Imaging findings of vertebral osteomyelitis caused by nontuberculous mycobacterial organisms: Three case reports and literature review.

RATIONALE: Prompt diagnosis of nontuberculous Mycobacterial (NTM) vertebral osteomyelitis is challenging, yet necessary to prevent serious morbidity and mortality. Here, we report 3 cases of vertebral osteomyelitis caused by NTM with imaging findings. PATIENT CONCERNS: Case 1, a 58-year-old male patient, was admitted to our hospital because of the presence of a pulmonary mass for 6 months with cough and chest pain.Case 2, a 50-year-old male patient, had fever and cough for 3 years and was diagnosed with tuberculosis. Antituberculosis treatment was ineffective, accompanied by lymph node enlargement and osteosclerotic changes involving vertebral bodies.Case 3, a 66-year-old female patient, was admitted to our hospital with a mass on the top of her head for 1 month, which ruptured in the last 2 weeks. DIAGNOSES: Case 1: Sputum culture revealed Mycobacterium (M.) avium.Case 2: The final culture results of the lymph node biopsy samples were M. intracellulare.Case 3: Culture results of the sputum and pus from the abscess were M. gordon.We found sclerosing lesions in the spine in all 3 NTM patients, which were easily misdiagnosed as metastatic tumors. In 2 cases, there was bone destruction in the ilium with limbic sclerosis, and there were abscesses near the ilium and in front of the sacrum in 1 case. INTERVENTIONS: Case 1 was transferred to other specialist hospital.Case 3 received surgical treatment for cranial lesions and abscess drainage.Case 2 and case 3 received targeted treatment for nontuberculous mycobacteria in our hospital. OUTCOME: The condition of case 1 was unknown.Recovery of case 2 was uneventful because of prolonged illness; however, inflammation gradually improved overall.Case 3 had no recurrence following surgical treatment. LESSONS: In our 3 cases of NTM vertebral osteomyelitis, bone lesions were often misdiagnosed as bony metastases because of the presence of multiple sclerotic lesions. Diagnoses were challenging and delayed. It is important to consider osteomyelitis by NTM when disseminated osteosclerosis with or without osteolytic bone lesions is present in conjunction with continuous inflammatory symptoms and signs. Moreover, an open biopsy of the lesion should be performed for a definitive diagnosis.

Using Real-Time Fusion Imaging Constructed from Contrast-Enhanced Ultrasonography and Magnetic Resonance Imaging for High-Grade Glioma in Neurosurgery.

OBJECTIVE: To compare the observation of high-grade glioma (HGG) based on intraoperative multiplane ultrasonography (US) images and preoperative reconstructive coplanar T1-weighted enhanced magnetic resonance imaging (MRI) using volume navigation (V Nav) fusion image technology. METHODS: We retrospectively evaluated intraoperative data obtained from 16 patients diagnosed with HGG (grade III and IV). Overall, 18 nodules observed in 15 patients were examined. HGG images from US and contrast-enhanced US (CEUS) were compared with those from preoperative reconstructive coplanar enhanced T1-weighted MRI using automatic V Nav fusion image technology. RESULTS: All HGG tumors were detected. Images of 13 of 18 tumors (72.2%) with obscure margins using B-mode US were improved with clear tumor boundaries using CEUS imaging. The relative difference in tumor area between CEUS and enhanced MRI modalities in 14 mainly solid component lesions was considered statistically significant (P value < 0.05). There was a perfect correlation of the enhanced area between coplanar CEUS and enhanced MRI. CONCLUSIONS: The V Nav fusion image system combining intraoperative real-time US imaging with reconstructive preoperative coplanar MRI is valuable for image-guided HGG resection. It is suitable for neurosurgeons who lack the expertise in US technology to discern the brain structure and allows better recognition of tumor and edema tissues compared with reconstructive preoperative coplanar-enhanced MRI in real time and in multiplane from different angles. In addition, CEUS combined with B-mode US could improve tumor detection and resection control in neurosurgery, even in single US-guided operations.

The real-time ultrasonography for fusion image in glioma neurosugery.

OBJECTIVES: The aim of study is to evaluate the general performance and efficiency of the using real time intraoperative ultrasound system with Volume Navigation system technology in glioma. Compare glioma intraoperative ultrasound and contrast agent ultrasound images to obtained preoperative MRI with fusion image in a real-time. PATIENTS AND METHODS: Fifteen patients had been performed fusion imaging involved intraoperative real-time ultrasound and contrast agent ultrasound with preoperative MR imaging including preoperative gadolinium-enhanced MRI from March 2017 to December 2017. The number of tumor was counted online fusion imaging in real time ultrasound with and without preoperative MR. We analyzed ultrasound coplanar MR modalities in real time including tumor location, margin (obscure or defined). In addition, intraoperative ultrasound enhancement pattern was analyzed compare it to preoperative reconstruction gadolinium-enhanced T1-weighted MRI. Two radiologists who made planning ultrasound assessment for the focus lesion based on a 4 scoring system according to the degree of confidence. RESULTS: Thirteen of fifteen patients whose automatically registration successful intraoperative neurosurgery accepted preoperative MR examination. Seven of fifteen fine-tuning registration phase were performed and satisfactory with fusion image substantially. Intraoperatively, 73.3% (11/15) glioma nodules were definite on conventional B-mode US by a radiologist who doesn't know the MR result before fusion US with MRI. However, 100% tumors were detected on fusion B-mode ultrasound imaging with MRI. Two radiologists evaluated the score between fusion B-mode ultrasound and CEUS with coplanar MRI and had a result that score was upgraded in 69.2% (9/13) and 84.6% (11/13) patients. Inter-observer agreement was significant (kappa value = 1.0, p < 0.001) in B-mode ultrasound fusion image with MRI. Inter-observer agreement was moderate (kappa value = 0. 0.618, p < 0.001) in CEUS fusion image with MRI. CONCLUSION: Fusion imaging is very useful to detect poor sonographic visibility tumor on fusion B-mode US imaging with MR images. Fusion image may demonstrate multiplane images including same standard and nonstandard MRI and US images to help localize tumor. The additional real time fusion CEUS mode image with MR is a safe method for neurosurgery and the use of CEUS should be considered when fusion B-mode ultrasound imaging alone is not satisfactory for margin.

Abnormal brain function in neuromyelitis optica: A fMRI investigation of mPASAT.

PURPOSE: Cognitive impairment with the Neuromyelitis Optica (NMO) patients is debated. The present study is to study patterns of brain activation in NMO patients during a pair of task-related fMRI. MATERIALS AND METHODS: We studied 20 patients with NMO and 20 control subjects matched for age, gender, education and handedness. All patients with NMO met the 2006 Wingerchuk diagnostic criteria. The fMRI paradigm included an auditory attention monitoring task and a modified version of the Paced Auditory Serial Addition Task (mPASAT). Both tasks were temporally and spatially balanced, with the exception of task difficulty. RESULTS: In mPASAT, Activation regions in control subjects included bilateral superior temporal gyri (BA22), left inferior frontal gyrus (BA45), bilateral inferior parietal lobule (BA7), left cingulate gyrus (BA32), left insula (BA13), and cerebellum. Activation regions in NMO patients included bilateral superior temporal gyri (BA22), left inferior frontal gyrus (BA9), right cingulate gyrus (BA32), right inferior parietal gyrus (BA40), left insula (BA13) and cerebellum. Some dispersed cognition related regions are greater in the patients. CONCLUSIONS: The present study showed altered cerebral activation during mPASAT in patients with NMO relative to healthy controls. These results are speculated to provide further evidence for brain plasticity in patients with NMO.

The capability of inflow inversion recovery magnetic resonance compared to contrast-enhanced magnetic resonance in renal artery angiography.

PURPOSE: To assess the capability of inflow inversion recovery (IFIR) magnetic resonance angiography (MRA), compared with contrast-enhanced MRA (CE-MRA) as reference standard, in evaluating renal artery stenosis (RAS). METHODS: Seventy-two subjects were examined by IFIR MRA with respiratory-gated, prior to CE-MRA with a 1.5-T scanner. Two readers evaluated the quality of IFIR MRA images and renal artery depiction on artery-by-artery basis. The agreement of two methods to assess RAS was analyzed using the Kappa test. The relationship between image quality of IFIR MRA and respiratory rate was analyzed by ANOVA test. RESULTS: The visibility of renal artery branch vessels was significantly higher using IFIR MRA than CE-MRA (p < 0.05). A good agreement of two methods in evaluating stenosis grade, and a near-perfect inter-observer agreement for IFIR MRA (Kappa value 0.98) and CE-MRA (Kappa value 0.93), were demonstrated. As RAS ≥50%, the sensitivity and specificity of IFIR MRA were 92 and 98% in reader 1, 93 and 98% in reader 2, respectively. The image quality was significantly better in patients with stable respiration (p < 0.01). CONCLUSIONS: IFIR MRA in patients with stable respiration has higher visibility of renal artery branch vessels than CE-MRA, and a good agreement with CE-MRA in evaluating stenosis grade. It could be used to evaluate RAS for screening, and monitoring treatment.

Atypical central neurocytoma with metastatic craniospinal dissemination: a case report.

Central neurocytomas comprise nearly half of adult intraventricular neoplasms. The median age of onset is 34 years. It is typically a low-grade neoplasm (World Health Organization grade II), although some cases of malignant neurocytomas have been described. We present a rare case of an atypical central neurocytoma with craniospinal dissemination, including both imaging and pathologic findings.

Intrinsic Functional Plasticity of the Thalamocortical System in Minimally Disabled Patients with Relapsing-Remitting Multiple Sclerosis.

The thalamus plays a crucial role in sensorimotor, cognitive, and attentional circuit functions. Disruptions in thalamic connectivity are believed to underlie the symptoms of multiple sclerosis (MS). Therefore, assessing thalamocortical structural connectivity (SC) and functional connectivity (FC) may provide new insights into the mechanism of intrinsic functional plasticity in a large-scale neural network. We used resting-state FC measurement and diffusion tensor imaging probabilistic tractography to study the functional and structural integrity of the thalamocortical system in patients with relapsing-remitting MS (RRMS) and matched healthy controls. In the thalamocortical connections of RRMS patients, we found lesion load-related regional FC in the right temporal pole, which reflected compensatory hyperconnectivity related to lesion-related demyelination. We also found significant correlations between increased diffusivity and slowed cognitive processing (PASAT) or the impact of fatigue (MFIS-5), as well as between connective fiber loss and disease duration. Taken together, the evidence from SC and FC analysis of the thalamocortical system suggests that minimally disabled RRMS patients exhibit a dissociated SC-FC pattern and limited regional functional plasticity to compensate for the chronic demyelination-related loss of long-distance SC. These results also provide further evidence supporting the notion that MS is a disorder of anatomical disconnection.

Leukoencephalopathy with cerebral calcifications and cysts: clinical and pathological features in two adults.

Two adult patients diagnosed with Leukoencephalopathy with cerebral calcifications and cysts (LCC) were presented. Both patients had a long-term (8-10 years) following-up. Radiological findings of both patients revealed the characteristic signs of LCC: cerebral white matter abnormalities, calcifications, and cysts. In case 1, the initial CT scan showed a low-density area in the right frontal lobe and it had developed into a large cystic lesion after 8 years. Histopathological determination revealed that the cyst wall was associated with hemorrhage, angiomatous formation, and some Rosenthal fibers. In case 2, a major cystic lesion was located at the left parietal lobe which was resected and an old hematoma was found inside the cyst. Nine years later, the follow-up neuroimaging of case 2 showed a remarkable improvement of white matter abnormalities and cystic lesions. Hemorrhagic fluid was observed inside the cysts. Additionally, follow-up CT and MR scans showed a rapid enlargement of cystic lesions accompanied with hemorrhagic fluid levels after a year. Then, a major cyst was surgically removed to relieve pressure symptoms. Pathology of the resected cyst exhibited an organized hemorrhage inside the cyst and a large amount of hemosiderin surrounding the cyst wall. In conclusion, our two cases demonstrated that angiomatous changes subsequent with hemorrhage may be the major mechanism of cyst formation and development.

The imaging features of neurologic complications of left atrial myxomas.

BACKGROUND: Neurologic complications may be the first symptoms of atrial myxomas. Understanding the imaging features of neurologic complications of atrial myxomas can be helpful for the prompt diagnosis. OBJECTIVE: To identify neuroimaging features for patients with neurologic complications attributed to atrial myxoma. METHODS: We retrospectively reviewed the medical records of 103 patients with pathologically confirmed atrial myxoma at Xiangya Hospital from January 2009 to January 2014. The neuroimaging data for patients with neurologic complications were analyzed. RESULTS: Eight patients with atrial myxomas (7.77%) presented with neurologic manifestations, which constituted the initial symptoms for seven patients (87.5%). Neuroimaging showed five cases of cerebral infarctions and three cases of aneurysms. The main patterns of the infarctions were multiplicity (100.0%) and involvement of the middle cerebral artery territory (80.0%). The aneurysms were fusiform in shape, multiple in number (100.0%) and located in the distal middle cerebral artery (100.0%). More specifically, high-density in the vicinity of the aneurysms was observed on CT for two patients (66.7%), and homogenous enhancement surrounding the aneurysms was detected in the enhanced imaging for two patients (66.7%). CONCLUSION: Neurologic complications secondary to atrial myxoma consist of cerebral infarctions and aneurysms, which show certain characteristic features in neuroimaging. Echocardiography should be performed in patients with multiple cerebral infarctions, and multiple aneurysms, especially when aneurysms are distal in location. More importantly, greater attention should be paid to the imaging changes surrounding the aneurysms when myxomatous aneurysms are suspected and these are going to be the relevant features in our article.

Increased thalamic intrinsic oscillation amplitude in relapsing-remitting multiple sclerosis associated with the slowed cognitive processing.

OBJECTIVE: To investigate the relationship between the amplitude of thalamic intrinsic neuronal activity, structural imaging indices, and the clinical neurological scales in relapsing-remitting multiple sclerosis (RRMS). METHODS: Twenty-three patients with RRMS and 23 healthy controls were examined by resting-state fMRI (rs-fMRI) scan. Thalamic intrinsic oscillation amplitude was calculated by amplitude of low frequency fluctuation (ALFF) of rs-fMRI, as well as its correlations with clinical and structural imaging indices. RESULTS: Compared with the healthy controls, RRMS patients showed significantly increased ALFF values in bilateral thalami (P<.05, corrected). In the patient group, positive correlation was found between bilateral ALFF values and paced auditory serial addition test (left: P=.033; right: P=.016). Significant correlation was detected between the ALFF values and fractional anisotropy (FA) values in the left thalamus (r=0.550, P=.007); only tendency increased correlation was detected between the ALFF values and FA values in the right thalamus (P=.114). No correlation was observed between bilateral thalamic ALFF values and disease duration, expanded disability status scale score, brain parenchymal fraction, or total white matter lesion loads (P>.05). CONCLUSION: The increased thalamic intrinsic oscillation amplitude as an ineffective reorganization was responded to microstructural damage in the RRMS patients, as well as it was associated with the slowed cognitive processing in relatively minimally disabled stage.

Effect of intravenous gadolinium-DTPA on diffusion-weighted imaging of brain tumors: a short temporal interval assessment.

PURPOSE: To determine the effect of intravenous administration of gadolinium (Gd) contrast medium (Gd-DTPA) on diffusion-weighted imaging (DWI) for the evaluation of normal brain parenchyma vs. brain tumor following a short temporal interval. MATERIALS AND METHODS: Forty-four DWI studies using b values of 0 and 1000 s/mm(2) were performed before, immediately after, 1 min after, 3 min after, and 5 min after the administration of Gd-DTPA on 62 separate lesions including 15 meningioma, 17 glioma and 30 metastatic lesions. The signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and apparent diffusion coefficient (ADC) values of the brain tumor lesions and normal brain tissues were measured on pre- and postcontrast images. Statistical analysis using paired t-test between precontrast and postcontrast data were obtained on three brain tumors and normal brain tissue. RESULTS: The SNR and CNR of brain tumors and the SNR of normal brain tissue showed no statistical differences between pre- and postcontrast (P > 0.05). The ADC values on the three cases of brain tumors demonstrated significant initial increase on the immediate time point (P < 0.01) and decrease on following the 1 min time point (P < 0.01) after contrast. Significant decrease of ADC value was still found at 3min and 5min time point in the meningioma group (P < 0.01) with gradual normalization over time. The ADC values of normal brain tissues demonstrated significant initial elevation on the immediately postcontrast DWI sequence (P < 0.01). CONCLUSION: Contrast medium can cause a slight but statistically significant change on the ADC value within a short temporal interval after the contrast administration. The effect is both time and lesion-type dependent.

Is there an impact of 18F-FDG PET/CT on the surveillance and clinical management of recurrent ovarian cancer? Research based on a large sample in a single PET/CT center.

OBJECTIVES: The aim of the study was to evaluate the use of F-fluorodeoxyglucose ((18)F-FDG) PET/computed tomography (CT) in the follow-up and clinical management of ovarian cancer patients after therapy. MATERIALS AND METHODS: A total of 152 ovarian cancer patients who had undergone therapy were evaluated. Clinical information, CA-125 levels, and traditional imaging findings were analyzed. According to the indication for PET/CT the patients were divided into five groups for assessing the role of (18)F-FDG PET/CT in the clinical management of ovarian cancer patients after therapy. A comparison was made between the PET/CT findings and the results of clinical follow-up. RESULTS: Of the 152 patients, 137 had follow-up results and 15 were lost to follow-up. A total of 105 patients were found to have recurrent tumor and 32 were found to be disease-free after long-term follow-up. The diagnostic sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were 98.3, 91.2, 96.8, 97.5, and 93.9%, respectively. PET/CT was especially useful in patients when indications were to diagnose suspected recurrence, assess disease progression, and evaluate therapeutic response. CONCLUSION: PET/CT has been proven to be extremely valuable in the evaluation of patients with recurrent ovarian cancer and is particularly helpful in guiding treatment planning.

Somatotopic reorganization of hand representation in bilateral arm amputees with or without special foot movement skill.

Bilateral arm amputees usually are excellent foot users. To explore the plasticity of the primary motor cortex in upper-extremities amputees and to determine if the acquisition of special foot movement skill is related with the bilateral hand amputation, we studied the primary motor cortex by using combined task and resting state functional magnetic resonance imaging (fMRI). We investigated 6 bilateral arm amputees with or without special foot movement skill. In the task fMRI study, we found that toe tapping of all the amputees activated the bilateral hand area, including cases without special foot skill. In addition, cases without special foot skill mainly activated the precentral gyrus, which differed from those with more adept foot motor skill who activated both the precentral and postcentral gyri. To further understand the plasticity of the hand area, the resting state functional connectivity was investigated between the foot and hand regions. One-tailed two-sample t-test suggested that the connections between two areas became significantly stronger in the amputee group. Our study demonstrates that hand region of the cortex does not remain 'silent' after bilateral arm amputation, but rather is recruited by other modalities such as adjacent or nonadjacent cortexes to process motor information in a functionally relevant manner. From the data presented, it seems that the bilateral arm amputees have a strong potential to develop new skills in their remaining extremities and practice may further enhance this potential.

Magnetic resonance imaging features of pathologically proven cerebral sparganosis.

OBJECTIVE: The purpose of this study was to identify characteristic magnetic resonance imaging (MRI) features of cerebral sparganosis, a rare parasitic disease caused by the plerocercoid larva of Spirometra mansoni. METHODS: This retrospective study reviewed medical records, computed tomography (CT) and MRI scans and pathological specimens from patients with pathologically proven cerebral sparganosis. The location, signal intensity and contrast enhancement characteristics of the lesions were assessed. RESULTS: Records of 12 patients (seven male and five female; age range 8-35 years) were reviewed. A total of 13 lesions were identified: of the 10 patients with supratentorial lesions, nine had a single lesion and one had bilateral hemispheric lesions. Two patients had a single lesion in the ependyma of the 4(th) ventricle. All lesions were iso-hypointense on T1-weighted images, slightly hypointense on T2-weighted images and surrounded by extensive oedema. Ten of the 13 lesions demonstrated a 'string-knots sign', characterized by a tangled string in a knot-like shape on contrast-enhanced MRI. CONCLUSION: A string-knots sign enhancement pattern in cortical-subcortical regions should suggest the diagnosis of cerebral sparganosis.

Thoracic epidural angiolipoma: A case report and review of the literature.

Angiolipoma of the spine is a benign neoplasm consisting of both mature fatty tissue and abnormal vascular elements, and usually presents with a slow progressive clinical course. Our patient presented with bilateral lower extremity weakness and chest-back numbness. Physical examination revealed adipose elements superficial hypesthesia below the T5 level and analgesia below the T6 level. Magnetic resonance imaging (MRI) scan showed an avidly and heterogeneously enhancing mass which was located in the posterior epidural space. Compression of the thoracic cord by the fusiform mass was seen between T3-T4. During the operation, a flesh pink vascular mass (4.7 cm × 1.0 cm × 1.0 cm) with obscure margin and strong but pliable texture was found in the posterior epidural space extending from T3 to T4. There was no infiltration of the dura or the adjacent bony spine. Histopathological study of the surgical specimen showed a typical angiolipoma. We review the previously documented cases of spinal extradural angiolipomas performed with MRI.

Sensory neuronopathy involves the spinal cord and brachial plexus: a quantitative study employing multiple-echo data image combination (MEDIC) and turbo inversion recovery magnitude (TIRM).

INTRODUCTION: Sensory neuronopathy (SNN) is a distinctive subtype of peripheral neuropathies, specifically targeting dorsal root ganglion (DRG). We utilized MRI to demonstrate the imaging characteristics of DRG, spinal cord (SC), and brachial plexus at C7 level in SNN. METHODS: We attempted multiple-echo data image combination (MEDIC) and turbo inversion recovery magnitude (TIRM) methods in nine patients with sensory neuronopathy and compared with those in 16 disease controls and 20 healthy volunteers. All participants underwent MRI for the measurement of DRG, posterior column (PC), lateral column, and spinal cord area (SCA) at C7 level. DRG diameters were obtained through its largest cross section, standardized by dividing sagittal diameter of mid-C7 vertebral canal. We also made comparisons of standardized anteroposterior diameter (APD) and left-right diameters of SC and PC in these groups. Signal intensity and diameter of C7 spinal nerve were assessed on TIRM. RESULTS: Compared to control groups, signal intensities of DRG and PC were higher in SNN patients when using MEDIC, but the standardized diameters were shorter in either DRG or PC. Abnormal PC signal intensities were identified in eight out of nine SNN patients (89 %) with MEDIC and five out of nine (56 %) with T2-weighted images. SCA, assessed with MEDIC, was smaller in SNN patients than in the other groups, with significant reduction of its standardized APD. C7 nerve root diameters, assessed with TIRM, were decreased in SNN patients. CONCLUSION: MEDIC and TIRM sequences demonstrate increased signal intensities and decreased area of DRG and PC, and decreased diameter of nerve roots in patients with SNN, which can play a significant role in early diagnosis.

Imaging of neurocysticercosis.

Neurocysticercosis (NCC) is an infection of the central nervous system by the Taenia solium larvae, and is the most common cause of acquired epilepsy in endemic regions. The natural history of parenchymal NCC lesions can be divided into 4 stages with unique imaging and clinical features. Evaluation of cysticerci is challenging on conventional magnetic resonance (MR) imaging and computed tomography, and is significantly improved with MR cysternography techniques. Differentiation of NCC lesions from metastatic disease and pyogenic abscesses can be improved with advanced MR imaging including (1)H nuclear MR spectroscopy, diffusion-weighted imaging, and MR perfusion imaging.

Differentiation of white and red thrombus with magnetic resonance imaging: a phantom study.

BACKGROUND: An early identification of the composition of arterial thrombus may have diagnostic, therapeutic, and prognostic implications. The variation of magnetic resonance (MR) signal intensity between white and red thrombi, especially in the susceptibility sensitive MR sequence, remains unknown. Our research was to evaluate the feasibility of MRI in differentiating of white and red thrombi with a phantom study. METHODS: A total of 12 red and 12 white thrombi were prepared with the venous blood. Examination of the phantom was completed using a 3.0T MR unit, including fluid attenuated inversion recovery (FLAIR) T1, T2-weighted imaging (T2WI), FLAIR T2, T2 gradient echo (T2 GRE) imaging, and susceptibility weighted angiography sequences (SWAN). MR signal intensity patterns of the thrombi were objectively classified as hyperintensity, isointensity and hypointensity, compared with the background agar. The volume of thrombus was calculated and correlated with its signal intensity. RESULTS: For white thrombi, 11/12 clots showed hyperintensity and 1/12 showed isointensity in FLAIR T1 images. In T2WI, 6/12 clots showed hyperintensity, 3/12 isointensity, and 3/12 hypointensity. In FLAIR T2, 8/12 clots showed hyperintensity and 4/12 showed isointensity. In T2 GRE, 3/12 clots showed hyperintensity and the remaining 9/12 clots showed isointensity. In SWAN, 5/12 clots demonstrated hyperintensity and 7/12 isointensity. For the red thrombus, 12/12 clots demonstrated hyperintensity in FLAIR T1, T2WI, and FLAIR T2 sequences. In T2 GRE and SWAN sequences, 3/12 clots displayed hypointensity and the remaining 9/12 clots showed slight hyperintensity. Thrombi with hypointensity displayed in T2 GRE and SWAN sequences were significantly larger than those with hyperintensity. CONCLUSIONS: Differentiation of white and red thrombi with conventional MR sequence is unreliable, because both kinds of thrombi do not possess unique signal intensity features in these sequences. Red thrombus may or may not show hypointensity in the susceptibility sensitive MR sequences, depending on its size and time course.

Gadobenate dimeglumine-enhanced liver magnetic resonance imaging: value of hepatobiliary phase for the detection of focal liver lesions.

OBJECTIVE: The objective of the study was to determine the value of addition of hepatobiliary phase to dynamic gadobenate dimeglumine (Gd-BOPTA)-enhanced imaging for the detection of focal liver lesions (nodules with diameter ≤3.0 cm). METHODS: Routine nonenhanced magnetic resonance images were obtained in 25 patients with focal liver lesions suggested by ultrasonography and/or computed tomography.T1-weighted dynamic gradient-echo images were acquired immediately and 100 minutes after bolus injection of Gd-BOPTA. The number of the lesions detected by T1-weighted imaging, T2-weighted imaging, diffusion-weighted imaging, dynamic contrast-enhanced, and delayed hepatobiliary-phase imaging was counted, respectively. Contrast-to-noise ratios were measured for all the sequences including delayed hepatobiliary-phase imaging. The signal intensity and morphologic features of liver parenchyma and lesions were recorded and analyzed. RESULTS: There were 7 patients with hepatocellular carcinomas, 6 with hemangiomas, 7 with metastases, and 5 with cholangiocarcinomas. The delayed hepatobiliary-phase imaging showed a homogeneous enhancement of liver parenchyma and distinctive enhancement features of focal liver lesions. The delayed hepatobiliary-phase imaging was better than diffusion-weighted imaging for the detection of focal liver lesions (P < 0.05). CONCLUSION: The addition of hepatobiliary-phase imaging to Gd-BOPTA-enhanced dynamic imaging increased the sensitivity and accuracy for the detection of focal hepatic lesions.

Temporary occlusion test using a microcatheter.

BACKGROUND: The balloon occlusion test (BOT) is a well-accepted technique for the treatment of large or complex aneurysms. However, this procedure may not be feasible for small arteries such as the posterior inferior cerebellar artery (PICA). We report our experience with endovascular treatment of a fusiform PICA aneurysm employing a microcatheter occlusion test. CASE DESCRIPTION: A 46-year-old male had a fusiform Type I aneurysm with irregular wall in the lateral medullary segment of left PICA. Because the BOT cannot be safely performed in the PICA, we performed a temporary occlusion test using a microcatheter. RESULTS: The microcatheter occlusion test was successfully performed, and endovascular treatment was performed afterward. The patient remained symptom free after the embolization and at one-year follow-up. CONCLUSION: The microcatheter occlusion test is an excellent option for performing an occlusion test for vessels that cannot accommodate a balloon because of their diminutive size.