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1.
Korean Journal of Radiology ; : 345-354, 2017.
Article in English | WPRIM | ID: wpr-36764

ABSTRACT

OBJECTIVE: Although a transjugular intrahepatic portosystemic shunt (TIPS) is commonly placed to manage isolated gastric varices, balloon-occluded retrograde transvenous obliteration (BRTO) has also been used. We compare the long-term outcomes from these procedures based on our institutional experience. MATERIALS AND METHODS: We conducted a retrospective review of patients with isolated gastric varices who underwent either TIPS with a covered stent or BRTO between January 2000 and July 2013. We identified 52 consecutive patients, 27 who had received TIPS with a covered stent and 25 who had received BRTO. We compared procedural complications, re-bleeding rates, and clinical outcomes between the two groups. RESULTS: There were no significant differences in procedural complications between patients who underwent TIPS (7%) and those who underwent BRTO (12%) (p = 0.57). There were also no statistically significant differences in re-bleeding rates from gastric varices between the two groups (TIPS, 7% [2/27]; BRTO, 8% [2/25]; p = 0.94) or in developing new ascites following either procedure (TIPS, 4%; BRTO, 4%; p = 0.96); significantly more patients who underwent TIPS developed hepatic encephalopathy (22%) than did those who underwent BRTO (0%, p = 0.01). There was no statistically significant difference in mean survival between the two groups (TIPS, 30 months; BRTO, 24 months; p = 0.16); median survival for the patients who received TIPS was 16.6 months, and for those who underwent BRTO, it was 26.6 months. CONCLUSION: BRTO is an effective method of treating isolated gastric varices with similar outcomes and complication rates to those of TIPS with a covered stent but with a lower rate of hepatic encephalopathy.


Subject(s)
Humans , Ascites , Esophageal and Gastric Varices , Hepatic Encephalopathy , Hypertension, Portal , Methods , Portasystemic Shunt, Surgical , Retrospective Studies , Stents
2.
Gastrointestinal Intervention ; : 156-158, 2016.
Article in English | WPRIM | ID: wpr-167187

ABSTRACT

Summary of Event: A transjugular intrahepatic portosystemic shunt (TIPS) stent (Viatorr) was misplaced into main portal vein and superior mesenteric vein. This misplaced covered stent was then successfully retrieved using the rigid endobronchial forceps. Teaching Point: Before release the covered portion of the TIPS stent (Viatorr), it is necessary to confirm the position of uncovered portion in portal vein and covered portion in parenchymal tract. The endobronchial forceps technique is a safe and efficient method for retrieving a misplaced TIPS stent.


Subject(s)
Device Removal , Mesenteric Veins , Methods , Portal Vein , Portasystemic Shunt, Surgical , Portasystemic Shunt, Transjugular Intrahepatic , Stents , Surgical Instruments
3.
Gastrointestinal Intervention ; : 170-176, 2016.
Article in English | WPRIM | ID: wpr-184920

ABSTRACT

Transjugular intrahepatic portosystemic shunts (TIPS) are widely used in the management of bleeding gastric varices (GV). More recently, several studies have demonstrated balloon-occluded retrograde transvenous obliteration (BRTO) as an effective treatment method for bleeding isolated GV, especially in patients with contraindications for a TIPS placement. Both TIPS and BRTO can effectively treat bleeding GV with low rebleeding rates. Careful patient selection for TIPS and BRTO procedures is required to best treat the patient's individual clinical situation.


Subject(s)
Humans , Balloon Occlusion , Embolization, Therapeutic , Esophageal and Gastric Varices , Hemorrhage , Methods , Patient Selection , Portasystemic Shunt, Surgical , Portasystemic Shunt, Transjugular Intrahepatic
4.
Korean Journal of Radiology ; : 108-113, 2014.
Article in English | WPRIM | ID: wpr-114850

ABSTRACT

This report describes two non-cirrhotic patients with portal vein thrombosis who underwent successful balloon occlusion retrograde transvenous obliteration (BRTO) of gastric varices with a satisfactory response and no complications. One patient was a 35-year-old female with a history of Crohn's disease, status post-total abdominal colectomy, and portal vein and mesenteric vein thrombosis. The other patient was a 51-year-old female with necrotizing pancreatitis, portal vein thrombosis, and gastric varices. The BRTO procedure was a useful treatment for gastric varices in non-cirrhotic patients with portal vein thrombosis in the presence of a gastrorenal shunt.


Subject(s)
Adult , Female , Humans , Middle Aged , Balloon Occlusion/methods , Crohn Disease/surgery , Esophageal and Gastric Varices/therapy , Mesenteric Veins , Pancreatitis, Acute Necrotizing/complications , Portal Vein , Venous Thrombosis/complications
5.
Korean Journal of Radiology ; : 789-796, 2013.
Article in English | WPRIM | ID: wpr-209694

ABSTRACT

OBJECTIVE: To evaluate the outcomes of patients undergoing percutaneous placements of a biliary stent for obstructive jaundice secondary to metastatic gastric cancer after gastrectomy. MATERIALS AND METHODS: Fifty patients (mean age, 62.4 years; range, 27-86 years) who underwent percutaneous placements of a biliary stent for obstructive jaundice secondary to metastatic gastric cancer after gastrectomy were included. The technical success rate, clinical success rate, complication rate, stent patency, patient survival and factors associated with stent patency were being evaluated. RESULTS: The median interval between the gastrectomy and stent placement was 23.1 months (range, 3.9-94.6 months). The 50 patients received a total of 65 stents without any major procedure-related complications. Technical success was achieved in all patients. The mean total serum bilirubin level, which had been 7.19 mg/dL +/- 6.8 before stent insertion, decreased to 4.58 mg/dL +/- 5.4 during the first week of follow-up (p < 0.001). Clinical success was achieved in 42 patients (84%). Percutaneous transhepatic biliary drainage catheters were removed from 45 patients (90%). Infectious complications were noted in two patients (4%), and stent malfunction occurred in seven patients (14%). The median stent patency was 233 +/- 99 days, and the median patient survival was 179 +/- 83 days. Total serum bilirubin level after stenting was an independent factor for stent patency (p = 0.009). CONCLUSION: Percutaneous transhepatic placement of a biliary stent for obstructive jaundice secondary to metastatic gastric cancer after gastrectomy is a technically feasible and clinically effective palliative procedure.


Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Bile Duct Neoplasms/complications , Bile Ducts, Extrahepatic/surgery , Follow-Up Studies , Gastrectomy , Jaundice, Obstructive/diagnosis , Prosthesis Design , Retrospective Studies , Stents , Stomach Neoplasms/complications , Treatment Outcome
6.
Journal of the Korean Radiological Society ; : 141-147, 2008.
Article in Korean | WPRIM | ID: wpr-151891

ABSTRACT

PURPOSE: To perform a frequency analysis of the extracolonic findings (ECF) of the CT colonography between symptomatic and asymptomatic patients. MATERIALS AND METHODS: Seventy-two consecutive symptomatic patients and sixty-three consecutive asymptomatic patients who underwent CT colonography were enrolled in this study. Non-contrast enhanced axial images were reviewed retrospectively to identify the ECF and classified them as major, moderate or minor important findings according to their potential clinical importance. The frequencies of each classification and ECF were analyzed and compared between two groups (symptomatic and asymptomatic). RESULTS: Eighty-two ECF were identified in 49 (68.1%) of the 72 symptomatic patients. The findings were classified as follows: major (8/49, 11.1%), moderate (17/49, 23.6%), minor (39/49, 54.2%). Sixty ECF were detected in 38 (60.3%) of the 63 asymptomatic patients. The findings were classified as follows: major (2/38, 3.2%), moderate (7/38, 11.1%), minor finding (35/63, 55.6%). No statistically significant differences were found between the two groups (p > 0.05) for the overall ECF frequency. However, a significantly higher frequency of major or moderate ECF was observed in symptomatic patients (30.6%) compared to asymptomatic patients (12.7%) (p < 0.05). CONCLUSION: The overall ECF frequency was similar between symptomatic and asymptomatic patients; however, the frequency of clinically important ECF (major or moderate) was higher in symptomatic patients, compared to asymptomatic patients. This result suggests that the major or moderate ECF required a further work up or treatment in symptomatic patients.


Subject(s)
Humans , Colonography, Computed Tomographic , Incidental Findings , Mass Screening , Retrospective Studies , Tomography, X-Ray Computed
7.
Korean Journal of Nephrology ; : 485-490, 2007.
Article in Korean | WPRIM | ID: wpr-216424

ABSTRACT

Tuberous sclerosis (TSC) is a systemic, autosomal dominant disorder resulting from mutations in one of two genes, TSC1 (encoding hamartin) or TSC2 (enconding tuberin). TSC causes seizure, mental retardation and hamartomatous tumors in multiple organs, including facial angiofibromas, cortical tubers, pulmonary lymphangiomatosis, renal angiomyolipomas and polycystic kidney disease. Renal angiomyofibromas may cause serious complications such as life threatening retroperitoneal hemorrhage or hematuria. The following is a report concerning a 41-year-old man with TSC who suffered spontaneous hemorrhage within the angiomyofibroma of the left kidney and underwent curative selective renal embolization. Then larger angiomyolipoma was suggested to be more likely to bleed, so secondary prophylactic selective renal embolization was done into five angiomyolipomas of the right kidney. After selective embolization, tumor size decreased and renal function was preserved. This patient did not show neurologic abnormality and family history of tuberous sclerosis. However, the brain magnetic resonance imaging revealed typical signs of tuberous sclerosis, and the computerized tomography of the abdomen showed bilateral renal angiomyolipomas and polycystic renal lesion. Herein we present a rare case of bilateral renal angiomyolipomas with spontaneous hemorrhage and preserved renal function after curative and prophylactic selective embolization.


Subject(s)
Adult , Humans , Abdomen , Angiofibroma , Angiomyolipoma , Brain , Hematuria , Hemorrhage , Intellectual Disability , Kidney , Magnetic Resonance Imaging , Polycystic Kidney Diseases , Seizures , Tuberous Sclerosis
8.
Journal of the Korean Radiological Society ; : 327-330, 2007.
Article in English | WPRIM | ID: wpr-42913

ABSTRACT

The reported incidence of spontaneous rupture of primary hepatocellular carcinoma (HCC) is up to 14.5%. However, rupture of the metastatic lesions of HCC is very rare. We describe here a case of massive retroperitoneal hemorrhage due to spontaneous rupture of right adrenal gland metastasis that was secondary to invasive HCC. This was successfully controlled by performing transcatheter arterial embolization (TAE).


Subject(s)
Adrenal Glands , Carcinoma, Hepatocellular , Hemorrhage , Incidence , Neoplasm Metastasis , Retroperitoneal Space , Rupture , Rupture, Spontaneous
9.
Journal of the Korean Radiological Society ; : 545-548, 2007.
Article in English | WPRIM | ID: wpr-32234

ABSTRACT

A 64-year-old man who underwent right hemicolectomy 3.5 years ago for ascending colon cancer and then RF ablation for two metastatic nodules in the liver was admitted to our hospital with a new metastatic nodule in the S6/7 segment of the liver. The CT scan showed a low attenuating metastatic nodule 2.2 cm in diameter in the S6/7 segment of the liver, and the liver showed peripheral bile duct dilatation. This nodule was treated with percutaneous RF ablation. A follow-up CT seven months after RF ablation showed the presence of a viable tumor in the RF ablation zone, with tumor extension along the dilated bile duct. These findings were confirmed on the resected specimen.


Subject(s)
Humans , Middle Aged , Bile Ducts , Colon , Colon, Ascending , Colonic Neoplasms , Dilatation , Follow-Up Studies , Liver Neoplasms , Liver , Neoplasm Metastasis , Neoplasm Recurrence, Local , Tomography, X-Ray Computed
10.
Journal of the Korean Hip Society ; : 16-20, 2007.
Article in Korean | WPRIM | ID: wpr-727149

ABSTRACT

PURPOSE: This study evaluated the short-term results of ceramic articulation total hip arthroplasty in cementless total hip arthroplasty. MATERIALS AND METHODS: 142 hips were followed-up for more than 2 years after cementless total hip arthroplasty using ceramic-on-ceramic articulation. The mean age and follow-up period was 58.3 years and 3.0 years, respectively. The Harris hip score and postoperative hip pain were analyzed clinically. The radiological results were assessed using various radiological indices. RESULTS: At the last follow-up, the Harris hip score improved from 58.1 points preoperatively to 93.2 points postoperatively. There were 4 cases (2.8%) of significant hip pain. Radiologically, all the stems demonstrated stable fixation. The inclination of the acetabular cup was changed significantly in 2 cases (1.4%), which were diagnosed as being loosened. A radiolucent line was observed around the stem in 9 cases (6.3%), and around the cup in 3 (2.1%). Endosteal new bone formation was observed around the stem in 50 cases (35%), and around the cup in 55 (38.5%). No osteolysis was observed around the stem and the cup. CONCLUSION: The short-term results of ceramic on ceramic articulation hip arthroplasty were excellent without osteolysis.


Subject(s)
Acetabulum , Arthroplasty , Arthroplasty, Replacement, Hip , Ceramics , Follow-Up Studies , Hip , Osteogenesis , Osteolysis
11.
Journal of the Korean Radiological Society ; : 243-251, 2007.
Article in Korean | WPRIM | ID: wpr-205287

ABSTRACT

PURPOSE: To compare the lesion conspicuity of radiofrequency ablation (RFA) zones among MR sequences according to time in the normal rabbit liver. MATERIALS AND METHODS: RFA zones were created in 12 rabbit livers with a 17-gauge internally cooled electrode (1-cm active tip, 30 Watts, 3 minutes). Three rabbits were sacrificed immediately, three days, two weeks, and six weeks after the RFA procedure, respectively. Before sacrifice, T1-, T2-weighted images (WI), and gadolinium-enhanced (GE)-T1WI images were obtained. The lesion conspicuity of the RFA zone and the contrast-to-noise ratio (CNR) of the RFA zone to the liver parenchyma were analyzed and compared among the MR sequences according to time. RESULTS: On T1WI, the RFA zones were only clearly seen on acute phase. On T2WI, the RFA zones were clearly seen on all phases except the hyperacute phase. On GE T1WI, the RFA zones were clearly seen on all phases. The CNRs of the RFA zone to the liver parenchyma of GE-T1WI (8.1-12.4) were significantly higher than the CNRs of TIWI (1.6-2.7) and T2WI (1.7-6.3) on all phases (p < 0.05), but the visual lesion conspicuity between GE T1WI and T2WI were similar. CONCLUSION: On hyperacute phase, GE T1WI showed better lesion conspicuity of the RFA zone than T1WI and T2WI. On other phases, GE T1WI and T2WI showed similar lesion conspicuity.


Subject(s)
Rabbits , Catheter Ablation , Electrodes , Liver , Radiology, Interventional
12.
Journal of Korean Foot and Ankle Society ; : 216-220, 2007.
Article in Korean | WPRIM | ID: wpr-161332

ABSTRACT

PURPOSE: To evaluate the effectiveness of percutaneous transluminal angioplasty (PTA) below the knee as a treatment in diabetic foot gangrene. MATERIALS AND METHODS: Between May 2003 and May 2006, angiography was performed in 35 diabetic foot gangrene classified as either Wagner grade IV or V. Infrapopliteal PTA was performed in 10 patients among them. Clinical success was defined as prevention of major amputation. RESULTS: Among 25 patients who did not receive infrapopliteal PTA, the major amputation rate is 22% (in one arterial occlusion cases), 50% (in two arterial occlusion cases), 63% (in three arterial occlusion cases), respectively. Infrapopliteal PTA was successfully performed in 8 among 10 patients. Two patients were failed and undergone below-knee amputation. Toe amputation were performed in 2 patients with one arterial occlusion. Out of 6 patients with three arterial occlusions, toe amputations were performed in 4 patients and the other 2 patients were healed through debridement. CONCLUSION: As a first choice revascularization procedure for limb salvage in diabetic foot gangrene, infrapopliteal PTA can be one of treatment options.


Subject(s)
Humans , Amputation, Surgical , Angiography , Angioplasty , Debridement , Diabetic Foot , Gangrene , Knee , Limb Salvage , Toes
13.
The Journal of the Korean Orthopaedic Association ; : 476-482, 2006.
Article in Korean | WPRIM | ID: wpr-646502

ABSTRACT

PURPOSE: To investigate and define the clinical results and prognostic factors affecting surgical outcome of the various etiologies of a cervical myelopathy. MATERIALS AND METHODS: Forty-one cervical myelopathy patients, who underwent surgery from March 1997 to March 2004, were retrospectively reviewed. The patients were divided into three groups according to the cause, HIVD (10 cases, group A), OPLL (14 cases, group B), cervical spondylotic myelopathy (17 cases, group C). An anterior cervical discectomy and fusion was carried out on one or two segments in group A, and an expansive open-door laminoplasty was performed in groups B and C. The correlations between age, onset, preoperative JOA score, signal change in the cord on the T2 weighted image MRI, compression ratio, which are known etiologies of myelopathy, and the recovery rate according to causes were analyzed. RESULTS: The mean preoperative and postoperative JOA score was 11.2 and 14.6 respectively. The mean recovery rate was 61.7%. There was no significant difference in the preoperative JOA score in each group (11.40 in group A, 11.93 in group B, 10.53 in group C). The recovery rate was ranked as follows: group A, B, and C (group A 75.98%, group B 61.39%, group C 53.61%) but the difference was not significant. Age, preoperative JOA score, signal change on T2WI MRI in group A (p<0.05), age, preoperative JOA score in group B (p<0.05), age, preoperative JOA score, signal change on T2WI MRI, compression ratio in group C (p<0.05) were significant prognostic factors that influenced the recovery rate. CONCLUSION: There was no difference between the preoperative clinical symptoms and the surgical outcome according to the cause. The most significant prognostic factors affecting the results of surgery for cervical myelopathy were age, preoperative JOA score in each group. A specific prognostic factor in each group may exist, but a further evaluation is needed.


Subject(s)
Humans , Diskectomy , Magnetic Resonance Imaging , Retrospective Studies , Spinal Cord Diseases
14.
Journal of Korean Foot and Ankle Society ; : 267-270, 2006.
Article in Korean | WPRIM | ID: wpr-170836

ABSTRACT

Os trigonum syndrome is a clinical disorder characterized by posterior ankle pain which occurs in excessive plantar flexion. The pain is elicited by the impingement of os trigonum between the calcaneus and the posterior edge of tibial plafond. Mostly, symptoms can be improved with nonsurgical management, however surgery is required for refractory cases. We report of a case of os trigonum syndrome in a female ballet dancer, which was successfully treated with subtalar arthroscopic excision of os trigonum.


Subject(s)
Female , Humans , Ankle , Arthroscopy , Calcaneus , Talus
15.
Journal of the Korean Radiological Society ; : 515-523, 2006.
Article in Korean | WPRIM | ID: wpr-83222

ABSTRACT

PURPOSE: We wanted to evaluate the findings of ferucarbotran-enhanced MR imaging of the radiofrequency (RF) ablation zones in normal rabbit livers and we compared the findings with the conventional MR imaging. MATERIALS AND METHODS: RF ablation zones were created in the livers of 12 rabbits in vivo by using a 17-gauge internally cooled electrode with 1-cm active tip, and RF energy (maximum power: 30 Watt) was applied for three minutes. Three rabbits were sacrificed immediately and then at three days, two weeks and six weeks after RF ablation. Before sacrifice, the T1- and T2-weighted images (WI) and the ferucarbotran-enhanced T2*WIs were obtained and compared regarding the signal intensity of ablation zone, the laminar pattern of the signal intensity and the contrast-to-noise ratio (CNR) of the ablation zone to the liver parenchyma. RESULTS: On T1- and T2WIs, the RF ablation zones showed two to four laminar patterns of signal intensity according to the time. Meanwhile, on the ferucarbotran-enhanced T2WIs, the RF ablation zones showed high signal intensity without a laminar pattern regardless of time. The CNRs of the ablation zones to the liver parenchyma on the ferucarbotran-enhanced T2*WIs (18.2+/-5.9) were significantly higher than those of the TIWIs (1.6+/-1.5) and T2WIs (2.7+/-1.9) (p < 0.05). CONCLUSION: On the ferucarbotran-enhanced T2*WI, the RF ablation zones showed high signal intensity without a distinct laminar pattern and significantly higher lesion conspicuity than did the conventional T1- and T2WIs. Therefore, the ferucarbotran-enhanced T2*WI shows the RF ablation zone more accurately and clearly than do the conventional T1- and T2WIs.


Subject(s)
Rabbits , Catheter Ablation , Electrodes , Liver , Magnetic Resonance Imaging
16.
Korean Journal of Radiology ; : 240-249, 2004.
Article in English | WPRIM | ID: wpr-45951

ABSTRACT

OBJECTIVE: We wished to evaluate the effect of the Pringle maneuver (occlusion of both the hepatic artery and portal vein) on the pathologic changes in the hepatic vessels, bile ducts and liver parenchyma surrounding the ablation zone in rabbit livers. MATERIALS AND METHODS: Radiofrequency (RF) ablation zones were created in the livers of 24 rabbits in vivo by using a 50-W, 480-kHz monopolar RF generator and a 15-gauge expandable electrode with four sharp prongs for 7 mins. The tips of the electrodes were placed in the liver parenchyma near the porta hepatis with the distal 1 cm of their prongs deployed. Radiofrequency ablation was performed in the groups with (n=12 rabbits) and without (n=12 rabbits) the Pringle maneuver. Three animals of each group were sacrificed immediately, three days (the acute phase), seven days (the early subacute phase) and two weeks (the late subacute phase) after RF ablation. The ablation zones were excised and serial pathologic changes in the hepatic vessels, bile ducts and liver parenchyma surrounding the ablation zone were evaluated. RESULTS: With the Pringle maneuver, portal vein thrombosis was found in three cases (in the immediate [n=2] and acute phase [n=1]), bile duct dilatation adjacent to the ablation zone was found in one case (in the late subacute phase [n=1]), infarction adjacent to the ablation zone was found in three cases (in the early subacute [n=2] and late subacute [n=1] phases). None of the above changes was found in the livers ablated without the Pringle maneuver. On the microscopic findings, centrilobular congestion, sinusoidal congestion, sinusoidal platelet and neutrophilic adhesion, and hepatocyte vacuolar and ballooning changes in liver ablated with Pringle maneuver showed more significant changes than in those livers ablated without the Pringle maneuver (p < 0.05) CONCLUSION: Radiofrequency ablation with the Pringle maneuver created more severe pathologic changes in the portal vein, bile ducts and liver parenchyma surrounding the ablation zone compared with RF ablation without the Pringle maneuver. Therefore, we suggest that RF ablation with the Pringle maneuver should be performed with great caution in order to avoid unwanted thermal injury.


Subject(s)
Animals , Male , Rabbits , Bile Ducts/pathology , Catheter Ablation , Disease Models, Animal , Hepatic Artery/pathology , Liver/blood supply , Necrosis , Portal Vein/pathology
17.
Korean Journal of Radiology ; : 185-198, 2004.
Article in English | WPRIM | ID: wpr-68893

ABSTRACT

The early assessment of the therapeutic response after percutaneous radiofrequency (RF) ablation is important, in order to correctly decide whether further treatment is necessary. The residual unablated tumor is usually depicted on contrast-enhanced multiphase helical computed tomography (CT) as a focal enhancing structure during the arterial and portal venous phases. Contrast-enhanced color Doppler and power Doppler ultrasonography (US) have also been used to detect residual tumors. Contrast-enhanced gray-scale US, using a harmonic technology which has recently been introduced, allows for the detection of residual tumors after ablation, without any of the blooming or motion artifacts usually seen on contrast-enhanced color or power Doppler US. Based on our experience and reports in the literature, we consider that contrast-enhanced gray-scale harmonic US constitutes a reliable alternative to contrast-enhanced multiphase CT for the early evaluation of the therapeutic response to RF ablation for liver cancer. This technique was also useful in targeting any residual unablated tumors encountered during additional ablation.


Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Carcinoma, Hepatocellular/diagnostic imaging , Catheter Ablation , Contrast Media , Liver Neoplasms/diagnostic imaging , Polysaccharides , Suspensions , Tomography, Spiral Computed , Ultrasonography, Doppler/methods
18.
Korean Journal of Radiology ; : 117-123, 2003.
Article in English | WPRIM | ID: wpr-229494

ABSTRACT

OBJECTIVE: To assess the sizes and configurations of thermal zones after overlapping ablations using a coaxial radiofrequency (RF) electrode and multiple cannulae in ex-vivo bovine liver. MATERIALS AND METHODS: For ablation procedures, a coaxial RF electrode and introducer set was used. Employing real-time ultrasound guidance and overlapping techniques in explanted, fresh bovine liver, we created five kinds of thermal zones with one (n=10), two (n=8), four (n=3), and six ablation spheres (n=3). Following ablation, MR images were obtained and the dimensions of all thermal zones were measured on the longitudinal or transverse section of specimens. The shape of the composite ablation zones was evaluated using three-dimensional MR image reconstruction. RESULTS: At gross pathologic examination of ten single-ablation zones (spheres), the long-axis (transverse) and short-axis lengths of zones ranged from 3.7 to 4.4 (mean, 4.1) cm and from 3.5 to 4.0 (mean, 3.7) cm, respectively. The long-axis (transverse) and short-axis lengths of double-ablation zones (cylinders) with 23% overlap ranged from 7.0 to 7.7 (mean, 7.3) cm and from 3.0 to 3.9 (mean, 3.5) cm, respectively; those with 58% overlap ranged from 6.0 to 6.4 (mean, 6.2) cm and from 3.8 to 4.6 (mean, 4.3) cm, respectively. The long-axis (diagonal) and short-axis lengths on a transverse section of four-ablation zones (cakes) ranged from 8.5 to 9.7 (mean, 9.1) cm and from 3.0 to 4.1 (mean, 3.7) cm, respectively. Gross pathologic examination of three composite six-ablation zones (spheres) showed that the long-axis (diagonal) and short-axis lengths of zones ranged from 9.0 to 9.9 (mean, 9.4) cm and from 6.8 to 7.5 (mean, 7.2) cm, respectively. T2-weighted MR images depicted low-signal thermal zones containing multiple curvilinear and spotty regions of hyperintensity. CONCLUSION: Using a coaxial RF electrode and multiple cannulae, together with ultrasound guidance and precise overlapping ablation techniques, we successfully created predictable thermal zones in ex-vivo bovine liver.

19.
Journal of the Korean Radiological Society ; : 427-432, 2003.
Article in Korean | WPRIM | ID: wpr-124396

ABSTRACT

PURPOSE: To assess the usefulness of STIR (short tau inversion recovery) imaging in breast MRI (magnetic resonance imaging). MATERIALS AND METHODS: We retrospectively reviewed T1- and T2-weighted (T1WI, T2WI), STIR, and dynamically enhanced images of 44 pathologically confirmed breast lesions (benign, 13; malignant, 31) in 36 patients. We selected the dynamically image which best depicted a particular lesion, and then made hard copy of the corresponding T1WI, T2WI, and STIR images. Using the dynamically enhanced image as a standard, we analysed these in terms of parenchymal pattern, lesion detectability, differentiation between benign and malignant lesions, extent, multifocality, and the ductal system. The results were statistically analyzed. RESULTS: In 33 of 44 cases (75%), detectability was greater at STIR imaging than at T1- and T2WI, especially in fibrofatty or fatty breast (14/14 cases, p<0.05). STIR images did not always differentiate between benign and malignant lesions, and extent (50%) and multifocality (46%) were commonly exaggerated compared with T1- and T2WI. In 18 of 44 cases (41%), STIR images suggested the presence of ductal structures. CONCLUSION: For the detection of lesions, STIR imaging was more useful than T1- and T2WI, though STIR did not differentiate between benign and malignant lesions. The extent and multifocality of a lesion were exaggerated on STIR images, compared with T1- and T2WI.


Subject(s)
Humans , Breast , Magnetic Resonance Imaging , Retrospective Studies
20.
Journal of the Korean Radiological Society ; : 319-326, 2003.
Article in Korean | WPRIM | ID: wpr-114455

ABSTRACT

PURPOSE: To evaluate the usefulness and the application of three dimensional digital rotational imaging (3D DRI) by the evaluation of fractures. MATERIALS AND METHODS: Sixteen patients with clinically diagnosed or suspicious fracture were involved in this study. The lesion or suspicious sites of all 16 cases were spines (n=7), pelvis (n=3) and so on (n=6; knee, elbow, ankle, wrist and foot). In all cases, conventional radiography, multiplanar 2D (slice thickness/pitch=3 or 5 mm/1:1)and volume rendering 3D reconstructed single detector helical CT (HiSpeed Advantage, GE Medical Systems, Milwaukee, WIS) scans and 3D DRI (Integris V-5000,Philips Medical Systems, The Netherlands) with multiplanar intersection and gray scaling as postprocessing technique were performed. 3D DRI was evaluated and compared with conventional radiography, multiplanar 2D CT and volume rendering 3D CT. RESULTS: 3D DRI provided more detail and additional information in 14 cases (88%), comparing with 2D and 3D CT scans. Two fractures were revealed only on 3D DRI other than conventional radiography and CT scans and one case was revealed on 2D CT and 3D DRI. In all cases, we could acquired more detail and additional information from 3D DRI than from 3D CT in the acquisition of 3D imaging. 3D DRI didn't change the classification of fracture in 12 of 13 cases (92%),which revealed the fracture on the conventional radiography or CT. CONCLUSION: 3D DRI can diagnose and evaluate the fracture rapidly and easily with anatomical and spatial resolution by acquisition of 3D imaging with postprocessing using DRI.


Subject(s)
Humans , Ankle , Classification , Elbow , Imaging, Three-Dimensional , Knee , Pelvis , Radiography , Spine , Tomography, Spiral Computed , Tomography, X-Ray Computed , Wrist
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