Kil Ho Cho

Subungual Tumors: Clinicopathologic Correlation with US and MR Imaging Findings

Various types of tumors can affect the subungual space, including benign solid tumors (glomus tumor, subungual exostosis, soft-tissue chondroma, keratoacanthoma, hemangioma, lobular capillary hemangioma), benign cystic lesions (epidermal and mucoid cysts), and malignant tumors (squamous cell carcinoma, malignant melanoma). Imaging plays an important role in the detection and differentiation of subungual tumors because of their small size, nonspecific clinical manifestations, and functional significance. Ultrasonography (US)-in particular, high-resolution US with color Doppler studies-provides useful information regarding tumor size, location, shape, and internal characteristics (cystic, solid, or mixed), but it is limited in the further characterization of tissue. Magnetic resonance (MR) imaging has an important role in categorizing tumors according to their anatomic location, pathologic origin, and signal characteristics. There is some overlap between the US and MR imaging features of subungual tumors; however, certain features can allow accurate diagnosis and expedite management when correlated with clinical and pathologic findings.

Fibrosarcoma in bizarre parosteal osteochondromatous proliferation.

Abstract Bizarre parosteal osteochondromatous proliferation (BPOP) is a rare benign lesion predominantly involving the small bones of the hands and feet. Malignant transformation in BPOP has not been documented in the English literature. This report presents the coexistence of fibrosarcoma with BPOP in the right distal fibula of an 18-year-old woman.

Primary clear cell sarcoma of bone

Clear cell sarcoma is a rare soft tissue sarcoma of young adults with melanocytic differentiation. It occurs predominantly in the soft tissue of extremities, typically involving tendons and aponeuroses. Primary clear cell sarcoma of bone is extremely rare. We report a case of primary clear cell sarcoma of the right first metatarsal in a 48-year-old woman and provide a literature review of the entity.

Subungual keratoacanthoma : ultrasound and magnetic resonance imaging findings

Subungual keratoacanthoma is a rare, squamoproliferative neoplasm arising at the nail bed. It may cause erosion of the underlying bone. We report a case of subungual keratoacanthoma of the right thumb in a 63-year-old man. Radiographs showed cortical erosion of the distal phalanx of the right thumb. Ultrasonography showed a mixed echoic tumor. On magnetic resonance imaging (MRI), the tumor showed intermediate signal intensity on T1-weighted images and mixed intermediate and high signal intensity on T2-weighted images with peripheral thin rim enhancement.

Postoperative ultrasonography of the musculoskeletal system

Ultrasonography of the postoperative musculoskeletal system plays an important role in the accurate diagnosis of abnormal lesions in the bone and soft tissues. Ultrasonography is a fast and reliable method with no harmful irradiation for the evaluation of postoperative musculoskeletal complications. In particular, it is not affected by the excessive metal artifacts that appear on computed tomography or magnetic resonance imaging. Another benefit of ultrasonography is its capability to dynamically assess the pathologic movement in joints, muscles, or tendons. This article discusses the frequent applications of musculoskeletal ultrasonography in various postoperative situations including those involving the soft tissues around the metal hardware, arthroplasty, postoperative tendons, recurrent soft tissue tumors, bone unions, and amputation surgery.Ultrasonography of the postoperative musculoskeletal system plays an important role in the Epub ahead of print accurate diagnosis of abnormal lesions in the bone and soft tissues. Ultrasonography is a fast and reliable method with no harmful irradiation for the evaluation of postoperative musculoskeletal complications. In particular, it is not affected by the excessive metal artifacts that appear on computed tomography or magnetic resonance imaging. Another benefit of ultrasonography is its capability to dynamically assess the pathologic movement in joints, muscles, or tendons. This article discusses the frequent applications of musculoskeletal ultrasonography in various postoperative situations including those involving the soft tissues around the metal hardware, arthroplasty, postoperative tendons, recurrent soft tissue tumors, bone unions, and amputation surgery.

Osteosarcoma of pelvic bones: imaging features

The metaphyseal locations of tubular bones with osteoid mineralization in young patients are important diagnostic radiologic features of osteosarcoma. The pelvic bones are an unusual location of osteosarcoma. Although osteosarcoma occurring in pelvic bones is not common, the osteoid matrix may be a critical finding for differentiating osteosarcoma from other common pelvic bone tumors. Therefore, the possibility of osteosarcoma in pelvic bones may be considered in the presence of osteoid matrix even in the old age group.

Ultrasonographic findings of the various diseases presenting as calf pain

There are various causes of calf pain. The differential diagnoses affecting the lower leg include cystic lesions, trauma-related lesions, infection or inflammation, vascular lesions, neoplasms, and miscellaneous entities. Ultrasound (US) provide detailed anatomical information of the calf structures, and it offers the ability to confirm, other calf abnormalities, particularly when deep vein thrombosis (DVT) is ruled out. The purpose of this article is to review the causes of a painful calf presenting as DVT and incidental findings found as part of the work-up of DVT, and to provide a broad overview of US findings and clinical features of these pathologies.

Soft Tissue Masses Showing Low Signal Intensity on T2-weighted Images: Correlation with Pathologic Findings

목적: 이전의 증례 보고에서는 저혈당성 뇌병증 환자의 뇌백질의 변화가 퇴행하기까지 수 일이 소요되었다. 본 저자들은 저혈당성 뇌병증에서 확산강조영상의 빠른 변화를 경험하였다. 이에 문헌 고찰과 함께 보고자 한다. 증례 보고: 58세 남자 환자가 반혼수 상태로 발견되었으나 혈액 검사 상 저혈당 (44 mg/dL)이 나타...

Changes of the Renal Arteries Accordding to Various Embolic Materials

The transarterial embolization has been widely used to control bleeding. It has a variety of clinical utility; to reduce bleeding on the surgical field, to reduce the size of malignant tumor as a preopearative treatment, to treat arteriovenous malformation or arterial aneurysm as a curative method and to promote life quality of patient with diffuse or multiple hepatocellular carcinoma as a palliative treatment, etc. With the advance of modem technology, various embolic materials have been also developed. However, it has not been fully investigated of histopathologic changes of the embolized organs according to the embolic materials used. This study was undertaken to investigate the histopathologic changes of embolized renal artery in rabbit by various embolic materials, according to each embolic material and to time passed by after embolization. Of the 5 arteries embolized by ethylene vinyl alcohol copolymer(EVAL), one showed abscess formation in embolized kidney. The other 4 allowed to perform further pathologic study: within a week after embolization there was no any specific change in vessels, however, minimal endothelial hypertrophy was observed following 2 weeks of embolization. Of the 8 renal arteries embolized by N-buthyl-2-cyanoacrylate(Histoacryl), 4 showed total occlusion of the main renal arteries as well as renal infarction, which reflects the strong adhesiveness of Histoacryl to vascular wall. The other 4 showed fibrinoid degeneration in vascular wall within a week. However, further change was not observed thereafter. In all the 5 renal arteries embolized by polyvinyl alcohol(Ivalon), there were infiltration of inflammatory cells along the vessel walls, within one week, which represents vasculitis. They showed some fibrosis with appearance of giant cells in the vessel wall two weeks after embolization and also showed marked fibrosis of connective tissues surrounding vessels two months after embolization, respectively. The results suggest that EVAL is useful for the embolization of hypervascular lesion with limited arteriovenous fistula, Histoacryl for the curative treatment of the lesion with high blood flow or severe arteriovenous fistula, and Ivalan for palliative treatment of malignant tumor or arteriovenous malformation, respectively.

Analysis of the result and merit of computed tomography guided percutaneous needle aspiration biopsy of focal lung lesion

Percutaneous needle biopsy of pulmonary lesion with use of fluoroscopic guidance is well established as a diagnostic tool but limited by the small size and inaccessibility of certain lesions. However, percutaneous needle biopsy has been used increasingly in relation to advance and the safty of smaller biopsy needle and new imaging modalities such as ultrasound and CT. CT, because of its characteristics of high resolution, allows tissue sampling with considerable safety from area that heretofore could not be visualized under fluoroscopy. The authors summarized 44 pulmonary lesions that underwent CT-guided transthoracic biopsy with fine-needle over a 14 month period and analyzed the sensitivity of PTNB. CT-guided PTNB was done with 20 gauge or 22 gauge Westcott biopoy needle(Manan medical products, USA). A diagnosis was made in 27 of 44 cases(61%) including malignany in 19 of 24 cases and benignancy in 8 of 20 cases. The pulmonary mass lesions were located at the peripheral zone of the lung field in 33 cases and at the central zone in 11 cases. Complications were observed in 2 cases which were pneumothorax and hemoptysis each but specific therapy was not required. The sensitivity of PTNB by one session was 61%(27/44). The sensitivity of malignancy was 79%(19/24) and benignancy was 40%(8/20). These results suggest the usefulness of PTNB using fine needles be increased in earlier diagnosis and improved staging of pulmonary nodular lesions without significant complications.