Comparison of Brain Activation in Response to Two Dimensional and Three Dimensional On-Line Games

OBJECTIVE: The present study assessed the difference in the brain activity of professional gamers (excessive players, but not addicts) in response to playing a 3-dimensional online game with an improved interface. METHODS: Twenty-three StarCraft I pro gamers and 16 StarCraft II pro gamers were recruited at Chung Ang University Medical Center. Brain activity in response to StarCraft I or II cues was assessed with a 1.5 Tesla Espree MRI scanner. RESULTS: StarCraft I pro gamers showed significantly greater activity in 4 clusters in response to the video game cues compared to StarCraft II pro gamers: right superior frontal gyrus, right medial frontal gyrus, right occipital lobe, and left medial frontal gyrus. StarCraft II pro gamers showed significantly greater activity in 3 clusters in response to the video game cues compared to StarCraft I pro gamers: left middle frontal gyrus, left temporal fusiform gyrus and left cerebellum. DISCUSSION: This is the first study to show the difference in brain activity between gamers playing either a 2-dimensional or 3-dimensional online game. Current brain imaging studies may confirm the pro gamers' experience when playing StarCraft II, a 3-dimensional game with an improved interface, relative to playing StarCraft I.

In vivo Tracking of Mesenchymal Stem Cells Labeled with a Novel Chitosan-coated Superparamagnetic Iron Oxide Nanoparticles using 3.0T MRI

This study aimed to characterize and MRI track the mesenchymal stem cells labeled with chitosan-coated superparamagnetic iron oxide (Chitosan-SPIO). Chitosan-SPIO was synthesized from a mixture of FeCl2 and FeCl3. The human bone marrow derived mesenchymal stem cells (hBM-MSC) were labeled with 50 microg Fe/mL chitosan-SPIO and Resovist. The labeling efficiency was assessed by iron content, Prussian blue staining, electron microscopy and in vitro MR imaging. The labeled cells were also analyzed for cytotoxicity, phenotype and differentiation potential. Electron microscopic observations and Prussian blue staining revealed 100% of cells were labeled with iron particles. MR imaging was able to detect the labeled MSC successfully. Chitosan-SPIO did not show any cytotoxicity up to 200 microgram Fe/mL concentration. The labeled stem cells did not exhibit any significant alterations in the surface markers expression or adipo/osteo/chondrogenic differentiation potential when compared to unlabeled control cells. After contralateral injection into rabbit ischemic brain, the iron labeled stem cells were tracked by periodical in vivo MR images. The migration of cells was also confirmed by histological studies. The novel chitosan-SPIO enables to label and track MSC for in vivo MRI without cellular alteration.

Endovascular Treatment for Common Iliac Artery Injury Complicating Lumbar Disc Surgery : Limited Usefulness of Temporary Balloon Occlusion

Vascular injury during lumbar disc surgery is a rare but potentially life-threatening complication. It has been managed by open vascular surgical repair. With recent technologic advance, endovascular treatment became one of effective treatment modalities. We present a case of a 32-year-old woman who suffered with common iliac artery injury during lumbar disc surgery that was treated successfully by endovascular repair with temporary balloon occlusion and subsequent insertion of a covered stent. Temporary balloon occlusion for 1.5 hours could stop bleeding, but growing pseudoaneurysm was identified at the injury site during the following 13 days. It seems that the temporary balloon occlusion can stall bleeding from arterial injury for considerable time duration, but cannot be a single treatment modality and requires subsequent insertion of a covered stent.

Comparison of the CT and Pathologic Findings of Pulmonary Fat Embolism Induced by Triolein and Oleic Acid in Rabbits

PURPOSE: The aim of this study was to evaluate the CT findings of pulmonary fat embolism syndrome that was induced by triolein and oleic acid, along with its pathologic correlation. MATERIALS AND METHODS: 16 rabbits were included in this study. The rabbits in group I (n=8) were embolized with 0.2 mL triolein and the rabbits of group II (n=8) were embolized with 0.2 mL oleic acid through ear veins. HRCT scans were done prior to embolization and at 0.5, 4, 24, 48 and 72 hours post-embolization. The pathologic correlations were determined at 0.5, 24, 48 and 72 hours. RESULTS: At 24 hours, one group I rabbit showed abnormal CT findings that were composed of several 2-3 mm nodules and multiple ill-defined peripheral ground glass opacities. The pathologic finding of this rabbit at 48 hours was mainly intraarveolar edema. All the group II rabbits (n=8/8) showed ill-defined bilateral and peripheral ground glass opacities with (n=6/8) or without consolidations (n=2/8) on the 0.5 hour CT. All the rabbits (n=7/7) showed that the new ground glass opacities and ground glass opacities noted on the 0.5 hour CT were changed into consolidation. The margins of the ground glass opacities and consolidations were more sharpened on the 24 hours CT. All 6 rabbits (n=6/6) showed consolidations without ground glass opacities and the margins of the consolidations were more sharpened on the 48 hours CT. There was no significant interval change on the 72 hours CT. The pathologic findings of ground glass opacities were interstitial edema or mild intraalveolar edema. The pathologic findings of consolidation were intraalveolar edema, hemorrhage and coagulation necrosis. CONCLUSION: The CT findings after fat embolization using triolein and oleic acid were ill-defined peripheral ground glass opacities with/without consolidations. These findings occurred in only one triolein group with the time lag, but these findings were immediately and extensively seen in all group II rabbits. These CT findings may be important for making a diagnosis of pulmonary fat embolism syndrome.

Ultrasound-Guided Radiofrequency Ablation of Thyroid Gland: A Preliminary Study in Dogs

PURPOSE: The purpose of this study was to evaluate the possibility of using radiofrequency ablation as the treatment modality for the benign or malignant thyroid nodules in humans. Therefore, we examined the results of using radiofrequency ablation on the thyroid glands in dogs, in respect of the extent of the ablated tissue and the complications. MATERIALS AND METHODS: Five dogs (10 lobes of the thyroid glands) were included in this study. US-guided radiofrequency ablation was undertaken with a 10mm, uncovered 17 gauge cool-tip needle. The power and duration was 20 wattage and 1 minute in five thyroid lobes (group 1) and 20 wattage and 2 minutes in another 5 thyroid lobes (group 2). The ultrasound scans and the pre-and post-enhancement CT scans were undertaken before and immediately after the procedures, and at 24 hours, 72 hours and 1 week later. The US and CT findings of the ablated tissue and complications were evaluated. Blood sampling was done at the pre-procedure time and 1 week later for evaluating the functional status of the thyroid gland. Laryngoscopy was done at the pre-procedure and post-procedure times, and at 24 hours, 72 hours and 1 week later for the evaluation of any recurrent laryngeal nerve palsy. RESULTS: The echo pattern of the ablated thyroid gland at immediately after the radiofrequency ablation appeared as poorly marginated and hyperechoic. On the US obtained 24 hours after radiofrequency ablation, the echo pattern of the ablated thyroid gland was hypoechoic. The maximum diameters after RFA were 9.4+/-0.5 mm in group I and 11.4+/-0.5 mm in group II. The pre-enhanced CT scan taken at immediately after the radiofrequency ablation showed ill defined hypodense areas in the ablated thyroid gland. Differentiation between the normal and abnormal portions of the thyroid gland was difficult on the contrast enhanced CT scan. Complications induced by radiofrequency ablation were one recurrent laryngeal nerve palsy, two perforations of esophagus and five thickenings of the esophageal wall. In summary, the radiofrequency ablation therapy for the benign or malignant thyroid nodules located in anterior aspect (within a 5 mm radius) of the thyroid gland in human suggests this is an effective treatment, through this was an animal study performed on dogs.

One case of intraosseous ganglion

Intraosseous ganglion is a rare disease and identified as a cystic lesion on plain radiograph. One case ofintraosseous ganglion is examined by plain radiography and CT and findings are analyzed.

Radiological diagnosis of perinephric abscess

With conventional radiological approaches, diagnosis of perinephric abscess is difficult in many occasions. CTand ultrasound enable accurate detection of lesions and precise determination of their extent. We review our casesand discuss the usefulness of these new modalities for the diagnosis and follow up of the lesions.

Normal and variations of internal pudendal artery in penilearteriography

No abstract available.

A Clinical Review and Comparative Study of CBD Exploration and Percutaneous Transhepatic Stone Removal for Management in Recurrent Biliary Stone

PURPOSE: Recurrent bile duct stones, following biliary surgery, cause many difficult problems and reoperation on the biliary tract has limitation due to high mortality and morbidity. In recent years, various non-operative modalities for the management of recurrent stone have been developed and reoperation on biliary. This study was designed to determine the factors contributing to the success rate, and to investigate the optimal treatment method, of reccurrent biliary stones. METHODS: Thirty-nine patients, treated by percutaneous transhepatic stone removal (PTBD group), and 42 treated by a common bile duct exploration (operation group), at Chung- Ang University Hospital, between January 1999 and August 2002, were retrospectively analyzed. RESULTS: Complete removal (Success) was achieved in 82.1 and 86.1% of the cases of the PTBD and operation groups, respectively. There were no significant differences observed relating to the sex, age, duration of hospital stay, cost, success rate. However, the complication rate was significantly decreased in the PTBD group (8 cases (20.5%) vs. 22 cases (51.2%) P=0.0057). CONCLUSION: Form the comparison of the operation and PTBD groups, similar success rates were observed. Percutaneous transhepatic stone removal is also an effective method for the management of recurrent bile duct stones. After studying more cases, re-evaluation must be performed concerning the potential advantages of percutaneous transhepatic stone removal.

Superselective embolization of brain arteriovenous malformations using microcatheter: Evaluation of success rate and complications

Recently, accumulation of knowledge on cerebrovascular microanatomy and its hemodynamics and advances in interventional equipments, especially microcatheters, could make superselective embolization as well as for an adjunctive preoperative procedures The authors performed superselective angiography and embolization with Tracker microcatheter in 25 procedures out of 15 patients with brain arteriovenous malformations (AVMs). Complete embolization was done in 7 prtients (46.7%), nearly complete embolization in 6 patients(40.4%), and partial embolization in 2 patients (13.3%). The overall curative success rate of embolization was 86.7%. Five patients showed no complication at all. Mild complications, however, were observed in 7 patients (46.8%). Severe complications such as AVM or Tracker rupture were observed in 3 patients (20%). In conclusion, superselective embolization is and effective method for the treatment of brain AVMs, and multiple session embolizations could reduce the complication rate and increase the success rate.

Incidental gallbladder opacification after intravascular contrast infusion

Opacification of the gallbladder after parenteral administration of contrast material usually indicates diminished renal function but can occur with normal renal function. The authors recently experienced 13 cases of such vicarious excretion of contrast media. Among 13 patients. 9 patients had renal disease unilateral ureteral stone(n=3), staghorn calculi(n=2), acute renal failure from sepsis(n=1), renal contusion(n=2) and unilateral renal artery involvement by dissecting aortic aneurysm(n=1). Of these 9 patients, 3 patients showed abnormal serum creatinine levels at the time of presentation or shortly thereafter. In 6 patients, injection of a large amount of contrast media was possibly the additional cause of vicarius excretion. There was no detectable cause in the remaining 4 patients. Heterotopic excretion of contrast media is clearly a complex phenomenon, the reason for which it is difficult to establish with certainty in each individual case. Anyhow, vicarius excretion of contrast media occurs more frequently than previously thought, and it can occur not only with abnormal renal function but with normal function also.

Fixation Methods for Implantable Port Chamber: Comparative Study Using Glue, Self-stabilizing Leg and Suture Fixations in Rabbits

OBJECTIVE: To evaluate the fixation strength and tissue reaction of the glue fixation and self-stabilizing leg fixation methods and to compare the results with those of the conventional tagging suture fixation method. MATER AND METHODS: Twelve healthy rabbits were selected and three different methods of implanting the port chamber were employed on the back of each rabbit. A total of thirty six port chambers were implanted with these three different methods, viz. the glue fixation method using tissue adhesive, the self-stabilizing leg method using a self-expandable stabilizing leg, and the suture fixation method. The fixation strength and the gross and histopathologic changes of each fixation method were evaluated at three days, one week, two weeks and four weeks after port implantation. RESULTS: The glue fixation method showed a good fixation strength, which was similar to that of the tagging suture method (p=0.3486). Five of the six ports (83%) implanted with the glue fixation method which were examined after two weeks showed cracks on the external surface, but this had no adverse effects on their function. A large amount of granulation tissue reaction was found at the bottom of the chamber (p=0.0025). The fixation with the self-stabilizing leg showed relatively lower fixation strength (p=0.0043), but no turning-over of the chamber occurred. The fixation strength improved with time after the first week, and minimal granulation tissue reaction was observed with this method. CONCLUSION: The glue fixation method exhibited equal fixation strength compared to the suture fixation, but showed cracking and a large amount of granulation tissue, whereas the fixation with a self-stabilizing leg showed weaker fixation strength.

Evaluation of clot formation in blood-contrast agent mixture: experimental study on ionic/nonionic contrast agents and plastic/ glass syringes

No abstract available.

Post-traumatic Arterial Priapism: Doppler Ultrasonographic Findings and Therapeutic Embolization

Two cases of post-traumatic arterial priapism diagnosed with duplex and color Doppler ultrasonography showed pseudoaneurysm and increased peak systolic and diastolic velocity of the inflowing cavernosal artery(low resistance index). An autologous blood clot successfully controlled tumescence and was comfortable and secure in preventing necrosis and impotence.

A Study on Early Microstructural Changes in the Rabbit Gallbladder Induced by Shock Waves

PURPOSE: In order to evaluate microstructural changes after shock wave exposure, gross, light microscopic and transmission electron microscopic findings were analyzed with rabbit gallgladders. MATERIALS AND METHODS: A preliminary study(2 rabbits) was performed to determine the dosage intensity of shock waves needed to inflict damage, using a EDAP LT 01 piezoelectric extracorporeal shock wave Iothotriptor. The gallbladders of three different groups of rabbits were given shock waves of various intensity. A storage value of 100, 50, 25 at rate of 20/sec under 80% power were given to group I (4 rabbits), group II( 4 rabbits), and group III(3 tabits), respectively. The rabbits were sacrified 6--12 hours later. RESULTS: The observed pathologic changes in the transmission electron microscopy were vaculization of cytoplasm and swelling of epithelial cells with dilatation and structural alteration of intracellular organelles, especially endoplasmic reticulum. Cell membrane rupture and necrosis were observed at the markedly affected area. The structural changes of intracellular organelles were minimally found at a storage value of 25. However, above pathologeic changes with dilatation and structural alterations of endoplasmic reticulums were more profund at value of 100. CONCLUSION: Early histologic changes induced by shock waves are dose dependent and the findings of cellular damage caused by ESWL might be explained as above.

Change in Pancreatic Size after Gastric Resection: CT Evaluation

PURPOSE:The purpose of this study is to evaluate the change of pancreatic size after gastric resection in patients with gastric malignancy. MATERIALS AND METHODS: We compared the pancreatic sizes on pre- and post-operative abdominal CT scans in 50 patients whose stomach had been resected due to malignancy. The mean interval was 20.3 months (range, 5-81 months). The types of the operation were total gastrectomy with esophagojejunostomy and jejunojejunostomy (n=7), and subtotal gastrectomy with gastrojejunostomy (Billroth II) (n=43). Pancreatic thickness was measured perpendicular to the pancreatic long axis at head, body and tail. RESULT: There was a significant reduction of pancreatic size on postoperative CT scan. The reduction rate was 5.9% in the head (p<0.001), 7.1% in the body (p<0.001) and 14.4% in the tail (p<0.001). CONCLUSION:Significant reduction of pancreatic size was observed after gastric resection due to gastric rnalignancy, especially in tail.

Correlation of VEGF with contrast enhancement on dual-phase dynamic helical CT in liver tumors: preliminary study

The purpose of this preliminary study is to elucidate that vascular endothelial growth factor (VEGF) influences contrast enhancement of hepatic tumors on computed tomography (CT). Fourteen patients with hepatic tumors (11 hepatocellular carcinomas; 3 metastatic cancers) underwent a dual-phase dynamic helical CT or computed tomographic hepatic arteriography. The attenuation of each mass was determined as hyperattenuation, isoattenuation or hypoattenuation with respect to the adjacent nontumorous parenchyma. Gun-needle biopsy was done for each tumor, and paraffin sections were immunostained with anti- VEGF antibody by the avidin-biotin-peroxidase complex method. The pathologic grade was made by intensity (1 +, 2+, 3+) and area (+/-, 1 +, 2+). The tumor ranged 2.0-14.0 cm in size (mean, 5.8 cm). In arterial phase, the intensity was not correlated with the degree of enhancement (p=0.086). However, the correlation between the attenuation value of hepatic arterial phase and the area of positive tumor cells was statistically significant (p=0.002). VEGF may be the factor that enhances the hepatic mass with water-soluble iodinated contrast agent in CT.

Percutaneous Removal of the Retained Biliary Stones: Evaluation of the Results on of Impatient-basis Management

PURPOSE: All procedures for the removal of retained intrahepatic stones were performed on inpatient basis. We evaluated the advantage of the procedures performed on inpatient basis compared with outpatient basis in terms of the success rate, causes of failure and the complication. MATERIALS AND METHODS: Percutaneous removal of retained intrahepatic stones was performed in 58 patients through a T-tube tract on inpatient basis from April 1990 to December 4992. Stones were exclusively intrahepatic in 28 patients, whereas 30 patients had combined stones in common bile duct. Preshaped catheters, baskets, and balloon catheters were used to remove the stones and dilate the strictures of the ducts. Extracorporeal shock wave lithotripsy and choledochoscopy with electrohydraulic lithotripsy were used to crush the impacted stones. RESULTS: The stones were completely removed in 34 (58.6%) of 58 patients and most of the stones were removed in 17 patients (29.3%). The overall success rate was 87.9%. The complications (cholangitis in 13% and pancreatitis in 0.8% per session) were found and successfully managed by appropriate care. CONCLUSION: Better success rate could be achieved by more aggressive appraoch on inpatient basis when compared with previous reports on outpatient basis. We suggest that the procedures should be performed on inpatient basis especially in a case with severe strictures or impacted stones.

Effect of Transcatheter Arterial Embolization according to Angiographic Findings in Hepatocellular Carcinoma

PURPOSE: The purpose of this study is to assess the effect of Transcatheter Arterial Embolization(TAE) according to anglographic findings in hepatocellular carcinoma. MATERIALS AND METHOD: We retrospectively reviewed 50 cases who received TAE for unresectable hepatocellular carcinoma. We analyzed the anglographic findings which were correlated with the effect of TAE. The common anglographic findings of the hepatocellular carcinoma were tumor staining, neovascularity and enlargement of feeding artery. These anglographic findings were classified into grade 0, +1, +2. Effect of TAE were classified into five patterns;good response, partial response, minimal response, no response and more aggravation. RESULT:In grading of tumor staining, among 50 cases, the grade 0, +1, +2 were seen in 1 case(2%), 14 cases(28%), 35 cases(70%) each. In grading of enlargement of feeding artery, the grade 0, +1, +2 were seen in 7 cases(14%), 19 cases(38%), 24 cases(48%) each. In grading of neovascularity, the grade 0, +1, +2 were seen in 6 cases(12%), 15 cases(30%), 29 cases(58%) each. This study showed that the higher grade of anglographic finding, the better effect of TAE. A statistically significant differance was found (p<0.005). But the TAE was not effective in some cases (the maximum diameter of mass is over 10cm, portal vein thrombosis or ateriovenous shunt) in spite of high grade. CONCLUSION: We believe that these angiogr. aphic findings (tumor staining, enlargement of feeding artery, neovascularity) are one of important indices for anticipating the effect of TAE in patients with unresectable hepatocellular carcinoma.

Gallbladder contractability before and after extracorporeal shock- wave lithotripsy

No abstract available.