3-dimensional Magnetic Resonance Imaging Research Articles

Morphological characteristics of cerebellum, pons and thalamus in Reccurent isolated sleep paralysis - A pilot study.

Recurrent isolated sleep paralysis (RISP) is a rapid eye movement sleep (REM) parasomnia, characterized by the loss of voluntary movements upon sleep onset and/or awakening with preserved consciousness. Evidence suggests microstructural changes of sleep in RISP, although the mechanism of this difference has not been clarified yet. Our research aims to identify potential morphological changes in the brain that can reflect these regulations. We recruited 10 participants with RISP (8 women; mean age 24.7 years; SD 2.4) and 10 healthy control subjects (w/o RISP; 3 women; mean age 26.3 years; SD 3.7). They underwent video-polysomnography (vPSG) and sleep macrostructure was analyzed. After that participants underwent magnetic resonance imaging (MRI) of the brain. We focused on 2-dimensional measurements of cerebellum, pons and thalamus. Statistical analysis was done in SPSS program. After analysis for normality we performed Mann-Whitney U test to compare our data. We did not find any statistically significant difference in sleep macrostructure between patients with and w/o RISP. No evidence of other sleep disturbances was found. 2-dimensional MRI measurements revealed statistically significant increase in cerebellar vermis height (p = 0.044) and antero-posterior diameter of midbrain-pons junction (p = 0.018) in RISP compared to w/o RISP. Our results suggest increase in size of cerebellum and midbrain-pons junction in RISP. This enlargement could be a sign of an over-compensatory mechanism to otherwise dysfunctional regulatory pathways. Further research should be done to measure these differences in time and with closer respect to the frequency of RISP episodes.

Three-Dimensional MRI of Foot and Ankle: Current Perspectives and Advantages Over 2D MRI

The foot and ankle region, distinguished by its complex and intricate anatomy, is frequently susceptible to injuries, particularly in the context of sports-related activities and fall-related trauma. This article reviews the literature with respect to 3-Dimensional (3D) magnetic resonance imaging (MRI) of foot and ankle. Technical considerations and imaging and interpretation-related advantages and pitfalls will be discussed with relevant case examples. 3D MRI is advantageous over 2-Dimensional (2D) MRI in producing higher spatial resolution in a short duration of time with less partial volume artifacts and in creating structure-specific imaging using multiplanar and curved planar reconstructions. The reader will be able to apply such principles in their practice in obtaining higher-resolution volume imaging of ankle and foot with respect to ligaments, tendons, articular cartilage, plantar fascia, plantar plate, and peripheral nerves for the benefit of their patients and referring physicians.

Evaluation of Cochlear Implantation in Children With Cochlear Nerve Absence or Deficiency.

To identify associations between cochleovestibular anatomy findings and hearing outcomes found in children with imaging evidence of an absent or hypoplastic cochlear nerve treated with cochlear implantation (CI). retrospective review. Cochlear implant program at tertiary care center. A retrospective review was performed to identify children with imaging evidence of cochlear nerve absence or deficiency who underwent CI evaluation. High-resolution 3-dimensional T2-weighted magnetic resonance imaging in the oblique sagittal and axial planes were reviewed by a neuroradiologist to identify cochleovestibular anatomy. Hearing was assessed pre and postoperatively with Speech Perception Category scores. Seven CI recipients were identified (n = 10 ears) who had bilateral severe to profound sensorineural hearing loss with lack of auditory development with binaural hearing aid trial and imaging evidence of cochlear nerve aplasia/hypoplasia. All ears had 2 nerves in the cerebellopontine angle (100%, n = 10), half of the ears had evidence of 2 or less nerves in the internal auditory canal (IAC). All children showed large improvement in speech perception after CI. Our experience with CIs for children with absent or hypoplastic cochlear nerves demonstrates that CI can be a viable option in select patients who satisfy preoperative audiological criteria. Radiological identification of a hypoplastic or aplastic cochlear nerve does not preclude auditory innervation of the cochlea. CI recipients in this subgroup must be counseled on difficulty in predicting postimplantation language and speech outcomes, and cautioned about facial nerve stimulation.

Thoracic aorta injury detected by 4D flow MRI predicts subsequent main adverse cardiovascular events in breast cancer patients receiving anthracyclines: A longitudinal study

PurposeTo investigate longitudinal thoracic aorta injury using 3-dimensional phase-contrast magnetic resonance imaging (4D flow MRI) parameters and to evaluate their value for predicting the subsequent main adverse cardiovascular events (MACEs) in breast cancer patients receiving anthracyclines. MethodsBetween July 2020 and July 2021, eighty-eight female participants with breast cancer scheduled to receive anthracyclines with or without trastuzumab prospectively enrolled. Each subjects underwent 4D flow MRI at baseline, 3 and 6 months in relation to baseline. The diameter, peak velocity (Vpeak), wall shear stress (WSS), pulse wave velocity (PWV), energy loss (EL) and pressure gradient (PG) of thoracic aorta were measured. The association between these parameters and subsequent MACEs was performed by Cox proportional hazard models. ResultsTen participants had subsequently MACEs. The Vpeak and PG gradually decreased and the WSS, PWV and EL progressively increased at 3 and 6 months compared with baseline. Adjusted multivariable analysis showed that the WSS of the proximal, mid- and distal ascending aorta [HR, 1.314 (95% confidence interval (CI): 1.003, 1.898)], [HR, 1.320 (95% CI: 1.002, 1.801)] and [HR, 1.322 (95% CI: 1.001, 1.805)] and PWV of ascending aorta [HR, 2.223 (95% CI: 1.010, 4.653)] at 3 months were associated with subsequent MACEs. Combined WSS and PWV of ascending aorta at 3 months yielded the highest AUC (0.912) for predicting subsequent MACEs. ConclusionCombined WSS and PWV of ascending aorta at 3 months is helpful for predicting the subsequent MACEs in breast cancer patients treated by anthracyclines.

Associations of dietary patterns and longitudinal brain-volume change in Japanese community-dwelling adults: results from the national institute for longevity sciences-longitudinal study of aging

BackgroundThe association of dietary patterns and longitudinal changes in brain volume has rarely been investigated in Japanese individuals. We prospectively investigated this association in middle-aged and older Japanese community-dwelling adults.MethodsData with a 2-year follow-up from the sixth wave (July 2008 to July 2010; baseline) to the seventh (July 2010 to July 2012; follow-up) of the National Institute for Longevity Sciences-Longitudinal Study of Aging project were analyzed. Dietary intake was assessed using a 3-day dietary record, and longitudinal volume changes (%) in the total gray matter (TGM), total white matter, and frontal, parietal, occipital, temporal, and insular lobes were assessed using 3-dimensional T1 magnetic resonance imaging scans. Multiple factor analysis and hierarchical clustering revealed sex-specific dietary patterns. Associations between dietary patterns and annual brain-volume changes (%) were evaluated using general linear models adjusted for age, apoprotein E genotype, body mass index, medical history, lifestyle behaviors, socioeconomic factors, and energy intake.ResultsAmong the 1636 participants (age: 40.3–89.2 years), three dietary patterns were determined for men (n = 815; Western; Vegetable-Fruit-Dairy; and Traditional Japanese diets) and women (n = 821; Western; Grain-Vegetable-Fruit; and Traditional Japanese diets). Compared to women following the Western diet, those on the Traditional Japanese diet had less TGM atrophy. Multivariable-adjusted β (95% confidence interval) of the annual change (%) of TGM was − 0.145 (-0.287 to -0.002; P = 0.047), which correlated with reduced parietal lobe atrophy. No association between dietary pattern and brain atrophy was observed in men.ConclusionsAdherence to healthy dietary patterns, with higher consumption of whole grains, seafood, vegetables, fruits, mushrooms, soybean products, and green tea, potentially confers a protective effect against brain atrophy in middle-aged and older Japanese women but not in men. Further research to confirm these results and ascertain the underlying mechanisms is required. This study highlights the importance of sex-specific effects on the relationship between dietary patterns and brain health in diverse populations.

Altered cortical thickness-based structural covariance networks in type 2 diabetes mellitus

Cognitive impairment is a common complication of type 2 diabetes mellitus (T2DM), and early cognitive dysfunction may be associated with abnormal changes in the cerebral cortex. This retrospective study aimed to investigate the cortical thickness-based structural topological network changes in T2DM patients without mild cognitive impairment (MCI). Fifty-six T2DM patients and 59 healthy controls underwent neuropsychological assessments and sagittal 3-dimensional T1-weighted structural magnetic resonance imaging. Then, we combined cortical thickness-based assessments with graph theoretical analysis to explore the abnormalities in structural covariance networks in T2DM patients. Correlation analyses were performed to investigate the relationship between the altered topological parameters and cognitive/clinical variables. T2DM patients exhibited significantly lower clustering coefficient (C) and local efficiency (Elocal) values and showed nodal property disorders in the occipital cortical, inferior temporal, and inferior frontal regions, the precuneus, and the precentral and insular gyri. Moreover, the structural topological network changes in multiple nodes were correlated with the findings of neuropsychological tests in T2DM patients. Thus, while T2DM patients without MCI showed a relatively normal global network, the local topological organization of the structural network was disordered. Moreover, the impaired ventral visual pathway may be involved in the neural mechanism of visual cognitive impairment in T2DM patients. This study enriched the characteristics of gray matter structure changes in early cognitive dysfunction in T2DM patients.

Quantitative evaluation of natural progression of fatty infiltration and muscle atrophy in chronic rotator cuff tears without tear extension using magnetic resonance imaging

BackgroundThe pathology of and mechanisms underlying muscle degeneration remain unclear. We aimed to quantitatively evaluate the natural changes in fatty infiltration and muscle atrophy in patients with chronic rotator cuff tears using 3-dimensional 2-point Dixon magnetic resonance imaging (MRI). MethodsThirty patients with nonoperatively observed rotator cuff tears without tear extension were evaluated using multiple MRI examinations with a minimum interval of 2 years. The fatty infiltration ratio (%fat) and muscle volume of the rotator cuff muscles were compared between the two examinations in those with supraspinatus tear <2 cm (<2 cm SSP group), supraspinatus tear ≥2 cm (≥2 cm SSP group), and massive tear (massive group). The supraspinatus (SSP), infraspinatus and teres minor (ISP+TM), and subscapularis (SSC) muscles were evaluated. ResultsThe massive group showed a significantly greater %fat than the <2 and ≥2 cm SSP groups in the SSP (P=0.002) and ISP+TM muscles (P<0.001). The total muscle volume did not differ among the three groups for all rotator cuff muscle components. The %fat values did not change in any rotator cuff components during the follow-up period in all groups. The total muscle volume in the massive group significantly decreased in the SSP (P=0.018) and ISP+TM muscles (P=0.013). ConclusionThe present results indicate that fatty infiltration of the torn muscle occurs in the early phase after a rotator cuff tear, whereas muscle atrophy appears to progress gradually in chronic rotator cuff tears. Early intervention before muscle degeneration should be considered if the tear involves the infraspinatus tendon.

Unsupervised Representation Learning for 3-Dimensional Magnetic Resonance Imaging Super-Resolution with Degradation Adaptation

Unsupervised Representation Learning for 3-Dimensional Magnetic Resonance Imaging Super-Resolution with Degradation Adaptation

Using Novel Segmentation Technology to Define Safe Corridors for Minimally Invasive Posterior Lumbar Interbody Fusion.

There has been a rise in minimally invasive methods to access the intervertebral disk space posteriorly given their decreased tissue destruction, lower blood loss, and earlier return to work. Two such options include the percutaneous lumbar interbody fusion through the Kambin triangle and the endoscopic transfacet approach. However, without accurate preoperative visualization, these approaches carry risks of damaging surrounding structures, especially the nerve roots. Using novel segmentation technology, our goal was to analyze the anatomic borders and relative sizes of the safe triangle, trans-Kambin, and the transfacet corridors to assist surgeons in planning a safe approach and determining cannula diameters. The areas of the safe triangle, Kambin, and transfacet corridors were measured using commercially available software (BrainLab, Munich, Germany). For each approach, the exiting nerve root, traversing nerve roots, theca, disk, and vertebrae were manually segmented on 3-dimensional T2-SPACE magnetic resonance imaging using a region-growing algorithm. The triangles' borders were delineated ensuring no overlap between the area and the nerves. A total of 11 patients (65.4 ± 12.5 years, 33.3% female) were retrospectively reviewed. The Kambin, safe, and transfacet corridors were measured bilaterally at the operative level. The mean area (124.1 ± 19.7 mm2 vs 83.0 ± 11.7 mm2 vs 49.5 ± 11.4 mm2) and maximum permissible cannula diameter (9.9 ± 0.7 mm vs 6.8 ± 0.5 mm vs 6.05 ± 0.7 mm) for the transfacet triangles were significantly larger than Kambin and the traditional safe triangles, respectively (P < .001). We identified, in 3-dimensional, the borders for the transfacet corridor: the traversing nerve root extending inferiorly until the caudal pedicle, the theca medially, and the exiting nerve root superiorly. These results illustrate the utility of preoperatively segmenting anatomic landmarks, specifically the nerve roots, to help guide decision-making when selecting the optimal operative approach.

Association between Serum Triglycerides and Severity of Stroke

Abstract Background: The purpose of the present research was to study the correlation between serum triglyceride (TG) levels and the severity of stroke as limited data are available on the role of TGs. The severity of stroke was determined using the Scandinavian Stroke Scale (SSS). Methods: In this cross-sectional study, 60 patients with acute ischemic stroke were included, who were diagnosed on clinical examination and 3-dimensional magnetic resonance imaging scan of the brain. Serum TG levels were categorized according to the National Cholesterol Education Program and the Adult Treatment Panel. Stroke severity was assessed with the help of SSS. Results: The mean serum TG levels in the study were found to be 147.7 mg/dl ± 92 mg/dl. The mean SSS score in the study was 27.93 ± 3.86. There was a statistically significant association between the serum TG levels and SSS (P = 0.001). The association was suggested by a positive Pearson correlation coefficient (r = 0.481). Patients with low serum TG levels (≤150 mg/dl) had severe strokes as assessed by the SSS (≤25). Conclusion: This study confirms that low levels of TG are associated with poor outcome of acute ischemic stroke, which can be explained by the fact that low serum TG levels indicate malnutrition, which is a poor prognostic factor.

Application of Sequential Thresholding-Based Automated Reconstruction of the Trigeminal Nerve in Trigeminal Neuralgia

High-resolution magnetic resonance imaging (MRI) of the trigeminal nerve is indispensable for workup of trigeminal neuralgia (TN) before microvascular decompression; however, the evaluation is often subjective and prone to variability. We aim to develop and assess sequential thresholding-based automated reconstruction ofthe trigeminal nerve (STAR-TN) as an algorithm for segmenting the trigeminal nerve and contacting structures that will allow for a structured method for assessing neurovascular conflict. A total of 42 patients with TN who underwent high-resolution MRI before microvascular decompression in 2022 were included in our study. Segmentation of the trigeminal nerve and contacting structures was performed on preoperative MRI scans using STAR-TN. The segmentations were then evaluated for neurovascular conflict and compared to the preoperative radiology and operative notes. Geometric features, including the area of contact and distance to conflict, were extracted. Of the 42 patients, 32 (76.2%) were found to show neurovascular conflict based solely on their STAR-TN segmentations and 10 (23.8%) were found to not show neurovascular conflict. Compared with the intraoperative findings, this resulted in a sensitivity of 78.0% and specificity of 100%. In contrast, assessments of neurovascular conflict by radiologists using only 2-dimensional MRI views had a sensitivity of 68.3% and specificity of 100%. Of the 32 patients with neurovascular conflict, 29 (90.9%) had conflict within the root entry zone. Overall, the patients had a median area of contact of 10.66 mm2. STAR-TN allows for 3-dimensional visualization and identification of neurovascular conflict with improved sensitivity compared with neuroradiologist assessments from MRI slices.

Correlation of metal ions with specific brain region volumes in neurodegenerative diseases.

There are reports stating that deteriorations in metal homeostasis in neurodegenerative diseases promote abnormal protein accumulation. In this study, the serum metal levels in Alzheimer's disease (AD) and Parkinson's disease (PD) and its relationship with the cortical regions of the brain were investigated. The patients were divided into 3 groups consisting of the AD group, PD group, and healthy control group (n = 15 for each). The volumes of specific brain regions were measured over the participants' 3-dimensional magnetic resonance images, and they were compared across the groups. Copper, zinc, iron, and ferritin levels in the serums were determined, and their correlations with the brain region volumes were examined. The volumes of left hippocampus and right substantia nigra were lower in the AD and PD groups, while the volume of the left nucleus caudatus (CdN) and bilateral insula were lower in the AD group compared to the control group. Serum zinc levels were lower in the AD and PD groups, while the iron level was lower in the PD group in comparison to the control group. In addition, the serum ferritin level was higher in the AD group than in the control group. Serum zinc and copper levels in the AD group were positively correlated with the volumes of the right entorhinal cortex, thalamus, CdN, and insula. Serum zinc and copper levels in the PD group showed a negative correlation with the left nucleus accumbens (NAc), right putamen, and right insula volumes. While the serum ferritin level in the PD group displayed a positive correlation with the bilateral CdN, putamen, and NAc, as well as the right hippocampus and insula volumes, no area was detected that showed a correlation with the serum ferritin level in the AD group. A relationship was determined between the serum metal levels in the AD and PD groups and certain brain cortical regions that showed volumetric changes, which can be important for the early diagnosis of neurodegenerative diseases.

Prospective randomized controlled trial of the safety and feasibility of a novel mesenchymal precursor cell therapy in hypoplastic left heart syndrome

ObjectiveTo assess the safety and feasibility of low-dose, novel, allogenic mesenchymal precursor cell (MPC) therapy as an adjunct to left ventricular (LV) recruitment for patients with hypoplastic left heart syndrome (HLHS) and borderline left ventricles. MPC injections into the hypoplastic left ventricle may stimulate neovascularization and beneficial LV remodeling and may improve the likelihood of achieving biventricular (BiV) or 1.5 ventricle (1.5V) circulation. MethodsChildren <5 years with prior single ventricle palliation undergoing LV recruitment surgery at a single center were randomized to MPC injections into the LV endocardium/papillary muscles (MPCs) or standard-of-care (controls) and followed for 24 months. The primary endpoint was safety, including (serious) adverse events (S/AEs), and panel reactive antibodies (PRAs). Secondary endpoints included BiV/1.5V conversion and LV size and function. ResultsNineteen subjects were enrolled, including 9 MPC recipients and 10 controls. Fourteen patients (74%) had >1 AE, and 2 patients had SAEs, both deemed unrelated to the trial product. AE severity and frequency were similar in the 2 groups. Baseline PRA levels were high, with no difference between the groups at 12 months. The overall probability of BiV/1.5V conversion was 0.16 (95% confidence interval [CI], 0.05 to 0.41) at 12 months and 0.52 (95% CI, 0.31 to 0.77) at 24 months. For patients with imaging data at both time points, increases in LV volumes from baseline to 12 months were larger in the MPC group by 3-dimensional echocardiography and cardiac magnetic resonance imaging. For children who successfully underwent BiV conversion (n = 12), full BiV conversion was achieved at 24 months in 5 of 5 (100%) MPC-treated children compared with 4 of 7 (57%) controls. ConclusionsMPC injections were considered safe and feasible in HLHS patients. More than 50% of subjects underwent BiV/1.5V conversion within 2 years. Larger trials are needed to investigate the therapeutic potential of MPCs in this population.

Single-Plane 3-Dimensional Isotropic Spin-Echo Magnetic Resonance Imaging Reconstructions of Shoulder Exhibit Superior Correlation to Surgical Findings Than 2-Dimensional Dixon Multiplanar Magnetic Resonance Imaging.

The aim of the study is to evaluate concordance of multiplanar 2-dimensional magnetic resonance imaging (2D-MRI) versus 3D isotropic MRI for rotator cuff and labral tears with the reference standard of arthroscopic surgical findings. It was an institutional review board-approved retrospective single-center study of consecutive preoperative patients with isotropic 3D-MRI on 3-Tesla scanners, multiplanar 2D-MRI, and shoulder arthroscopy. Scapular plane-oriented contiguous multiplanar reconstructions of 3D-images were evaluated by 2 experienced fellowship-trained musculoskeletal radiologists. Variables included the following: labral tear presence and rotator-cuff tear Ellman grade, thickness, and width. Sensitivities (Sen) and specificities (Spe) were calculated for binary variables. Mean squared errors (MSE) were calculated for ordinal variables. Lower MSE indicated higher concordance. Seventy-two patients (43 female) with a mean age of 50.75 ± 9.76 years were evaluated. For infraspinatus-tear presence, 3D-MRI showed higher sensitivity (0.96) and specificity (0.68) than 2D-MRI (Sen = 0.85, Spe = 0.32) ( Psen = 0.005, Pspe = 0.002). For subscapularis-tear presence, 3D-MRI showed higher sensitivity (0.94) and specificity (0.73) compared with 2D-MRI (Sen = 0.83, Spe = 0.56) ( Psen = 0.02, Pspe = 0.04). For supraspinatus-tear presence, there was no significant difference between 3D-MRI (Sen =0.96, Spe = 0.67) compared with 2D-MRI (Sen = 0.98, Spe = 0.83) ( Psen = 0.43, Pspe = 0.63). For infraspinatus-tear thickness, 3D-MRI showed lower MSE (0.35) compared with 2D-MRI MSE (0.82) ( P = 0.01). For subscapularis-tear thickness, 3D-MRI had lower MSE (0.31) compared with 2D-MRI MSE (0.51) ( P = 0.007). However, no difference noted for supraspinatus-tear thickness when comparing 3D-MRI MSE (0.39) and 2D-MRI MSE (0.51) ( P = 0.49). For labral-tear presence, 3D-MRI had a lower MSE (0.20) compared with 2D-MRI MSE (0.57) ( P < 0.001). Three-dimensional MRI of the shoulder is time efficient with a shorter acquisition time and exhibits comparable with superior correlation to surgical findings than 2D-MRI for detection of labral tears and some rotator cuff tears. Three-dimensional MRI may be used in place of traditional 2D-MRI in detection of soft-tissue shoulder injury in centers equipped to do so.

Elastic Registration Algorithm Based on Three-dimensional Pulmonary MRI in Quantitative Assessment of Severity of Idiopathic Pulmonary Fibrosis.

To quantitatively analyze lung elasticity in idiopathic pulmonary fibrosis (IPF) using elastic registration based on 3-dimensional pulmonary magnetic resonance imaging (3D-PMRI) and to assess its' correlations with the severity of IPF patients. Thirty male patients with IPF (mean age: 62±6y) and 30 age-matched male healthy controls (mean age: 62±6y) were prospectively enrolled. 3D-PMRI was acquired with a 3-dimensional ultrashort echo time sequence in end-inspiration and end-expiration. MR images were registered from end-inspiration to end-expiration with the elastic registration algorithm. Jacobian determinants were calculated from deformation fields on color maps. The log means of the Jacobian determinants (Jac-mean) and Dice similarity coefficient were used to describe lung elasticity between 2 groups. Then, the correlation of lung elasticity with dyspnea Medical Research Council (MRC) score, exercise tolerance, health-related quality of life, lung function, and the extent of pulmonary fibrosis on chest computed tomography were analyzed. The Jac-mean of IPF patients (-0.19, [IQR: -0.22, -0.15]) decreased (absolute value), compared with healthy controls (-0.28, [IQR: -0.31, -0.24], P<0.001). The lung elasticity in IPF patients with dyspnea MRC≥3 (Jac-mean: -0.15; Dice: 0.06) was significantly lower than MRC 1 (Jac-mean: -0.22, P=0.001; Dice: 0.10, P=0.001) and MRC 2 (Jac-mean: -0.21, P=0.007; Dice: 0.09, P<0.001). In addition, the Jac-mean negatively correlated with forced vital capacity % (r=-0.487, P<0.001), forced expiratory volume 1% (r=-0.413, P=0.004), TLC% (r=-0.488, P<0.001), diffusing capacity of the lungs for carbon monoxide % predicted (r=-0.555, P<0.001), 6-minute walk distance (r=-0.441, P=0.030) and positively correlated with respiratory symptoms (r=0.430, P=0.042). Meanwhile, the Dice similarity coefficient positively correlated with forced vital capacity % (r=0.577, P=0.004), forced expiratory volume 1% (r=0.526, P=0.012), diffusing capacity of the lungs for carbon monoxide % predicted (r=0.435, P=0.048), 6-minute walk distance (r=0.473, P=0.016), final peripheral oxygen saturation (r=0.534, P=0.004), the extent of fibrosis on chest computed tomography (r=-0.421, P=0.021) and negatively correlated with activity (r=-0.431, P=0.048). Lung elasticity decreased in IPF patients and correlated with dyspnea, exercise tolerance, health-related quality of life, lung function, and the extent of pulmonary fibrosis. The lung elasticity based on elastic registration of 3D-PMRI may be a new nonradiation imaging biomarker for quantitative evaluation of the severity of IPF.

Transcriptomic Similarity Informs Neuromorphic Deviations in Depression Biotypes

BackgroundMajor depressive disorder (MDD) is complicated by population heterogeneity, motivating the investigation of biotypes through imaging-derived phenotypes. However, neuromorphic heterogeneity in MDD remains unclear, and how the correlated gene expression (CGE) connectome constrains these neuromorphic anomalies in MDD biotypes has not yet been studied. MethodsHere, we related cortical thickness deviations in MDD biotypes to a pattern of CGE connectome. Cortical thickness was estimated from 3-dimensional T1-weighted magnetic resonance images in 2 independent cohorts (discovery cohort: N = 425; replication cohort: N = 217). The transcriptional activity was measured according to Allen Human Brain Atlas. A density peak–based clustering algorithm was used to identify MDD biotypes. ResultsWe found that patients with MDD were clustered into 2 replicated biotypes based on single-patient regional deviations from healthy control participants across 2 datasets. Biotype 1 mainly exhibited cortical thinning across the brain, whereas biotype 2 mainly showed cortical thickening in the brain. Using brainwide gene expression data, we found that deviations of transcriptionally connected neighbors predicted regional deviation for both biotypes. Furthermore, putative CGE-informed epicenters of biotype 1 were concentrated on the cognitive control circuit, whereas biotype 2 epicenters were located in the social perception circuit. The patterns of epicenter likelihood were separately associated with depression- and anxiety-response maps, suggesting that epicenters of MDD biotypes may be associated with clinical efficacies. ConclusionsOur findings linked the CGE connectome and neuromorphic deviations to identify distinct epicenters in MDD biotypes, providing insight into how microscale gene expressions informed MDD biotypes.

Volume ratio and distribution rate in patients with orthostatic vertigo/dizziness using MR imaging: a comparison with vertiginous diseases

Background Orthostatic dizziness/vertigo (ODV) is characterized by lightheadedness owing to postural changes. Aims/Objectives To measure the endolymphatic space (ELS)/total fluid space (TFS) volume ratio and the distribution rate of endolymphatic fluid (ELF) of patients with ODV and compare them with those of control subjects (CS). Materials and Methods This study included 22 patients (44 ears) with ODV and 52 controls (104 ears, CS). The ELS/TFS volume ratio (%) and distribution rate (%) of the inner ear components were measured using 3-dimensional magnetic resonance imaging. Results In the ODV group, the mean ELS/TFS volume ratios of the cochlea, vestibule, and semi-circular canals (SCCs) were 12.1%, 18.6%, and 18.1%, respectively; the mean ELS distribution rates for the cochlea, vestibule, and SCCs were 27.3%, 26.2%, and 46.6%, respectively. The ELS distribution rate of the vestibule was significantly lower (p < .01) and the ELS distribution rate of the SCCs was significantly higher in the ODV than in the CS group (p < .01). Conclusions and Significance The ELS distribution rate in the vestibule + SCCs among patients with ODV did not differ from that in the CS; ELF in the vestibule moved to the SCCs, and a large amount of ELF was distributed only in the SCCs.

The value of postcontrast delayed 3D fluid-attenuated inversion recovery MRI in the diagnosis of unilateral peripheral vestibular dysfunction.

Clinically, unilateral peripheral vestibular dysfunction (UPVD) with dizziness or vertigo as the chief complaint is quite common. This study aimed to investigate the correlations between 3-dimensional fluid-attenuated inversion recovery magnetic resonance imaging (3D-FLAIR MRI) findings and cochleovestibular function test results in patients with UPVD and to explore the possible etiologies of UPVD. This retrospective study enrolled 76 patients with UPVD. Endolymphatic hydrops (EH) and perilymphatic enhancement (PE) in the vestibule and cochlea on 3D-FLAIR images, their correlations with the parameters of the cochleovestibular function test and vascular risk factors, and the immunological findings of patients with EH and PE were assessed. Of the included patients, 48.7% showed positive MRI findings (the presence of EH and PE on 1 side). The pure-tone average (PTA) was higher in patients with cochlear PE than in those with vestibular (P=0.014) and cochlear EH (P=0.02). The canal paresis (CP) value was also higher in patients with vestibular PE than in those with vestibular (P=0.002) and cochlear EH (P=0.003). Video head impulse test (vHIT) gains were lower in patients with vestibular and cochlear PE than in those with vestibular and cochlear EH (P<0.001). A positive correlation was observed between the degree of vestibular and cochlear EH and PTA (both P values <0.001). PTA and CP with a cutoff value of 32 dB and 46.5%, respectively, yielded high sensitivity and specificity in determining positive MRI findings (P<0.001 and P=0.029, respectively). The prevalence of vascular risk factors was significantly higher in patients with PE than in those with EH (P=0.033). (I) Nearly half of the patients UPVD exhibited abnormal MRI findings. Cutoff values for PTA and CP of 32 dB and 46.5%, respectively, indicated that patients were more likely to have abnormal imaging findings. (II) The severity of EH was positively correlated with hearing impairment. (III) Patients with PE showed severe hearing impairment and vestibular dysfunction, which was presumed to be associated with vascular damage.

Assessment of Ocular Deformation in Pathologic Myopia Using 3-Dimensional Magnetic Resonance Imaging

Ocular deformation in pathologic myopia can affect the entire globe. However, few studies have investigated the equatorial pattern of ocular shape. In addition, the correlation between equatorial and posterior morphology needs to be further explored. To assess global ocular deformation in pathologic myopia. This hospital-based, cross-sectional study included 180 pathologic myopic eyes with atrophic maculopathy grading C2 (diffuse chorioretinal atrophy) or more from 180 participants who underwent comprehensive ophthalmic examination, including high-resolution 3-dimensional magnetic resonance imaging. In addition, 10 nonpathologic myopic eyes of 10 participants were set as the control group. According to the cross-sectional view of equator, equatorial shape was classified as round, rectangular, pyriform (noncircular and more protruded in 1 direction), vertical-elliptical, or horizontal-elliptical; according to the nasal and inferior views, the posterior shape was categorized as spheroidal, conical, bulb-shaped, ellipsoidal, multidistorted, and barrel-shaped. Equatorial circularity and ocular sphericity were used to quantitatively assess the morphological variability of the equatorial and posterior regions, respectively. The association between ocular morphology and ocular parameters and myopic maculopathy was also investigated. The mean (SD) age of 180 participants with pathologic myopia was 55.14 (10.74) years, 127 were female (70.6%), and the mean (SD) axial length of studied eyes was 30.22 (2.25) mm. The predominant equatorial shape was pyriform (66 eyes [36.7%]), followed by round (45 eyes [25.0%]). The predominant posterior shape was bulb-shaped (97 eyes [52.2%]), followed by multidistorted (46 eyes [24.7%]). Equatorial circularity and equatorial shapes were correlated (r = -0.469; 95% CI, -0.584 to -0.346; P < .001) and ocular sphericity was correlated with posterior shapes (r = -0.533; 95% CI, -0.627 to -0.427; P < .001). In eyes with a vertical-elliptical equator, equatorial circularity and ocular sphericity were positively linearly correlated (R2 = 0.246; 95% CI, 0.050-0.496; P = .002) and the prevalence of inferior staphyloma was higher (27.8%; P = .04). Eyes with a horizontal-elliptical equator have the most horizontally oriented axis of corneal flat keratometry (median, 43.55 [interquartile range, 43.84] degrees; P = .01) and tended to present with multidistorted posterior shape (21.7%; P = .04). These findings suggest ocular deformation is common in pathologic myopia and can affect the entire eye, including the equatorial and posterior regions. The morphological classification may enhance the understanding of the diverse patterns of ocular shape in pathologic myopia.

Initial Observation of Contrast Profiles for 2-Dimensional and 3-Dimensional Magnetic Resonance Imaging Sequences in Magnetic Resonance–Guided Radiation Therapy for Locally Advanced Pancreatic Cancer

In our experience treating locally advanced pancreatic cancer with magnetic resonance-guided radiation therapy (MRgRT), the true-fast imaging with steady-state free precession sequences used to generate both the real-time 2-dimensional (2D) magnetic resonance images (MRI; 2D cine) and the pretreatment high-resolution 3-dimensional (3D) MRI impart differing intensities for relevant structures between the 2 scans. Since these variations can confound target tracking selection, we propose that an understanding of the differing contrast profiles could improve selection of tracking structures. We retrospectively reviewed both 2D cine and 3D MRI images for 20 patients with pancreatic cancer treated with MRgRT. At simulation, an appropriate tracking target was identified and contoured on a single 3-mm sagittal slice of the 3D MRI. This sagittal slice was directly compared with the coregistered 7-mm 2D cine to identify structures with notable discrepancies in signal intensity. The 3D MRI was then explored in additional planes to confirm structure identities. For quantitative verification of the clinically observed differences, the pixel intensity distributions of 2D cine and 3D MRI digital imaging and communications in medicine data sets were statistically compared. In all patients reviewed, arteries (aorta, celiac, superior mesenteric artery, hepatic artery) appeared mildly hyperintense on both scans. However, veins (portal vein, superior mesenteric vein) appeared hyperintense on 2D cine but isointense on 3D MRI. Biliary structures appeared mildly hyperintense on 2D cine but starkly hyperintense on 3D MRI. The pixel intensity distributions extracted from 2D cine and 3D MRI images were confirmed to differ significantly (2 sample Kolmogorov-Smirnov test; test statistic, 0.40; P < .001). There are significant variations in image intensity between the immediate pretreatment 2D cine compared with the initial planning 3D MRI. Understanding variations of image intensity between the different MRI sequences used in MRgRT is valuable to radiation oncologists and may lead to improved target tracking and optimized treatment delivery.