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M Dohke

Publications and source records attributed to M Dohke.

At least 19 recordsLinked to original sources
PubMed2001

Comparison of Bassini repair and mesh-plug repair for primary inguinal hernia: a retrospective study.

The purpose of this study was to compare the mesh-plug repair with the Bassini repair for the treatment of primary unilateral inguinal hernias. Patients with primary unilateral inguinal hernias who underwent a Bassini repair (n = 118) between January 1992 and May 1996 and a mesh-plug repair (n = 113) between July 1996 and April 1998 were retrospectively reviewed. We recorded information regarding the types of hernia according to Nyhus classification, operation time, complications, postoperative recovery, and recurrence after surgery. The two groups were comparable regarding age, sex, side of hernia, types of hernia, and the follow-up interval. The operation time was 55 +/- 20min for Bassini repair and 54 +/- 18min for mesh-plug repair. There was no incidence of mesh infection in the mesh-plug repair cases. The amount of diclofenac sodium (suppository) was 307 +/- 222mg in the Bassini repair group and 132 +/- 182mg in the mesh-plug repair group (P < 0.0001). The length of hospital stay was 8.2 +/- 2.0 days in the Bassini repair group and 4.3 +/- 2.7 days in the mesh-plug repair group (P < 0.01). Nine patients (7.6%) in the Bassini repair group had recurrence, compared with one patient (0.9%) in the mesh-plug repair group. The recurrence-free survival in the mesh-plug repair group was significantly longer than that in the Bassini repair group (P = 0.03). In conclusion, patients with primary unilateral inguinal hernias who undergo a mesh-plug repair recover more rapidly and have less recurrence in comparison with those who undergo a Bassini repair.

Aged↗
PubMed2001

Fast magnetic resonance imaging of pelvic organ prolapse.

Pelvic organ prolapse is abnormal displacement of the pelvic organs from their normal anatomical position. Patients may present with a variety of symptoms, including pain, incontinence, constipation, urinary retention, and defecatory dysfunction. Any combination of cystocele, rectocele, enterocele, sigmoidocele, peritoneocele, and prolapse of the vagina and uterus may occur. Therefore, accurate preoperative evaluation of each organ is important for proper surgical planning. Compared with physical examination and other imaging modalities, advantages of magnetic resonance imaging (MRI) include a global multiplanar view of the pelvis, and the lack of ionizing radiation and invasive procedures. Subsecond MRI techniques have not only shortened the imaging time to minimize motion artifacts but provide the capability for dynamic MRI. In this pictorial essay, we describe fast MRI techniques, MRI findings, and the associated clinical findings in patients with pelvic organ prolapse. We also refer to limitations of MRI.

Female↗
PubMed2000

Pseudo-obstruction of the extrahepatic bile duct due to artifact from arterial pulsatile compression: a diagnostic pitfall of MR cholangiopancreatography.

PURPOSE: To evaluate the frequency of artifact from arterial pulsatile compression as the cause of pseudo-obstruction of the extrahepatic bile duct at magnetic resonance (MR) cholangiopancreatography (MRCP) and specify the causative vessels. MATERIALS AND METHODS: In 234 patients (102 men, 132 women; age range, 25-80 years), MRCP images obtained by using a single-shot turbo spin-echo sequence were reviewed to assess pseudo-obstruction of the extrahepatic bile duct caused by vascular compression. Dual-phase spiral computed tomography, contrast material-enhanced three-dimensional MR angiography, and/or digital subtraction angiography also were performed to determine the vessel that caused the pseudo-obstruction. RESULTS: Thirty-six pseudo-obstructions due to vascular compression were found in 33 (14%) patients. The common hepatic duct (27 [75%] sites) was the most common pseudo-obstruction site, followed by the left hepatic duct (four [11%] sites), proximal common bile duct (three [8%] sites), and right hepatic duct (two [6%] sites). The causative vessels were identified as the right hepatic artery at 24 (67%) sites; gastroduodenal artery, two (6%) sites; cystic artery, two (6%) sites; proper hepatic artery, one (3%) site; and an unspecified branch of the common hepatic artery, seven (19%) sites. CONCLUSION: At MRCP, pseudo-obstruction of the extrahepatic bile duct can be caused by pulsatile vascular compression of the hepatic and gastroduodenal arteries, and it should not be misdiagnosed as a bile duct tumor or biliary stone.

Adult↗
PubMed2000

Scrotal disorders: evaluation of testicular enhancement patterns at dynamic contrast-enhanced subtraction MR imaging.

PURPOSE: To evaluate testicular enhancement patterns in various scrotal disorders at dynamic contrast medium-enhanced subtraction magnetic resonance (MR) imaging. MATERIALS AND METHODS: Forty-two patients with scrotal symptoms (22 testicular diseases, 20 extratesticular scrotal disorders) underwent three-dimensional (3D) fast field-echo or fast spin-echo dynamic subtraction MR imaging after injection of paramagnetic contrast medium. The relative percentages of peak height and mean slope of the testes on the affected side were compared with those on the unaffected side by using time-signal intensity curves. RESULTS: Extratesticular scrotal disorders (time-signal intensity curve mean peak height, 93.1%; mean slope, 89.8%) showed gradual and progressive increase in homogeneous testicular contrast enhancement in all normal testes. Relative percentages of peak height and mean slope of testicular torsion (mean peak height, 17.3%; mean slope, 10.6%), infarction (mean peak height, 30.4%; mean slope, 19.8%), traumatic hemorrhagic necrosis (mean peak height, -3.5%; mean slope, -12.0%), and epidermoid cyst (mean peak height, -6.6%; mean slope, -14.2%) were significantly lower than those of extratesticular scrotal disorders. Acute mumps orchitis (mean peak height, 135.1%; mean slope, 307.5%) and malignant testicular tumor (mean peak height, 178.7%; mean slope, 467.6%) showed higher relative percentages of peak height and mean slope. CONCLUSION: Dynamic contrast-enhanced subtraction MR imaging can provide information about testicular perfusion on the basis of contrast enhancement and can be used to differentiate testicular diseases from scrotal disorders.

Adolescent↗
PubMed1998

High-resolution MR cholangiopancreatography.

1. High-resolution MRCP is a noninvasive imaging modality for depicting the pancreatobiliary tree. The imaging quality of high-resolution MRCP is satisfactory. MRCP can demonstrate dilation, stenosis, and intraductal filling defects of both the biliary tract and the pancreatic duct, which meets the clinical demand for pancreatobiliary imaging. 2. MRCP was successful in almost all the patients. However, the causes of MRCP failure were patient motion, irregular respiratory rhythm, severe pneumobilia, and massive ascitic fluid. 3. When only MIP reconstructed images were used for interpretation, small intraductal filling defects such as a gallstone can be missed. In combination with coronal source images, the ability to detect intraductal stones can be increased. 4. Ferrite ammonium citrate (FAC) is useful in suppressing the background signal intensity of gastrointestinal contents so that the ducts can be clearly visualized. The other technique for decreasing the background signal intensity is target MIP postprocessing, which works well for better visualization of the ducts. 5. The degree of ductal narrowing tends to be overestimated with MRCP because of MIP reconstruction artifact and lower spatial resolution of MRCP than ERCP. 6. MRCP has a diagnostic pitfall of a pseudostenosis of extrahepatic ducts, which may lead to a false-positive diagnosis of ductal narrowing. This pitfall may be caused not only by MIP postprocessing artifacts but by gas, surgical metal, and vascular compression of right hepatic artery. There is another diagnostic pitfall that it is difficult to differentiate intraductal mucin from pancreatic fluid in dilate pancreatic ducts, although ERCP identifies mucin as intraductal filling defects.

Biliary Tract↗
PubMed1998

[Clinical usefulness of fat suppression technique for MR cholangiopancreatography (MRCP)].

In order to obtain high quality of MRCP image, it is important to reduce the background signal intensity and increase the contrast of the pancreatobiliary ducts relative to surrounding fat tissue. The combination of long effective-TE and fat suppression technique including the short-TI inversion recovery and chemical-selective fat suppression enables to suppress the background signal intensity enough to obtain high quality MR cholangiopancreatogram. However, susceptibility artifacts from the metal, gastroduodenal gas, and vascular pulsation can be augmented by using the chemical-selective fat suppression technique, which may result in signal loss of the pancreatobiliary ducts. This potential diagnostic pitfalls can be avoided by interpreting the coronal source images obtained with long effective-TE and without fat suppression technique.

Adipose Tissue↗
PubMed1997

Perineural invasion by ductal adenocarcinoma of the pancreas.

BACKGROUND AND OBJECTIVES: The correlation between various levels of perineural invasion by pancreatic carcinoma and the patient's prognosis has never been cleared. The authors carried out a histopathologic study of resected pancreatic carcinoma to elucidate the significance of a new histologic finding concerning perineural invasion, which we designated "intrapancreatic, extratumoral perineural invasion (nex)," and also to determine its predictive value for prognoses of patients after surgical removal of the tumor. METHODS: We investigated 90 patients with pancreatic adenocarcinoma who had undergone pancreatic resection. The prognoses of all patients were explored, and correlations between survival and pathologic factors were statistically examined for neural invasion. RESULTS: Nex was found in more than 50% of resected pancreases. A statistically significant association was found between the presence of nex and the grade of intrapancreatic neural invasion or the presence of extra-pancreatic neural plexus invasion. Nex was also found to be associated with patient survival after removal of the tumor. CONCLUSIONS: Nex appears to be an element predicting pancreatic cancer infiltration to the extrapancreatic nerve plexus and also to be a factor influencing postoperative survival of patients with pancreatic carcinoma.

Adult↗
PubMed1997

[MR dynamic subtraction angiography (MRDSA)].

We have developed magnetic resonance dynamic subtraction angiography (MRDSA), which depicts the long segments of arteries from the upper abdomen to the lower leg by using a small dose of Gd-DTPA. The lower half of the body was divided into three imaging regions, abdomen, thigh and lower leg, in the order of scanning. The contrast-enhanced three-dimensional breath-hold fast field echo technique with half Fourier acquisition was performed in 3 normal volunteers and 12 patients with vascular diseases (4: abdominal aortic aneurysm, 8: atherosclerotic occlusive disease). The images were reconstructed into composite images by using maximum-intensity-projection postprocessing after the subtraction of precontrast images. A bolus intravenous injection of a small dose of Gd-DTPA (0.02-0.05 mmol/kg) was given, followed by the five sets of scans. The acquisition time of each set was 8 to 16 seconds, and the total dose used in MRDSA was 0.1 to 0.15 mmol/kg. The image quality of MRDSA was satisfactory in 3 normal volunteers and 12 patients with vascular diseases. MRDSA demonstrated aortic aneurysm and atherosclerotic obstruction as clearly as conventional angiography. MRDSA can replace conventional angiography.

Angiography, Digital Subtraction↗
PubMed1995

[Thoracoscopic surgery, current indication and technique].

Thoracoscopy has become an important tool in the diagnosis and management of intrathoracic disease. The development of endoscopic suturing techniques and stapling devices for abdominal surgery dramatically expanded the potential of thoracoscopic surgery. Between 1993 and 1994, 43 patients underwent thoracoscopic surgery. Lung resection were performed on 23 patients for pulmonary nodules and on 9 patients for diagnosis of interstitial lung disease. Extirpation were performed on 2 patients for mediastinal tumor. A procedure done thoracoscopically is far less invasive and the postoperative pain and its consequences are drastically reduced. As endoscopic instrumentation develops, newer operations will become technically feasible. We think that indications for thoracoscopic surgery will expand in developing these techniques in the future, if thoracoscopic surgery is safer and more efficient.

Adult↗
PubMed1992

Percutaneous transhepatic biliary drainage in patients with malignant biliary obstruction of the hepatic confluence.

Despite many studies on percutaneous transhepatic biliary drainage (PTBD), there are no satisfactory reports of PTBD for malignant obstruction of the hepatic confluence. In this study, the results of PTBD using the direct anterior approach under fluoroscopic guidance are described in 16 patients with malignant biliary obstruction of the hepatic confluence. A total of forty-two drainage catheters were placed in the 16 patients: one catheter was placed in three patients; two catheters in six; three catheters in four; four catheters in two; seven catheters in one. PTBD was successful in 100% of the cases with no mortality or critical complications, and the biliary decompression effect of PTBD was highly satisfactory. Nine patients underwent histologically curative hepatectomies. Two of the nine resected cases died of postoperative hepatic failure, but the postoperative course in the others was satisfactory. The authors stress that selective biliary drainage for each isolated segmental duct is mandatory for advanced malignant obstruction of the hepatic confluence.

Adult↗
PubMedDate not supplied

Struma ovarii: MR findings.

PURPOSE: The purpose of this study was to determine the MR appearance of struma ovarii correlating with the pathological features. METHOD: MR findings of two patients with struma ovarii were retrospectively reviewed and compared with the pathological findings. RESULTS: Both tumors were complex masses composed of multiple cysts and solid components. The size and signal intensity of multiple cysts varied within the tumor. Hyperintense cystic areas on T1-weighted images were thought to correspond pathologically to hemorrhagic cysts and follicles containing viscous proteinaceous colloid. Solid components had as high a signal intensity as did uterine endometrium on T2-weighted images and as intermediate a signal intensity as did uterine muscle layer on T1-weighted images. After intravenous administration of gadolinium-DTPA, the solid components showed marked contrast enhancement. There was also ascitic fluid associated with adhesion and peritoneal thickening. CONCLUSION: The characteristic MR appearance of struma ovarii is thought to be a mixed mass composed of T2-hyperintense solid components with intense contrast enhancement and multiple T1-hyperintense cystic areas suggestive of hemorrhagic degeneration and viscous proteinaceous colloid.

Adult↗