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We developed a multiple side-holed sheath introducer that can also be used as a catheter for aortography before selective arteriography of the pelvic organs or lower extremities, as an alternative to straight or pig-tail catheters, which were formerly used for aortography. Aortography using the multiple side holed sheath introducer provided good detection of arteries in 100% of 10 cases, without any complications or difficulties. Thus, the present sheath introducer can replace straight or pig-tail catheters, resulting in the more economical use of one catheter prior to selective arteriography.

Purpose: To evaluate the efficacy of transcatheter arterial embolization for pulmonary arteriovenous fistula (PAVF)., Materials and Methods: Eight patients with 14 PAVFs were treated by TAE for feeding arteries. In 5 of 8 cases, detachable balloons were used, and, in 3 of 8 cases, metalic coils were used for embolization of the feeding arterial branch. Detachable balloons or a series of metalic coils were placed at the feeding artery proximal to the fistula. The diameter of detachable balloons was twice the diameter of the feeding arterial branch. The diameter of metalic coils was 1 mm larger than the diameter of the feeding artery., Results: No complications were apparent in our cases. All PAVFs were completely occuluded by the embolization of a feeding branch. One month after the procedures, the arterial oxygen pressure increased to normal values in all cases and clinical symptoms disappeared. On postcontrast CT, the fistulas treated by the embolization of a feeding arterial branch were not enhanced., Conclusion: The embolization of a feeding branch provided a radical cure for PAVFs.

We evaluated the clinical utility of 3D-CT cystography using the perspective volume rendering technique in 5 patients with disorders of the urinary bladder and prostate. Unlike the conventional orthostatic volume-rendering technique, the capability of optional visual point settlement in the urinary bladder precluded cutting a subset of acquired data for luminal inspection, and permitted observation closer to lesions. Consequently, the technique enabled the evaluation of the accurate size, shape, and relation to adjoining mucosa and the region shaded by bulky tumor. 3D-CT cystography using the perspective volume-rendering technique facilitated 3-D inspection of the bladder lumen.

MR imaging of the femoral marrow was performed in 36 patients with untreated acute myeloid leukemia (AML) and 7 patients with acute lymphocytic leukemia (ALL). The MRI appearance was classified into five patterns: 1) fatty marrow; 2) faint signal; 3) nodular pattern; 4) heterogeneous infiltration; and 5) diffuse infiltration. The MRI patterns of the femoral marrow were compared among the FAB subtypes of acute leukemia, and the MRI patterns were correlated with prognosis. All five MRI patterns were observed in the femoral marrow in adult acute leukemia, and diffuse infiltration was most commonly seen (41.9%). A completely fatty marrow was also depicted in two cases (4.7%) and faint signal in four cases (9.3%) in spite of untreated acute leukemia. The M2 subtype of AML tended to be demonstrated as a minimally abnormal MRI finding, which was significantly different from the other types of AML. The patients who showed fatty marrow or faint signal were thought to have a good prognosis, while diffuse or heterogeneous infiltration was regarded as a poor prognostic sign. However, there were some exceptions to these rules, and no significant differences were revealed in prognosis between minimally abnormal and advanced MRI patterns. We concluded that MRI of the femoral marrow could be useful in the assessment of tumor volume of adult acute leukemia, and that there were limitations to predicting prognosis on the basis of the MRI manifestations.

T1 and T2 relaxation time measurements of the femoral marrow were performed in 20 patients with acute myeloid leukemia (AML) and 9 patients with iron deficiency or other severe anemia who had shown diffuse abnormal signals on MR imaging of the femoral marrow. The ability of T1 and T2 values to differentiate between leukemic infiltration and hyperplastic hematopoietic marrow was evaluated. T1 and T2 ratios (T1 abnormal marrow/T1 normal marrow and T2 abnormal/T2 normal) were calculated, and the ratios of T1 to T2 (T1/T2) and of the T1 ratio to the T2 ratio (T1 ratio/T2 ratio) were also analyzed. Diffuse infiltrative marrows revealed prolonged T1 relaxation times in all patients with AML and other severe anemia, and it was not possible to distinguish the two groups of diseases on the basis of T1 values. The T2 relaxation times varied widely in AML, but the mean T2 value of the AML group was not statistically significantly different from that of the anemia group. There were also no significant differences in the T1 ratio, T2 ratio, T1/T2, and the T1 ratio/T2 ratio between leukemic infiltration and hyperplastic hematopoietic marrow. We concluded that measurement of T1 and T2 relaxation times was of limited clinical importance for the histological characterization of diffuse bone marrow disorders.

MR imaging of the femoral marrow was performed in 30 patients with myelodysplastic syndrome (MDS), 11 cases of which evolved to acute myeloid leukemia (AML). The MRI appearance was classified into five patterns: 1) fatty marrow; 2) faint signal; 3) nodular pattern; 4) heterogeneous infiltration; and 5) diffuse infiltration. For each type of MDS, MRI patterns of the femoral marrow were evaluated and compared with those in normal subjects as well as in patients with aplastic anemia. Signal intensity alteration, a low signal on T1-weighted SE image and a high signal on STIR image, began in the proximal femoral marrow almost symmetrically in patients with MDS. The area of abnormal signal intensity tended to gradually extend towards the distal portion of the femur as the disease progressed. MRI patterns of the femoral marrow correlated with marrow cellularity, and diffuse marrow infiltration was noted in patients with a more advanced type of MDS or with severe anemia. There were limitations to making an accurate diagnosis of the MDS type on the basis of the MRI pattern. Progression of the MRI appearance in the course of MDS was thought to be a sign suggesting evolution to AML. It was difficult to differentiate hypoplastic MDS from aplastic anemia, although the nodular pattern was commonly seen in the latter disease.

The uncomplicated bone necrosis is usually demarcated by reactive interface (RI). To analyze signal characteristics of RI, MR imaging of the hip was done using short TI IR (STIR) as well as short/long TR pulse sequences at 0.22 tesla. On STIR sequence the RI was observed as a high-signal line or ring with the shape identical to that of short TR image. The double line sign was not seen in early stage. The best explanation of high signal intensity of RI on STIR is that it has prolonged T1 and T2 secondary to high water content. It is concluded that STIR is an unique way to demonstrate RI in early osteonecrosis.