Dual-energy computed tomography material decomposition improves prediction accuracy of hematoma expansion in traumatic intracranial hemorrhage.

OBJECTIVE: The angiographic spot sign (AS) on CT angiography (CTA) is known to be useful for predicting expansion in intracranial hemorrhage, but its use is limited due to its relatively low sensitivity. Recently, dual-energy computed tomography (DECT) has been shown to be superior in distinguishing between hemorrhage and iodine. This study aimed to evaluate the diagnostic performance of hematoma expansion (HE) using DECT AS in traumatic intracranial hemorrhage. METHODS: We recruited participants with intracranial hemorrhage confirmed via CTA for suspected traumatic cerebrovascular injuries. We evaluated AS on both conventional-like and fusion images of DECT. AS is grouped into three categories: intralesional enhancement without change, delayed enhancement (DE), and growing contrast leakage (GL). HE was evaluated by measuring hematoma size on DECT and follow-up CT. Logistic regression analysis was used to evaluate whether AS on fusion images was a significant risk factor for HE. Diagnostic accuracy was calculated, and the results from conventional-like and fusion images were compared. RESULTS: Thirty-nine hematomas in 24 patients were included in this study. Of these, 18 hematomas in 13 patients showed expansion on follow-up CT. Among the expanders, AS and GL on fusion images were noted in 13 and 5 hematomas, respectively. In non-expanders, 10 and 1 hematoma showed AS and GL, respectively. In the logistic regression model, GL on the fusion image was a significant independent risk factor for predicting HE. However, when AS was used on conventional-like images, no factors significantly predicted HE. In the receiver operating characteristic curve analysis, the area under the curve of AS on the fusion images was 0.71, with a sensitivity and specificity of 66.7% and 76.2%, respectively. CONCLUSIONS: GL on fusion images of DECT in traumatic intracranial hemorrhage is a significant independent radiologic risk factor for predicting HE. The AS of DECT fusion images has improved sensitivity compared to that of conventional-like images.

Pituitary Apoplexy After Leuprolide Therapy in a Breast Cancer Patient: A Case Report.

Pituitary apoplexy (PA) is a clinical syndrome resulting from sudden hemorrhage and/or infarction of the pituitary gland. Recent reports documented the development of PA secondary to treatment with gonadotropin-releasing hormone (GnRH) agonists for prostate cancer. A 52-year-old woman visited our emergency room with a severe headache, occurred 1 day prior. She underwent breast-conserving surgery for breast cancer 1 month prior. She was currently undergoing radiation and hormone therapy, consisting of leuprorelin. Brain contrast-enhanced MRI revealed a pituitary adenoma with internal hemorrhage in the sellar and suprasellar areas. Pachymeningeal enhancement was observed along the retroclival and bilateral frontal areas. The patient was diagnosed with PA and aseptic meningitis. The patient underwent total excision via transsphenoidal surgery 8 days after admission. The patient was pathologically diagnosed with a pituitary adenoma with necrosis. On immunochemical staining, the tumor was positive for follicle-stimulating hormone. The follow-up MRI revealed no evidence of residual tumor or an improved pachymeningeal enhancement. She is currently undergoing follow-up at the neurosurgery and endocrinology outpatient departments with no noted complications. In breast cancer patients receiving GnRH agonist therapy, PA may be rare complication.

Occurrence of Metachronous Intracranial Dural Arteriovenous Fistula after Embolization of Intracranial Dural Arteriovenous Fistula: A Case Report.

Intracranial dural arteriovenous fistula (DAVF) is an abnormal arteriovenous shunt accounting for approximately 10%-15% of all intracranial vascular malformations. Most intracranial DAVFs are solitary, but multiple lesions at different sites can rarely occur. Most intracranial multiple DAVFs are synchronous types, whereas metachronous lesions are relatively uncommon. Herein, we report a rare case of metachronous DAVF occurring after the embolization of a preceding lesion in a 75-year-old female.

Resolved Cerebral Venous Hypertension after Angioplasty of Central Venous Stenosis in a Hemodialysis Patient: A Case Report.

Stenosis of the central veins is a common complication in hemodialysis patients. However, cerebral venous hypertension and neurological symptoms caused by central vein stenosis are relatively rare. We present a rare case of cerebral venous hypertension in a 63-year-old male who showed venous reflux into the dural sinuses due to central venous stenosis on time-of-flight MR angiography. After management for central venous stenosis, the venous reflux disappeared.

A case report of adult-onset Alexander disease clinically presenting as Parkinson's disease: is the comorbidity associated with genetic susceptibility?

BACKGROUND: Alexander disease is a rare neurological disease characterized by progressive spastic quadriparesis and bulbar palsy. Moreover, certain patients with adult-onset Alexander disease were often misdiagnosed as other neurodegenerative disorders. CASE PRESENTATION: Herein, we report an adult a 58-year-old woman presented with typical parkinsonism with good levodopa-responsiveness. The patient's dopamine transporter scanning showed significant striatal depletion, while her brain magnetic resonance imaging revealed bilateral tadpole shape of medulla oblongata and bilateral high signal intensity at both cerebellar dentate nuclei in T2-weighted images, suggesting the possibility of a genetic disorder beyond Parkinson's disease. The patient's genetic test resulted in known pathogenic glial fibrillary acidic protein variant, indicating Alexander disease. CONCLUSION: This unique case highlights genetically diagnosed Alexander disease may present with clinical Parkinson's disease.

Borden Type I Sigmoid Sinus Dural Arteriovenous Fistula Presenting as Subarachnoid Hemorrhage from a Feeding Artery Aneurysm of the Anterior Inferior Cerebellar Artery: A Case Report.

Dural arteriovenous fistula is an acquired vascular anomaly that can cause various symptoms. Here, we report a rare case of Borden type I sigmoid sinus dural arteriovenous fistula presenting as subarachnoid hemorrhage. Bleeding occurred from a side-wall aneurysm in the lateral pontomedullary segment of the anterior inferior cerebellar artery, which was a minor pial feeder. Features on imaging modalities, including brain CT, CT angiography, MR imaging/angiography and digital subtraction angiography, are described with a literature review.

[Evaluation of Cerebral Blood Flow Using Arterial Spin Labeling in Patients with Chronic Kidney Disease]. / 만성 콩팥병 환자들에서 동맥 스핀 표지 기법을 이용한 뇌 관류상태의 평가.

Purpose: This study aimed to compare the brain perfusion status of patients with chronic kidney disease to a normal control group to identify any significant differences. Materials and Methods: The perfusion state of the brain was measured by MRI using the arterial spin labeling technique in 36 patients undergoing hemodialysis due to chronic kidney disease and 36 normal controls. Images were then analyzed in a voxel-wise manner to detect brain areas showing significant perfusion differences between the two groups. Results: Patients with chronic kidney disease showed increased perfusion in the form of large clusters across the right fronto-parieto-temporal lobe and the left parieto-occipital lobe. In addition, perfusion increased in the bilateral thalami, midbrain, pons, and cerebellum (p < 0.01, family-wise error corrected). Conclusion: Brain perfusion appears to increase in patients with chronic kidney disease compared to normal controls. Uremic toxicity is thought to be the cause of this increase as it can cause damage to the microscopic blood vessels and their surrounding structures.

Multi c-BN Coatings by r.f Diode Sputtering and Investigation of Wear Behavior.

Cubic boron nitride (c-BN) films on tool substrates are tendency to delaminate. Therefore, many research groups have studied improvement of c-BN synthesis method and deposition processes due to many potential applications. In this paper, we show that the adhesion property of c-BN layer system can be improved by deposing multi c-BN layers. The multi c-BN layers were deposited by r.f (13.56 MHz) diode sputtering apparatus on cemented carbide tool substrates with a TiAlN adhesion layer. For industrial applications, we performed turning and milling experiments under dry and high speed cutting conditions. In this multi c-BN layer system, the lifetime of the tool is affected by the physical properties of the substrate and coated layers such as substrate grain size, thickness of the TiAlN and first c-BN layer and the total number of c-BN layers in this system. Mostly, fine grain size substrates showed longer lifetimes of over 4 times than raw one. In the turning performance, mono TiAlN layer systems were about two times lower lifetime than mono and multi c-BN layer system, moreover, we could be improved adhesion property for milling performance on tool substrates with binary multi c-BN layer systems under dry and high speed cutting conditions. The new application results of the multi c-BN layer system confirm that the high potential of c-BN coatings on cutting tools.

Recently Uncontrolled Glycemia in Diabetic Patients Is Associated with the Severity of Intracranial Atherosclerosis.

BACKGROUND AND PURPOSE: Diabetes mellitus is a specific risk factor for intracranial atherosclerosis (ICAS) regardless of race. However, it is largely unknown whether poor glycemic control is associated with the severity of ICAS in diabetic patients. METHODS: We selected diabetic patients with acute ischemic stroke who were prospectively registered between March 2005 and December 2015. The patients who had a high-risk source of cardiogenic embolism were excluded. ICAS was graded from 0 to 3 by the number of significant (≥50%) stenoses on intracranial magnetic resonance angiography, and was divided into 4 types: unilateral anterior, bilateral anterior, posterior, and anterior plus posterior. Ordinal and multinomial regression tests were applied for the factors influencing the number and types of ICAS. RESULTS: A total of 774 patients with noncardioembolic acute ischemic stroke with diabetes were enrolled. The multiplicity of ICAS was independently associated with age (odds ratio [OR], 1.035 per 1 year, 1.018-1.052; P < .001), hypertension (OR, 1.992, 1.336-2.965; P = .001), and glycated hemoglobin (HbA1c; OR, 1.207 per 1%, 1.089-1.338; P < .001) in the ordinal regression model. In multinomial regression, bilateral anterior stenosis tended to be correlated with age (OR, 1.042, 1.008-1.077; P = .016) and HbA1c (OR, 1.201 per 1%, .991-1.520; P = .057). Both anterior and posterior stenoses were significantly associated with age (OR, 1.056, 1.029-1.084; P < .001), hypertension (OR, 2.584, 1.404-4.762; P = .002), and HbA1c (OR, 1.272, 1.070-1.511; P = .006). CONCLUSIONS: Age, concomitant hypertension, and HbA1c were factors associated with multiple intracranial stenoses. Further study is warranted to elucidate whether poor glycemic control facilitates ICAS in diabetic patients.

Thyroid Nodules Detected by Contrast-Enhanced Magnetic Resonance Angiography: Prevalence and Clinical Significance.

BACKGROUND AND PURPOSE: Incidental thyroid lesions are frequently found on contrast-enhanced magnetic resonance (CE-MR) angiography. The purpose of this study is to determine the prevalence of thyroid incidentalomas detected by CE-MR angiography and to evaluate their clinical significance by correlation with ultrasound (US) and cytopathological results. MATERIALS AND METHODS: We retrospectively reviewed 3,299 consecutive CE-MR angiography examinations performed at our institution between January 2010 and March 2013. Two radiologists evaluated the CE-MR angiography imaging in consensus regarding the presence, location, and vascularity of thyroid incidentaloma. We correlated these findings with follow-up US and cytopathologic results. RESULTS: The prevalence of thyroid incidentalomas detected by CE-MR angiography was 4.6% (152/3,299 patients). CE-MR angiography showed hypervascularity in 86.8% (145/167), isovascularity in 8.4% (14/167), and hypovascularity in 4.8% (8/167) of thyroid nodules compared to vascularity of thyroid parenchyma. Among the patients with thyroid incidentaloma, 34 patients (22.4%) were followed by US examination, and all 36 nodules on CE-MR angiography were detected on follow-up US. Of these nodules, 9 (25%) nodules were classified as probably benign, 26 (72.2%) as indeterminate, and 1 (2.8%) as suspicious malignant nodule. Among the 16 nodules with available cytopathologic results, 12 nodules were benign, 2 nodules were follicular neoplasm, and 2 nodules showed non-diagnostic results. CONCLUSION: Incidental thyroid nodules were found in 4.6% of CE-MR angiography examinations. Because the high incidence of indeterminate US feature among thyroid incidentaloma, when a thyroid incidentaloma is detected on CE-MR angiography, further evaluation with US should be performed.

Uremic parkinsonism with atypical phenotypes and radiologic features.

Uremic encephalopathy with bilateral basal ganglia lesions has been reported as an acute neurometabolic disease which shows reversible clinical course and brain imaging features. The exact nature and pathophysiology have not been well established. We encountered two patients who showed a relapsing and aggravating course and an atypical phenotype including parkinsonism with paroxysmal dystonic head tremor and acute onset monoparesis of the lower extremity. They also showed unusual radiological findings which revealed combined lesions in the basal ganglia and cortex, persistent hemorrhagic transformation, and focal ischemic lesion in the internal capsule. Herein, we present the unusual phenomenology with atypical radiologic findings and suggest the possible multifactorial pathogenesis of uremic encephalopathy.

Thromboaspiration of arteriovenous hemodialysis graft thrombosis using Desilets-Hoffman sheath: single-center experience.

PURPOSE: The purpose of this study was to evaluate the feasibility, efficacy and safety of percutaneous thromboaspiration with a 7F Desilets-Hoffman sheath compared with previously established percutaneous mechanical thrombectomy techniques in occluded hemodialysis grafts. MATERIALS AND METHODS: One thousand three hundred five patients (767 women, 538 men; mean age, 61.04±13.09 years; mean graft age, 36.64±30.80 mo) with 2,531 episodes of hemodialysis graft thrombosis underwent percutaneous thromboaspiration with a 7F Desilets-Hoffman sheath using criss-cross or apex puncture technique. Technical success rate, procedure time, complications and patency rates were analyzed. RESULTS: Technical success was achieved in 2,426 of 2,531 procedures (95.9%). Average procedure time of the intervention was 42.87±22.77 minutes. Primary patency rate was 61.9% at 3 mo, 41.2% at 6 mo and 19.6% at 1 year. Major complications occurred in 4.1% of cases (23 graft outflow rupture; 68 arterial emboli; 1 arterial dissection; 3 symptomatic pulmonary embolism; 1 stent migration) and minor complications occurred in 7.7% of cases (196 cases). These results were comparable to previously reported mechanical thrombectomy techniques in occluded hemodialysis grafts. CONCLUSIONS: Percutaneous thromboaspiration of occluded hemodialysis grafts with a Desilets-Hoffman Sheath is an effective and safe method.

Computational Fluid Dynamics of Intracranial and Extracranal Arteries using 3-Dimensional Angiography: Technical Considerations with Physician's Point of View.

We investigate the potentials and limitations of computational fluid dynamics (CFD) analysis of patient specific models from 3D angiographies. There are many technical problems in acquisition of proper vascular models, in pre-processing for making 2D surface and 3D volume meshes and also in post-processing steps for display the CFD analysis. We hope that our study could serves as a technical reference to validating other tools and CFD results.

Computational flow dynamics of the severe m1 stenosis before and after stenting.

PURPOSE: Computational flow dynamic (CFD) study has not been widely applied in intracranial artery stenosis due to requirement of high resolution in identifying the small intracranial artery. We described a process in CFD study applied to symptomatic severe intracranial (M1) stenosis before and after stenting. MATERIALS AND METHODS: Reconstructed 3D angiography in STL format was transferred to Magics (Materialise NV, Leuven, Belgium) for smoothing of vessel surface and trimming of branch vessels and to HyperMesh (Altair Engineering Inc., Auckland, New Zealand) for generating tetra volume mesh from triangular surface-meshed 3D angiogram. Computational analysis of blood flow in the blood vessels was performed using the commercial finite element software ADINA Ver 8.5 (ADINA R & D, Inc., Lebanon, MA). The distribution of wall shear stress (WSS), peak velocity and pressure in a patient was analyzed before and after intracranial stenting. RESULTS: Computer simulation of wall shear stress, flow velocity and wall pressure before and after stenting could be demonstrated three dimensionally by video mode according to flow vs. time dimension. Such flow model was well correlated with angiographic finding related to maximum degree of stenosis. Change of WSS, peak velocity and pressure at the severe stenosis was demonstrated before and after stenting. There was no WSS after stenting in case without residual stenosis. CONCLUSION: Our study revealed that CFD analysis before and after intracranial stenting was feasible despite of limited vessel wall dimension and could reveal change of WSS as well as flow velocity and wall pressure.

High shear stress at the surface of enhancing plaque in the systolic phase is related to the symptom presentation of severe M1 stenosis.

The computational fluid dynamics methods for the limited flow rate and the small dimensions of an intracranial artery stenosis may help demonstrate the stroke mechanism in intracranial atherosclerosis. We have modeled the high wall shear stress (WSS) in a severe M1 stenosis. The high WSS in the systolic phase of the cardiac cycle was well-correlated with a thick fibrous cap atheroma with enhancement, as was determined using high-resolution plaque imaging techniques in a severe stenosis of the middle cerebral artery.

Tumor detection and serosal invasion of bladder cancer: role of three-dimensional volumetric reconstructed US.

BACKGROUND: Accurate evaluation of local extent in bladder cancer is important to determine the optimal therapeutic strategy and to predict the outcome of treatment. The purpose of this study is to evaluate the accuracy of 3D volumetric reconstructed US in the assessment of tumor detection and serosal invasion in patients with bladder cancer. METHODS: A total of 14 patients with findings of bladder cancer determined with the use of cystoscopy was examined with the use of bladder two-dimensional (2D) US and subsequent 3D US. US findings were compared with cystoscopy findings and the pathological stage after a TURB or a radical cystectomy in a double-blinded manner. RESULTS: The sensitivity of preoperative tumor staging was 67.9% for 2D US and sensitivity was 78.6% for 3D US. 3D US was superior sensitivity than 2D US (P < 0.05). The accuracy for serosal invasion in staging of bladder cancer was demonstrated for 88.9% in 2D US and for 100% in 3D US. CONCLUSIONS: The accuracy for serosal invasion (T3b) in the staging of bladder cancer was demonstrated for 88.9% in 2D US and for 100% in 3D US. 3D volumetric reconstructed US is a non-invasive and accurate technique for tumor detection of bladder cancer.

Schwannomatosis involving peripheral nerves: a case report.

Schwannomatosis or neurilemmomatosis has been used to describe patients with multiple nonvestibular schwannomas with no other stigmata of neurofibromatosis type-2 (NF-2). In our case, schwannomatosis, multiple schwannomas were present in a 21-yr-old woman with no stigmata or family history of NF-1 or NF-2. She had no evidence of vestibular schwannoma or other intracranial tumors. Multiple peripheral tumors were found in the carotid space of the neck, and soft tissue of posterior shoulder, lower back, ankle and middle mediastinum. All of those tumors were completely limited to the right side of the body. All surgically removed tumor specimens in this patient proved to be schwannomas.

Pattern of atherosclerotic carotid stenosis in Korean patients with stroke: different involvement of intracranial versus extracranial vessels.

BACKGROUND AND PURPOSE: The clinical pattern of stroke and the angiographic distribution of cerebral atherosclerosis in the Japanese and Chinese are different from those in whites. Our purpose was to evaluate the location and distribution of severe atherosclerotic stenoses in Korean patients by using cerebral angiography. METHODS: We retrospectively reviewed the cerebral angiographic findings in 268 patients (219 male, 49 female; mean age, 56 years) with one or more severe atherosclerotic stenoses (> or =70%), as shown on angiograms. These patients were selected from 1436 patients who were examined between 1996 and 1997. The analysis focused on the intracranial or extracranial location of the stenosis, the anterior and posterior circulations, and the multiplicity of the lesions. Statistical analysis was performed by using the chi(2) test. The data were then compared with data reported in other races and ethnic groups. RESULTS: A total of 389 severe stenotic sites were detected in 268 patients. A single stenosis was found in 56 (21%), and multiple stenoses were found in 212 (79%). Lesions were located in the intracranial area in 52% and in the extracranial area in 48%. They were detected in anterior circulation in 59% and in posterior circulation in 41%. Thirty-seven (66%) of 56 single stenosis were located in the intracranial area, and 19 (34%) were in the extracranial area. Of 333 lesions, 167 (50%) were multiple stenoses in the extracranial area, and 166 lesions (50%) were located in the intracranial vessels. The prevalence of intracranial stenosis was significantly higher in the single-stenosis group than in the multiple stenosis group (P <.05). CONCLUSION: Korean patients with severe atherosclerotic stenoses tend to have more intracranial stenoses. In particular, those with an isolated stenosis have more intracranial stenoses, compared with those with multiple stenoses.