Shimpei Tada

The incidence of simple renal cyst by computed tomography

Five hundred and forty-two abdominal computed tomography (CT) scans, including the kidneys, were reviewed to investigate the incidence of simple renal cysts. Increasing frequency with age was clearly demonstrated. The incidence in patients 50 years of age and over was at least 27%. Two thirds of simple renal cysts were 2 cm or less in diameter. Cysts were usually observed as exo-endoparenchymal or endoparenchymal lesions on CT.

Color/Power Doppler Sonographic Differential Diagnosis of Superficial Lymphadenopathy Metastasis, Malignant Lymphoma, and Benign Process

Differentiation of lymph nodes as metastasis, malignant lymphoma, and benign lesions by gray scale and color/power Doppler ultrasonography has been reported. In this study we sought to determine patterns of abnormal vascularity, the relationship between diagnostic criteria and node size, and which vessel in the node was best suited for Doppler spectral analysis. Extrahilar vessels, defined as vessels entering through the lymphatic surface and not through the hilus, were also investigated.

MR imaging of adrenoleukodystrophy

SummaryWe performed MRI in 7 cases with adrenoleukodystrophy (ALD), including 3 cases with childhood ALD, 3 cases with adrenomyeloneuropathy (AMN) and one symptomatic heterozygote. The symptomatic heterozygote was the mother of the patient with AMN. High-field-strength (2.0T) MRI was used in two cases with childhood ALD. In all 3 cases of childhood ALD, MR showed widespread lesions in both cerebral hemispheres. Areas of low intensity in the diencephalon or striatum on heavily T2-weighted images at 2.0T were seen in 2 cases with childhood ALD. Cerebral lesions confined to the internal capsule, cerebral peduncle and optic radiation in the adult onset ALD including AMN and symptomatic heterozygote, have not been reported and this confinement may indicate an early stage of the disease.

Computed Tomographic Features of Uterine Myoma

Eighty-three cases of uterine inyoina studied by computed tomography (LT) and subsequently operated on are reviewed, and the CT features of uterine myoma are presented. Postoperative diagnoses were uterine myoma in 63 (76%), uterine adenomyosis in 15 (18%), ovarian tumor in 4 (5%), and abscess in Douglass pouch in 1 (1 %).

Breast masses: Color Doppler, power Doppler, and spectral analysis findings

To determine the diagnostic efficacy of power Doppler sonography (PDS) with spectral analysis for breast diseases, we retrospectively compared PDS and color Doppler sonography (CDS) in patients with breast lesions.

Clinical application of computed tomography to thyroid disease.

CT examinations were carried out in 62 patients with various thyroid disorders, 42 patients with thyroid nodules, 12 with diffuse abnormality and 8 of others. Evaluation was made whether CT could provide more information compared with other techniques. Cystic thyroid nodules could be differentiated from solid nodules with a reasonably high degree of accuracy. Uncalcified thyroid carcinoma was noticed as an ill-defined nodule with irregular wall, grossly the same in density with the muscle in plain CT, and not opacified by contrast material. CT has the ability to define the nature of the thyroid nodules better than other nontraumatic diagnostic modalities.

Infrahyoid spread of deep neck abscess: anatomical consideration.

Abstract. The aim of this study was to determine the pathway of infrahyoid extension of the oropharyngeal abscess considering the anatomy of the fascial spaces by cross-sectional imaging. CT scans and MR images were retrospectively reviewed in ten patients with known infrahyoid extension of oropharyngeal abscesses (eight with acute tonsillitis, two with acute phlegmonous oropharyngitis). In seven of eight patients tonsillar abscesses descended along the deep cervical fascia converging on the hyoid bone and further accumulated in the anterior cervical space through which extension to the mediastinum took place in four patients. In seven patients the abscesses involved the retropharyngeal space at the infrahyoid neck. In two of these seven patients the abscesses directly extended down into the upper mediastinum through the retropharyngeal space. In one patients of the seven mediastinal spread of an abscess occurred through the posterior cervical space, not through the retropharyngeal space. Cross-sectional imaging is valuable in the evaluation of deep neck abscesses and the pathway of spread. The anterior cervical space in the infrahyoid neck is important for mediastinal extension of pharyngeal abscesses.

Staging of Renal Cell Carcinoma by Computed Tomography

To evaluate the efficacy of computed tomography (CT) in the diagnostic workup of renal cell carcinoma, CT findings were correlated with surgical and pathological findings in 40 cases. Fifteen cases without obliteration of perinephric fat or thickening of Gerotas fascia were confined within the renal capsule. Eighteen lesions showing anatomic contact with adjacent organs were either within the renal capsule or Gerotas fascia but never beyond Gerotas fascia. Two cases (Stage II) showed thickening of Gerotas fascia and two cases (Stage IV) showed tumor infiltration into the spleen. Computed tomography was found to be a useful method for the investigation of tumor thrombosis and lymph node metastasis.

New method for evaluation of perigastric invasion of gastric cancer by right lateral position CT

The purpose of this study was to evaluate usefulness of right lateral position CT in determining invasion of gastric cancer into adjacent organs. We assessed whether position shift, a change in the relative location of a gastric tumor and adjacent organs between the supine position and right lateral position CT, was a useful sign for absence of invasion into perigastric organs. In 37 patients with advanced gastric cancer with doubtful invasion into adjacent organs by conventional CT after 500 ml water oral intake, additive right lateral CT was performed. Of 24 cases of lesions in the gastric body, 16 had a position shift and no invasion into adjacent organs at surgery (T3), and 8 had no position shift and invasion (T4). The accuracy was 100%. Six gastric cardial and 7 pyloric tumors showed no position shift, and 3 cardial and 2 pyloric tumors were proved to be noninvasive (T3). The accuracy of cardial and pyloric tumor was 50 and 71%. We concluded that position shift may be useful in the diagnosis of invasion of adjacent organs by gastric cancer, limited to in cases with gastric body cancer.

Improved Mechanical Thrombolysis with the Addition of Recombinant Tissue-Type Plasminogen Activator: In Vitro Study with Use of Cr-51–labeled Clots

PURPOSE To explore the potential effect of infusion of recombinant tissue-type plasminogen activator (rt-PA) during mechanical thrombolysis. MATERIALS AND METHODS Clots containing chromium-51-labeled platelets produced from blood from two donors were placed in a solution of rt-PA (1.25 micrograms/mL) or in saline solution and were pulverized with a mechanical thrombolysis catheter. The resultant slurry was passed through a filter with a pore size of 10 microns, and the radioactivity of the clot residue on the filter was measured. For each donor, the percentage of clot remaining was calculated from the residual radioactivity. RESULTS The mean percentages of clot remaining were 72.0% for clots in saline (n = 10) and 44.4% for clots in rt-PA (n = 10) in donor 1 and 58.9% (n = 14) and 36.4% (n = 14), respectively, for donor 2. In both cases, the mean percentage of clot remaining was significantly lower when mechanical thrombolysis was performed in the presence of rt-PA. CONCLUSION These results indicate the feasibility of combined pharmacologic and mechanical thrombolysis.