Cavernous Hemangioma of the Ilium Mimicking Aggressive Malignant Bone Tumor with Increased Activity on 18F-FDG PET/CT

Osseous hemangioma is a benign vascular tumor, and it usually occurs in the vertebrae and the skull. However, hemangiomas of flat bones are rare, and there are very few reports that describe the radiologic findings of osseous hemangioma of the ilium. We report a unique case of large cavernous hemangioma mimicking a chondrogenic malignant bone tumor originated from the ilium in a 22-year-old female. The mass showed stippled calcifications, heterogeneous enhancement with thick septa and enhanced soft tissue components on CT and MR, and also this mass demonstrated heterogeneous 2-fluoro [fluorine-18]-2-deoxy-D-glucose (18F-FDG) uptake on 18F-FDG PET/CT.

Underestimation of Ductal Carcinoma In situ on Sonographically Guided Core Needle Biopsy of the Breast

PURPOSE: The purpose of this study was to determine the underestimation rate of ductal carcinoma in situ (DCIS) on sonographically guided 14-gauge core needle biopsy of the breast and to investigate the factors associated with this underestimation. MATERIALS AND METHODS: We retrospectively reviewed 2990 consecutive lesions that underwent sonographically guided 14-gauge core needle biopsy between January 2005 and December 2008. Among them, 61 lesions were pathologically proven to be DCIS (2.04%). A total of 50 DCIS lesions (mean patient age: 50.7 years old, age range: 36-79 years old) that underwent surgical resection were included in this study. After surgery, the lesion proven to be invasive was defined as being in the underestimated group and the lesion proven to DCIS was defined as being in the correctly diagnosed group. We determined the underestimation rate of DCIS and we retrospectively reviewed and compared the clinical, pathologic and radiologic features of the two groups. RESULTS: The underestimation rate of DCIS was found to be 28% (14 of 50 lesions). The underestimation of DCIS was significantly frequent for a clinically palpable lesion (78.6% (11/14) vs. 30.5% (11/36), respectively, p = 0.002). The sonographically maximal diameter of a lesion was significantly larger in the underestimated group than that in the accurately diagnosed group (28.4 +/- 14.0 mm vs. 17.6 +/- 10.3 mm, respectively, p = 0.017) and underestimation was significantly frequent when the sonographic lesion size was > 20 mm (p = 0.012). There was no significant difference in terms of age, the lesion type, the Breast Imaging-Reporting and Data System (BI-RADS) category or the pathologic features between the two groups. CONCLUSION: The underestimation rate of DCIS was 28% for sonographically guided 14-gauge core needle biopsy of the breast. Clinical symptoms such as a palpable lesion and a sonographic lesion size > 20 mm were the factors related with the underestimation of DCIS.

Intramuscular Ganglion Cyst of the Gastrocnemius Muscle / 대한피부과학회지

Ganglion cysts are common lesions that are most often found around the hands and feet. Ganglia around the proximal tibiofibular joint usually occur within the synovial membrane, tendon sheath or peroneal nerve, but they rarely occur within muscle. We report here on a case of a 60-year-old man who complained of an asymptomatic deep seated mass in the proximal part of the right calf that he'd had for more than two years. On magnetic resonance imaging, the lesion appeared as a cystic lesion within the gastrocnemius muscle without communication with the knee joint. To the best of our knowledge, intramuscular ganglion cyst has never been reported in the Korean dermatologic literature.

Molecular MR Imaging for Visualizing ICAM-1 Expression in the Inflamed Synovium of Collagen-Induced Arthritic Mice

OBJECTIVE: To determine the utility of intercellular adhesion molecule (ICAM)-1 antibody-conjugated gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA-anti-ICAM-1) as a targeted contrast agent for the molecular magnetic resonance imaging (MRI) in collagen-induced arthritis (CIA). MATERIALS AND METHODS: Three groups of mice were used: non-arthritic normal, CIA mice in both the early inflammatory and chronic destructive phases. The MR images of knee joints were obtained before and after injection of Gd-DTPA-anti-ICAM-1, Gd-DTPA, and Gd-DTPA-Immunoglobulin G (Ig G) and were analyzed quantitatively. The patterns of enhancement on the MR images were compared with the histological and immunohistochemical ICAM-1 staining. RESULTS: The images obtained after injection of Gd-DTPA-anti-ICAM-1 displayed gradually increasing signal enhancement from the moment following injection (mean +/- standard deviation [SD]: 424.3 +/- 35.2, n = 3) to 24 hours (532 +/- 11.3), rather than on pre-enhanced images (293 +/- 37.6) in the early inflammatory phase of CIA mice. However, signal enhancement by Gd-DTPA and Gd-DTPA-IgG disappeared after 80 minutes and 24 hours, respectively. In addition, no significant enhancement was seen in the chronic destructive phase of CIA mice, even though they also showed inflammatory changes on T2-weighted MR images. ICAM-1 expression was demonstrated in the endothelium and proliferating synovium of the early inflammatory phase of CIA mice, but not in the chronic destructive phase. CONCLUSION: Molecular MRI with Gd-DTPA-anti-ICAM-1 displays specific images targeted to ICAM-1 that is expressed in the inflamed synovium of CIA. This novel tool may be useful for the early diagnosis and differentiation of the various stages of rheumatoid arthritis.

Metastatic Osteosarcoma to the Prostate: A Case Report

The most common site for the metastasis of osteosarcoma is the lung, and other sites of metastases include the bone, lymph node, pleura and liver. Although unusual extrapulmonary metastases have been reported with the improvement of the therapeutic results for the primary lesions, they are exceptionally rare. We report here on a case of prostatic metastasis of an osteosarcoma of the proximal tibia, and this developed seven years after successful resection, and four years after resection of a pulmonary metastasis. Radical prostatectomy was performed, and histological examination demonstrated metastatic osteosarcoma. To the best of our knowledge, this is the first case of prostatic metastasis of osteosarcoma in the medical literature.

Erratum

No abstract available.

CT-guided Transthoracic Needle Biopsy with an 18-Guage Automated Cutting Needle: Diagnostic benefits and safety

PURPOSE: We wanted to evaluate the diagnostic benefits and safety of performing CT-guided transthoracic needle biopsy (TTNB) with using an18-gauge automated cutting needle. MATERIALS AND METHODS: We retrospectively reviewed the medical records of 332 patients who underwent CT-guided transthoracic biopsy with an automated 18-gauge cutting needle for 341 thoracic lesions. The histopathologic results, diagnostic accuracy and complication rate were determined. RESULTS: 316 (92.7%) of 34l lesions were histopathologically diagnosed by CT-guided TTNB. The lesions were malignant in 172 patients and benign in 144 patients. The diagnostic accuracy was 92.9%. The sensitivity and specificity for malignant lesions were 93% and 92.3%, respectively. The sensitivity and specificity for benign lesions were 92.3% and 93%, respectively. TTNB induced complications developed for 54 of 341 (15.8%) procedures. The most frequent complication was pneumothorax (41/341, 12%). Nine patients with pneumothorax (9/41, 22%) required chest tube placement. CONCLUSION: CT-guided TTNB with an 18-gauge automated cutting needle could be useful for making the histopathologic diagnosis of malignant and benign pulmonary lesions as the technique provides a big enough tissue sample for histopathologic examination. The procedure-related complication rate was acceptably low.

Superselective Transarterial Embolization for the Management of Acute Gastrointestinal Bleeding

PURPOSE: We wanted to evaluate the safety and effectiveness of superselective transarterial embolization for the management of gastrointestinal bleeding. MATERIALS AND METHODS: We evaluated 97 of 115 patients who had undergone diagnostic angiography and transarterial embolization for gastrointestinal bleeding from February 2001 to July 2004, and they subsequently underwent superselective transarterial embolization. Their ages ranged from 17 to 88 years (mean age: 58.5 years), and 73 were men and 24 were women. The etiologies were a postoperative condition (n=31), ulcer (n=23), Mallory-Weiss syndrome (n=3), trauma (n=3), pseudoaneurysm from pancreatitis (n=3), diverticula (n=2), inflammatory bowel disease (n=2), tumor (n=2), Behcet's disease (n=2), hemobilia (n=1), and unknown origin (n=25). The regions of bleeding were the esophagus (n=3), stomach and duodenum (n=41), small bowel (n=38) and colon (n=15). All the patients underwent superselective transarterial embolization using microcoils, gelfoam or a combination of microcoils and gelfoam. Technical success was defined as devascularization of targeted vascular lesion or the disappearance of extravasation of the contrast media, as noted on the angiography after embolization. Clinical success was defined as the disappearance of clinical symptoms and the reestablishment of normal cardiovascular hemodynamics after transarterial embolization without any operation or endoscopic management. RESULTS: The technical success rate was 100%. The primary clinical success rate was 67% (65 of 97 patients). Of the 32 primary failures, fourteen patients underwent repeat embolization; of these, clinical success was achieved in all the patients and so the secondary clinical success rate was 81% (79 of 97 patients). Of the 18 patients with primary failures, five patients underwent operation, one patient underwent endoscopic management and the others died during the observation period due to disseminated coagulopathy or complications of their underlying diseases. During the follow up period, six patients of the 79 clinically successful patients died due to disseminated coagulopathy or complications of their underlying diseases, and so the total mortality rate was 19% (18 of 97 patients). Postembolization complications such as bowel ischemia or infarction did not occur during the observation period. CONCLUSION: Superselective transarterial embolization is an effective therapy for treating acute gastrointestinal hemorrhage, and it has a high technical rate and clinical success rate, and a low complication rate.

Malignant Solitary Pulmonary Nodule: Enhancement Patterns on Contrast-enhanced Dynamic CT with the Histopathologic Evaluation

PURPOSE: We wanted to evaluate the potential role of dynamic incremental computed tomography (CT) for making the diagnosis of malignant solitary pulmonary nodule (SPN) by investigating the dynamic enhancement patterns. MATERIALS AND METHODS: Forty patients with presumed malignant SPN (diameter 0.05). CONCLUSION: Dynamic incremental chest CT was useful for making the diagnosis of malignant SPN that showed an established dynamic contrast enhancement pattern regardless of the histopatholgic subtypes.

The Histopathologic Reaction of Rabbit Lungs after Intrabronchial Application of Contrast Agents

PURPOSE: The aim of this study was to determine a safe gastrointestinal contrast agent that could be used in various clinical situations where there is a risk of aspiration using a rabbit model. MATERIALS AND METHODS: 30 healthy white rabbits were used. The rabbits were divided into 5 groups containing six animals each, one control group (anesthesia only) and 4 groups receiving various contrast agents [Solotop (Barium sulphate suspension), Gastrografin (Sodium and meglumine amidotrizoate), and Telebrix (Meglumine ioxitalamate), Visipaque (Iodixanol)]. The contrast agents were injected selectively into a main bronchus via a catheter inserted under fluoroscopy guidance. The rabbits were sacrificed either 1 day or 7 days after injecting the contrast agents, and the tissue reaction of the bronchi and lungs were examined both macro- and microscopically. The level of alveolar septal thickening, peribronchiolar lymphocytic infiltration, pulmonary congestion and edema, inflammatory exudate in the alveoli or bronchiolar lumina, microabscess formation, necrosis, pigmentation of materials injected, and fibropurulent pleurisy were evaluated and graded according to the severity as follows: no change, mild, moderate, marked in degree. RESULTS: The common microscopic findings were alveolar septal thickening and peribronchiolar lymphocytic infiltration. Pulmonary congestion and edema, inflammatory exudate in the alveoli or bronchiolar lumina were observed in 21 out of 24 rabbits receiving the contrast agents. Pigmentation of the materials injected was observed only in the group receiving Solotop. An inflammatory exudate in the alveoli and bronchiolar/bronchial lumina, microabscess formation, and necrosis were noted in most groups, but was more frequent and severe in the group receiving Gastrografin. CONCLUSION: The histopathological reactions of the rabbit lungs after the intrabronchial application of a contrast agent showed variable degrees of inflammatory reactions. Gastrografin produced most severe and extensive reaction, Solotop and Telebrix a moderate reaction, and Visipaque a minimal reaction. Therefore, a non-ionic dimeric contrast agent such as Visipaque may be the safest contrast agent in the lung when a GI tract examination is performed in clinical situations where there is a risk of aspiration.

Metastatic Bone Tumors with Sunburst Periosteal Reaction

PURPOSE: The purpose of this study was to describe the clinical and imaging features of metastatic bone tumors with sunburst periosteal reaction and to define the characteristic findings which would be helpful for differentiating metastatic bone tumors from primary malignant bone tumors. MATERIALS AND METHODS: The authors retrospectively reviewed the cases of nine patients with pathologically confirmed metastatic bone tumors with sunburst periosteal reaction, for which imaging studies (plain radiographs [n=9], radioisotope [RI] scans [n=4], magnetic resonance [MR] images [n=6], and computed tomographic [CT] scans [n=4]) were performed. The imaging studies of each lesion were analyzed by two musculoskeletal radiologists focusing on the metastatic site, patterns of bone response, signal intensity characteristics and pattern of contrast enhancement on MR. The clinical records of the patients were reviewed with regard to the age and sex of the subjects, the clinical presentation, and the origin of the primary tumors. RESULTS: The cases consisted of six men and three women, whose mean age was 62 years (age range, 50-88 years). The primary tumors were adenocarcinoma of the stomach [n=4], adenocarcinoma of the lung [n=2], adenocarcinoma of the prostate [n=1], hepatocellular carcinoma of the liver [n=1], and adenocarcinoma of unknown origin [n=1]. The sites of metastatic involvement exhibiting sunburst periosteal reaction were the scapula [n=2], proximal humerus [n=2], rib [n=1], iliac bone [n=1], tibia [n=1], spine [n=1], and proximal phalanx [n=1]. In all patients, the imaging findings showed osteolytic [n=3] or osteoblastic [n=6] lesions with sunburst periosteal reaction. In six cases, the lesions were iso-intense on the T1-weighted images and heterogeneously hyperintense on the T2-weighted images. The gadolinium-enhanced T1-weighted images showed a nearly homogenous enhancement of the lesions without any central necrotic portion. CONCLUSION: Although metastatic bone tumor exhibiting sunburst periosteal reaction is rare, it should be included along with primary malignant bone tumors in the differential diagnosis of bone lesions with sunburst periosteal reaction, especially in older patients with or without a known primary malignancy.

Hepatic Enhancement on Gd-BOPTA-enhanced MR Imaging: Comparison between Cirrhotic and Normal Livers

PURPOSE: To compare the enhancement features of hepatic parenchyma between cirrhotic and normal liver, using Gd-BOPTA-enhanced delayed MR imaging. MATERIALS AND METHODS: The 60 patients (35 with cirrhotic and 25 with normal liver) included in our study underwent Gd-BOPTA-enhanced MR imaging using a 1.5T system with a phase-array multicoil. In all cases, T1-weighted in-phase and opposed-phase gradient-echo MR imaging was performed before and 60 minutes after intravenous administration of a bolus of Gd-BOPTA. All images were quantitatively analysed by comparing the signal-to-noise ratio (SNR) and signal enhancement (SE) of cirrhotic and normal liver before and after contrast enhancement, and in cirrhotic patients, SNR and SE were also compared in terms of the Child-Pugh classification. For qualitative analysis, the hepatic enhancement patterns of cirrhotic and normal liver were classified as homogeneous or heterogeneous according to the consensual findings of two radiologists. RESULTS: At contrast-enhanced imaging, both cirrhotic (p<0.001) and normal liver (p<0.001) showed substantially increased SNR relative to unenhanced images, and the SNR of cirrhotic liver was significantly lower than that of normal livers at both in-phase (p<0.001) and opposed-phase (p<0.001) imaging. The SE of cirrhotic liver was significantly lower than that of normal liver (in-phase: p=0.002; opposed phase: p=0.011). Both Child-Pugh class A (p<0.001) and B (p<0.001) cirrhotic liver showed a substantial increase in SNR at contrast-enhanced imaging relative to unenhanced imaging and the SNR of Child-Pugh class A was significantly higher than that of Child-Pugh class B at both in-phase (p<0.001) and opposed-phase (p=0.022) imaging. In addition, the SE of class A was significantly higher than that of class B at in-phase imaging (p=0.004). Cirrhotic liver showed heterogeneous enhancement in 20 of 35 patients (57%), whereas normal liver showed homogeneous enhancement in all patients. CONCLUSION: At Gd-BOPTA-enhanced delayed MR imaging, cirrhotic liver showed less enhancement than normal liver. In cirrhotic patients, hepatic enhancement and hepatic function decreased in tandem. Gd-BOPTAenhanced delayed MR imaging may be useful for evaluating the functional reserve of the liver.

Three-Dimensional Computed Tomographic Angiography with Volume Rendering Technique in the Evaluation of Intracranial Aneurysms: Comparison with Three-Dimensional Digital Subtraction Angiography

PURPOSE: The author compared three-dimensional computed tomographic angiography with combined volume rendering technique (3D-CTA VR) with three-dimensional digital subtraction angiography (3D-DSA) in the detection and characterization of intracranial aneurysms, in order to assess the diagnostic capability of 3D-CTA VR. MATERIALS AND METHODS: This study included 50 patients with suspected intracranial aneurysm who underwent both 3D-CTA VR and 3D-DSA, and who were subsequently confirmed as having aneurysms by intracranial operation or other neurointerventional procedures. The detectability and the characteristics of the aneurysms, such as their aneurysmal neck, direction, and vasospasm of the adjacent vessels, were evaluated retrospectively. RESULTS: Sixty-five intracranial aneurysms were detected through surgery or other interventional procedures. 3D-DSA was more sensitive (96.92%) than 3D-CTA VR in the detection of the aneurysms. All of the aneurysms that were more than 3mm in size were detected with both techniques. 3D-DSA failed to reveal one posterior communicating artery aneurysm, while 3D-CTA VR missed three aneurysms. The aneurysmal necks were clearly visualized in 58 of 61 aneurysms (95.1%) on 3D-CTA VR, but all of the aneurysmal necks(100%) were clearly identified on 3D-DSA. CONCLUSION: 3D-CTA combined with VR technique showed good sensitivity for the depiction of intracranial aneurysms greater than 3 mm in size, and its usefulness in characterizing the aneurysms for surgical or endovascular treatment planning was equal to or less than that of 3D-DSA.

The Usefulness of Perfusion CT in Acute Cerebral Ischemic Infarction

PURPOSE: To determine the usefulness of cerebral perfusion computed tomography (CT) in patients with acute cerebral ischemic infarction. MATERIALS AND METHODS: Twelve patients with acute middle cerebral artery infarction underwent conventional CT and cerebral perfusion CT within 25 hours of the onset of symptoms. For each patient, perfusion CT scans were obtained at the levels of the basal ganglia and 1 cm caudal to them. Using special imaging software, perfusion imaging maps for cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT), and time to peak (TTP) were created, and the infarcted lesion was evaluated on each map. MTT and TTP delay times were measured in the perfusion defect lesion and symmetric contralateral normal cerebral hemisphere. Lesion size on each perfusion map was determined and compared with the value obtained by diffusionweighted MR imaging (DWMRI). RESULTS: In all patients, perfusion CT maps depicted the perfusion defect lesion, for which the MTT and TTP delay was remarkable. A comparison of lesion size between each perfusion map and DWMR images showed that the closest correlation involved CBF maps (8/12, 67%). On MTT maps, the lesion was larger than at DWMRI, suggesting that MTT mapping can be used to evaluate ischemic penumbra. CONCLUSION: Perfusion mapping facilitates the evaluation not only of the ischemic core and ischemic penumbra, but also of hemodynamic status in the area of the perfusion defect. This finding demonstrates that perfusion CT can be useful for the diagnosis and treatment of patients with acute cerebral ischemic infarction.

Bronchial Artery and Non-bronchial Systemic Artery Embolization for the Treatment in Patients with Hemoptysis: Analysis of Efficacy of Gelfoam Single Use

PURPOSE: To investigate the efficacy of Gelfoam single use for the management of hemoptysis by analyzing patients with recurrence in embolized artery and other artery, respectively. MATERIALS AND METHODS: Between 1992 and 2000, 131 patients (104 men and 27 women, mean age: 54.4 years) with hemoptysis underwent BAE using gelatin sponge only. After puncturing the femoral artery using the Seldinger method, angiographies of the thoracic aorta, the bronchial arteries, the intercostal arteries, and the systemic collaterals which were suspected of bleeding focus and embolization were performed. Gelfoam was used 1x3 mm and 2x3 mm or 2x5 mm by the diameter of feeding arteries. The cumulative hemoptysis control rate and recurrence rate were analyzed from the previously embolized vessels. RESULTS: Hemoptysis were recurred among 34 of 131 patients. Twenty-two patients had a recurrence from the same vessels and 12 from the different ones. Using the Kaplan-Meier method, the cumulative hemoptysis control rate was obtained in the patients with a recurrence from the same vessels: 88.8% in 1 month, 79.9% in 1 year, and 77.3% in 2 year. The reasons for recurrences of the same lesions are as follows; due to the tortuosity of the vessel (n=3); partial embolization through the common trunk formation between bronchial and anterior spinal artery (n=3); by vessel spasms or autogenous thrombus (n=2); due to the contrast media hypersensitivity (n=1). These 9 patients were not treated successfully. In the remaining 13 cases, hemoptysis were recurred due to recanalization of embolized vessels. Among 161 procedure, complications consisted of fever (n=8), dyspnea (n=8), mild chest discomfort (n=7), lower back pain (n=1), and transient lower leg paralysis (n=1), which were improved within several days. There was no serious complication in this study. CONCLUSION: Bronchial artery embolization using Gelfoam alone maybe effective and safe to control hemoptysis.

Multidetector-row CT Angiography of Hepatic Artery: Comparison with Conventional Angiography

PURPOSE: To determine the usefulness of three-dimensional CT angiography using multidetector-row CT (MDCT) for delineating the arterial anatomy of the liver. MATERIALS AND METHODS: Hepatic arterial three-dimensional CT angiography was performed using MDCT (Lightspeed Qx/I; GE Medical Systems, Milwaukee, Wis., U.S.A.) in 45 patients with HCC undergoing conventional angiography for transcatheter hepatic arterial chemoembolization. The scanning parameters during the early arterial phase were 2.5 mm slice thickness, 7.5 mm rotation of table speed, and a pitch of 3. Images were obtained by one radiologist using maximum intensity projection from axial CT images obtained during the early arterial phase. Two radiologists blinded to the findings of conventional angiography independently evaluated the hepatic arterial anatomy and the quality of the images obtained. RESULTS: Compared with conventional angiography, reader A correctly evaluated the hepatic arterial anatomy depicted at three-dimensional CT angiography. Reader B's evaluation was correct in 40 of 45 patients. Interobserver agreement was good (kappa value, 0.73), and both readers assessed the quality of three-dimensional CT angiography as excellent. CONCLUSION: Three-dimensional CT angiography using MDCT was accurate for delineating the arterial anatomy of the liver, and interobserver agreement was good. The modality may provide, prior to conventional angiography, valuable information regarding a patient's hepatic arterial anatomy.

Metallic Stent Implantation in Patients with Iliac Artery Occlusion: Long-term Patency Rate and Factors Related to Recurrence

PURPOSE: To determine the long-term patency rate in 68 patients with iliac artery occlusion who underwent metallic stent implantation, and to analyze the factors related to recurrence. MATERIALS AND METHODS: Sixty-eight patients with occlusive disease of the iliac artery underwent implantation of a self-expandable metallic stent. The clinical symptoms were intermittent claudication (n=48), resting pain (n=11), and gangrene (n=9). Stent patency was determined by follow-up angiography and color Doppler imaging, and the cumulative patency rate using the Kaplan-Meier method. Cox's proportional hazard model was used to analyse recurrence-related factors involving clinical symptoms (Fontaine stage), risk factors, and anatomical factors such as lesion location, length, and the development of collaterals. The duration of followup varied from 1 day to 73 months (mean, 23.8 months). RESULTS: Arterial occlusion recurred in 16 of 68 patients (23.5%), and the cumulative patency rate was as follows: 95.4% at one month, 93.2% at six months, 80.1% at one year, 73.2% at two years, 68.9% at three years, and 62% at five years. According to a statistical analysis of risk factors, the recurrence p=0.04) than in those without it, but in patients who smoked, hypertension, DM, and previous cerebrovascular disease were not statistically significant. With regard to anatomical factors, the recurrent rate for lesions involving the external iliac artery was 6.5 times higher (p=0.02) than for those involving the common iliac artery. Variations in the Fontaine stage were not statistically significant indicators of recurrence. CONCLUSION: The recurrence rate after implantation of an iliac artery stent is higher in patients with heart disease than in those without it, and higher for occlusive lesions involving the external iliac artery than for those of the common iliac artery.

Acute Cerebral Infarction in a Rabbit Model: Perfusion and Diffusion MR Imaging

PURPOSE: The present study was undertaken to evaluate the usefulness of cerebral diffusion (DWI) and perfusion MR imaging (PWI) in rabbit models with hyperacute cerebral ischemic infarction. MATERIALS AND METHODS: Experimental cerebral infarction were induced by direct injection of mixture of Histoacryl glue, lipiodol, and tungsten powder into the internal cerebral artery of 6 New-Zealand white rabbits, and they underwent conventional T1 and T2 weighted MR imaging, DWI, and PWI within 1 hour after the occlusion of internal cerebral artery. The PWI scan for each rabbit was obtained at the level of lateral ventricle and 1cm cranial to the basal ganglia. By postprocessing using special imaging software, perfusion images including cerebral blood volume (CBV), cerebral blood flow (CBF), and mean transit time (MTT) maps were obtained. The detection of infarcted lesion were evaluated on both perfusion maps and DWI. MTT difference time were measured in the perfusion defect lesion and symmetric contralateral normal cerebral hemisphere. RESULTS: In all rabbits, there was no abnormal signal intensity on T2WI. But on DWI, abnormal high signal intensity, suggesting cerebral infarction, were detected in all rabbits. PWI (rCBV, CBF, and MTT map) also showed perfusion defect in all rabbits. In four rabbits, the calculated square of perfusion defect in MTT map is larger than that of CBF map and in two rabbits, the calculated size of perfusion defect in MTT map and CBF map is same. Any rabbits do not show larger perfusion defect on CBF map than MTT map. In comparison between CBF map and DWI, 3 rabbits show larger square of lesion on CBF map than on DWI. The others shows same square of lesion on both technique. The size of lesion shown in 6 MTT map were larger than DWI. In three cases, the size of lesion shown in CBF map is equal to DWI. But these were smaller than MTT map. The calculated square of lesion in CBF map, equal to that of DWI and smaller than MTT map was three. And in one case, the calculated square of perfusion defect in MTT map was largest, and that of DWI was smallest. CONCLUSION: DWI and PWI may be useful in diagnosing hyperacute cerebral ischemic infarction and in evaluating the cerebral hemodynamics in the rabbits.

Functional MR Imaging Using BOLD Technique in Patients with Brain Tumors

PURPOSE: To reveal clinical usefulness of functional MRI (fMRI) using sensorymotor and language stimuli for demonstrating anatomic relationship between sensorimotor or language cortices and lesions in the planning of brain tumor surgery. MATERIALS AND METHODS: This study included 12 right-handed patients with brain tumors in or around sensorimotor or language cortices. Eleven patients were evaluated with primary motor and sensory stimuli. Of these patients, six patients were also evaluated with language stimuli. One patient was evaluated with language stimuli only. For fMR imaging, a 1.5T scanner was used and the EPI BOLD technique was employed. For postprocessing image, the SPM99 program and a program made by our department was utilized. We evaluated whether sensorimotor and language stimuli activate sensorimotor and language cortices. And also, clinical efficacy of revealing anatomic relationship between cerebral cortices and lesions for planning neurosurgical operation were evaluated. Finally, we compared post-operative neurologic function with pre-operative neurologic function in same patients. RESULTS: The fMRI examination was successful in identifying the functional cortices and depicting anatomic relationship between functional cortices and lesions in all patients. In nine patients of 11 patients with identified sensorimotor cortices, postoperative grade of manual motor test was not changed, compared with preoperative grade. Whereas postoperative improved than preoperative grade in one patient of remaining two patients, postoperative aggravated than preoperative grade in the other. This result was due to atherosclerotic lacunar infarction, regardless of tumor resection. Postoperative deficit of language function was not found in seven patients with identified language cortices. CONCLUSION: fMRI could be a helpful method for determining the best approach to neurosurgical treatment in patients with brain tumors in or around sensorimotor or language cortices.

Influential Factors of Clinical Outcome of Local Intra-Arterial Thrombolysis using Urokinase in Patients with Hyperacute Ischemic Stroke

PURPOSE: To evaluate the clinical outcome and other relevant factors in cases where local intra-aterial thrombolysis (LIT) is used for the threatment of hyperacute ischemic stroke. MATERIALS AND METHODS: Forty-eight hyperacute ischemic stroke patients were treated by LIT, using urokinase, within six hours of ictus, and for evaluation of their neurological status, the National Institutes of Health Stroke Scale (NIHSS) score was used. Angiographic recanalization was classified according to Mori recanalization grades. Three months after LIT, the outcome was assessed by clinical examination using the modified Rankin scale (good outcome: RS=0-3; poor outcome: RS=4-6). In all patients, the findings of pre- and post- LIT CT, and angiography, as well as neurological status and hemorrhagic complications, were also analysed. RESULTS: Thirty-three patients had occlusions of the middle cerebral artery (MCA), and 15, of the internal carotid artery (ICA). The NIHSS score averaged 16.9 at the onset of therapy and 13.5 at 24 hours later. Successful recanalization (Mori grade 3,4) was achieved in 28 (58.3%) of 48 patients, but in 20 (41.7%) the attempt failed. Twenty-two (45.8%) of the 48 patients had a good outcome, but in (54.2%) the outcome was poor. Thirteen (40.6%) of 32 patients with MCA occlusions and 13 (81.2%) of 16 with ICA occlusions had a poor outcome. Eight patients (16.7%) died. Overall, hemorrhages occured in 20 (41.7%) of 48 patients, with symptomatic hemorrhage in ten. Five (50%) of these ten died. CONCLUSION: LIT using urokinase for hyperacute ischemic stroke is feasible; patients with MCA occlusions had better outcomes than those with ICA occlusions. Hemorrhagic complications of LIT were frequent, and in cases of symptomatic hemorrhage a fatal outcome may be expected.