Takuji Mogami

Percutaneous MR-guided cryoablation for malignancies, with a focus on renal cell carcinoma

Cryosurgery is the oldest thermal ablation method, and was first performed in the mid-nineteenth century. Since the development of cryosurgical systems capable of delivering liquid nitrogen, organs in various regions have been treated with cryosurgery. However, the lack of an adequate monitoring modality during the freezing process did not allow the precise and complete destruction of lesions deep inside the parenchyma. This led to local recurrences caused by unsatisfactory results of treatment. Recently, a magnetic resonance (MR)-compatible argon-based cryoablation sytem has been developed, and a combination of this cryoablation system and MR imaging has been shown to be an effective method for treating malignant tumors. In this article, we describe our clinical experience of percutaneous MR-guided cryoablation for malignancies, focusing on renal cell carcinoma.

Digestive Tract Complications of Renal Cryoablation

We report a case each of duodenorenal and colorenal fistula that arose after computed tomography-guided percutaneous cryoablation (PCA) for renal cell carcinoma and use imaging and endoscopic findings to analyze their causes and mechanisms. Both complications occurred though the edge of the iceball did not touch the intestinal wall, and patients’ symptoms and fistula formation occurred several days after the PCA procedure. Based on imaging and endoscopy findings, we suspected the colorenal fistula resulted from bowel injury caused by ischemia from the occlusion of small vessels at the procedure’s low temperature. Both cases were resolved conservatively without surgical intervention.

Evaluation of the Ossification of the Cervical Posterior Longitudinal Ligament Utilizing X-Ray, CT and MR Imaging

Citation Kobashi Y, Munetomo Y, Baba A, Yamazoe S, Mogami T. Evaluation of the ossification of the cervical posterior longitudinal ligament utilizing Xray, CT and MR imaging. Orthop Res Traumatol Open J. 2017; 2(1): 35-39. doi: 10.17140/ORTOJ-2-109 Volume 2 : Issue 1 Article Ref. #: 1000ORTOJ2109 Evaluation of the Ossification of the Cervical Posterior Longitudinal Ligament Utilizing X-Ray, CT and MR Imaging

Ankle and Foot Injuries: MRI Pitfalls

Magnetic resonance imaging (MRI) is an excellent modality for assessment of sports and overuse injuries of the ankle and foot. However, the anatomy of this region is complex, with several bones, ligaments, and tendons being subject to possible trauma. A good working knowledge of the appearances of normal anatomy, anatomical variants, and pathology is needed to avoid misdiagnosis. This chapter aims to discuss potential pitfalls in the MRI of the ankle and foot, categorizing the injuries into five painful sites, namely, lateral, medial, dorsal, and posterior ankle and mid- and anterior foot.

Iliopsoas Tendon Injury In an Adolescent: A Case Report

1Department of Radiology, Tokyo Dental College, Ichikawa General Hospital, 5-11-13, Sugao, Ichikawa, Chiba, 271-8513, Japan 2Department of Radiology, Fujisawa Shonandai Hospital, Kanagawa Prefecture 252-0802, Fujisawa, Japan *Corresponding author Yuko Kobashi, MD Department of Radiology Tokyo Dental College Ichikawa General Hospital 5-11-13, Sugao, Ichikawa Chiba, 271-8513 Japan Tel. +81-47-322-0151 Fax: +81-47-325-4456 E-mail: ykobashi@jikei.ac.jp

Two Case Reports of Angioleiomyoma of the Finger

Angioleiomyoma represents a benign stromal tumor, which usually occurs in the subcutaneous tissue of the extremities. The angioleiomyoma in the finger is rare. We report 2 rare cases of an angioleiomyoma in finger. Case one, was a 72-year-old man with a mass on the radial side of distal phalanx of the left third finger. Case two, was a 70-year-old man with a mass on the ulnar side of interphalangeal joint of the left thumb. Both cases showed isointense to hypointense mass lesion on both T1 and T2-weighted images and were pathologically diagnosed with an angioleiomyoma. Heterogeneously isointense to hypointense on T2-weighted MR image showed two components: smooth muscle tissue punctuated with thick-walled vessles and/or hyalization on pathological finding. When much hyalization is included, it will not be enhanced on gadolinium-enhanced fat suppressed T1-weighted magnetic resonance (MR) image. Both T2-weighted and gadolinium-enhanced fat suppressed T1-weighted MR image findings should considered to predict tumor composition.

Extrapleural Solitary Fibrous Tumor of Foot: A Case Report

A 77-year-old woman was admitted to our Hospital for a mass lesion in the plantar area of the left foot. The patient referred that the mass was present for about 30 years but it had never been treated before because asymptomatic. Foot Magnetic Resonance Imaging (MRI) reviewed a low-signal-intensity tumor on both T1 weighted and T2 weighted images. Based on clinical and diagnostic imaging findings we initially suspected a fibroproliferative neoplasm like an aggressive fibromatosis. Histologically the lesion was benign fibroblastic spindle cell lesion with dense or loose collagen fibers. Cellularity was low and no mitotic figures were found. The tumor cells were positive for CD34, whereas they were negative for α smooth muscle actin, desmin, HHF35 and S100 protein. These pathological findings were consistent with an Extrapleural Solitary Fibrous Tumor (Extrapleural SFT). The Extrapleural SFT should be included in the differential diagnosis of extrapleural lesions in which MRI suggests fibrous content. These entities exhibit a dense fibrocollagenous matrix that can produce low signal intensity on T2-weighted MRI images, similar to Extrapleural SFT. However, in order to reach a proper diagnosis and treatment is essential to integrate a detailed patients’ clinical history and to perform a biopsy to collect cells for closer examination.

Acute Myocardial Infarction on Contrast-Enhanced Computed Tomography

A 79-year-old man presented to our emergency department with sudden back pain. Laboratory results showed CK 2836 U/L (normal range 30-160), CK-MB 393 U/L (<25), D-dimer 1.4 µg/mL (<1), BNP 37.9 pg/mL (<19.5), cTnl 0.133ng/mL (<0.028) and electrocardiogram showed ST elevation in V1~6. Acute myocardial infarction (AMI) was suspected. Because of the back pain, acute aortic dissection (AAD) and pulmonary thromboembolism (PE) needed to be ruled out and contrast-enhanced computed tomography (CECT) was performed. CECT images showed no findings of AAD or PE. Instead, the images revealed the decreased enhancement in the interventricular septum and apex of the left ventricle (Figure A,B, arterial phase, Figure C,D, delayed phase).