Short Tau Inversion Recovery MRI Research Articles

Deep learning-based differentiation of peripheral high-flow and low-flow vascular malformations in T2-weighted short tau inversion recovery MRI.

Differentiation of high-flow from low-flow vascular malformations (VMs) is crucial for therapeutic management of this orphan disease. A convolutional neural network (CNN) was evaluated for differentiation of peripheral vascular malformations (VMs) on T2-weighted short tau inversion recovery (STIR) MRI. 527 MRIs (386 low-flow and 141 high-flow VMs) were randomly divided into training, validation and test set for this single-center study. 1) Results of the CNN's diagnostic performance were compared with that of two expert and four junior radiologists. 2) The influence of CNN's prediction on the radiologists' performance and diagnostic certainty was evaluated. 3) Junior radiologists' performance after self-training was compared with that of the CNN. Compared with the expert radiologists the CNN achieved similar accuracy (92% vs. 97%, p = 0.11), sensitivity (80% vs. 93%, p = 0.16) and specificity (97% vs. 100%, p = 0.50). In comparison to the junior radiologists, the CNN had a higher specificity and accuracy (97% vs. 80%, p < 0.001; 92% vs. 77%, p < 0.001). CNN assistance had no significant influence on their diagnostic performance and certainty. After self-training, the junior radiologists' specificity and accuracy improved and were comparable to that of the CNN. Diagnostic performance of the CNN for differentiating high-flow from low-flow VM was comparable to that of expert radiologists. CNN did not significantly improve the simulated daily practice of junior radiologists, self-training was more effective.

MRI-detected intraosseous bone marrow edema recedes after effective therapy of periodontitis

ObjectivesT2 STIR MRI sequences can detect preclinical changes associated with periodontal inflammation, i.e. intraosseous edema in the tooth-supporting bone. In this study, we assessed whether MRI can be used for monitoring periodontal disease.Material and methodsIn a prospective cohort study, we examined 35 patients with periodontitis between 10/2018 and 04/2019 by using 3D isotropic T2-weighted short tau inversion recovery (STIR) and Fast Field Echo T1-weighted Black bone sequences. All patients received standardized clinical exams before and three months after non-surgical periodontal therapy. Bone marrow edema extent was quantified in the STIR sequence at 922 sites before and after treatment. Results were compared with standard clinical findings. Non-parametric statistical analysis was performed.ResultsNon-surgical periodontal treatment caused significant improvement in mean probing depth (p < 0.001) and frequency of bleeding on probing (p < 0.001). The mean depth of osseous edema per site was reduced from a median [IQR] of 2 [1, 3] mm at baseline to 1 [0, 3] mm, (p < 0.001). Periodontal treatment reduced the frequency of sites with edema from 35 to 24% (p < 0.01).ConclusionThe decrease of periodontal bone marrow edema, as observed with T2 STIR MR imaging, is indicative of successful periodontal healing.Clinical relevance statementT2 STIR hyperintense bone marrow edema in the periodontal bone decreases after treatment and can therefore be used to evaluate treatment success. Furthermore, MRI reveals new options to depict hidden aspects of periodontitis.Key Points• T2 STIR hyperintense periodontal intraosseous edema was prospectively investigated in 35 patients with periodontitis before and after treatment and compared to clinical outcomes.• The frequency of affected sites was reduced from 35 to 24% (p < 0.001), and mean edema depth was reduced from a median [IQR] of 2 [1, 3] mm at baseline to 1 [0, 3] mm 3 months after treatment. (p < 0.001).• T2 STIR sequences can be used to monitor the posttreatment course of periodontitis.

Deep learning algorithms for magnetic resonance imaging of inflammatory sacroiliitis in axial spondyloarthritis.

The aim of this study was to develop a deep learning algorithm for detection of active inflammatory sacroiliitis in short tau inversion recovery (STIR) sequence MRI. A total of 326 participants with axial SpA, and 63 participants with non-specific back pain (NSBP) were recruited. STIR MRI of the SI joints was performed and clinical data were collected. Region of interests (ROIs) were drawn outlining bone marrow oedema, a reliable marker of active inflammation, which formed the ground truth masks from which 'fake-colour' images were derived. Both the original and fake-colour images were randomly allocated into either the training and validation dataset or the testing dataset. Attention U-net was used for the development of deep learning algorithms. As a comparison, an independent radiologist and rheumatologist, blinded to the ground truth masks, were tasked with identifying bone marrow oedema in the MRI scans. Inflammatory sacroiliitis was identified in 1398 MR images from 228 participants. No inflammation was found in 3944 MRI scans from 161 participants. The mean sensitivity of the algorithms derived from the original dataset and fake-colour image dataset were 0.86 (0.02) and 0.90 (0.01), respectively. The mean specificity of the algorithms derived from the original and the fake-colour image datasets were 0.92 (0.02) and 0.93 (0.01), respectively. The mean testing dice coefficients were 0.48 (0.27) for the original dataset and 0.51 (0.25) for the fake-colour image dataset. The area under the curve of the receiver operating characteristic (AUC-ROC) curve of the algorithms using the original dataset and the fake-colour image dataset were 0.92 and 0.96, respectively. The sensitivity and specificity of the algorithms were comparable with the interpretation by a radiologist, but outperformed that of the rheumatologist. An MRI deep learning algorithm was developed for detection of inflammatory sacroiliitis in axial SpA.

Preliminary validation of muscle ultrasound in juvenile dermatomyositis (JDM).

To compare muscle ultrasound (MUS) parameters in patients with juvenile JDM and healthy controls, and examine their association with JDM disease activity measures and MRI. MUS of the right mid-rectus femoris was performed in 21 patients with JDM meeting probable or definite Bohan and Peter criteria and 28 demographically matched healthy control subjects. MUS parameters were quantitated by digital image processing and correlated with JDM disease activity measures and semi-quantitative thigh MRI short tau inversion recovery (STIR) and T1 scores. Rectus femoris MUS echogenicity was increased (median 47.8 vs 38.5, P = 0.002) in patients with JDM compared with controls. Rectus femoris MUS echogenicity correlated with Physician Global Activity (PGA), Manual Muscle Testing (MMT), and Childhood Myositis Assessment Scale (CMAS) (rs 0.4-0.54). Some MUS parameters correlated with functional quantitative measures of muscle strength: resting RF area on MUS strongly correlated with knee extension quantitative muscle testing (rs 0.76), and contracted area correlated with proximal MMT, knee extension quantitative muscle testing, and CMAS (rs 0.71-0.80). MUS echogenicity correlated with both STIR and T1 MRI (rs 0.43), and T1 MRI correlated inversely with RF contracted area (rs -0.49) on MUS. There were differences in pre- and post-exercise vascular power and colour Doppler on MUS in patients with JDM vs controls, with the percentage change of post-exercise vascular power Doppler lower in JDM compared with controls (7.1% vs 100.0%). These data suggest MUS may be a valuable imaging modality to assess JDM disease activity and damage.

Assessment of naive indolent lymphoma using whole-body diffusion-weighted imaging and T2-weighted MRI: results of a prospective study in 30 patients

BackgroundWe prospectively evaluated the diagnostic utility of whole-body diffusion-weighted imaging with background body signal suppression and T2-weighted short-tau inversion recovery MRI (WB-DWIBS/STIR) for the pretherapeutic staging of indolent lymphoma in 30 patients.MethodsThis prospective study included 30 treatment-naive patients with indolent lymphomas who underwent WB-DWIBS/STIR and conventional imaging workup plus biopsy. The pretherapeutic staging agreement, sensitivity, and specificity of WB-DWIBS/STIR were investigated with reference to the multimodality and multidisciplinary consensus review for nodal and extranodal lesions excluding bone marrow.ResultsIn the pretherapeutic staging, WB-DWIBS/STIR showed very good agreement (κ = 0.96; confidence interval [CI], 0.88–1.00), high sensitivity (93.4–95.1%), and high specificity (99.0–99.4%) for the whole-body regions. These results were similar to those of 18F-FDG-PET/CT, except for the sensitivity for extranodal lesions. For extranodal lesions, WB-DWIBS/STIR showed higher sensitivity compared to 18F-FDG-PET/CT for the whole-body regions (94.9–96.8% vs. 79.6–86.3%, P = 0.058).ConclusionWB-DWIBS/STIR is an effective modality for the pretherapeutic staging of indolent lymphoma, and it has benefits when evaluating extranodal lesions, compared with 18F-FDG-PET/CT.

Is Full Endoscopic Lumbar Discectomy Less Invasive Than Conventional Surgery? A Randomized MRI Study

In the present randomized prospective study, we compared the surgical invasiveness using a quantitative volumetric analysis of postoperative paravertebral muscle signal intensity changes between transforaminal full endoscopic lumbar discectomy (FELD) and open discectomy (OD). We prospectively collected the data from 50 patients with a single-level lumbar foraminal herniation, invalidating radicular pain, and adequate imaging studies available (postoperative magnetic resonance imaging [MRI] <24 hours). These patients had been randomly assigned to FELD (n= 25) or OD (n= 25). Data were collected on age, sex, leg and back pain, complications, and follow-up time. Muscle segmentations were performed manually using 3DSlicer software on postoperative isovolumetric T1-weighted contrast-enhanced and T2-weighted short tau inversion recovery MRI scans. Both sequences were processed using multiplanar reconstruction in orthogonal planes. The clinical and demographic characteristics and volumetric data were then compared between the 2 groups. We found a higher mean volume of paravertebral muscle signal alterations among the OD-treated patients in both T2-weighted short tau inversion recovery MRI (P ≤ 0.001) and T1-weighted contrast-enhanced MRI (P≤ 0.001) scans than among the FELD-treated patients. No differences were found between the median preoperative and postoperative leg pain between the 2 groups (P=1.000). The median scores for postoperative back pain were significantly lower for the FELD group (P ≤ 0.001), as was the median interval from surgery to autonomous mobilization (P= 0.001). We found a significant difference in signal intensity of the paravertebral muscles between the FELD and OD groups, reflective of the minor surgical invasiveness of endoscopic discectomy. FELD resulted in less trauma to the paraspinal muscles, possibly also reducing inflammatory cytokine release and, therefore, is a valuable tool for spinal surgeons.

Pattern of muscle involvement in dermatomyositis – A retrospective analysis using STIR MRI imaging

All patients with suspected Idiopathic Inflammatory Myopathy, over a 4 year period - from August 2014 to August 2018, seen in the departments of Neurology and Rheumatology of Aster Medcity, Kochi, India, were included in the retrospective analysis. 28 patients with DM were selected, who fulfilled the EULAR/ACR classification criteria. Of the 28 patients, 17 patients who had undergone fat suppression sequence, short tau inversion recovery (STIR) MRI muscle imaging were selected. The MRI images were collated and analysed by a single examiner who has over 4 years of experience with muscle MRI. Of the 17 patients with STIR imaging, 12 underwent a whole-body MRI and 5 underwent thigh muscle MRI only. We found that 76% patients were women, with a mean age of 48 yrs. 13 were adult DM, 3 were amyopathic DM and 1 case was a juvenile DM (9 years). The mean disease duration was 10.8 months, and the mean time to MRI from diagnosis and initiation of treatment was 4.7 months except in 3 cases who presented very late (1-2 years after onset). Most muscle changes were patchy, involving muscles asymmetrically. 70% cases showed involvement of lower limb muscles. And 30% showed upper limb and trunk muscle involvement. Paraspinal muscles and shoulder girdles were involved in 50% patients in whom whole-body MRI was performed. Interestingly, the muscles involved the most were the thigh (anterior and posterior compartment muscles), calf muscles, the glutei and pelvic muscles. The pelvic muscles were frequently involved (47%), especially obturator internus and externus.

Quantitative STIR of muscle for monitoring nerve regeneration.

To assess whether short tau inversion recovery (STIR) MRI sequences can provide a tool for monitoring peripheral nerve regeneration, by comparing signal intensity changes in reinnervated muscle over time, and to determine potential clinical time points for monitoring. For this prospective study, 29 patients with complete traumatic transection of the ulnar or median nerves in the forearm were followed up to 45 months postsurgery. Standardized 1.5 Tesla STIR-MRI scans of hand muscles were obtained at fixed time intervals. Muscle signal intensities were measured semi-quantitatively and correlated to functional outcome. For the patients with good function recovery, mean signal intensity ratios of 1.179 ± 0.039, 1.304 ± 0.180, 1.154 ± 0.121, 1.105 ± 0.046 and 1.038 ± 0.047 were found at 1-, 3-, 6-, 9-, and 12-month follow-up, respectively. In the group with poor function recovery, ratios of 1.240 ± 0.069, 1.374 ± 0.144, 1.407 ± 0.127, 1.386 ± 0.128 and 1.316 ± 0.116 were found. Comparing the groups showed significant differences from 6 months onward (P < 0.001), with normalizing signal intensities in the group with good function recovery and sustained elevated signal intensity in the group with poor function recovery. MRI of muscle can be used as a tool for monitoring motor nerve regeneration, by comparing STIR muscle signal intensities over time. A decrease in signal intensity ratio of 50% (as compared to the initial increase) seems to predict good function recovery. Long-term follow-up shows that STIR MRI can be used for at least 15 months after nerve transection to differentiate between denervated and (re)innervated muscles. J. Magn. Reson. Imaging 2016;44:401-410.

Magnetic resonance measurement of muscle T2, fat-corrected T2 and fat fraction in the assessment of idiopathic inflammatory myopathies.

This study examines the utility of MRI, including T2 maps and T2 maps corrected for muscle fat content, in evaluating patients with idiopathic inflammatory myopathy. A total of 44 patients with idiopathic inflammatory myopathy, 18 of whom were evaluated after treatment with rituximab, underwent MRI of the thighs and detailed clinical assessment. T2, fat fraction (FF) and fat corrected T2 (fc-T2) maps were generated from standardized MRI scans, and compared with semi-quantitative scoring of short tau inversion recovery (STIR) and T1-weighted sequences, as well as various myositis disease metrics, including the Physician Global Activity, the modified Childhood Myositis Assessment Scale and the muscle domain of the Myositis Disease Activity Assessment Tool-muscle (MDAAT-muscle). Mean T2 and mean fc-T2 correlated similarly with STIR scores (Spearman rs = 0.64 and 0.64, P < 0.01), while mean FF correlated with T1 damage scores (rs = 0.69, P < 0.001). Baseline T2, fc-T2 and STIR scores correlated significantly with the Physician Global Activity, modified Childhood Myositis Assessment Scale and MDAAT-muscle (rs range = 0.41-0.74, P < 0.01). The response of MRI measures to rituximab was variable, and did not significantly agree with a standardized clinical definition of improvement. Standardized response means for the MRI measures were similar. Muscle T2, fc-T2 and FF measurements exhibit content validity with reference to semi-quantitative scoring of STIR and T1 MRI, and also exhibit construct validity with reference to several myositis activity and damage measures. T2 was as responsive as fc-T2 and STIR scoring, although progression of muscle damage was negligible during the study.

AB1126 Whole-body magnetic resonance imaging in the assessment of disease activity in juvenile dermatomyositis

BackgroundMagnetic resonance imaging (MRI) has been suggested as a valuable technique for diagnosis of myositis because of its high sensitivity to the presence of inflammation. So far all MRI studies...

PWE-067 MRI to distinguish hidradenitis suppurativa from perianal Crohn's disease

IntroductionHidradenitis suppurativa is a chronic inflammatory disease of apocrine gland-bearing skin. It has a predilection for the ano-genital skin and is characterised clinically by inflammatory abscesses and sinus tract formation....

The use of joint-specific and whole-body MRI in osteonecrosis: a study in patients with juvenile systemic lupus erythematosus

This study aimed to estimate the prevalence of osteonecrosis (ON) in juvenile systemic lupus erythematosus (SLE) patients using joint-specific and whole-body MRI; to explore risk factors that are associated with the development of ON; and to evaluate prospectively patients 1 year after initial imaging. Within a 2 year period, we studied 40 juvenile SLE patients (aged 8-18 years) with a history of steroid use of more than 3 months duration. Risk factors including disease activity, corticosteroid use, vasculitis, Raynaud's phenomenon and lipid profile were evaluated. All patients underwent MRI of the hips, knees and ankles using joint-specific MRI. Whole-body STIR (short tau inversion recovery) MRI was performed in all patients with ON lesions. Osteonecrosis was identified in 7 patients (17.5 %) upon joint-specific MRI. Whole-body STIR MRI detected ON in 6 of these 7 patients. There was no significant difference between the ON and non-ON groups in the risk factors studied. One patient had pre-existing symptomatic ON. At 1 year follow-up, the ON lesions had resolved in one patient, remained stable in four and decreased in size in two. No asymptomatic patients with ON developed clinical manifestations. Whole-body STIR MRI may be useful in detecting ON lesions in juvenile SLE patients but larger studies are needed to define its role.

Clinical impact of short tau inversion recovery MRI on staging and management in patients with cervical lymph node metastases of head and neck squamous cell carcinomas

We investigated the incremental diagnostic value of short tau inversion recovery (STIR) MRI to detect cervical nodal metastases in head and neck squamous cell carcinoma. Thirty-six patients with cervical nodal metastases underwent MRI preceding neck dissection. Two readers evaluated MRI versus MRI with STIR. Level-based analysis was performed: interobserver agreements (kappa) for detecting normal and metastatic lymph nodes; sensitivities and specificities for detecting at least 1 metastatic lymph node per level; linear regression analysis to determine performances of MRI with STIR in detecting correct numbers of normal and metastatic lymph nodes. Histopathology was the reference standard. One hundred eighty neck levels were evaluated. MRI with STIR showed better kappas for metastatic and normal lymph nodes, was more accurate to estimate numbers of metastatic and normal lymph nodes, and showed improvement of sensitivities and specificities. Incorporation of STIR into the conventional MR protocol significantly improves the detection of cervical lymph node metastases.

The Effectiveness of 18F-FDG PET/CT Combined with STIR MRI for Diagnosing Nodal Involvement in the Thorax

The purpose of this study was to compare the efficacy of short-tau inversion-recovery (STIR) MRI and 18F-FDG PET/CT for the detection of metastasis in mediastinal and hilar lymph nodes in patients with lung cancer. Ninety-three patients with known or suspected lung cancer with mediastinal and hilar lymph node swelling underwent STIR MRI and 18F-FDG PET/CT examinations. STIR MRI scans were obtained with a 2% copper sulfate phantom placed along the back of each patient, with the lymph node-to-phantom ratio calculated for quantitative analysis. For qualitative analysis, the results of all STIR MRI scans were evaluated using a 5-point visual scoring system. To evaluate the diagnostic capabilities of STIR MRI and 18F-FDG PET/CT, we used receiver-operating-characteristic curve analysis to determine the optimal thresholds for the lymph node-to-phantom ratio, visual score, and maximal standardized uptake value. Further, the capability of each to determine N-stage was compared in each patient using the McNemar test. A total of 137 lymph nodes (82 malignant lesions, 55 benign lesions) were analyzed. When optimal threshold values were adopted, the quantitative and qualitative sensitivity, specificity, and accuracy of STIR MRI were not significantly different from those of 18F-FDG PET/CT. However, 18F-FDG PET/CT in combination with qualitative STIR MRI analysis had a significantly higher capability to detect nodal involvement on an individual-patient basis (96.9% specificity, 90.3% accuracy) than did 18F-FDG PET/CT alone (65.6% specificity, 81.7% accuracy). We found that the diagnostic capability of STIR MRI was not significantly different from that of 18F-FDG PET/CT. However, when those methods were combined, the diagnostic capability for N-staging was significantly improved.

STIR(ing) appearance of rhabdomyolysis.

A 30-year-old man was admitted unconscious to a peripheral hospital after consuming 120 mg of methadone to celebrate his release from prison. On arrival his creatinine was 1.93 mg/dl and his creatine kinase 68645 (IU/l). After reversal of his opiate intoxication, he began complaining of burning pain and weakness in both legs. Over the next 36 h his creatinine increased to 11.4 mg/dl with worsening metabolic acidosis, and he became anuric. He was transferred to our unit for dialysis. Due to persistent bilateral leg pain and a right-sided foot-drop an MRI (Figure ​(Figure1)1) was performed, which demonstrated bilateral gluteal oedema (panel C, arrows) consistent with rhabdomyolysis, causing compression of the right sciatic nerve at the sciatic notch (panel D, arrow). He required seven dialysis sessions before his renal function began to recover, and when reviewed 1 month post-discharge his creatinine was 1.5 mg/dl and he was receiving physiotherapy for a persistent foot drop. Fig. 1 Coronal (A and C) and axial (B and D) short tau-inversion recovery MRI sequences from a normal individual on the left (A and B) and showing high signal intensity in the glutei bilaterally in the patient on the right (C and D). Rhabdomyolysis describes the breakdown of striated muscle fibres, which results in the release of intracellular contents [1]. Of the many compounds liberated, myoglobin in particular is implicated in the development of renal failure, through precipitation and obstruction of tubules and free radical generation [2]. MRI has become the imaging modality of choice to define the extent of muscle damage in rhabdomyolysis, especially when fasciotomies are considered [3]. Short tau-inversion-recovery (STIR) sequences provide excellent differentiation between affected (hyperintense signal) and unaffected tissues with greater sensitivity than other imaging techniques and without exposure to radiation. Conflict of interest statement. None declared.

Mastocytosis: magnetic resonance imaging patterns of marrow disease.

To report the bone marrow MRI findings of patients with mastocytosis and correlate them with clinical, pathologic, and radiographic features. Eighteen patients with mastocytosis had T1-weighted spin echo and short tau inversion recovery MRI of the pelvis at 0.5 T. In each patient the MR pattern of marrow disease was classified according to intensity and uniformity and was correlated with the clinical category of mastocytosis, bone marrow biopsy results, and radiographic findings. Two patients had normal MRI scans and normal bone marrow biopsies. One patient had a normal MRI scan and a marrow biopsy consistent with mastocytosis. Fifteen patients had abnormal MRI scans and abnormal marrow biopsies. There were several different MR patterns of marrow involvement; none was specifically associated with any given clinical category of mastocytosis. Fifteen of the 18 patients had radiographs of the pelvis; of those, 13 with abnormal MRI scans and abnormal marrow biopsies had the following radiographic findings: normal (nine); sclerosis (three); diffuse osteopenia (one). While radiographs are very insensitive for the detection of marrow abnormalities in mastocytosis, MRI is very sensitive and may display several different patterns of marrow involvement.