Radiation Doses of Various CT Protocols: a Multicenter Longitudinal Observation Study

Emerging concerns regarding the hazard from medical radiation including CT examinations has been suggested. The purpose of this study was to observe the longitudinal changes of CT radiation doses of various CT protocols and to estimate the long-term efforts of supervising radiologists to reduce medical radiation. Radiation dose data from 11 representative CT protocols were collected from 12 hospitals. Attending radiologists had collected CT radiation dose data in two time points, 2007 and 2010. They collected the volume CT dose index (CTDIvol) of each phase, number of phases, dose length product (DLP) of each phase, and types of scanned CT machines. From the collected data, total DLP and effective dose (ED) were calculated. CTDIvol, total DLP, and ED of 2007 and 2010 were compared according to CT protocols, CT machine type, and hospital. During the three years, CTDIvol had significantly decreased, except for dynamic CT of the liver. Total DLP and ED were significantly decreased in all 11 protocols. The decrement was more evident in newer CT scanners. However, there was substantial variability of changes of ED during the three years according to hospitals. Although there was variability according to protocols, machines, and hospital, CT radiation doses were decreased during the 3 years. This study showed the effects of decreased CT radiation dose by efforts of radiologists and medical society.

A Case of Severe Localized Reaction due to Extravasation of Contrast Media / 대한피부과학회지

Extravasation of contrast media into subcutaneous tissue is a relatively frequent complication. Although most patients complain of initial swelling, tightness, and burning pain at the site of extravasation, some experience little or no discomfort. In most cases, conservative management is recommended. However, severe injury after extravasation of contrast media have been reported, including skin ulceration, tissue necrosis, and compartment syndrome, in which cases surgical intervention should be considered. We report a case of a 53-year-old man who had severe localized reaction due to extravasation of contrast media for a follow-up brain CT scan after subarachnoid hemorrhage.

Pneumatosis Intestinalis with Hepatic Portal Venous Gas in a Hemodialysis Patient / 대한신장학회지

Pneumatosis intestinalis is an uncommon but important condition in which gas is found in a linear or cystic form in the submucosa or subserosa of the bowel wall. It occurs in several clinical settings in adults who have a wide variety of underlying disorders that determine prognosis. Especially, hepatic portal venous gas with pneumatosis intestinalis has been rarely described in chronic dialysis patients. We report a case of 53-year-old man with hemodialysis-dependent end stage renal disease who developed a pneumatosis intestinalis accompanied hepatic portal venous gas. This patient was treated conservatively with intravenous antibiotics, fluid therapy, and oxygen supply without surgical approach.

Image Quality Improvement after Implementation of a CT Accreditation Program

OBJECTIVE: The purpose of this study was to evaluate any improvement in the quality of abdominal CTs after the utilization of the nationally based accreditation program. MATERIALS AND METHODS: Approval was obtained from the Institutional Review Board, and informed consent was waived. We retrospectively analyzed 1,011 outside abdominal CTs, from 2003 to 2007. We evaluated images using a fill-up sheet form of the national accreditation program, and subjectively by grading for the overall CT image quality. CT scans were divided into two categories according to time periods; before and after the implementation of the accreditation program. We compared CT scans between two periods according to parameters pertaining to the evaluation of images. We determined whether there was a correlation between the results of a subjective assessment of the image quality and the evaluation scores of the clinical image. RESULTS: The following parameters were significantly different after the implementation of the accreditation program: identifying data, display parameters, scan length, spatial and contrast resolution, window width and level, optimal contrast enhancement, slice thickness, and total score. The remaining parameters were not significantly different between scans obtained from the two different periods: scan parameters, film quality, and artifacts. CONCLUSION: After performing the CT accreditation program, the quality of the outside abdominal CTs show marked improvement, especially for the parameters related to the scanning protocol.

Management of Anastomotic Leakage after Gastrointestinal Surgery Using Fluoroscopy-guided Foley Catheter

PURPOSE: The aim of this study is to present cases of postoperative leakage after various types of gastrointestinal operations that were successfully managed with fluoroscopy-guided Foley catheter. METHODS: Fluoroscopy-guided Foley catheter insertion and drainage methods were performed in 13 leakage sites of 10 patients diagnosed as having leakage after gastrointestinal operations such as esophagectomy, gastrectomy and appendectomy. Under fluoroscopic guidance, a guide-wire was inserted into the leakage site where a Foley catheter was then introduced over the guide wire, inserted and ballooned. RESULTS: The median time for the procedures was 30 minutes (range: 20~260 minutes), with esophagus or stomach leakage sites requiring a longer procedure time than the appendiceal or duodenal stump. The indwelling Foley catheters were successfully removed after a median of 11 days (range: 8~44 days), and the opening of the enterocutaneous fistulas were spontaneously closed in eight out of 10 patients. CONCLUSION: The application of this method showed good results and could be a useful method to manage leakage after gastrointestinal surgery, especially in patients with leakage from the stump of the duodenum or appendix.

Radiation Exposure to Physicians in the Emergency Department

PURPOSE: Emergency physicians (EP) are vulnerable to radiation exposure while on duty in the emergency department (ED). Although many studies have been reported abroad, there have been few studies of radiation exposure to EP in Korea. This study was performed to determine the present radiation exposure conditions of EP in Korea. METHODS: A prospective study was conducted from April 1, 2007 to June 30, 2007 at ED in three teaching hospitals. Eighteen interns and 19 residents were selected. Each wore thermoluminescent personal radiation dosimetry monitors at near the thyroid while working in the ED. We estimated the radiation exposure dose of these EP for three months and compared the results with those obtained for radiologists. RESULTS: The average radiation exposure dose of EP over three months was 0.257+/-0.391 mSv, and that of radiologists was 0.184+/-0.273 mSv. These results were below the recommended occupational dose limit of 5 mSv per 3 months. The radiation exposure dose of EP was higher than that of radiologists, but the difference was not statistically significant (0.280+/-0.303 vs 0.075+/-0.981 mSv, p=0.042). CONCLUSION: We recommend that the use of dosimetry by EP needs to be reviewed. EP should be aware of radiation exposure risks and minimize radiation exposure.

Carotid Doppler Ultrasound in Patients with Stenosis of the Intracranial Internal Carotid Artery

PURPOSE: To investigate the Doppler ultrasonographic parameters of a carotid ultrasound (CUS) for the stenosis of the intracranial internal carotid artery (IICA). MATERIALS AND METHODS: The authors evaluated 15 patients with normal extracranial ICA, the common carotid artery (CCA), and stenosis of IICA (patient group). The control group consisted of 22 patients with normal findings on a magnetic resonance angiography (control group). All subjects were subjected to a CUS, whereas subjects from the patient group underwent a cerebral angiography. The following parameters were investigated: peak systolic velocity (PSV) and end diastolic velocity (EDV) in ICA, PSV in CCA, resistive index (RI) in ICA, and PSV ratio. Stenosis was measured following an angiography and was graded as follows: normal (0-24%), mild (25-49%), moderate (50-69%), and severe (70-99%). Next, the CUS findings, which reflected the IICA stenosis, were investigated. RESULTS: Of the 74 ICAs, 52 were normal (44 ICAs in the normal group and 8 ICAs in the patient group), 10 had mild stenosis, 8 had moderate stenosis, and severe 4 had severe stenosis. As the stenosis grade increased, PSV and EDV in ICA as well as PSV in CCA, decreased (p value < 0.05); however, the PSV ratio and RI remained unchanged. CONCLUSION: As stenosis of IICA increases, PSV and EDV of ICA and PSV of CCA decreases following a CUS.

Fat-Containing Lesions in Vertebrae and Spinal Canal: A Pictorial Review

The recent development of image techniques, including computed tomography and magnetic resonance imaging, plays an important role in the diagnosis and treatment of spinal disease. A variety of lesions in the spine may contain fat tissue, and these lesions have the possibility of being benign or malignancy. The principle of treatment varies depending on the characteristics of the lesions. The purpose of this pictorial assay is to document the radiologic findings to help physicians make the correct diagnosis, to confirm the characteristics and the extent of the lesion, to anticipate the prognosis and to select and decide upon the therapeutic method when a fat-containing lesion is located in the spinal vertebrae and/or spinal canal.

Fat-Containing Lesions in Vertebrae and Spinal Canal: A Pictorial Review

The recent development of image techniques, including computed tomography and magnetic resonance imaging, plays an important role in the diagnosis and treatment of spinal disease. A variety of lesions in the spine may contain fat tissue, and these lesions have the possibility of being benign or malignancy. The principle of treatment varies depending on the characteristics of the lesions. The purpose of this pictorial assay is to document the radiologic findings to help physicians make the correct diagnosis, to confirm the characteristics and the extent of the lesion, to anticipate the prognosis and to select and decide upon the therapeutic method when a fat-containing lesion is located in the spinal vertebrae and/or spinal canal.

A Case of Sweet's Syndrome with Pulmonary Manifestation

Sweet's syndrome is a reactive process characterized by the abrupt onset of tender erythematous plaques and typical histological findings. Currently, the entity recognized as Sweet's syndrome ranges from classic Sweet's disease to a more aggressive neutrophilic process that may be associated with various diseases, malignancy and drug intakes. Also, extracutaneous manifestations of Sweet's syndrome have the potential to involve other organ systems. Pulmonary manifestation of Sweet's syndrome is rare and may be experienced as a cough, dyspnea, pleurisy or pulmonary infiltration upon chest X-ray. We, herein, report a 46-year-old woman with Sweet's syndrome who showed pulmonary infiltration and pleural effusion upon chest X-ray.

Polyvinyl Alcohol Embolization Adjuvant to Oily Chemoembolization in Advanced Hepatocellular Carcinoma with Arterioportal Shunts

OBJECTIVE: To assess the feasibility and safety of polyvinyl alcohol (PVA) embolization adjuvant to transarterial oily chemoembolization (P-TACE) in advanced hepatocellular carcinoma (HCC) with arterioportal shunts (APS). MATERIALS AND METHODS: Nineteen patients who underwent PVA embolization for APS before a routine chemoembolization (TACE) procedure were retrospectively reviewed. 10 of these 19 patients underwent follow-up TACE or P-TACE after P-TACE (Group A), but nine patients underwent only initial P-TACE because of progression of HCC and/or underlying liver cirrhosis (Group B). Hepatic function tests, APS grades, and portal flow directions were evaluated before and after P-TACE sessions. Complications after procedures and survival days were also evaluated. RESULTS: In group A, APS grade was improved in eight patients and five of six patients with hepatofugal flow showed restored hepatopetal flow postoperatively. No immediate complication was developed in either group. Transient hepatic insufficiency developed in eight (42.1%) of 19 patients after P-TACE, and seven (87.5%) of these eight recovered within two weeks under conservative care. The mean and median survival time all study subjects was 280 days and 162 days. CONCLUSION: P-TACE is feasible and safe in advanced HCC patients with APS.

Radiologic Findings of Neonatal Cerebral Infarction related with Portal Vein Thrombosis: Case Report

A cerebral infarction in a newborn infant is not uncommon and is major cause of neonatal seizure. The author encountered one case of cerebral infarction that was assumed to be related to a portal vein thrombosis, and reports the radiology findings of a neonatal cerebral infarction and portal vein thrombosis.

A Case of Doudenal Diaphragm in an Adult Treated with Endoscopic Membranotomy using Insulated Tip Electrosurgical Knife / 대한소화기내시경학회지

A duodenal diaphragm is rare congenital anomaly among the duodenal obstructions. Its symptoms and signs usually appear from birth if the obstruction is complete. However, a diagnosis may be delayed until the patient reaches adulthood in cases of an incomplete obstruction. Treatment of an adult duodenal diaphragm is usually surgical. To our knowledge, there are few reports of the endoscopic treatment of an adult duodenal diaphragm but none in Korea. We report a duodenal diaphragm in a 26- year-old female with epigastric pain, who was treated with an endoscopic membranotomy using an insulated tip knife.

Intrasellar Schwannoma: A Case Report

Schwannomas usually arise from sensory nerves, and most often from the vestibular component of the acoustic nerve. Intrasellar and parasellar schwannomas are exceedingly rare. It is difficult to distinguish them from typical pituitary macroadenomas because of their clinical and radiological resemblance. In this report, we present an unusual case of an intrasellar schwannoma with a suprasellar extension that radiographically simulated a pituitary macroadenoma.

Migration of a Slipped Aneurysmal Clip from the Intracranium into the Spinal Canal: Case Report

Very rarely, clips used for the ligation of intracranial aneurysms become detached and subsequently migrate into the spinal canal, causing lumbar pain or radiculopathy by compressing nerve roots or inducing inflammatory processes in their newly established location. However, it is easy to overlook the migration of the clip, because there may be either no noticeable symptoms, or a herniated disk may be mistakenly diagnosed as being the source of the present symptoms. Herein, the authors report a case in which an aneurysmal clip migrated into the spinal cord.

Maffucci's Syndrome Associated with Chondrosarcoma and Aneurysm: Case Report

Maffucci syndrome is a rare congenital non-inherited condition characterized by multiple enchondromas and cutaneous hemangiomas. It is associated with increased risk of malignancy, including chondrosarcomas, and because of generalized mesodermal dysplasia, aneurysms can develop. We present a case of Maffucci syndrome associated with intracranial chondrosarcoma and aneurysm.

MR Imaging of Skeletal Muscle Injury in Rabbit: Comparison bet ween Diffusion and T2-weighted MR Images

PURPOSE: The purpose of this study was to apply the diffusion-weighted MR imaging technique to the early detection of skeletal muscle injury and to evaluate the usefulness of this imaging sequence. MATERIALS AND METHODS: Thirty rabbits, divided into two groups, were included in this study. Skeletal muscle injury was experimentally induced in the right thigh muscles of each rabbit by clamping with a hemostat for one minute. Four-stage clamping was applied to the rabbits in group I, but for group II there was only one stage. Diffusion and T2-weighted MR images were obtained using a 1.5T MR unit. Serial 5-and 30-minute, and 2-, 24-, and 48- hour delayed images were obtained after injury. The initial time of signal intensity change was recorded and the signal intensities of the injured sites and corresponding normal sites were measured and compared. RESULTS: On 5-minute delayed images in group I, diffusion-weighted MR images showed signal intensity changes in injured muscle in all 15 cases, but on T2-weighted images, change was not detected in three cases. In group II, 5-minute delayed T2-weighted images failed to depict the lesion in six cases, but on diffusion-weighted images, all lesions were detected. In addition, one lesion was not detected on 30-minute delayed T2- weighted images. In group II, the sensitivity of lesion detection was significantly higher on diffusion-weighted than on T2-weighted images (p = 0.0169). CONCLUSION: Diffusion-weighted MR imaging was shown to be more sensitive than T2-weighted imaging for the detection of signal intensity changes immediately after artificial injury, especially when this was of a lesser degree. These results suggest that diffusion-weighted MR imaging may be useful for the detection of early stage skeletal muscle injury.

Three Cases of Acute Focal Bacterial Nephritis

Acute focal bacterial nephritis(AFBN) is an unusual form of localized renal infection, which has various imaging findings and should be distinguished from abscess or other renal masses. Clinical symptoms are similar to other urinary tract infections but the diagnosis needs a CT or sonographic confirmation. Treatment, which is nonoperative, consists of intensive antibiotic therapy. We report three cases of AFBN with urinary tract infection in an 11-month-old, 9-month-old female and 8-month-old male patients, respectively. The confirmative diagnosis was done by localized intrarenal solid mass lesion by sonography. They were treated with intravenous and oral antibiotics for 6, 4 and 2weeks, respectively. Follow-up urinalysis, urine culture and sonographic finding were normal after treatment.

Tuberculous Arthritis and Monoarticular Rheumatoid Arthritis in the Knee: Differential Diagnosis using MR Imaging

PURPOSE: To determine the extent to which magnetic resonance(MR) imaging findings can help differentiate between tuberculous arthritis (TA) and rheumatoid arthritis(RA). MATERIALS AND METHODS: This study involved sixteen patients with pathologically proven arthritis of the knee. In eight patients(mean age, 29.6 years; M:F=4:4) this was of the tuberculous variety, while eight (mean age, 47.5 years; M:F=2:6) suffered from the rheumatoid variety, which was monoarticular. For 14 patients, contrast enhancement studies were available. We retrospectively analyzed MR findings according to the demonstrated pattern of synovial thickening (regular and even, or irregular and nodular), bone erosion or abscess,bone marrow(BM) edema, the sites at which bursae were present, para-articular mass formation, and lymphadenopathy. RESULTS: In five of eight TA cases (62.5 %), irregular and nodular enhanced synovial thickening was present, while in six of eight RA cases (75%), thickening was regular and even. Bone erosions or subarticular abscesses were found in six TA cases (75%) and small erosions in three cases (37.5%) of RA. BM edema surrounding the erosion was found in four cases of TA (50%) and two of RA (25 %). In TA, edema was more extensive. In both TA and RA, all suprapatella bursae were distended while popliteal bursae were present in two cases of TA(25 %) and four of RA (50%). Para-articular masses with rim like enhancement were found in six cases of TA (75%) and in one case of RA (12.5 %). In particular, para-articular lymphadenopathy was seen in six cases of TA(75%), but not in RA. CONCLUSION: MR findings of irregular and nodular synovial thickening, extensive bone erosion, extensive BM edema, particular, para-articular abscess formation and ymphadenopathy, may help differentiate tuberculous arthritis of the knee from the rhumatoid variety.