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Biomedical subjects

N Yama

Publications and source records attributed to N Yama.

14 recordsLinked to original sources

Nominal free air in the left inguinal fossa due to perforation of the sigmoid colon in a case of blunt abdominal trauma: CT diagnosis.

We present a case of perforation of the sigmoid colon due to blunt abdominal trauma. Computed tomography showed nominal free air in the inguinal fossa. The distribution of free air may be a clue to the site of an injured intestine. Early detection of intestinal injury is difficult, but repeated computed tomography after several hours may reveal increased free air.

Abdominal Injuries↗

Emergency endovascular stent-grafting for infected pseudoaneurysm of brachial artery.

The use of covered stents in an infected field is controversial. It is generally recommended that infected aneurysms be treated using autografts or allografts. We report a case of infected brachial pseudoaneurysms that developed after medical debridement of a methicillin-resistant Staphylococcus aureus (MRSA)-infected wound of the right arm and emergency brachial artery bypass-grafting using the saphenous vein, which was successfully treated by endovascular stent-grafting followed by antibiotic administration. The present case suggests that endovascular stent-grafting prevents rupture and occlusion of infected aneurysms and enables the continued administration of antibiotics.

Adult↗

Pancreas: imaging diagnosis with color/power Doppler ultrasonography, endoscopic ultrasonography, and intraductal ultrasonography.

Recent advances of ultrasound imaging have made possible to depict various diseases and conditions of the pancreas. Color/power Doppler ultrasonography, endoscopic ultrasonography, and intraductal ultrasonography are feasible to show vascular abnormalities, differentiate the solid and cystic tumors, decide tumor extent, and help to perform interventional treatments of the pancreatic diseases. Those techniques will contribute to the more precise and easier diagnosis and to prompt decision of the treatments of the pancreatic disorders. Radiologists should recognize the diagnostic feasibility and limitations of those techniques in order to avoid unnecessary examinations on the patients, and obtain precise diagnostic images.

Endoscopy, Gastrointestinal↗

Virtual CT cholangioscopy: comparison with fiberoptic cholangioscopy.

BACKGROUND AND STUDY AIMS: No studies comparing virtual computed tomography (CT) cholangioscopy of the common bile duct compared with fiberoptic cholangioscopy are available. The aim of our study was to evaluate the feasibility of virtual CT cholangioscopy of the common bile duct. PATIENTS AND METHODS: The study population comprised 52 patients (25 women, 27 men; mean age 56.5, range 32 - 81) with biliopancreatic disorders. Endoscopic images were produced by a volume-rendering method and a perspective projection. The ability to detect the endoluminal view and abnormalities of the common bile duct by virtual CT cholangioscopy and fiberoptic cholangioscopy was evaluated. RESULTS: Except for two cases (4 %), virtual CT cholangioscopy revealed excellent and moderate endoluminal visualization. There was no significant difference between the techniques (virtual CT cholangioscopy vs. fiberoptic cholangioscopy: excellent, 73 % vs. 85 %, P = 0.149; moderate 23 % vs. 15 % (P = 0.319); poor, 4 % vs. 0 %, P = 0.153). Virtual CT cholangioscopy revealed no significantly different ability to detect stenosis and obstruction of the common bile duct, compared with fiberoptic cholangioscopy. However, the ability of virtual CT cholangioscopy to detect minute papillary tumors (virtual CT cholangioscopy 30 % vs. fiberoptic cholangioscopy 100 %, P = 0.001) and stones smaller than 5 mm (virtual CT cholangioscopy 25 % vs. fiberoptic cholangioscopy 100 %; P = 0.002 was significantly less than that of fiberoptic cholangioscopy. CONCLUSIONS: Virtual CT cholangioscopy cannot replace fiberoptic cholangioscopy completely. However, the use of this technique, instead of fiberoptic cholangioscopy, may be feasible for following up patients after biliary intervention.

Adult↗

Usefulness of magnetic resonance imaging for surgical management of extravasation of an antitumor agent: a case report.

We report a case of extravasation of an antitumor agent by preoperative magnetic resonance (MR) imaging. MR studies demonstrated a decreased signal intensity on T1- and T2-weighted images and a strong enhancement of contrast media in injured tissue, including subcutaneous adipose tissue and deep fascia, which was cicatrical macroscopically. The MR findings were in good agreement with the macroscopic findings. We believe that MR imaging is useful for estimating deep tissue damage due to extravasation of an antitumor agent.

Adipose Tissue↗

Spiral CT venography of the lower extremities by injection via an arm vein in patients with leg swelling.

The purpose of this prospective study was to assess the role of spiral CT venography (CTV) via an arm vein injection in the detection of causes of leg swelling. 42 consecutive patients with leg swelling were studied with indirect spiral CTV and ultrasound (US). CT parameters were as follows: 5 mm beam collimation; 7-10 mm s(-1) table speed; and 2-3 mm reconstruction. Two consecutive spiral scans with a 40 s exposure time were performed from the pelvis to the knee. One bolus of 150 ml non-ionic contrast medium was injected at a rate of 3 ml s(-1) by a power injector via an arm vein. The delay times to the first and second scans were 120 s and 180 s, respectively. Spiral CTV demonstrated not only deep vein thrombosis (DVT) (n=12) but also other abnormalities (n=25). US showed DVT (n=10) and some other abnormalities (n=5). The sensitivity and specificity of spiral CTV for femoropopliteal DVT, as compared with US, were both 100%. Two cases of DVT in the left common-external iliac vein (iliac vein compression syndrome) detected by spiral CTV were not confirmed by US. We were able to evaluate DVT above the knee with this method. Indirect spiral CTV showed promise for the diagnosis of DVT and other soft tissue diseases in patients with leg swelling.

Adult↗

Acquired anomalous intrapulmonary venous connection secondary to pulmonary venous stenosis.

An unusual case of acquired development of anomalous intrapulmonary venous connection with pulmonary venous stenosis is presented. Appearances on a chest radiograph resembled the "scimitar" sign in a patient with previous surgery for partial anomalous pulmonary venous return. Spiral CT and pulmonary arteriography showed stenosis of the right upper pulmonary vein and an anomalous intrapulmonary venous connection between the right upper pulmonary vein and the right lower pulmonary vein. We consider the slow progression of pulmonary vein stenosis led to anomalous intrapulmonary venous connection as an intrapulmonary collateral.

Adult↗

[Estimation of 99mTc-GSA receptor amount by non-linear 3-compartment model: ligand-receptor binding model without blood sampling].

99mTc-GSA (galactosyl serum albumin) receptor amount (Ro) was estimated by a non-linear 3-compartment model of the ligand-receptor binding without blood sampling. Forward/reverse rate constants and receptor amount were assumed to be variable. Relationship between this parameter and other conventional parameters including ICG R15 (15-minutes retention rate of indocyanine green) was evaluated for 43 surgical candidates with liver tumors. Linear relationships between Ro and HH15 and LHL15 were R2 = 0.73 and 0.72, respectively. Linear relationship between Ro and Rmax, the maximum removal rate, is also good (R2 = 0.84), and the regression line (y = 0.038x + 0.066) was slightly over 0 at y-interception. Linear relationship between Ro and ICG R15, was poor (R2 = 0.39) and relationship was rather a concave shape. Linear relationship of reduction rate between Ro and non-tumor tissue volume of the liver, which assessed at the same day of two weeks after the operation, was y = 1.09x - 0.01 (R2 = 0.82). GSA receptor amount, Ro, seems to change proportional to non-tumor liver tissue volume changing before and after hepatectomy. Complementary to ICG R15, it may be an useful and intuitive parameter for hepatectomy.

Asialoglycoprotein Receptor↗

Mucin-producing pancreatic tumors: comparison of MR cholangiopancreatography with endoscopic retrograde cholangiopancreatography.

PURPOSE: To compare magnetic resonance cholangiopancreatography (MRCP) with endoscopic retrograde cholangiopancreatography (ERCP) in the detection of mucin-producing pancreatic tumors. MATERIALS AND METHODS: The authors retrospectively reviewed MRCP and ERCP images obtained in 28 patients with mucin-producing pancreatic tumors. Detectability of the pancreatic duct and its branches, intraductal cystic lesions, and intracystic nodules or septa was assessed. RESULTS: MRCP depicted cystic dilated ductal branches significantly better than did ERCP (P < .001). The difference in the number of nodules or septa detected with MRCP compared with ERCP was not significant. MRCP, however, simultaneously showed not only the main pancreatic duct but also the cystic lesions; this was not always possible with ERCP. CONCLUSION: MRCP appears to be more effective and less invasive than ERCP to evaluate changes in the size and extent of tumors and to determine if new lesions appear, as well as to follow up mucin-producing pancreatic tumors.

Adenocarcinoma, Papillary↗

Long survival of patients with unresectable cervical carcinoma after radiotherapy.

We report our experience with radiotherapy for three patients with cervical carcinoma in whom surgery had been downgraded to the performance of exploratory laparotomy only, because of extensive primary tumor or nodal invasion to the surrounding organs and vessels. Tumor invasion to the bladder, side wall invasion or unresectable nodal disease at the time of exploration prevented definitive surgery in our case series. After laparotomy, we carried out radiation therapy consisting of external irradiation to the pelvis and intracavitary irradiation with high dose rate 60Co or low dose rate 137Cs sources. Local and regional control was obtained in all three patients, and there was no locoregional recurrence during > 5 years of follow-up. One patient died of paraaortic lymph node metastases, but she had no pelvic recurrence. Several authors have reported an increased risk of small bowel obstruction in patients who undergo laparotomy before radiotherapy. None of our patients developed small bowel obstruction, although one had anal bleeding which was cured by conservative therapy. Radiotherapy was effective for locoregional control in all three patients with unresectable cervical carcinoma.

Aged↗

Spontaneously reduced midgut malrotation: CT diagnosis.

Midgut malrotation is a relatively rare congenital malformation that arises from an error of rotation and fixation of the midgut. We report a case of spontaneously reduced duodenal malrotation diagnosed by computed tomography and roentgenography after the ingestion of barium.

Adult↗

Pseudoaneurysm of the superficial femoral artery in Behçet's disease with spontaneous thrombosis followed by CT angiography.

A 25-year-old man developed sudden pain and a pulsating mass in the left thigh. A diagnosis of Behçet's disease was made because of four major symptoms. Laboratory data indicated active inflammation. Emergency spiral computed tomographic angiography (CTA) showed an aneurysm of the left superficial femoral artery (SFA). Under steroid therapy, follow-up spiral CTA showed spontaneous occlusion of the aneurysm. In the active phase of arteritis, spiral CTA is useful for the diagnosis of arterial lesions to avoid the arterial puncture of conventional arteriography.

Adult↗

Anomalous vessels in the middle ear associated with congenital anomalies of the internal carotid artery.

A case with unilateral hypoplasia of the internal carotid artery was reported. The rerouting of anomalous vessels in the middle ear, visualized by otoscopy, was demonstrated with CT and MRI. Associations with internal carotid hypoplasia, the intercarotid collaterals, both anomalous middle ear arteries and the enlarged internal maxillary artery were confirmed with MRI. MR images were helpful to diagnose not only the anomalous vessels but also the multiple anastomoses.

Carotid Artery, Internal↗