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H Ishijima

Publications and source records attributed to H Ishijima.

At least 19 recordsLinked to original sources
PubMed2001

FDG PET of primary benign and malignant bone tumors: standardized uptake value in 52 lesions.

PURPOSE: To evaluate the standardized uptake value (SUV) of 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG) at positron emission tomography (PET) in the differentiation of benign from malignant bone lesions. MATERIALS AND METHODS: Fifty-two (19 malignant, 33 benign) primary bone lesions were examined with FDG PET prior to tissue diagnosis. The SUVs were calculated and compared between benign and malignant lesions and among histologic subgroups that included more than four cases. RESULTS: There was a statistically significant difference in SUV between benign (2.18 +/- 1.52 [SD]) and malignant (4.34 +/- 3.19) lesions in total (P =.002). However, giant cell tumors (n = 5; SUV, 4.64 +/- 1.05) showed significantly higher SUV than chondrosarcomas (n = 7; SUV, 2.23 +/- 0.74) (P =.036, adjusted for multiple comparisons) and had no statistically significant difference in SUV compared with osteosarcomas (n = 6; SUV, 3.07 +/- 0.96) (P =.171). There was no statistically significant difference in SUV between fibrous dysplasias (n = 6; SUV, 2.05 +/- 0.98) and osteosarcoma (P =.127) or chondrosarcomas (P =.667). Although the number of cases was small, three chondroblastomas, one sarcoidosis, and one Langerhans cell histiocytosis showed levels of FDG accumulation as high as that of osteosarcomas. CONCLUSION: Radiologists should be aware of the high accumulation of FDG in some benign bone lesions, especially histiocytic or giant cell-containing lesions. Consideration of histologic subtypes should be included in analysis of SUV at FDG PET of primary bone tumors.

Adult↗
PubMed1999

Pulsed-Field Ionization Zero-Kinetic-Energy Photoelectron Spectra of Ar(2).

The pulsed-field ionization (PFI) zero-kinetic-energy (ZEKE) photoelectron spectra of Ar(2) were measured between 117 000 cm(-1) (14.5 eV) and 128 300 cm(-1) (15.9 eV) using the penetrating field technique and synchrotron radiation at resolutions of up to 1 meV. The A(2)Sigma(+)(1/2u) ground state and B(2)Pi(1/2g) and C(2)Pi(3/2u) excited states were assigned to those spectra. The first adiabatic ionization potential of Ar(2) was determined to be 14.4572 +/- 0.0007 eV. A Le Roy-Bernstein plot and a Birge-Sponer plot were used to determine the dissociation limit of the A(2)Sigma(+)(1/2u) ground state. The vibrational level of the C(2)Pi(3/2u) excited state was observed for the first time. The effective lifetime for high-n Rydberg states converging on the vibrational levels of the C(2)Pi(1/2u) excited state is estimated to be shorter than those of the A(2)Sigma(+)(1/2u), B(2)Pi(1/2g), and C(2)Pi(3/2u) states, because the spectrum could not be observed on the PFI-ZEKE experiment. The threshold photoelectron-photoion coincidence spectra of Ar(2) were also measured and compared with the spectra obtained from the PFI-ZEKE experiment. Copyright 1999 Academic Press.

Journal Article↗
PubMed1998

An autopsy case of systemic hemangiomatosis with honeycomb-like liver and focal splenic sarcomatoid changes.

An unusual autopsy case of systemic hemangiomatosis associated with honeycomb-like liver and splenic sarcomatoid changes is presented. The patient suffered from high-output ventricular heart failure secondary to hepatic arteriovenous shunting with hepatic failure, ending fatally due to disseminated intravascular coagulation and pulmonary bleeding. Postmortem examination revealed the characteristic distribution of vasoformative tumors presenting in the hematopoietic system including the liver, bone marrow, and spleen, with the liver appearing characteristically honeycomb-like. While these vasoformative tumors were mostly benign-appearing, partial shifts toward sarcomatoid change were observed in the splenic lesions.

Angiomatosis↗
PubMed1997

Correlation of T1 and T2 relaxation rates in normal bone-marrow water with serum ferritin concentration.

PURPOSE: This study was made to clarify the paramagnetic effect of iron stored in the hematopoietic tissue of bone marrow. MATERIAL AND METHODS: The T1 and T2 relaxation times of bone-marrow water in the L1-3 vertebrae of 20 healthy individuals were measured by MR imaging with a 1.5 T magnet. The chemical shift misregistration effect was used to isolate the bone-marrow water. The results were compared with the serum ferritin concentration. RESULTS AND CONCLUSION: Although no correlation between the T1 relaxation rate of the water fraction and the serum ferritin concentration was evident, the T2 relaxation rate of the water fraction showed strong linear correlation with the serum ferritin concentration (r = 0.87, p < 0.0001). Thus, T2 of bone-marrow water accurately reflects the amount of iron in normal bone marrow. This finding may be useful in the evaluation of the characteristics of hematopoietic tissue in bone marrow.

Adult↗
PubMed1997

Compulsory superselective arterial embolization in hypovascular local hepatic tumor ablation. Microballoon coaxial catheterization.

We performed compulsory superselective transcatheter arterial embolization on local hypovascular liver metastases under balloon occlusion using a 1-mm (3 F) coaxial microballoon catheter in 2 cases. One case was a metastasis from breast cancer (maximum diameter 5.5 cm) at segment 7. The other case comprised metastases from rectal cancer (maximum diameter 8 cm) at segments 7 and 8. Absolute ethanol (50%) mixed with Lipiodol (50%) was used for embolization. No major treatment-related complications occurred. No local recurrence was observed in either case in follow-up CT and MR studies of up to 16 and 9 months respectively. This technique may thus be applied as an alternative to surgical resection in the treatment of local hypovascular liver tumors.

Aged↗
PubMed1996

Distinguishing between cystic teratomas and endometriomas of the ovary using chemical shift gradient echo magnetic resonance imaging.

The purpose of this study was to evaluate the efficacy of chemical shift gradient echo magnetic resonance imaging (MRI) in distinguishing between cystic teratomas and endometriomas of the ovary, using a 1.5T magnet. The study included 22 patients with 31 ovarian lesions (15 cystic teratomas and 16 endometriomas), which showed high signal intensity on T1-weighted spin echo images. Chemical shift gradient echo images with three different echo times (TE = 2.5, 4.5 and 6.5 ms) were obtained in all cases. Indices were calculated on the basis of the signal intensities of lesions on the chemical shift gradient echo images. All endometriomas had signal intensity indices of less than 2.1, while all cystic teratomas had signal intensity indices of 18.1 or greater. Chemical shift gradient echo imaging is an alternative method that is useful and simple for distinguishing between cystic teratomas and endometriomas of the ovary.

Diagnosis, Differential↗
PubMed1996

Water fraction of lumbar vertebral bone marrow estimated from chemical shift misregistration on MR imaging: normal variations with age and sex.

OBJECTIVE: Our objective was to use the chemical-shift misregistration effect of MR imaging to measure the variation in the water fraction in vertebral bone marrow with respect to patient age and sex. SUBJECTS AND METHODS: We examined prospectively 211 subjects (5-84 years old; 108 male and 103 female subjects) who had no history of hematologic disorders. We obtained midsagittal proton density-weighted spin-echo images (2500/22 [TR/TE]) with a narrow sampling bandwidth (6250 Hz). Misregistered signals from lipid protons of 6-10 mm (upward shift in the readout direction) were obtained with the chemical-shift effect. By measuring the mean signal intensities of the water voxels and the water-plus-lipid voxels, we calculated a region of interest in each vertebral body for L1 to L3. The water fraction of bone marrow was then calculated as 100 x (signal intensity of water voxels/signal intensity of water-plus-lipid voxels). Individual water fractions were calculated from the average values for the water fractions of the L1-L3 bodies. RESULTS: In the male subjects, the water fraction showed a rapid decrease in the older patients in the 5- to 34-year-old group. (Mean water fractions for male patients who were 5-14, 15-24, and 25-34 years old were 75.2%, 69.0%, and 53.7%, respectively.) For male patients more than 25 years old, the water fraction remained almost constant (approximately 50%). In female subjects who were 5-44 years old, the water fraction exceeded 69% and remained almost constant. However, the water fraction rapidly decreased in women more than 45 years old. (Mean water fractions for female patients who were 35-44, 45-54, and 55-64 years old were 70.9%, 61.1%, and 49.7%, respectively.) A comparison between male subjects and female subjects showed that the water fraction for women who were 25-54 years old exceeded the water fraction for men in the same age group (25-34 years old, p < .0001; 35-44 years old, p < .001; 45-54 years old, p < .05). CONCLUSION: MR imaging showed that male and female subjects convert hematopoietic marrow to fatty marrow in the lumbar vertebral bodies in significantly different ways. The data obtained for the normal water fraction of bone marrow may prove useful for evaluating diseases that affect marrow.

Adolescent↗
PubMed1988

[The efficacy of combined use of 1 alpha-hydroxyvitamin D3 with calcium supplements in the treatment of osteoporosis].

Synthetic analogue of active vitamin D metabolite, 1 alpha (OH) D3, has been widely used in the treatment of osteoporosis. However, the most effective method of treatment is yet to be established. Importance of calcium supplement to improve the calcium metabolism in osteoporosis is also reported by many authors. We have studied the combined effects of 1 alpha (OH)D3 with calcium supplement in preventing progressive decrease of bone mass in patients with osteoporosis. Sixty-six cases of postmenopausal and senile osteoporosis were divided into two groups: one treated with calcium alone 1,000 mg a day and the other treated with calcium 1,000 mg and 1 alpha (OH)D3 0.5 microgram a day, and both groups were followed for 24 months. Bone mass was evaluated by microdensitometry of the roentgenograms of the second metacarpal bone. The results revealed that the combined use of 1 alpha (OH)D3 with calcium has a significantly more favorable effect than the use of calcium alone in preventing bone loss. Therefore, 1 alpha (OH)D3 with calcium is useful in the treatment of osteoporosis. The conclusion would be further confirmed with longer term study and a more accurate method of measuring bone mass.

Aged↗
PubMed1975

[An interhemispheric subdural abscess (author's transl)].

A subdural abscess which is cinfined to the interhemispheric space alone, which does not extend over the convexity is rare. This is a specific form and is a complication of a common intracranial subdural abscess. It is of great practical importance to determins this uncommon location, and cerebral angiography is most useful. Multiple trephinations or craniotomy for exploration and evacuation must be performed near the midline. A 20 year old female was in a comatose state on admission. There was a flaccid paralysis of the right lower extremity and a dilated left pupil. Examination of the eyegrounds showed bilateral choked discs. Left cerebral angiography revealed the proximal pericallosal artery to be shifted to the right side and the callosomarginae artery was displaced from the midline parallel to the distal pericallosal artery. Although 20 ml of pus was evacuated through the parietal burr hole, which was located a bout 2.5 cm from the midline, she died. At autopsy, a subsural abscess was found in the interhemispheric space. It extended from the frontal pole to the occipital and had a thick membrane which adhered firmly to the falx medially. We could find no other subdural nor intracerebral pus collections. The left cerebral hemisphere was edematous. The superior sagittal sinus had a thick wall and was almost occluded. This dural sinus thrombophlebitis may have developed into the interhemispheric subdural abscess. It is emphasized that this uncommon location for subdural abscess poses a specific problem in clinical practice.

Adult↗
PubMedDate not supplied

Intact PTH-producing hepatocellular carcinoma treated by transcatheter arterial embolization.

We report a case of hepatocellular carcinoma with hypercalcemia. There was no evidence of bone metastasis or increase in parathyroid hormone-related protein. The serum level of intact parathyroid hormone (intact PTH) was very high, and the results of the hepatic venous sampling suggested that the tumor produced intact PTH. Transcatheter arterial chemoembolization effectively controlled the humoral hypercalcemia.

Aged↗
PubMedDate not supplied

Partial renal embolization for pediatric renovascular hypertension secondary to fibromuscular dysplasia.

We report a 7-year-old boy with renovascular hypertension showing multiple stenoses and microaneurysms of the dorsal branch of the left renal artery caused by fibromuscular dysplasia. Hypertension was successfully treated with transcatheter alcohol and gelatin sponge embolization of the dorsal branch and its distribution. The vertebral branch remained intact. No severe complication was encountered. Loss of renal function by renal scintigraphy was minimal. The patient remains asymptomatic at 1 year.

Child↗