Monitoring Radiation Doses during Diagnostic and Therapeutic Neurointerventional Procedures: Multicenter Study for Establishment of Reference Levels / 신경중재치료의학

Purpose@#To assess patient radiation doses during diagnostic and therapeutic neurointerventional procedures from multiple centers and propose dose reference level (RL). @*Materials and Methods@#Consecutive neurointerventional procedures, performed in 22 hospitals from December 2020 to June 2021, were retrospectively studied. We collected data from a sample of 429 diagnostic and 731 therapeutic procedures. Parameters including dose-area product (DAP), cumulative air kerma (CAK), fluoroscopic time (FT), and total number of image frames (NI) were obtained. RL were calculated as the 3rd quartiles of the distribution. @*Results@#Analysis of 1160 procedures from 22 hospitals confirmed the large variability in patient dose for similar procedures. RLs in terms of DAP, CAK, FT, and NI were 101.6 Gy·cm2, 711.3 mGy, 13.3 minutes, and 637 frames for cerebral angiography, 199.9 Gy·cm2, 3,458.7 mGy, 57.3 minutes, and 1,000 frames for aneurysm coiling, 225.1 Gy·cm2, 1,590 mGy, 44.7 minutes, and 800 frames for stroke thrombolysis, 412.3 Gy·cm2, 4,447.8 mGy, 99.3 minutes, and 1,621.3 frames for arteriovenous malformation (AVM) embolization, respectively. For all procedures, the results were comparable to most of those already published. Statistical analysis showed male and presence of procedural complications were significant factors in aneurysmal coiling. Male, number of passages, and procedural combined technique were significant factors in stroke thrombolysis. In AVM embolization, a significantly higher radiation dose was found in the definitive endovascular cure group. @*Conclusion@#Various RLs introduced in this study promote the optimization of patient doses in diagnostic and therapeutic interventional neuroradiology procedures. Proposed 3rd quartile DAP (Gy·cm2) values were 101.6 for diagnostic cerebral angiography, 199.9 for aneurysm coiling, 225.1 for stroke thrombolysis, and 412.3 for AVM embolization. Continual evolution of practices and technologies requires regular updates of RLs.

Multidetector CT Findings of Solid Organ Injury Based on 2018 Updated American Association for the Surgery of Trauma Organ Injury Scaling System

The newly revised 2018 Organ Injury Scale (OIS) has a similar format to the previous American Association for Surgery and Trauma (AAST) Emergency General Surgery Grading System, dividing the criteria for grading solid organ damage into three groups; imaging, operation, and pathology. The most significant alteration in the OIS system 2018 revision is the incorporation of multidetector CT (MDCT) findings of vascular injury including pseudoaneurysm and arteriovenous fistula. Similar to the previous OIS, the highest of the three criteria is assigned the final grade. In addition, if multiple grade I or II injuries are present, one grade is advanced for multiple injuries up to grade III. This pictorial essay demonstrates the MDCT findings of solid organ injury grades based on the 2018 OIS system.

Multidetector CT Findings of Solid Organ Injury Based on 2018 Updated American Association for the Surgery of Trauma Organ Injury Scaling System

The newly revised 2018 Organ Injury Scale (OIS) has a similar format to the previous American Association for Surgery and Trauma (AAST) Emergency General Surgery Grading System, dividing the criteria for grading solid organ damage into three groups; imaging, operation, and pathology. The most significant alteration in the OIS system 2018 revision is the incorporation of multidetector CT (MDCT) findings of vascular injury including pseudoaneurysm and arteriovenous fistula. Similar to the previous OIS, the highest of the three criteria is assigned the final grade. In addition, if multiple grade I or II injuries are present, one grade is advanced for multiple injuries up to grade III. This pictorial essay demonstrates the MDCT findings of solid organ injury grades based on the 2018 OIS system.

Lipiodol Pneumonitis Following Transcatheter Arterial Chemoembolization for Hepatocellular Carcinoma

Transcatheter arterial chemoembolization (TACE) is a useful palliative therapeutic modality for hepatocellular carcinoma (HCC). Postembolization syndromes, such as fever, abdominal pain, and elevated liver enzyme levels are commonly known complications of TACE. One post-TACE pulmonary complication, lipiodol pneumonitis, is rarely reported. Lipiodol pneumonitis after TACE appears to be associated with chemical injury due to accidental perfusion of lipiodol to the lung vasculature, promoted by arteriovenous shunts within the hypervascular HCC. Here, we report a 42-year-old man with unresectable HCC and hepatic vein thrombosis. The patient was initially treated with TACE. The following day after TACE, acute respiratory symptoms such as dyspnea and cough developed with decreased oxygen saturation. Chest X-ray and computed tomography showed multiple patches and diffuse ground-glass opacities in both lung fields, suggesting of lipiodol pneumonitis. The patient’s condition and radiologic abnormalities subsequently improved after 2 weeks of conservative treatment alone.

Complete Remission with Transarterial Chemoembolization in a Patient with Hepatocellular Carcinoma Who Showed Early Recurrence following Surgical Resection

Although surgical resection is a curative treatment option for solitary hepatocellular carcinoma, high recurrence rate contributes to dismal long-term prognosis after curative resection. Early recurrence within 2 years after surgery is associated with intrahepatic metastasis of primary tumor. Liver regeneration after hepatic resection can accelerate tumorigenesis in remnant liver. Treatment strategies for intrahepatic recurrence after curative resection include salvage transplantation, repeated resection, local ablation, and transarterial chemoembolization (TACE). Here, we report a 51-year-old male who was presented with a single large tumor located at segment 4. The patient was initially treated with surgical resection, but intrahepatic recurrence occurred only 4 months after surgery. He achieved complete remission with repeated TACE and has survived without recurrence for 4 years so far.

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

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.

Asymptomatic Emphysematous Pyelonephritis Incidentally Detected with Computed Tomography in a Diabetic Hemodialysis Patient / 대한내과학회지

Emphysematous pyelonephritis (EPN) is a necrotizing infection of the kidney with gas formation that can be fatal if it is not detected and treated promptly. Typical manifestations are high fever, flank pain, and shock. It typically occurs in patients with diabetes and, although rarely reported, in hemodialysis (HD) patients with or without diabetes. Furthermore, asymptomatic EPN has not yet been reported in HD patients. Here, we report a case of asymptomatic EPN in a diabetic HD patient incidentally detected with follow-up abdominal computed tomography after resection of colon cancer.

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

No abstract available.

A Case of Severe Arterial Steal Syndrome with Skin Necrosis Developing after Percutaneous Angioplasty / 대한내과학회지

Arterial steal syndrome is a rare but serious complication that disrupts antegrade flow distal to an arteriovenous fistula (AVF) because of excess blood flow through the AVF. A 65-year-old woman with diabetes mellitus and undergoing hemodialysis was admitted for coldness and pain in the right hand ipsilateral to an AVF. AVF stenosis had developed 6 months after an upper-arm AVF operation. These manifestations developed 2 days after a successful radiological intervention for a stenotic lesion in the AVF, which became worse until the skin on her hand ulcerated. The symptoms became aggravated, particularly during dialysis. Fistulography revealed that the AVF anastomosis site was patent but blood flow toward the forearm had decreased severely. Arterial steal syndrome developing after percutaneous angioplasty for an AVF stenosis was suspected, and the AVF was ligated, which resolved the hand pain and ulceration.

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 beta-lactamase-negative Escherichia coli.

Imaging of Distal Dural Ring Plane and Paraclinoid Internal Carotid Artery Aneurysms with 3D Rotational Angiography / 신경중재치료의학

PURPOSE: The distal dural ring (DDR) plane separates the intradural from extradural paraclinoid internal carotid artery (ICA) aneurysm. The purpose of this study was to evaluate the feasibility of the localization of the DDR plane drawn by the bony landmarks in patients with paraclinoid ICA aneurysms at 3D rotational angiography (3DRA). MATERIALS AND METHODS: 13 consecutive patients who underwent a 3DRA for the evaluation of 16 paraclinoid ICA aneurysms were reviewed retrospectively. On a dedicated workstation, multiplanar reconstruction (MPR) image along the virtual plane of DDR was reconstructed from the mask run image of 3DRA. Three bony landmarks were used to locate virtual plane of DDR: tuberculum sellae, inferior root of anterior clinoid process (ACP) and supero-medial aspect of optic strut. The MPR image was fused with 3D volume-rendered reconstruction image. Medial and posterior inclination angle of virtual plane of DDR was measured. The location of the paraclinoid ICA aneurysm was categorized into indradural, transdural, and extradural. RESULTS: In all cases, the DDR plane was identified and the relationship between the DDR plane and the paraclinoid ICA aneurysm was successfully determined on fusion image of 3DRA mask and contrast runs by dual volume visualization. The aneurysm locations determined with 3DRA were 8 intradural, 6 transdural and 2 extradural. The medial and posterior inclination angles of DDR plane ranged at 8 to 43degrees(mean 17.4degrees), and -2 to 20degrees(mean 6.4degrees), respectively. CONCLUSION: Localization of the paraclinoid ICA aneurysm in relation to the virtual plane of DDR is feasible with 3DRA and dual volume visualization.

Anatomical Variation of Internal Jugular Vein in Korean Hemodialysis Patients / 대한신장학회지

PURPOSE: The internal jugular vein (IJV) is a preferred site for central cannulation for hemodialysis (HD) because of its low incidence of central vein stenosis. Although anatomically IJV is commonly located on the anterior-lateral side of the carotid artery, some patients have anatomical variation of IJV, which can lead to difficulty and complication of cannulation. This study was performed to evaMETHODS: We enrolled 358 patients receiving IJV catheter cannulation for HD using doppler ultrasonography between January 2007 and February 2009. We examined the anatomical positions of IJV in relation to the position of carotid artery (CA) and incidence of anatomical variation on both sides. We also investigated incidence of inadequate IJV for cannulation, RESULTS: The mean age of 358 enrolled patients was 57+/-15 years (14-88 years) (M:F=203:155). Anatomical variations of the left (Lt) and right (Rt) IJV position relative to the CA were found in 36.3% and 27.1%, respectively. Various anatomical variations of IJV position were discovered in the anterior side (Lt 23.7%, Rt 21.2%), anterior-medial side (Lt 7%, Rt 2.5%), and the lateral side (Lt 1.1%, Rt 1.7%) relative to CA. Inadequate Lt and Rt IJVs for cannulation, which can be too small sized or obstructed, were 6.4% and 2.8%, respectively. CONCLUSION: About one third of Korean HD patients had anatomical variations of IJV position relative to the CA. This study supports the use of doppler ultrasound guided technique for IJV cannulation in HD patients.

Arteriovenous Fistula Dysfunction due to Stent Fracture in the Cephalic Arch / 대한신장학회지

Stent placement is widely used for vascular access stenosis in hemodialysis patients as well as coronary artery stenosis. As its complication, stent fracture is not uncommon and causes restenosis after stent placement in coronary artery stenosis, but it has been rarely reported in venous stenosis of hemodialysis patients. Here we report a case of arteriovenous fistula dysfunction due to stent fracture in the cephalic arch of a hemodialysis patient.

A Case of Central Vein Stenosis Complicated by Calcified Lesions of Pulmonary Tuberculosis / 대한신장학회지

Central venous stenosis or occlusion is commonly associated with placement of central venous catheters or devices. Although rare, central venous stenosis or occlusion may also develop without a history of previous central venous catheter placement. Here we report a case of central venous stenosis without a previous central catheter placement. A 76-year-old woman with hypertensive nephropathy was admitted due to deterioration of renal function. Tunneled cuffed catheter for hemodialysis was inserted in the right external jugular vein, and we intended to insert central venous catheter because of poorly functioning peripheral vein. But, left internal jugular vein was not cannulated. The patients had a history of pulmonary tuberculosis and chest x-ray revealed extensive calcified lesions mainly in left upper lung. Venography and CT angiogram showed complete occlusion at the confluent point of the left subclavian vein and left internal jugular vein, and left brachiocephalic vein by calcified lesion. The anterior cervical vein and jugular venous arch forming an anastomosis between the neck vein were marked dilated. The patient did not show any clinical symptoms and signs associated with central venous stenosis, and the central venous catheter functioned well, correction of central vein stenosis was not necessary. After the supportive care including temporary hemodialysis, the patient improved from renal dysfunction.

Successful Angioplasty of Arteriovenous Graft Obstruction Using Gadolinium chelate in a Patient with Iodine Hypersensitivity / 대한신장학회지

Percutaneous transluminal angioplasty (PTA) using iodine contrast dye has been used as the definitive method of choice for treating hemodialysis vascular access dysfunction. Occasionally, iodine material can not be used in the hemodialysis patients with a history of severe hypersensitivity reactions or the predialysis patients with premature access awaiting hemodialysis treatment. Gadolinium chelates have been reported as an alternative contrast agent for angiography or angioplasty in such patients. Here we report a case of successful angioplasty of arteriovenous graft obstruction using gadolinium chelate (gadopentetate dimeglumine) in a patient with repetitive iodine hypersensitivity reactions.

Huge Infected Thrombus of Right Atrium Related to Hemodialysis Catheter / 대한신장학회지

There has been an increase in the use of central venous catheters for temporary hemodialysis. Infected thrombus of right atrium is a rare but life-threatening complication of the central venous catheterization. A 35-year-old female hemodialysis patient was admitted with fever and dyspnea. She had been inserted tunneled hemodialysis catheter 2 months before. Blood cultures revealed methicillin- resistant Staphylococcus aureus. Chest CT showed multi-focal pneumonia and 4 cm sized huge thrombus in the right atrium. Echocardiography demonstrated same thrombus attached to the catheter tip in the right atrium. The catheter could not be removed because of high risk of pulmonary thromboembolism. Despite intravenous vancomycin treatment, the patient died from esophageal varix bleeding.

CT-guided Aspiration of Syringomyelia Involving Thoracic Spinal Cord: a Case Report / 신경중재치료의학

We present a case of symptomatic syringomyelia involving the spinal cord, which was managed by repeated CT-guided percutaneous aspiration, achieving significant decompression by imaging and clinical improvement of lower extremity numbness and weakness. Symptomatic syringomyelia, however, recurred on follow-up, and percutaneous aspiration was repeated four times at the average duration of 22 months. In no aspiration procedure did the patient experienced periprocedural complication. CT-guided percutaneous drainage of syringomyelia is a safe technique, and can be repeated as therapeutic alternative to surgery with temporary improvement of the symptom.

The Endovascular Management of Saccular Posterior Inferior Cerebellar Artery Aneurysms

OBJECTIVE: The purpose of this retrospective study was to report the outcome of the endovascular treatment of eight patients with eight saccular posterior inferior cerebellar artery (PICA) aneurysms. MATERIALS AND METHODS: Over the last seven years (1999-2006), eight consecutive patients with saccular PICA aneurysms were treated by endovascular methods. Five of the aneurysms were presented with subarachnoid hemorrhaging, whereas three were discovered incidentally. Four of the aneurysms (3 ruptured and 1 incidental) were treated by intrasaccular coiling, whereas the remaining four (1 ruptured and 3 incidental) were treated by vertebral artery (VA) occlusion. RESULTS: Of the four aneurysms treated by intrasaccular coiling, three were completely packed with coils and one was partially packed. In three of four patients who underwent vertebral artery occlusions, follow-up digital subtraction angiographies demonstrated thrombosed aneurysms and PICA. No procedure-related morbidity occurred and no re-bleed was encountered during a follow-up examination (mean; 31 months). CONCLUSION: As a result of this study, we found that the endovascular management of saccular PICA aneurysms should be considered as safe and effective.

Percutaneous Embolization of Renal Artery Pseudoaneurysm after Laparoscopic Partial Nephrectomy for Renal Cell Carcinoma / 대한비뇨기과학회지

Currently, partial nephrectomy for patients with malignant renal tumors has become the procedure of choice for elective indications. Attempts have been made to use minimally invasive endoscopic procedures to replace the standard open partial nephrectomy. Laparoscopic partial nephrectomy can be technically challenging and be associated with vascular complications such as pseudoaneurysm. We report here on a case of renal artery pseudoaneurysm that occurred after laproscopic partial nephrectomy for renal cell carcinoma treated by percutaneous selective angioembolization.

Giant Vertebrobasilar Junction Aneurysm Treated with Proximal Occlusion of Parent Artery Followed by Coil Embolization of Partially Thrombosed Aneurysm: A Case Report / 신경중재치료의학

In the case of giant vertebrobasilar junction aneurysm with an outflow directly draining into the basilar artery, trapping of ipsilateral vertebral artery is technically challenging. Endosaccular coil embolization may be an option, but it may aggravate symptoms due to mass effect or aneurysmal regrowth after coil compaction. Occlusion of the ipsilateral vertebral artery proximal to the aneurysm may be another option. However, complete thrombosis should be eventually achieved to prevent symptom progression from the retrograde flow or mass effect by the partial thrombosis within the aneurysm. The authors describe a case of giant vertebrobasilar aneurysm initially treated with proximal occlusion. As the aneurysm getting partial thrombosis, the bulbar compression symptom was slowly aggravated. We performed endosaccular coiling of small remaining sac 2 months later, which resulted in complete resolution of compression symptom.