Wedging of vertebral bodies at the thoracolumbar spine in healthy individuals on whole body MRI screening: correlation with disc degeneration and disc herniation.

BACKGROUND: There have been no reports on the relationship between wedging of vertebral bodies at the thoracolumbar spine and disc herniation in healthy individuals on magnetic resonance imaging (MRI). PURPOSE: To investigate the degree of wedging of vertebral bodies at the thoracolumbar spine in healthy individuals who underwent whole-body (WB) MRI. We also assessed the correlation between wedging and adjacent disc pathology. MATERIAL AND METHODS: This retrospective study comprised 200 healthy patients who underwent WB MRI as part of a regular health check from January 2019 to February 2019. We measured anterior and posterior vertical heights of each vertebral body between T10 and L2. The ratio of anterior height to posterior height (APR) was calculated, and we evaluated disc degeneration or disc herniation using WB MRI. RESULTS: The APR of T10 was significantly higher than at the other levels (P < 0.05), and the APR of L1 was significantly lower (P < 0.05). Men had a significantly smaller APR than women at T12 to L2 (P < 0.05). Regarding the relationship between APR and disc degeneration, the group without disc degeneration had a higher APR, with statistical significance at T12, L1, and L2. Regarding the relationship between APR and disc herniation, the group without disc herniation had a higher APR, with statistical significance at T11, T12, L1, and L2. CONCLUSION: Wedging of vertebral bodies is most prominent at L1. Although the values were statistically significant only at some levels, the patients with disc degeneration or herniation had more prominent wedge deformity of thoracolumbar spine.

Prospective Multicenter Study of the Safety of Gadoteridol in 6163 Patients.

BACKGROUND: The safety of gadolinium-based contrast agents is of fundamental importance. PURPOSE: To determine the frequency and severity of immediate-type adverse reactions to approved doses of gadoteridol in patients referred for routine gadoteridol-enhanced MRI in actual clinical practice settings. STUDY TYPE: Prospective, observational. POPULATION: In all, 6163 subjects were enrolled (mean age: 56.7 ± 15.4 years; range: 6-93 years). FIELD STRENGTH/SEQUENCE: 1.5T and 3.0T. ASSESSMENT: Assessment was of immediate adverse reactions by the investigating radiologist using the MedDRA System Organ Class and preferred term. STATISTICAL TESTS: Summary statistics for continuous variables, descriptive statistics for demographic characteristics. RESULTS: Overall, 19 adverse events occurred in 13 (0.21%) patients, of which 15 in 10 (0.16%) patients were considered related to gadoteridol administration. These events were evenly distributed between male and female subjects and all occurred in adults. Twelve of the 15 related events in eight (0.13%) patients were considered mild in intensity (rapidly self-resolving), while the remaining three events in two patients (0.03%) were considered moderate in intensity. None were of severe intensity and no serious adverse events occurred. DATA CONCLUSION: The rate of immediate-type adverse events following exposure to approved doses of gadoteridol is extremely low, and mostly limited to transient and self-resolving symptoms. LEVEL OF EVIDENCE: 2 Technical Efficacy Stage: 5 J. Magn. Reson. Imaging 2020;51:861-868.

Usefulness of the quantitative evaluation of diffusion-weighted mri in the diagnosis of anterior cruciate ligament tears.

PURPOSE: To evaluate the usefulness of the diffusion-weighted imaging (DWI) in the diagnosis of anterior cruciate ligament (ACL) tear using the contrast-to-noise ratio (CNR) and apparent diffusion coefficient (ADC) values according to the different b values. MATERIALS AND METHODS: Institutional review board approval was acquired. We evaluated 74 patients (M:F = 43:31, mean age of 44 years) who underwent 3.0 Tesla knee MR with DWI because of the possibility of ACL tear due to trauma. Region of interest measurements were performed. We (two radiologists) measured the signals of the DWI and derived ADC values on the oblique sagittal DWI with b values of 0, 600, and 1000. The diagnostic accuracies of the conventional MR image and each DWI with an ADC value with a different b value were evaluated. The CNR and ADC values were compared using the Mann-Whitney U-test. The diagnostic performances of the various imaging methods were evaluated using the sensitivity, specificity, and accuracy for differentiating between normal and ACL injury as determined by the use of conventional MRI with additional DWIs with McNemar test. The arthroscopic or clinical findings were used as the reference standard. RESULTS: The mean CNRs of ligament tears with b values of 600 and 1000 were significantly higher than those of normal ligament (22 versus 7 and 9 versus 4, P value < 0.05). The sensitivities and the accuracies of the DWI were significantly lower than the conventional MRIs (P value < 0.001). CONCLUSIONS: The CNRs of the torn ACL with each b value (600 and 1000) were significantly higher those of than normal ligament, although the ADC values of the torn ligament were not different from normal ligament. Addition of the DWI to the conventional MRI did not improve diagnostic performance. J. Magn. Reson. Imaging 2016;44:1116-1122.

Modified thoracolumbar injury classification and severity score (TLICS) and its clinical usefulness.

BACKGROUND: Thoracolumbar injury classification and severity score (TLICS) is not very reliable for assessment of injury to the posterior ligament complex, even when scored by experts. It is not reasonable to score every compression fracture or burst fracture the same as there is great variety in the severity of compression fractures and burst fractures. PURPOSE: To propose a modified TLICS (mTLICS) and evaluate the performance of the mTLICS system by measuring the agreement between scores determined by radiologists using both systems and actual treatment procedure delivered. MATERIAL AND METHODS: We retrospectively evaluated 134 patients with acute lumbar and thoracic spinal trauma after undergoing magnetic resonance imaging (MRI) using new mTLICS and conventional TLICS system. Inter-observer agreements of TLICS and mTLICS scores were analyzed using the kappa statistic. Nonparametric correlation analysis was used to determine correlation (R) among each score and the surgical intervention. RESULTS: The mTLICS system showed slightly higher correlation than TLICS (Rs, TLICS, 0.592 and 0.613 vs. mTLICS, 0.628 and 0.639). If we consider a total maximal score of 4 to be a negative surgical indication, mTLICS showed significantly higher sensitivities than TLICS, and if we consider a total minimal score of 4 to be a positive surgical indication, mTLICS showed significantly higher specificities than TLICS. CONCLUSION: The mTLICS score corrects deficiencies in the TLICS system that lead to ambiguity in the radiological diagnostic criteria. mTLICS is a more suitable scoring system than TLICS for predicting surgical management accurately, especially for morphological injuries.

Differential Diagnosis of Chronic Total Occlusive and Subtotal Occlusive Disease of the Lower Extremity Arteries Using Reverse Attenuation Gradient Sign on CT Angiography.

OBJECTIVE: The purpose of this study is to evaluate the diagnostic usefulness of the reverse attenuation gradient sign in occlusive lower extremity arterial disease through CT angiography (CTA). MATERIALS AND METHODS: This study sample enrolled 45 men and eight women in the chronic total occlusion group and 30 men and seven women in the subtotal occlusion group. Luminal CT attenuation (in Hounsfield units) was measured at three points from the end of the occlusion site to the first collateral vessel's insertion point. We also used Hounsfield units to measure the CT attenuation of the opposite side artery at the same level in a similar manner. We compared each value using the Mann-Whitney U test. RESULTS: The absolute value of the mean differences in the Hounsfield units among the proximal, middle, and distal portion of chronic total occlusions were higher than those of subtotal occlusions, and this result was statistically significant (p < 0.001). The mean ratios of the Hounsfield units (Hounsfield units of the stenosed lumen divided by Hounsfield units of the opposite normal lumen) of the proximal portion of chronic total occlusions were statistically significantly lower than those of subtotal occlusions. CONCLUSION: The reverse attenuation gradient sign can be applied to the lower extremity arteries and can be helpful for differential diagnosis of chronic total occlusions from subtotal occlusions using CTA.

IDEAL 3D spoiled gradient echo of the articular cartilage of the knee on 3.0 T MRI: a comparison with conventional 3.0 T fast spin-echo T2 fat saturation image.

BACKGROUND: Many two-dimensional (2D) morphologic cartilage imaging sequences have disadvantages such as long acquisition time, inadequate spatial resolution, suboptimal tissue contrast, and image degradation secondary to artifacts. IDEAL imaging can overcome these disadvantages. PURPOSE: To compare sound-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and quality of two different methods of imaging that include IDEAL 3D SPGR and 3.0-T FSE T2 fat saturation (FS) imaging and to evaluate the utility of IDEAL 3D SPGR for knee joint imaging. MATERIAL AND METHODS: SNR and CNR of the patellar and femoral cartilages were measured and calculated. Two radiologists performed subjective scoring of all images for three measures: general image quality, FS, and cartilage evaluation. SNR and CNR values were compared by paired Student's t-tests. RESULTS: Mean SNRs of patellar and femoral cartilages were 90% and 66% higher, respectively, for IDEAL 3D SPGR. CNRs of patellar cartilages and joint fluids were 2.4 times higher for FSE T2 FS, and CNR between the femoral cartilage and joint fluid was 2.2 times higher for FSE T2 FS. General image quality and FS were superior using FSE T2 FS compared to those of IDEAL 3D SPGR imaging according to both readers, while cartilage evaluation was superior using IDEAL 3D SPGR. Additionally, cartilage injuries were more prominent in IDEAL 3D SPGR than in FSE T2FS according to both readers. CONCLUSION: IDEAL 3D SPGR images show excellent visualization of patellar and femoral cartilages in 3.0 T and can compensate for the weaknesses of FSE T2 FS in the evaluation of cartilage injuries.

Clinical correlation of a new and practical magnetic resonance grading system for cervical foraminal stenosis assessment.

BACKGROUND: No systematic and quantitative system for evaluation of cervical neural foraminal stenosis (CNFS) has been reported. PURPOSE: To evaluate whether the new magnetic resonance (MR) grading system for CNFS correlates with clinical manifestations and to propose a modified grading system more useful for clinical practice. MATERIAL AND METHODS: We examined 356 patients who underwent MR imaging (MRI) of the cervical spine. The presence and grade of cervical foraminal stenosis at the maximal narrowing point were assessed using the new grading system suggested by Kim et al. (Kim system) and a modification of this grading system (modified Kim system) based on T2 axial images. Grade 0: narrowest neural foramen > extraforaminal root; Grade 1: ≤ extraforaminal root; Grade 2: <50% of extraforaminal root. Modified Kim system: Grade 0: >80%, Grade 1: <80% but >50%, Grade 2 as for the Kim system. Results were correlated with clinical manifestations and neurologic physical examination findings (positive neurologic manifestation [PNM]). RESULTS: Analysis of correlation coefficients (Rs) showed moderate correlation between grades and clinical manifestations using the Kim system (0.484-0.562) and moderate to high correlation between grades and PNMs using the modified Kim system (0.517-0.782). CONCLUSION: The Kim system showed moderate correlation clinical findings, while the modified Kim system still showed moderate but slightly stronger correlation. In both systems, grade 0 could denote negative neurologic manifestations. Although a considerable number of grade 1 and 2 cases in both systems had PNM, fulfilling the criteria for grades 1 and 2 CNFS, it does not perfectly predict PNM.

The usefulness of the oblique coronal plane in knee MRI on the evaluation of the posterior cruciate ligament.

BACKGROUND: Imaging findings of posterior cruciate ligament (PCL) injury may be equivocal, particularly when the patient has suffered a partial ligament tear. Some PCLs are positioned more horizontally, making it difficult to diagnose injury based on routine imaging planes alone due to partial volume artifact. PURPOSE: To evaluate the diagnostic accuracy of combining oblique coronal imaging (PCL view) with traditional orthogonal views for PCL evaluation. MATERIAL AND METHODS: This retrospective study included 20 patients with PCL injury and 43 patients with intact PCL who underwent PCL view imaging. Anatomic identification of PCL pathology on the orthogonal magnetic resonance imaging (MRI) sequences and PCL views was evaluated. Subjective scoring of the PCL was performed by two radiologists who assessed the possibility of a PCL tear based on an entire length view, an entire width view, and margin sharpness according to a 4-point scale. Diagnostic accuracy using these two views was evaluated by calculating the sensitivity, specificity, and accuracy. Arthroscopic and clinical findings were used as the reference standard. RESULTS: Total scores for the PCL view were higher than those of orthogonal views (P < 0.001). Both readers found that anatomic identification using the full width view and sharp margin to be superior using the PCL view compared with the orthogonal views (P < 0.001). The specificities and accuracies were higher in cases where an additional PCL view was provided, but did not show statistical significance. CONCLUSION: PCL view provides better anatomic evaluation of the PCL and mild improvement in the specificity and accuracy.

A new assessment of patellar instability using coronal magnetic resonance images of the patella superimposed on the femur and its clinical utility.

OBJECTIVE: This study aimed to evaluate the clinical utility of a new assessment for patellar subluxation using magnetic resonance (MR) images of the patella superimposed on the femur and to determine its correlation with the tibial tuberosity-trochlear groove (TT-TG) distance. MATERIALS AND METHODS: This retrospective study included 81 men and 44 women who underwent MR imaging at our institution. There were 19 cases of patellar dislocation. The control group consisted of 116 patients. An assessment of the distance of subluxation was carried out using coronal superimposed MR images. The results were correlated with the TT-TG distance calculated using the axial combined MR images. The sensitivity and specificity of various distances of subluxation were evaluated as diagnostic thresholds for patellar dislocation, where the clinical diagnosis was used as the standard of reference. RESULTS: The use of the distance of subluxation on coronal superimposed MR images showed discrete difference between patellar dislocation and controls. The mean distance of subluxation was approximately 3 times larger for patients with patellar dislocation compared with controls (P < 0.001). Likewise, the mean TT-TG distance was approximately 50% greater for patients with patellar dislocation compared with controls (P < 0.001). However, there was no correlation between the distance of subluxation and the TT-TG distance. The best diagnostic discrimination was achieved at the 7-mm threshold of subluxation. CONCLUSIONS: The use of the distance of subluxation on coronal superimposed MR images can be a useful method to evaluate patellar dislocation. The best diagnostic discrimination was achieved at a threshold of 7 mm.

Various techniques of stent-assisted coil embolization of wide-necked or fusiform artherosclerotic and dissecting unruptured vertebrobasilar artery aneurysms for reducing recanalization: mid-term results.

BACKGROUND: Coil embolization of wide-necked or fusiform vertebrobasilar aneurysms is challenging and tends to involve frequent recanalization. PURPOSE: The aim of our study was to evaluate complications and mid-term outcomes of complex vertebrobasilar artery aneurysms after stent-assisted coiling with various techniques. METHODS: We retrospectively evaluated 28 cases of unruptured vertebrobasilar aneurysm treated by stent-assisted coiling. RESULTS: Forty-four of the 45 stents placed in 28 patients were deployed at the desired location (97.8 %). Single stent-assisted coiling was performed in 14 aneurysms, a stent-within-a-stent (SWS) technique was used in 12 aneurysms, and Y-stent-assisted coiling was employed in four basilar tip aneurysms. Two basilar tip aneurysms treated by single stent-assisted coiling recurred and were retreated by SWS and Y-stent-assisted coiling. Complete embolization was achieved in 19 aneurysms (67.8 %), and remnant neck persisted in eight aneurysms (28.6 %) and remnant aneurysm was noted in one aneurysm (3.6 %). Permanent neurologic deficit (Modified Rankin Scale 1 and 4) was noted in two patients (7.1 %). Angiographic follow-up (mean follow-up period: 20.8 months) was performed in 20 patients. Major recanalization occurred in two basilar tip aneurysms (10 %) and minor compaction was noted in one superior cerebellar artery aneurysm. The remaining 17 aneurysms were stable or improved (85 %). CONCLUSIONS: Complex vertebrobasilar aneurysm embolization with stent-assisted techniques was effective and feasible as a method for reducing recanalization during midterm angiographic follow-up. Large and wide-necked basilar tip aneurysms showed frequent major recanalization, and compact packing with single or Y-stent-assisted coiling is needed to prevent recanalization even if coiling will be done without stenting.

Disconnection-Based Prediction of Poststroke Dysphagia.

BACKGROUND AND PURPOSE: Dysphagia is a common deficit after a stroke and is associated with serious complications. It is not yet fully clear which brain regions are directly related to swallowing. Previous lesion symptom mapping studies may have overlooked structural disconnections that could be responsible for poststroke dysphagia. Here, we aimed to predict and explain the relationship between poststroke dysphagia and the topologic distribution of structural disconnection via a multivariate predictive framework. MATERIALS AND METHODS: We enrolled first-ever ischemic stroke patients classified as full per-oral nutrition (71 patients) and nonoral nutrition necessary (43 patients). After propensity score matching, 43 patients for each group were enrolled (full per-oral nutrition group with 17 women, 68 ± 15 years; nonoral nutrition necessary group with 13 women, 75 ± 11 years). The structural disconnectome was estimated by using the lesion segmented from acute phase diffusion-weighted images. The prediction of poststroke dysphagia by using the structural disconnectome and demographics was performed in a leave-one-out manner. RESULTS: Using both direct and indirect disconnection matrices of the motor network, the disconnectome-based prediction model could predict poststroke dysphagia above the level of chance (accuracy = 68.6%, permutation P = .001). When combined with demographic data, the classification accuracy reached 72.1%. The edges connecting the right insula and left motor strip were the most informative in prediction. CONCLUSIONS: Poststroke dysphagia could be predicted by using the structural disconnectome derived from acute phase diffusion-weighted images. Specifically, the direct and indirect disconnection within the motor network was the most informative in predicting poststroke dysphagia.

Preprocedural determination of an occlusion pathomechanism in endovascular treatment of acute stroke: a machine learning-based decision.

OBJECTIVE: To evaluate whether an occlusion pathomechanism can be accurately determined by common preprocedural findings through a machine learning-based prediction model (ML-PM). METHODS: A total of 476 patients with acute stroke who underwent endovascular treatment were retrospectively included to derive an ML-PM. For external validation, 152 patients from another tertiary stroke center were additionally included. An ML algorithm was trained to classify an occlusion pathomechanism into embolic or intracranial atherosclerosis. Various common preprocedural findings were entered into the model. Model performance was evaluated based on accuracy and area under the receiver operating characteristic curve (AUC). For practical utility, a decision flowchart was devised from an ML-PM with a few key preprocedural findings. Accuracy of the decision flowchart was validated internally and externally. RESULTS: An ML-PM could determine an occlusion pathomechanism with an accuracy of 96.9% (AUC=0.95). In the model, CT angiography-determined occlusion type, atrial fibrillation, hyperdense artery sign, and occlusion location were top-ranked contributors. With these four findings only, an ML-PM had an accuracy of 93.8% (AUC=0.92). With a decision flowchart, an occlusion pathomechanism could be determined with an accuracy of 91.2% for the study cohort and 94.7% for the external validation cohort. The decision flowchart was more accurate than single preprocedural findings for determining an occlusion pathomechanism. CONCLUSIONS: An ML-PM could accurately determine an occlusion pathomechanism with common preprocedural findings. A decision flowchart consisting of the four most influential findings was clinically applicable and superior to single common preprocedural findings for determining an occlusion pathomechanism.

Clinical correlation of a new practical MRI method for assessing cervical spinal canal compression.

OBJECTIVE: The purpose of this study was to evaluate interobserver agreement and whether or not a new MRI grading system correlates with symptoms and neurologic signs for assessing spinal canal compression. MATERIALS AND METHODS: One hundred patients (52 men and 48 women; mean age, 50 years) underwent MRI of the cervical spine at our institution and were evaluated by two musculoskeletal radiologists. The presence and grade of cervical canal stenosis at the maximal narrowing point was assessed according to the new grading system suggested by Kang et al. (Kang system). The results correlated with the clinical manifestations and neurologic examination. Statistical analysis was performed using kappa statistics, categoric regression analysis, and nonparametric correlation analysis (Spearman correlation). RESULTS: Interobserver agreement in the grading of spinal stenosis between the two readers was almost perfect (κ = 0.925). Most of the patients with grade 0 cervical canal stenosis showed no neurologic manifestation, and patients with grades 2 and 3 cervical canal stenosis had positive neurologic manifestations. The correlation coefficient (R) of reader 1 between MRI grade (0, 1, 2, and 3) and neurologic manifestations (positive or negative) was 0.846. The R of reader 2 was 0.808. In the younger age group (< 50 years old), the R of reader 1 was 0.834 and the R of reader 2 was 0.745. In the older age group (≥ 50 years old), the R of reader 1 was 0.839 and the R of reader 2 was 0.839. CONCLUSION: The interobserver agreement of the Kang system was almost perfect and was higher than in the study by Kang et al. Grade 0 cervical canal stenosis represents negative neurologic manifestations and grades 2 and 3 cervical canal stenosis represent positive neurologic manifestations. The Kang system and clinical manifestations are significantly correlated, especially in the older age group (≥ 50 years).

Accuracy of MR findings in characterizing peroneal tendons disorders in comparison with surgery.

BACKGROUND: Previous studies have shown that magnetic resonance imaging (MRI) has a high sensitivity for peroneal tendon pathology but more studies with surgery as a reference standard are needed. PURPOSE: To evaluate the accuracy of MRI compared to surgery for characterizing chronic peroneal tendon pathology. MATERIAL AND METHODS: Ninety-seven patients (57 men, 40 women; mean age, 39 years; range, 15-64 years) with chronic lateral ankle instability underwent MRI followed by surgery, with a mean MR to surgery interval of 30 days. Sagittal, coronal, and axial T1-weighted spin-echo and fat-suppressed T2-weighted fast spin-echo images were obtained for all patients. Two blinded observers evaluated the MR images without clinical information, and the results were compared to surgical findings. The following peroneal injuries were observed: tendon split, interstitial tear, swelling of the tendon, fluid collection, superior peroneal retinaculum injury, and tendon dislocation. RESULTS: Swelling of the peroneus longus tendon was the most common finding on MR imaging, followed by fluid collection and a split of the peroneus brevis tendon. Surgical findings showed that nine cases (9%) of interstitial tears were in the peroneus brevis and two cases (2%) were in the peroneus longus, with eight cases (8%) of splits in the peroneus brevis tendon. The sensitivity and specificity for detecting interstitial tears in the peroneus brevis were 44% and 99%, respectively. The sensitivity and specificity for detecting swelling in the peroneus brevis were 50% and 99%, respectively. The sensitivity and specificity for detecting interstitial tears for peroneus longus injuries were 50% and 96%, respectively. The sensitivity and specificity for detecting swelling in these injuries were and 100% and 96%, respectively. CONCLUSION: MRI findings of chronic peroneal tendon pathology are diagnostically specific but not sensitive. MRI showed high sensitivity for diagnosing tendon swelling in the peroneus longus, but not in the peroneus brevis. MRI is sensitive but not specific for detecting negative findings.

Sonographic appearances of soft tissue angioleiomyomas: differences from other circumscribed soft tissue hypervascular tumors.

OBJECTIVES: The purpose of this study was to evaluate the sonographic features of angioleiomyomas with priority given to the vascular pattern to help in the differential diagnosis from other hypervascular soft tissue tumors. METHODS: The inclusion criteria for this retrospective and nonblinded study were fulfilled in 33 patients with circumscribed hypervascular soft tissue tumors based on pathologic identification. Thirteen cases were angioleiomyomas; 9 cases were nonsubungual glomus tumors; and 11 cases were hemangiomas. Two musculoskeletal radiologists interpreted the results by consensus. Sonographic findings, including the shape, size, echogenicity, vascular pattern, and vascular density of the angioleiomyomas, were compared with those of the other hypervascular tumors. Vascular patterns were categorized into 3 vascular types: 1, several linear vessels clustered in the tumor with convergence to one point; 2, diffusely scattered irregular vessels in the tumor, and 3, one or more vessels that were centrally located. The vascularity of the mass was also categorized as rich (covering >50% of the area of the lesion), moderate (between 20% and 50%), and little (<20%). RESULTS: All of the angioleiomyomas were hypoechoic (100% [13 of 13]), a statistically significant result (P = .001). The type 1 vascular pattern was observed in 69% of the angioleiomyomas (9 of 13; P = .029), and the statistically significant shape was round (38% [5 of 13]; P = .035). CONCLUSIONS: Most angioleiomyomas reveal a homogeneously hypoechoic echo texture with a circumscribed margin and show straight and linear vessels in the tumor with convergence to one point on color Doppler sonography. These characteristics may be helpful when differentiating angioleiomyomas from other circumscribed hypervascular soft tissue tumors.

Hyperattenuations on flat-panel computed tomography after successful recanalization of mechanical thrombectomy for anterior circulation occlusion.

BACKGROUND: To evaluate intraparenchymal hyperattenuation (IPH) on flat-panel computed tomography (FPCT) findings and their clinical usefulness for predicting prognosis after successful mechanical thrombectomy (MT) for acute occlusion of anterior circulation. METHODS: A retrospective review was conducted for 158 consecutive patients undergoing mechanical thrombectomy during the last six years. After excluding those with posterior circulation occlusion or incomplete recanalization and those without FPCT, 82 patients were finally included. Immediate post-procedural IPH on FPCT was categorized into four patterns (none, striatal, cortical, or combined pattern). Follow-up magnetic resonance images or CT scans after 48 hours from MT were analyzed according to FPCT findings. The existence of hemorrhagic transformation, intracerebral hemorrhage, and brain swelling was evaluated. Functional clinical outcomes were accessed with post-procedural 3-month modified Rankin scales (mRS). RESULTS: Of 82 patients, 34 patients were found to have IPH (16 with a striatal pattern, 8 with a cortical pattern, and 10 with a combined pattern). Hemorrhagic complication (P<0.001), brain swelling (P<0.001), and poor mRS scores (P=0.042) showed significant differences according to IPH patterns. Multivariate logistic regression analysis revealed that the presence of a striatal pattern (OR: 13.26, P<0.001), cortical pattern (OR: 11.61, P=0.009), and combined pattern (OR: 45.34, P<0.001) independently predicted hemorrhagic complications. The location of the occlusion (OR: 4.13, P=0.034), cortical pattern (OR: 5.94, P=0.039), and combined pattern (OR: 39.85, P=0.001) predicted brain swelling. Age (OR: 1.07, P=0.006) and the presence of a combined pattern (OR: 10.58, P=0.046) predicted poor clinical outcomes. CONCLUSIONS: FPCT is a rapid and effective tool for a prompt follow-up just after MT to predict prognosis. Those with striatal patterns showed relatively good clinical outcomes despite significant hemorrhage. Cortical IPH patterns independently predicted a high rate of post-procedural hemorrhage or brain swelling. Combined pattern is a strong predictor for both radiologic and poor clinical outcomes.

Incidental findings of the lumbar spine at MRI during herniated intervertebral disk disease evaluation.

OBJECTIVE: The objective of our study was to evaluate the frequency and types of incidental findings of the lumbar spine during MR evaluation for herniated intervertebral disk disease. MATERIALS AND METHODS: A total of 1268 patients (male-to-female ratio, 421:847; age range, 1-97 years) with clinically suspected herniated intervertebral disk disease underwent MRI of the lumbar spine. Musculoskeletal radiologists evaluated the MR examinations for the presence of incidental findings. We defined incidental finding as any abnormal finding not related to the chief complaint. Vertebral hemangioma, Tarlov cyst, fibrolipoma, synovial cyst, and sacral meningocele were included. Frequency distributions of the assessed imaging characteristics were calculated. For analysis of the relationship of incidental findings with patient characteristics, the chi-square test was used. RESULTS: Overall, 107 patients (8.4%) had incidental findings. Fibrolipoma was most common (41 cases, 3.2%), followed by Tarlov cyst (27 cases, 2.1%) and vertebral hemangioma (19 cases, 1.5%). Fibrolipoma and sacral meningocele were more common in males (p < 0.05). There was no difference in the incidence between the sexes in the other incidental findings (p = 0.26-0.96). Four of the five incidental findings were significantly more frequent in individuals younger than 50 years (p < 0.05), whereas the incidence of vertebral hemangioma did not differ by patient age (p = 0.32). CONCLUSION: Incidental findings at MRI of the lumbar spine were common and associated with age and sex. Most were benign findings. An awareness of the prevalence of the incidental findings detected at MRI of the lumbar spine is helpful for diagnosing lesions not related to symptoms.

Gray-scale and color Doppler sonographic appearances of nonsubungual soft-tissue glomus tumors.

BACKGROUND: To evaluate the sonographic findings of soft-tissue nonsubungual glomus tumors. METHODS: The sonographic appearances of nine histologically proven soft-tissue glomus tumors of nonsubungual location in nine patients (mean age, 49 years; M:F = 7:2) were reviewed retrospectively. Doppler examination and surgical excision were performed in all cases. RESULTS: The mean size of the lesions was 1 cm. The margins of the lesions were relatively well-circumscribed in eight of nine patients (89%) with an ovoid shape in seven of nine patients (78%). The vascularity was moderate to rich in all cases, with an arterial flow pattern but no arteriovenous shunt patterns. The "vascular stalk sign" was noted in six cases (67%). CONCLUSIONS: Nonsubungual glomus tumors are rare soft-tissue tumors with abundant vascularity and arterial flow pattern.

Ultrasound and MRI findings as predictors of propranolol therapy response in patients with infantile hemangioma.

OBJECTIVES: To evaluate the prognostic value of ultrasound and MRI findings in patients with infantile hemangioma undergoing propranolol therapy. METHODS: This study was based on retrospective interpretation of prospectively acquired data. Thirty-eight consecutive patients (28 females and 10 males; mean age ± standard deviation, 3.2 ± 2.2 months) who underwent propranolol treatment for infantile hemangioma were included. Pre-treatment ultrasound images were assessed in terms of echogenicity, lesion height and vascularity. Presence of prominent intratumoral fat, non-fat septa, and enhancement pattern on MRI were retrospectively evaluated. Mann-Whitney test, chi-square, and Fisher's exact tests were used to compare imaging parameters between patients with treatment success and failure. RESULTS: All patients underwent ultrasound and 15 patients underwent MRI. A total of 24 patients showed successful treatment. Between patients with treatment success and failure, there were significant differences in increased vascularity on pre-treatment ultrasound (19/24 vs. 6/14, p = 0.025), decreased vascularity on post-treatment ultrasound (21/24 vs. 5/14, p = 0.001), and prominent intratumoral fat on MRI (1/8 vs. 5/7 p = 0.033). There were no significant differences in echogenicity, lesion height on ultrasound, non-fat septa and MR enhancement pattern. CONCLUSIONS: Increased vascularity on pre-treatment ultrasound was significantly associated with successful treatment for propranolol therapy in patients with infantile hemangioma, whereas prominent fat component on MRI was significantly associated with treatment failure.

Massive Cerebral Microemboli after Protected Carotid Artery Angioplasty and Stenting Using a Distal Filter Embolic Protection Device for a Vulnerable Plaque with a Lipid Rich Necrotic Core and Intraplaque Hemorrhage: A Case Report.

A major concern associated with carotid artery angioplasty and stenting (CAS) is a periprocedural distal cerebral embolization. To prevent distal embolization, embolic protection devices (EPDs) have been developed. However, the risk of cerebral embolism after protected CAS in patents with a vulnerable plaque is controversial and either a silent or a symptomatic stroke can occur despite the use of EPDs. Here, we report a case of a massive cerebral microemboli after a protected CAS using a distal filter EPD for a vulnerable plaque with a lipid rich necrotic core and intraplaque hemorrhage.