Advantages of 3D High-Resolution Vessel Wall Imaging in a Patient With Blood Blister-Like Aneurysm: A Case Report and Literature Review.

Blood blister-like aneurysms (BBAs) are rare and challenging intracranial aneurysms. They pose significant diagnostic and surgical risks due to their delicate walls. Accounting for a small percentage of intracranial aneurysms, BBAs are pathologically pseudoaneurysms, often resulting from arterial dissection, with a high tendency to rupture. This report underscores the critical nature of BBAs by reviewing a case in which subarachnoid hemorrhage caused by a BBA rupture was difficult to diagnose with conventional imaging. We highlight the efficacy of three-dimensional (3D) high-resolution vessel wall imaging (VWI) in discerning the subtle vascular abnormality of BBAs. The integration of the black-blood imaging technique within VWI provides superior contrast between the aneurysm and surrounding tissues, facilitating clearer visualization of the aneurysmal wall. The use of 3D T1-weighted imaging provides intricate details of the vessel wall including its contrast enhancement, which is crucial for a comprehensive assessment of a ruptured aneurysm. This case is consistent with the existing literature, supporting the role of VWI in the identification of ruptured BBAs, an area with limited but growing information on its diagnostic value. VWI is precise and accurate in the preoperative diagnosis of BBAs, emphasizing its potential to improve patient management and outcomes, especially in conditions with high risks of morbidity and mortality.

Brain volume measured by synthetic magnetic resonance imaging in adult moyamoya disease correlates with cerebral blood flow and brain function.

Moyamoya disease (MMD) is characterized by progressive arterial occlusion, causing chronic hemodynamic impairment, which can reduce brain volume. A novel quantitative technique, synthetic magnetic resonance imaging (SyMRI), can evaluate brain volume. This study aimed to investigate whether brain volume measured with SyMRI correlated with cerebral blood flow (CBF) and brain function in adult MMD. In this retrospective study, 18 adult patients with MMD were included. CBF was measured using iodine-123-N-isopropyl-p-iodoamphetamine single photon emission computed tomography. Cerebrovascular reactivity (CVR) to acetazolamide challenge was also evaluated. Brain function was measured using the Wechsler Adult Intelligence Scales (WAIS)-III/IV and the WAIS-R tests. Gray matter (GM), white matter, and myelin-correlated volumes were evaluated in six areas. Resting CBF was positively correlated with GM fractions in the right anterior cerebral arterial and right middle cerebral arterial (MCA) territories. CVR was positively correlated with GM fraction in the right posterior cerebral arterial (PCA) territory. Full-Scale Intelligence Quotient and Verbal Comprehension Index scores were marginally positively correlated with GM fractions in the left PCA territory. Processing Speed Index score was marginally positively correlated with GM fraction in the right MCA territory. The SyMRI-measured territorial GM fraction correlated with CBF and brain function in patients with MMD.

Safety and clinical contribution of computed tomography-guided biopsy for cervical spine lesion.

INTRODUCTION: The purpose is to clarify the safety and clinical contribution of computed tomography (CT)-guided percutaneous needle-biopsy for patients with cervical spine lesion. MATERIAL AND METHODS: Between June 2015 and August 2022, CT-guided percutaneous needle biopsies were performed for 15 cervical spine lesions of 15 patients (8 male, 7 female; 2-81 years old). The technical success, clinical contribution, and safety were evaluated. Technical success was defined as the completion of the biopsy procedure. Clinical contribution was defined as any contribution to the therapeutic strategy. Safety was assessed by the Common Terminology Criteria for Adverse Events, version 5.0. RESULTS: The technical success rate was 100%. In all 15 patients, nontarget organs (e.g., major vessels, spinal cord) could be avoided. The post-biopsy histological diagnoses were myeloma (n = 2), metastatic adenocarcinoma (n = 2), chordoma (n = 2), Langerhans cell histiocytosis (n = 3), and one case each of malignant lymphoma, schwannoma, pyogenic spondylitis, non-pyogenic spondylitis, degenerative change, and non-pathological fracture. All of these diagnoses contributed to the therapeutic strategy decisions. One case of grade 2 pain was observed, but no complications with grade 3 or more were observed during or after the biopsies. CONCLUSION: CT-guided percutaneous needle biopsies for cervical spine lesions were safe and clinically beneficial.

Efficacy and safety of streptozocin-based chemotherapy for gastroenteropancreatic neuroendocrine tumors in Japanese clinical practice.

BACKGROUND: Streptozocin has been used to treat neuroendocrine tumors in Europe and the USA; however, its actual status in Japan has not been fully clarified owing to the rarity of this disease and the relatively recent approval of streptozocin in Japan. METHODS: We retrospectively analyzed 53 patients with gastroenteropancreatic neuroendocrine tumors who were treated with streptozocin-based chemotherapy at two Japanese hospitals between January 2004 and June 2023. RESULTS: The overall response and disease control rates were 27.7 and 74.5%, respectively, and the median progression-free survival and overall survival were 7.1 and 20.3 months, respectively. Performance status ≥1 showed a significant negative correlation with progression-free survival, and performance status ≥1 and liver tumor burden ≥25% showed a significant negative correlation with overall survival. No significant differences were observed in the treatment response between pancreatic and gastrointestinal neuroendocrine tumors. No treatment-related serious adverse events were observed; however, 87.7% of patients expressed a decrease in the estimated glomerular filtration rate, which negatively correlated with the duration of streptozocin treatment (r = 0.43, P = 0.0020). In the streptozocin re-administration group (n = 5), no differences were found in efficacy between the initial and second streptozocin treatments. CONCLUSIONS: Although streptozocin is a safe, streptozocin-induced renal dysfunction is a dilemma in streptozocin responders. Streptozocin may benefit patients with gastroenteropancreatic neuroendocrine tumors, especially those with a good performance status; however, in some cases, planned streptozocin withdrawal or switching to other drugs should be considered.

Improved temporal resolution and acceleration on 4D-MR angiography based on superselective pseudo-continuous arterial spin labeling combined with CENTRA-keyhole and view-sharing (4D-S-PACK) using an interpolation algorithm on the temporal axis and compressed sensing-sensitivity encoding (CS-SENSE).

PURPOSE: Two major drawbacks of 4D-MR angiography based on superselective pseudo-continuous arterial spin labeling combined with CENTRA-keyhole and view-sharing (4D-S-PACK) are the low temporal resolution and long scanning time. We investigated the feasibility of increasing the temporal resolution and accelerating the scanning time on 4D-S-PACK by using CS-SENSE and PhyZiodynamics, a novel image-processing program that interpolates images between phases to generate new phases and reduces image noise. METHODS: Seven healthy volunteers were scanned with a 3.0 T MR scanner to visualize the internal carotid artery (ICA) system. PhyZiodynamics is a novel image-processing that interpolates images between phases to generate new phases and reduces image noise, and by increasing temporal resolution using PhyZiodynamics, inflow dynamic data (reference) were acquired by changing the labeling durations (100-2000 msec, 31 phases) in 4D-S-PACK. From this set of data, we selected seven time intervals to calculate interpolated time points with up to 61 intervals using ×10 for the generation of interpolated phases with PhyZiodynamics. In the denoising process of PhyZiodynamics, we processed the none, low, medium, high noise reduction dataset images. The time intensity curve (TIC), the contrast-to-noise ratio (CNR) were evaluated. In accelerating with CS-SENSE for 4D-S-PACK, 4D-S-PACK were scanned different SENSE or CS-SENSE acceleration factors: SENSE3, CS3-6. Signal intensity (SI), CNR, were evaluated for accelerating the 4D-S-PACK. With regard to arterial vascular visualization, we evaluated the middle cerebral artery (MCA: M1-4 segments). RESULTS: In increasing temporal resolution, the TIC showed a similar trend between the reference dataset and the interpolated dataset. As the noise reduction weight increased, the CNR of the interpolated dataset were increased compared to that of the reference dataset. In accelerating 4D-S-PACK, the SI values of the SENSE3 dataset and CS dataset with CS3-6 were no significant differences. The image noise increased with the increase of acceleration factor, and the CNR decreased with the increase of acceleration factor. Significant differences in CNR were observed between acceleration factor of SENSE3 and CS6 for the M1-4 (P < 0.05). Visualization of small arteries (M4) became less reliable in CS5 or CS6 images. Significant differences were found for the scores of M2, M3 and M4 segments between SENSE3 and CS6. CONCLUSION: With PhyZiodynamics and CS-SENSE in 4D-S-PACK, we were able to shorten the scan time while improving the temporal resolution.

Multiparametric assessment of microvascular invasion in hepatocellular carcinoma using gadoxetic acid-enhanced MRI.

PURPOSE: To elucidate how precisely microvascular invasion (MVI) in hepatocellular carcinoma (HCC) can be predicted using multiparametric assessment of gadoxetic acid-enhanced MRI. METHODS: In this retrospective single-center study, patients who underwent liver resection or transplantation of HCC were evaluated. Data obtained in patients who underwent liver resection were used as the training set. Nine kinds of MR findings for predicting MVI were compared between HCCs with and without MVI by univariate analysis, followed by multiple logistic regression analysis. Using significant findings, a predictive formula for diagnosing MVI was obtained. The diagnostic performance of the formula was investigated in patients who underwent liver resection (validation set 1) and in patients who underwent liver transplantation (validation set 2) using a receiver operating characteristic curve analysis. The area under the curves (AUCs) of these three groups were compared. RESULTS: A total of 345 patients with 356 HCCs were selected for analysis. Tumor diameter (D) (P = 0.021), tumor washout (TW) (P < 0.01), and peritumoral hypointensity in the hepatobiliary phase (PHH) (P < 0.01) were significantly associated with MVI after multivariate analysis. The AUCs for predicting MVI of the predictive formula were as follows: training set, 0.88 (95% confidence interval (CI) 0.82,0.93); validation set 1, 0.81 (95% CI 0.73,0.87); validation set 2, 0.67 (95% CI 0.51,0.80). The AUCs were not significantly different among three groups (training set vs validation set 1; P = 0.15, training set vs validation set 2; P = 0.09, validation set 1 vs validation set 2; P = 0.29, respectively). CONCLUSION: Our multiparametric assessment of gadoxetic acid-enhanced MRI performed quite precisely and with good reproducibility for predicting MVI.

Comparison of diagnostic performance of radiologist- and AI-based assessments of T2-FLAIR mismatch sign and quantitative assessment using synthetic MRI in the differential diagnosis between astrocytoma, IDH-mutant and oligodendroglioma, IDH-mutant and 1p/19q-codeleted.

PURPOSE: This study aimed to compare assessments by radiologists, artificial intelligence (AI), and quantitative measurement using synthetic MRI (SyMRI) for differential diagnosis between astrocytoma, IDH-mutant and oligodendroglioma, and IDH-mutant and 1p/19q-codeleted and to identify the superior method. METHODS: Thirty-three cases (men, 14; women, 19) comprising 19 astrocytomas and 14 oligodendrogliomas were evaluated. Four radiologists independently evaluated the presence of the T2-FLAIR mismatch sign. A 3D convolutional neural network (CNN) model was trained using 50 patients outside the test group (28 astrocytomas and 22 oligodendrogliomas) and transferred to evaluate the T2-FLAIR mismatch lesions in the test group. If the CNN labeled more than 50% of the T2-prolonged lesion area, the result was considered positive. The T1/T2-relaxation times and proton density (PD) derived from SyMRI were measured in both gliomas. Each quantitative parameter (T1, T2, and PD) was compared between gliomas using the Mann-Whitney U-test. Receiver-operating characteristic analysis was used to evaluate the diagnostic performance. RESULTS: The mean sensitivity, specificity, and area under the curve (AUC) of radiologists vs. AI were 76.3% vs. 94.7%; 100% vs. 92.9%; and 0.880 vs. 0.938, respectively. The two types of diffuse gliomas could be differentiated using a cutoff value of 2290/128 ms for a combined 90th percentile of T1 and 10th percentile of T2 relaxation times with 94.4/100% sensitivity/specificity with an AUC of 0.981. CONCLUSION: Compared to the radiologists' assessment using the T2-FLAIR mismatch sign, the AI and the SyMRI assessments increased both sensitivity and objectivity, resulting in improved diagnostic performance in differentiating gliomas.

Effect of lipiodol marking before CT-guided cryoablation on the outcome of sporadic renal cell carcinoma.

PURPOSE: This retrospective study evaluates the impact of preoperative lipiodol marking on the outcomes of computed tomography (CT)-guided cryoablation for histologically diagnosed sporadic renal cell carcinoma (RCC). METHODS: This study analyzed the data of 173 patients who underwent CT-guided cryoablation for histologically proven sporadic RCC at a single institution between April 2014 and December 2020. The local control rate (LCR), recurrence-free survival rate (RFSR), overall survival rate (OSR), changes in renal function, and complications in patients with (n = 85) and without (n = 88) preoperative lipiodol marking were compared. RESULTS: The 5-year LCR and 5-year RFSR were significantly higher in patients with lipiodol marking (97.51% and 93.84%, respectively) than in those without (72.38% and 68.10%, respectively) (P value <0.01, log-rank test). There were no significant differences between the two groups regarding the 5-year OSR (97.50% vs. 86.82%) or the deterioration in chronic kidney disease stage (12.70% vs. 16.43%). Grade ≥3 complications occurred in patients with lipiodol marking (n = 2, retroperitoneal hematoma and cerebral infarction in 1 patient each) and without (n = 5; urinary fistula in 2, colonic perforation in 2, urinary infection in 1). CONCLUSION: Lipiodol marking before CT-guided cryoablation for sporadic RCC is a feasible approach to improving local control and RFS while mitigating the decline in renal function. Additionally, it may help reduce complications.

Dynamic chest radiography for pulmonary vascular diseases: clinical applications and correlation with other imaging modalities.

Dynamic chest radiography (DCR) is a novel functional radiographic imaging technique that can be used to visualize pulmonary perfusion without using contrast media. Although it has many advantages and clinical utility, most radiologists are unfamiliar with this technique because of its novelty. This review aims to (1) explain the basic principles of lung perfusion assessment using DCR, (2) discuss the advantages of DCR over other imaging modalities, and (3) review multiple specific clinical applications of DCR for pulmonary vascular diseases and compare them with other imaging modalities.

Transvaginal approach combined intracavitary and interstitial brachytherapy assisted by transrectal ultrasound: results from 30 patients with locally advanced cervical cancer.

PURPOSE: This study evaluated the efficacy and safety of transvaginal approach combined intracavitary and interstitial brachytherapy (IC/IS BT) assisted by transrectal ultrasound (TRUS) for treatment of locally advanced cervical cancer (LACC). MATERIALS AND METHODS: A total of 30 patients of LACC treated with external beam radiotherapy and IC/IS BT via transvaginal approach assisted by transrectal ultrasound were observed retrospectively. The 2-year local control (LC), progression-free survival (PFS), and overall survival (OS) were analyzed using the Kaplan-Meier method. Late adverse events were also evaluated to assess the safety of IC/IS BT. RESULTS: The median follow-up period was 22 months. The 2-year LC, PFS, and OS were 90%, 61%, and 82%, respectively. We observed no critical complications related to the IC/IS BT technique. Late adverse events of grade 3 or more included one case of grade 4 colon perforation. CONCLUSION: Our patient series demonstrated that radiotherapy combined with transvaginal approach, TRUS-assisted IC/IS BT achieves favorable local control and safety for LACC.

Refined scan protocol for the evaluation of pulmonary perfusion standardized image quality and reduced radiation dose in dynamic chest radiography.

PURPOSE: Dynamic chest radiography (DCR) is a novel imaging technique used to noninvasively evaluate pulmonary perfusion. However, the standard DCR protocol, which is roughly adapted to the patient's body size, occasionally causes over- or underexposure, which could influence clinical evaluation. Therefore, we proposed a refined protocol by increasing the number of patient body mass index (BMI) categories from three to seven groups and verified its usefulness by comparing the image sensitivity indicators (S-values) and entrance surface doses (ESDs) of the conventional protocol with those of our refined protocol. METHODS: This retrospective observational study included 388 datasets (standing position, 224; supine position, 164) for the conventional protocol (December 2019-April 2021) and 336 datasets (standing position, 233; supine position, 103) for the refined protocol (June-November 2021). The conventional protocol (BMI-3 protocol) divided the patients into three BMI groups (BMI < 17, 17≤BMI < 25, and BMI ≥ 25 kg/m2 ), whereas the refined protocol (BMI-7 protocol) divided the patients into seven BMI groups (BMI < 17, 17 ≤ BMI < 20, 20 ≤ BMI < 23, 23 ≤ BMI < 26, 26 ≤ BMI < 29, 29 ≤ BMI < 32, and BMI ≥ 32 kg/m2 ). The coefficients of variation (CVs) for the S-values and ESDs acquired using the two protocols were compared. RESULTS: The CVs of the S-values in the BMI-7 protocol group were significantly lower than those in the BMI-3 protocol group for the standing (28.8% vs. 16.7%; p < 0.01) and supine (24.5% vs. 17.7%; p < 0.01) positions. The ESDs of patients scanned using the BMI-7 protocol were significantly lower than those scanned using the BMI-3 protocol in the standing (1.3 vs. 1.1 mGy; p < 0.01) and supine positions (2.5 vs. 1.6 mGy; p < 0.01), although the mean BMI of the two groups were similar. CONCLUSION: We introduced the BMI-7 protocol and demonstrated its standardized image quality and reduced radiation exposure in patients undergoing DCR.

The Feasibility of Deep Learning-Based Reconstruction for Low-Tube-Voltage CT Angiography for Transcatheter Aortic Valve Implantation.

OBJECTIVE: The purpose of this study is to evaluate the efficacy of deep learning reconstruction (DLR) on low-tube-voltage computed tomographic angiography (CTA) for transcatheter aortic valve implantation (TAVI). METHODS: We enrolled 30 patients who underwent TAVI-CT on a 320-row CT scanner. Electrocardiogram-gated coronary CTA (CCTA) was performed at 100 kV, followed by nongated aortoiliac CTA at 80 kV using a single bolus of contrast material. We used hybrid-iterative reconstruction (HIR), model-based IR (MBIR), and DLR to reconstruct these images. The contrast-to-noise ratios (CNRs) were calculated. Five-point scales were used for the overall image quality analysis. The diameter of the aortic annulus was measured in each reconstructed image, and we compared the interobserver and intraobserver agreements. RESULTS: In the CCTA, the CNR and image quality score for DLR were significantly higher than those for HIR and MBIR ( P < 0.01). In the aortoiliac CTA, the CNR for DLR was significantly higher than that for HIR ( P < 0.01) and significantly lower than that for MBIR ( P ≤ 0.02). The image quality score for DLR was significantly higher than that for HIR ( P < 0.01). No significant differences were observed between the image quality scores for DLR and MBIR. The measured aortic annulus diameter had high interobserver and intraobserver agreement regardless of the reconstruction method (all intraclass correlation coefficients, >0.89). CONCLUSIONS: In low tube voltage TAVI-CT, DLR provides higher image quality than HIR, and DLR provides higher image quality than MBIR in CCTA and is visually comparable to MBIR in aortoiliac CTA.

The cortical high-flow sign of oligodendroglioma, IDH-mutant and 1p/19q-codeleted: comparison between arterial spin labeling and dynamic susceptibility contrast methods.

PURPOSE: The cortical high-flow sign with the non-enhancing area was reportedly found to be more frequent with oligodendroglioma, IDH-mutant and 1p/19q codeleted (ODG IDHm-codel) than with IDH-wildtype or astrocytoma, IDH-mutant on arterial spin labeling (ASL) in diffuse gliomas. This study aimed to compare the identification rate of the cortical high-flow sign on ASL in patients with ODG IDHm-codel to that on dynamic susceptibility contrast-enhanced perfusion-weighted imaging (DSC-PWI). METHODS: Participants consisted of 32 adult ODG IDHm-codel patients with pathologically confirmed. Subtraction images were generated from paired control and label images on ASL. For DSC, dynamic T2*-weighted perfusion weighted images were obtained after pre-bolus of gadolinium-based contrast agent. Regional cerebral blood flow/volume maps were generated based on the concentration-time curve and arterial input function. Tumor-affecting cortices without contrast enhancement on conventional MR imaging were targeted. The identification rate of the cortical high-flow sign was compared between ASL and DSC using the Pearson's Chi-Square test. RESULTS: Frequency of the cortical high-flow sign was significantly higher on ASL (18/32, 56.3%; p < 0.001) than on DSC (5/32, 15.6%). All cases with the positive cortical high-flow sign on DSC were identified on ASL. CONCLUSION: ASL effectively identifies the cortical high-flow sign in ODG IDHm-codel, surpassing DSC in identification rates.

Incidence and severity of pulmonary embolism in COVID-19 infection: Ancestral, Alpha, Delta, and Omicron variants.

Little information is available regarding incidence and severity of pulmonary embolism (PE) across the periods of ancestral strain, Alpha, Delta, and Omicron variants. The aim of this study is to investigate the incidence and severity of PE over the dominant periods of ancestral strain and Alpha, Delta, and Omicron variants. We hypothesized that the incidence and the severity by proximity of PE in patients with the newer variants and vaccination would be decreased compared with those in ancestral and earlier variants. Patients with COVID-19 diagnosis between March 2020 and February 2022 and computed tomography pulmonary angiogram performed within a 6-week window around the diagnosis (-2 to +4 weeks) were studied retrospectively. The primary endpoints were the associations of the incidence and location of PE with the ancestral strain and each variant. Of the 720 coronavirus disease 2019 patients with computed tomography pulmonary angiogram (58.6 ± 17.2 years; 374 females), PE was diagnosed among 42/358 (12%) during the ancestral strain period, 5/60 (8%) during the Alpha variant period, 16/152 (11%) during the Delta variant period, and 13/150 (9%) during the Omicron variant period. The most proximal PE (ancestral strain vs variants) was located in the main/lobar arteries (31% vs 6%-40%), in the segmental arteries (52% vs 60%-75%), and in the subsegmental arteries (17% vs 0%-19%). There was no significant difference in both the incidence and location of PE across the periods, confirmed by multivariable logistic regression models. In summary, the incidence and severity of PE did not significantly differ across the periods of ancestral strain and Alpha, Delta, and Omicron variants.

Diagnostic MR imaging features of hypomyelination of early myelinating structures: A case report.

Hypomyelination of early myelinating structures (HEMS) has recently been defined as a new genetic disorder accompanied by clinical and MR imaging characteristics. However, no studies have focused on diffusion-weighted imaging (DWI) findings of HEMS. We would like to propose a "sheep sign," which is formed by DWI hyperintensity in the medial medullary lamina along with alternating high-low-high (HLH) intensity stripes in the posterior limb of the internal capsule. We believe the presence of the "sheep sign" on DWI in combination with alternating HLH intensity stripes may be a valuable tool for diagnosing HEMS.

Arterial Spin Labeling-Based MR Angiography for Cerebrovascular Diseases: Principles and Clinical Applications.

Arterial spin labeling (ASL) is a noninvasive imaging technique that labels the proton spins in arterial blood and uses them as endogenous tracers. Brain perfusion imaging with ASL is becoming increasingly common in clinical practice, and clinical applications of ASL for intracranial magnetic resonance angiography (MRA) have also been demonstrated. Unlike computed tomography (CT) angiography and cerebral angiography, ASL-based MRA does not require contrast agents. ASL-based MRA overcomes most of the disadvantages of time-of-flight (TOF) MRA. Several schemes have been developed for ASL-based MRA; the most common method has been pulsed ASL, but more recently pseudo-continuous ASL, which provides a higher signal-to-noise ratio (SNR), has been used more frequently. New methods that have been developed include direct intracranial labeling methods such as velocity-selective ASL and acceleration-selective ASL. MRA using an extremely short echo time (eg, silent MRA) or ultrashort echo-time (TE) MRA can suppress metal susceptibility artifacts and is ideal for patients with a metallic device implanted in a cerebral vessel. Vessel-selective 4D ASL MRA can provide digital subtraction angiography (DSA)-like images. This review highlights the principles, clinical applications, and characteristics of various ASL-based MRA techniques. LEVEL OF EVIDENCE: 5 TECHNICAL EFFICACY: Stage 2.

Combination of Clinical Factors and Radiomics Can Predict Local Recurrence and Metastasis After Stereotactic Body Radiotherapy for Non-small Cell Lung Cancer.

BACKGROUND/AIM: Radiomics, which links radiological image features with patient prognoses, is expected to be applied for the prediction of the clinical outcomes of radiotherapy. We investigated the clinical and radiomic factors associated with recurrence patterns after stereotactic body radiotherapy (SBRT) for non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: We retrospectively analyzed 125 patients with histologically confirmed NSCLC who underwent SBRT between April 2003 and June 2017 at our institution. A radiomic score was calculated from five radiomics features (histogram and texture features) selected using the LASSO Cox regression model. These features were extracted from the gross tumor volume (GTV) in three-dimensional wavelet decomposition CT images. We used univariate and multivariate analyses to determine the associations between local control (LC) time and metastasis-free survival (MFS), clinical factors (age, sex, performance status, operability, smoking, histology, and tumor diameter), and the radiomic score. RESULTS: With a median follow-up of 37 months, the following 3-year rates were observed: overall survival, 80.9%; progression-free survival, 61.7%; LC, 75.1%, and MFS; 74.5%. In multivariate analysis, histology (squamous cell carcinoma vs. non-squamous cell carcinoma, p=0.0045), tumor diameter (>3 cm vs. ≤3 cm, p=0.039); and radiomic score (>0.043 vs. ≤0.043, p=0.042) were significantly associated with LC, and the radiomic score (>0.304 vs. ≤0.304, p<0.001) was significantly associated with MFS. CONCLUSION: Histology, tumor diameter, and radiomic score could be significant factors for predicting NSCLC recurrence patterns after SBRT.

Reproducibility of quantitative ADC, T1, and T2 measurement on the cerebral cortex: Utility of whole brain echo-planar DWI with compressed SENSE (EPICS-DWI): A pilot study.

Purpose: To assess the reproducibility of ADC, T1, T2, and proton density (PD) measurements on the cortex across the entire brain using high-resolution pseudo-3D diffusion-weighted imaging using echo-planar imaging with compressed SENSE (EPICS-DWI) and 3D quantification with an interleaved Look-Locker acquisition sequence with T2 preparation pulse (3D-QALAS) in normal healthy adults. Methods: Twelve healthy participants (median age, 33 years; range, 28-51 years) were recruited to evaluate the reproducibility of whole-brain EPICS-DWI and synthetic MRI. EPICS-DWI utilizes a compressed SENSE reconstruction framework while maintaining the EPI sampling pattern. The 3D-QALAS sequence is based on multi-acquisition 3D gradient echo, with five acquisitions equally spaced in time, interleaved with a T2 preparation pulse and an inversion pulse. EPICS-DWI (b values, 0 and 1000 s/mm2) and 3D-QALAS sequence with identical voxel size on a 3.0-T MR system were performed twice (for test-retest scan). Intraclass correlation coefficients (ICCs) for ADC, T1, T2, and PD for all parcellated volume of interest (VOI) per subject on scan-rescan tests were calculated to assess reproducibility. Bland-Altman plots were used to investigate discrepancies in ADCs, T1s, T2s, and PDs obtained from the two MR scans. Results: The ICC of ADCs was 0.785, indicating "good" reproducibility. The ICCs of T1s, T2s, and PDs were 0.986, 0.978, and 0.968, indicating "excellent" reproducibility. Conclusion: The combination of EPICS-DWI and 3D-QALAS sequences with identical voxel size could reproducible ADC, T1, T2, and PD measurements for the cortex across the entire brain in healthy adults.

Impact of portal-phase signal intensity of dynamic gadoxetic acid-enhanced magnetic resonance imaging in hepatocellular carcinoma.

PURPOSE: To evaluate the prognostic impact of dynamic gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) in patients with hepatocellular carcinoma (HCC). METHODS: We retrospectively reviewed the data of 206 patients with HCC who underwent preoperative Gd-EOB-DTPA-enhanced MRI and hepatectomy and quantitatively evaluated the signal intensity ratio of the tumor to the surrounding liver tissue in the portal phase (SIRPP). We verified the survival rates and assessed the prognostic factors associated with overall survival (OS) and recurrence-free survival (RFS) using SIRPP. RESULTS: Multivariate analysis revealed that the independent predictive factors for poorly-differentiated HCC were α-fetoprotein > 20 ng/mL (hazard ratio [HR]: 3.1909, 95% confidence interval [CI]: 1.3464-7.5622, p = .0084) and SIRPP ≤ 0.85 (HR: 3.7155, 95% CI: 1.521-9.076, p = .004). The 5-year OS and RFS rates in the high and low SIRPP groups were 83.2 and 52.1%, respectively (p < .0001) and 49.7 and 18.5%, respectively (p = .0003). Multivariate analysis revealed that SIRPP ≤ 0.68 was an independent prognostic factor related to OS (HR: 4.4537, 95% CI: 1.6581-11.9626, p = .003). CONCLUSION: The SIRPP of preoperative Gd-EOB-DTPA-enhanced MRI might predict the histological differentiation and prognosis of HCC.