Yoo Dong Won

Parenchymal Neurocutaneous Melanosis in Association with Intraventricular Dermoid and Dandy-Walker Variant: A Case Report

Neurocutaneous melanosis (NCM) is a rare congenital disease that is characterized by the presence of large or multiple congenital melanocytic nevi and melanotic lesions of the central nervous system. We report here on the CT and MR imaging findings of an unusual case of NCM that was associated with intraventricular dermoid and Dandy-Walker malformation.

Patient Radiation Exposure During Diagnostic and Therapeutic Procedures for Intracranial Aneurysms: A Multicenter Study

Purpose To assess patient radiation doses during cerebral angiography and embolization of intracranial aneurysms across multi-centers and propose a diagnostic reference level (DRL). Materials and Methods We studied a sample of 490 diagnostic and 371 therapeutic procedures for intracranial aneurysms, which were performed at 23 hospitals in Korea in 2015. Parameters including dose-area product (DAP), cumulative air kerma (CAK), fluoroscopic time and total angiographic image frames were obtained and analyzed. Results Total mean DAP, CAK, fluoroscopy time, and total angiographic image frames were 106.2 ± 66.4 Gy-cm2, 697.1 ± 473.7 mGy, 9.7 ± 6.5 minutes, 241.5 ± 116.6 frames for diagnostic procedures, 218.8 ± 164.3 Gy-cm2, 3365.7 ± 2205.8 mGy, 51.5 ± 31.1 minutes, 443.5 ± 270.7 frames for therapeutic procedures, respectively. For diagnostic procedure, the third quartiles for DRLs were 144.2 Gy-cm2 for DAP, 921.1 mGy for CAK, 12.2 minutes for fluoroscopy times and 286.5 for number of image frames, respectively. For therapeutic procedures, the third quartiles for DRLs were 271.0 Gy-cm2 for DAP, 4471.3 mGy for CAK, 64.7 minutes for fluoroscopy times and 567.3 for number of image frames, respectively. On average, rotational angiography was used 1.5 ± 0.7 times/session (range, 0-4; n=490) for diagnostic procedures and 1.6 ± 1.2 times/session (range, 0-4; n=368) for therapeutic procedures, respectively. Conclusion Radiation dose as measured by DAP, fluoroscopy time and image frames were lower in our patients compared to another study regarding cerebral angiography, and DAP was lower with fewer angiographic image frames for therapeutic procedures. Proposed DRLs can be used for quality assurance and patient safety in diagnostic and therapeutic procedures.

Retrospective Review of Angiography before Cannulation of Newly Created Vascular Accesses in Hemodialysis Patients

PURPOSE To investigate vascular access status before first cannulation and the clinical implications of angiography performed before cannulation. MATERIALS AND METHODS A retrospective review of 300 consecutive patients who underwent angiography after vascular access surgery and before cannulation between August 2004 and April 2010 was performed. Angiography was performed 4-6 weeks after the surgery but before the first cannulation. RESULTS Angiography revealed 94 (31.3%) cases of severe stenosis (≥ 50% luminal narrowing) that required percutaneous transluminal angioplasty (PTA) or a second operation. No stenosis was observed in 122 (40.7%) cases, and mild stenosis (< 50% luminal narrowing) was observed in 84 (28%) cases. For the 94 cases with severe stenosis, PTA was performed in 66, and a second operation was performed in 16. In the other cases (n = 12), HD was maintained by a permanent catheter, or the patients were transferred to another institution. PTA was an immediate success in all patients who underwent the procedure except two. Of 84 patients with mild stenosis, 70 were followed for 1 year; vascular access dysfunction occurred in 15, and 11 of these underwent successful PTA. Of the 122 patients with normal angiographic findings, 102 were followed for 1 year, and vascular access dysfunction did not occur in any of these patients. CONCLUSIONS Early postoperative angiography before the first hemodialysis is helpful for the early detection and treatment of vascular access dysfunction.

20-Year History of Korean Society of Interventional Neuroradiology (KSIN)

In 1994, at 19:00 on August 30th, eight radiologists pursuing the area of interventional neuroradiology individually returned from overseas conference and gathered at the Sujeong Palace in Dongsung-dong, Seoul for the first time. They were Dr. Dong Ik Kim, Dr. Sun Yong Kim, Dr. Hong Sik Byun, Dr. Dae Chul Suh, Dr. Hae Young Seol, Dr. Gil Woo Lee, Dr. Nam Joon Lee, and Dr. Moon Hee Han whose common interest in interventional neuroradiology research created the Korean Society of Interventional Neuroradiology (KSIN). At the gathering, a number of mandates were initiated: 1) the name of the society would be called ‘A Society of Interventional Neuroradiologic Research’, 2) a monthly meeting would be held on 2nd Mondays of each month at 18:30 in the conference room of Samsung Medical Center, 3) Dr. Hong Sik Byun of Samsung Medical Center would be responsible (not as president yet) for contacting other members for the monthly meeting, 4) a monthly membership fee would be 50,000 Korean Won (KRW), 5) initial monthly meetings would be mainly based on case discussions, and 6) the monthly meeting would be open to any radiologist interested in interventional neuroradiology. In the early days, the members faced a number of diff iculties; individual purchases of expensive up-to-date medical equipment and products needed for interventional procedures from overseas were common as most equipment and products available at the time were insufficient and imported goods were limited. To make things worse, the national health insurance did not provide coverage for most of the new procedures in the f ield of interventional neuroradiology and it was up to the interventional radiologists to overcome such difficulties and make progress. The first monthly meeting was held on Monday of September 12th, 1994 in the conference room at Samsung Medical Center. A total of four meetings were held during that year, ending with a well-deserved end of year celebration in December 1994. The KSIN’s first international involvement was at the 1st conference of the Asian Australian Federation of Interventional and Therapeutic Neuroradiology (AAFITN) held during October 2nd-6th, 1994 in Beijing, China where Dr. Dong Ik Kim, one of the co-founders of KSIN, had participated. More international participations of KSIN followed. Dr. Dong Ik Kim was the congress administrator of the 3rd World Federation of Interventional and Therapeutic Neuroradiology (WFITN) held in Kyoto, Japan on November 19th-22nd, 1995. Dr. Sun Yong Kim and Dr. Moon Hee Han gave oral presentation and displayed poster exhibition respectively, for which Dr. Han received the award for best poster presentation. In September 1996, Dr. Hae Young Seol of Guro

Emphysematous pyelonephritis initially presenting as a spontaneous subcapsular hematoma in a diabetic patient

Emphysematous pyelonephritis (EPN) is a life-threatening infection characterized by the formation of gas. Complications of EPN include septic shock, acute renal failure, and disseminated intravascular coagulation. Spontaneous subcapsular hematoma (SCH) has also been reported as a rare complication of EPN, although there have been no reports to date of this occurring prior to the presentation of EPN. We report a case of EPN that initially presented as spontaneous SCH. The patient was admitted for left flank pain, and initial computed tomography revealed SCH without any air shadows. Laboratory findings and clinical symptoms suggested the presence of urinary tract infection and the patient was started on antibiotics. Fever developed 24 hours after admission. On follow-up computed tomography 7 days later, EPN was newly observed, and a percutaneous drain was inserted. Blood, urine, and drainage fluid cultures all revealed growth of extended-spectrum β-lactamase-negative Escherichia coli.