Yasunao Ishiguro

Colocutaneous fistula after left inguinal hernia repair using the mesh plug technique.

A 34-YEAR-OLD MAN was admitted with purulent discharge from a left inguinal hernia scar. Three years before, a hernioplasty using the mesh plug technique was performed at another hospital, with an uneventful postoperative course. Two years later, he noted purulent discharge from the operative site that was treated unsuccessfully with oral antibiotics, and he was referred to our hospital. On admission, his temperature was 36.2 C. He had a yellow-green foul-smelling discharge at the lateral edge of the operative scar. Induration was palpable under the scar, and the surrounding skin was erythematous (Fig 1). Laboratory findings were normal (WBC 9000/mm). Fistulography (Fig 2) demonstrated contrast flowing past the mesh plug and into the sigmoid colon; a colocutaneous fistula caused by migration of the mesh plug was diagnosed. After partial resection of the

Experimental system for in-situ measurement of temperature rise in animal tissue under exposure to acoustic radiation force impulse

PurposeAcoustic radiation force impulse (ARFI) has recently been used for tissue elasticity measurement and imaging. On the other hand, it is predicted that a rise in temperature occurs. In-situ measurement of temperature rise in animal experiments is important, yet measurement using thermocouples has some problems such as position mismatch of the temperature measuring junction of the thermocouple and the focal point of ultrasound. Therefore, an in-situ measurement system for solving the above problems was developed in this study.MethodsThe developed system is composed mainly of an ultrasound irradiation unit including a custom-made focused transducer with a through hole for inserting a thin-wire thermocouple, and a temperature measurement unit including the thermocouple.ResultsThe feasibility of the developed system was evaluated by means of experiments using a tissue-mimicking material (TMM), a TMM containing a bone model or a chicken bone, and an extracted porcine liver. The similarity between the experimental results and the results of simulation using a finite element method (FEM) implied the reasonableness of in-situ temperature rise measured by the developed system.ConclusionThe developed system will become a useful tool for measuring in-situ temperature rise in animal experiments and obtaining findings with respect to the relationship between ultrasound irradiation conditions and in-situ temperature rise.

Recurrent Cholangitis by Biliary Stasis Due to Non-Obstructive Afferent Loop Syndrome After Pylorus-Preserving Pancreatoduodenectomy: Report of a Case

We report a 71-year-old man who had undergone pylorus-preserving pancreatoduodenectomy (PPPD) using PPPD-IV reconstruction for cholangiocarcinoma. For 6 years thereafter, he had suffered recurrent cholangitis, and also a right liver abscess (S5/8), which required percutaneous drainage at 9 years after PPPD. At 16 years after PPPD, he had been admitted to the other hospital because of acute purulent cholangitis. Although medical treatment resolved the cholangitis, the patient was referred to our hospital because of dilatation of the intrahepatic biliary duct (B2). Peroral double-balloon enteroscopy revealed that the diameter of the hepaticojejunostomy anastomosis was 12 mm, and cholangiography detected intrahepatic stones. Lithotripsy was performed using a basket catheter. At 1 year after lithotripsy procedure, the patient is doing well. Hepatobiliary scintigraphy at 60 minutes after intravenous injection demonstrated that deposit of the tracer still remained in the upper afferent loop jejunum. Therefore, we considered that the recurrent cholangitis, liver abscess, and intrahepatic lithiasis have been caused by biliary stasis due to nonobstructive afferent loop syndrome. Biliary retention due to nonobstructive afferent loop syndrome may cause recurrent cholangitis or liver abscess after hepaticojejunostomy, and double-balloon enteroscopy and hepatobiliary scintigraphy are useful for the diagnosis of nonobstructive afferent loop syndrome.

Development of in vivo measurement system for temperature rise in animal tissue under exposure to ultrasound with acoustic radiation force

Acoustic radiation force (ARF) has been recently used for the tissue elasticity measurement and imaging. On the other hand, it is predicted that the higher temperature rises occur. In vivo measurement of temperature rise in animal experiments is important, whereas the measurement using thermocouples have some problems such as position mismatch of a temperature measuring junction of thermocouple and a focal point of ultrasound and so on. Therefore, in vivo measurement system for solving the above problems was developed in this study. The feasibility of the developed system was verified by the experiments using a tissue mimicking materials (TMM), TMM with a bone mode, an extracted porcine liver and a bone of chicken. Moreover, relations between conditions of ultrasound irradiation and temperature rises were investigated using the system. These results showed that temperature rises at focus on the surface of bone may exceed an allowable temperature rise which WFUMB guideline recommends, even though the acoustic intensity is within the limits of acoustic output regulation in diagnostic ultrasound devices.

Early-Phase Thin-Slice CT in the Diagnosis of Small Insulinomas

CONTEXT Insulinomas, which are generally smaller than 2 cm, may be difficult to detect by routine imaging modalities including abdominal ultrasonography, computed tomography, and magnetic resonance imaging. Although preoperative detection of insulinomas is essential for operative planning, it is often challenging due to their small size. While arterial stimulation and venous sampling has been used in patients with insulinomas it has been largely supplanted by early-phase thin-slice computed tomography. CASE REPORT We report three patients with insulinomas, which were not detected by routine computed tomography scan, but were successfully imaged using early-phase thin-slice computed tomography. Enucleation was performed in all patients based on preoperative imaging. All three patients had an unremarkable postoperative course. CONCLUSION Early-phase thin-slice computed tomography is recommended for the preoperative identification of insulinomas. This non-invasive imaging technique should be considered before performing arterial stimulation and venous sampling.

In vivo measurement of temperature rise in living rabbit's liver exposed to ultrasound with acoustic radiation force

Acoustic radiation force (ARF) has been used for evaluating tissue elasticity, and is generated by longer pulse duration (PD) and higher acoustic pressure than those used in the conventional ultrasound devices. Although the use of ARF produces relatively-high temperature rise in living biological tissue, the thermal effect of ARF is uncertain. In addition, considering application to the diagnosis of liver, the thermal effect in combination use of ARF and contrast agents should also be considered. In order to evaluate these effects, we have developed a temperature measurement system using a thermocouple for experiment on living animal. In this study, the temperature rise in living rabbits liver exposed to ultrasound with ARF was measured and evaluated by using the developed system. As the results, all of maximum temperature rise within regulation limits was below 1.5 °C. In addition, there was no significant difference between temperature rises in the liver with and without contrast agents.

Gastric gastrointestinal stromal tumor with synchronous metastasis to the esophagus: case report and review of the literature

We report a patient with synchronous gastrointestinal stromal tumors (GISTs) of the stomach and esophagus. The gastric GIST was larger than that in the esophagus, and no direct connection between the two lesions was seen microscopically. Based on molecular analysis, both lesions had the same c-kit mutation on exon 11, with deletion of codon 557–558. Analysis of normal gastric tissue showed no mutations. The gastric GIST was the primary lesion, and the esophageal tumor was thought to suggest a hematogenous metastasis. A liver metastasis in S6 appeared 6 months after surgery. Imatinib mesylate has been an effective treatment for liver metastasis at follow-up of 2 years.