thrombosis related to the coagulation dysfunction caused by L-asparaginase or DIC. On the other hand, in 2 patients with onset after intrathecal administration of high-dose methotrexate and cytarabine, MRI revealed multiple lesions involving the centrum semiovale and periventricular white matter. No Gd-enhancement of the lesion was detected. This MRI finding was consistent with leukoencephalopathy. As time passed, the symptoms improved completely, and the lesions became better demarcated. MRI is useful for differentiating lesions related to coagulation dysfunction from leukoencephalopathy.

Adolescent↗

PubMed1995

Normal variations of the temporal bone on high-resolution CT: their incidence and clinical significance.

We evaluated normal variations of the temporal bone on high-resolution computed tomograms (HR-CTs) and investigated their incidence. HR-CTs of the temporal bones of 325 patients were retrospectively reviewed. Six groups of variants, which were considered important for presurgical planning, were evaluated on HR-CTs. These included: (1) an incomplete bony covering of a high-positioned jugular bulb; (2) severe asymmetry of the jugular foramen; (3) an anteriorly located sigmoid sinus; (4) a deep sinus tympani; (5) a large internal auditory canal; and (6) a large cochlear aqueduct. The frequency of the variations were as follows: (1) 2.4%; (2) 4.0%; (3) 1.6%; (4) 5.9%; (5) 2.3%; and (6) 3.0%. Bilateral involvement with variation (4), (5) and (6) was frequently seen. Normal anatomical variations of the temporal bone are therefore not rare and awareness of the possible variants is necessary before surgery of the inner ear, middle ear and posterior fossa.

Adolescent↗

PubMed1995

[Vasoreactivity of normal brain tissue in cases of arteriovenous malformations--evaluation by 123I-IMP SPECT using acetazolamide].

Arteriovenous malformations (AVMs) are usually associated with diminished cerebral blood flow (CBF) in the parenchyma surrounding AVMs because of the steal phenomenon. Vasoreactivity in the parenchyma surrounding AVMs may change because of ischemia and abnormal hemodynamics. The aim of this study was to investigate vasoreactivity in parenchyma surrounding AVMs. Quantitative single-photon emission computed tomography using N-isopropyl-p-I-123 iodoamphetamine (IMP-SPECT) was performed before and after intravenous administration of acetazolamide (Diamox). Diamox is a potent cerebral vasodilator which causes tissue acidosis, and IMP-SPECT was performed 10 min after intravenous infusion of a 1g dose. The subjects were 8 patients with AVMs. The AVM was in the frontal lobe in 3 patients, the temporal lobe in 1 patient, the lateral ventricle in 1 patient, the midbrain in 1 patient, the basal ganglionic region in 1 patient, and the vein of Galen in 1 patient. A rotating gamma camera with two heads was used to perform SPECT. IMP was injected into an arm vein, and a 5-min period of blood withdrawal, 1 ml/min, was started simultaneously from a small catheter placed in the radial artery. Kuhl's method was used to quantify cerebral blood flow (CBF). Multiple contiguous 6-pixel-diameter region of interest (ROI) circles along the cerebral cortex and cerebellar hemisphere were used, and ROIs which included the AVM nidus, draining veins or infarctions were excluded from the study. Vascular territories containing arteries feeding the AVM were defined as near-ROIs on SPECT, and all other ROIs were defined as far-ROIs. (ABSTRACT TRUNCATED AT 250 WORDS)

Acetazolamide↗

PubMed1995

[Chemoembolization of maxillary carcinoma via the superficial temporal artery using a coaxial catheter system].

To perform chemoembolization of maxillary carcinoma, an approach through the superficial temporal artery was applied. A 5-French guiding catheter was advanced into the maxillary artery. The microcatheter was advanced into the terminal portion of the maxillary artery through the guiding catheter, and then carboplatine microcapsules were infused into the feeding artery. Chemoembolization was performed twice in one patient and three times in another. This new method will make it feasible to repeat chemoembolization in patients with head and neck tumors.

Aged↗

PubMed1994

[Thallium-201 single photon emission computed tomography in the evaluation of therapeutic response for brain tumors].

To evaluate the effectiveness of radiation and chemotherapy of malignant brain tumors, 201TlCl-SPECT (Tl-SPECT) was compared with CT and MRI. The subjects were 14 patients with malignant brain tumors; 12 malignant astrocytomas, 1 medulloblastoma and 1 malignant lymphoma. Tl-SPECT was performed before and immediately after the therapy. On the Tl-SPECT, count ratio (Tl-index) of tumor to normal brain tissue was measured. To evaluate the size of tumor, CT or MRI was performed before and immediately after the therapy, and 1-2 months after the therapy. The change of Tl-index immediately after therapy was compared with the change of the size of tumor. Though the change of Tl-index did not correlate with the change of tumoral size immediately after therapy, it correlated with the change of tumoral size 1-2 months after the therapy, i.e., it was thought that Tl-index reflected the change of tumoral size 1-2 months after the therapy. Tl-SPECT will be feasible for the evaluation of the effectiveness of the therapy for malignant brain tumors, because it reflects the effectiveness of the therapy earlier than CT or MRI.

Adult↗

PubMed1993

[Usefulness of 201T1C1-SPECT in the evaluation of radiation and chemotherapy for brain tumors].

We investigated the usefulness of Thallium-201 chloride single photon emission computed tomography (T1-SPECT) in the evaluation of radiation and chemotherapy for brain tumors. The subjects were 9 cases (10 tumors) of malignant astrocytomas. T1-SPECT was performed before and immediately after irradiation and/or intraarterial infusion of ACNU. In 5 of 10 tumors, T1-index already changed 1 or 2 months before tumor size changed on the CT. Our results suggested that T1-SPECT was useful for evaluating the viability of tumor.

Aged↗