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BACKGROUND: Assessment of the activity of Graves' ophthalmopathy (GO) is difficult. Existing methods need improvement. PURPOSE: Investigate the application of multiparametric magnetic resonance imaging (MRI) in GO. STUDY TYPE: Retrospective. POPULATION: A total of 235 GO patients (age: 38.8 ± 13.4 years; 90 male; 96 active patients). FIELD STRENGTH/SEQUENCE: Short-tau inversion recovery (STIR) fast spin echo, multiecho spin echo T2 mapping and 3D T1-weighted fast field echo sequences at 3.0 T. ASSESSMENT: Two physicians assessed the mean and maximum signal intensity ratio of extraocular muscles to white matter (SIR), T2 relaxation time (T2RT), extraocular muscle area (EMA), fat fraction (FF), retrobulbar fat volume (RFV), and extraocular muscle volume (EMV). Clinical activity score (CAS) ⧠3 was in active stage. STATISTICAL TESTS: The optimal cut-off point of diagnostic efficacy was selected using receiver operating characteristic (ROC) curve analysis and evaluated using area under the curve (AUC), compared using Student's t test, analysis of variance or Kruskal-Wallis H test. The correlation used Pearson correlation analysis. The discriminant equation used a binary logistic regression analysis. P < 0.05 was considered statistically significant. RESULTS: The SIRmean, SIRmax, T2RTmean, T2RTmax, EMA, and EMV in active GO patients were significantly higher than those in inactive and were positively correlated with CAS (r = 0.276, 0.228, 0.438, 0.388, 0.502, and 0333, respectively). The FFmax of active patients was significantly lower than that of inactive patients and was negatively correlated with CAS (r = -0.44). Logistic regression analysis indicated that T2RTmean was independently associated with GO active periods and had good diagnostic performance (area under ROC curve = 0.736, sensitivity 70.7%, specificity 69.3%). T2RTmean ⧠74.295 could be a diagnostic cut-off for judging GO activity (sensitivity 55.3%). CONCLUSION: SIR, T2RT, EMV, and FF can quantitatively assess the activity and severity of GO and can potentially provide a basis for clinical judgment and selection of treatment options. EVIDENCE LEVEL: 4. TECHNICAL EFFICACY: Stage 2.
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Oftalmopatia de Graves , Imageamento por Ressonância Magnética Multiparamétrica , Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Estudos Retrospectivos , Oftalmopatia de Graves/diagnóstico por imagem , Oftalmopatia de Graves/tratamento farmacológico , Músculos Oculomotores/diagnóstico por imagem , Músculos Oculomotores/patologia , Imageamento por Ressonância Magnética/métodosRESUMO
Magnetic resonance imaging (MRI) can provide accurate and non-invasive diagnoses of lower extremity injuries in athletes. Sport-related injuries commonly occur in and around the knee and can affect the articular cartilage, patellar tendon, hamstring muscles, and bone. Sports medicine physicians utilize MRI to evaluate and diagnose injury, track recovery, estimate return to sport timelines, and assess the risk of recurrent injury. This article reviews the current literature and describes novel developments of quantitative MRI tools that can further advance our understanding of sports injury diagnosis, prevention, and treatment while minimizing injury risk and rehabilitation time. Innovative approaches for enhancing the early diagnosis and treatment of musculoskeletal injuries in basketball players span a spectrum of techniques. These encompass the utilization of T2 , T1ρ , and T2 * quantitative MRI, along with dGEMRIC and Na-MRI to assess articular cartilage injuries, 3D-Ultrashort echo time MRI for patellar tendon injuries, diffusion tensor imaging for acute myotendinous injuries, and sagittal short tau inversion recovery and axial long-axis T1 -weighted, and 3D Cube sequences for bone stress imaging. Future studies should further refine and validate these MR-based quantitative techniques while exploring the lifelong cumulative impact of basketball on players' knees. LEVEL OF EVIDENCE: 5 TECHNICAL EFFICACY: Stage 2.
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OBJECTIVE: Quantitatively staging TAO using MRI remains limited. Our study aims to identify the cut-off signal intensity value for staging TAO using STIR sequence scan. METHODS: Between June 2018 and July 2020, a number of 51 patients with TAO (102 eyes) and 19 volunteer controls (38 eyes) were recruited. The clinical and biochemical parameters were measured in each patient. Disease activity was diagnosed based on the Clinical Activity Score (CAS). The signal intensities of extraocular muscles were scanned using short-tau inversion recovery (STIR) sequences from MRI. RESULTS: Compared to the inactive TAO patients and the controls, the signal intensity ratios (SIRs) of the superior rectus, inferior rectus, medial rectus, lateral rectus on STIR images were significantly increased in the active TAO patients. After adjustment for age and smokers, the SIRs of four extraocular muscles showed strong associations with CAS. By receiver operator characteristic (ROC) curve analysis, all four muscle SIRs demonstrated good efficiency for predicting disease activity [area under curve (AUC) 0.75-0.83, all P < 0.01]. The identified cut-off SIR values were further validated in a new group of TAO patients (30 eyes) enrolled between September 2020 and January 2021. The cut-off SIR value of > 2.9 in the inferior rectus showed optimal diagnostic value for staging the active TAO. CONCLUSIONS: the signal intensity of extraocular muscles on STIR sequence was a good predictor for TAO activity. A cut-off SIR value of > 2.9 in the inferior rectus could be applied to evaluate the active stage of TAO.
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Oftalmopatia de Graves/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Músculos Oculomotores/diagnóstico por imagem , Adulto , Estudos de Casos e Controles , Descompressão Cirúrgica , Progressão da Doença , Feminino , Glucocorticoides/uso terapêutico , Oftalmopatia de Graves/fisiopatologia , Oftalmopatia de Graves/terapia , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
PURPOSE: To generate short tau, or short inversion time (TI), inversion recovery (STIR) images from three multi-contrast MR images, without additional scanning, using a deep neural network. METHODS: For simulation studies, we used multi-contrast simulation images. For in-vivo studies, we acquired knee MR images including 288 slices of T1 -weighted (T1 -w), T2 -weighted (T2 -w), gradient-recalled echo (GRE), and STIR images taken from 12 healthy volunteers. Our MR image synthesis method generates a new contrast MR image from multi-contrast MR images. We used a deep neural network to identify the complex relationships between MR images that show various contrasts for the same tissues. Our contrast-conversion deep neural network (CC-DNN) is an end-to-end architecture that trains the model to create one image from three (T1 -w, T2 -w, and GRE images). We propose a new loss function to take into account intensity differences, misregistration, and local intensity variations. The CC-DNN-generated STIR images were evaluated with four quantitative evaluation metrics, including mean squared error, peak signal-to-noise ratio (PSNR), structural similarity (SSIM), and multi-scale SSIM (MS-SSIM). Furthermore, a subjective evaluation was performed by musculoskeletal radiologists. RESULTS: Our method showed improved results in all quantitative evaluations compared with other methods and received the highest scores in subjective evaluations by musculoskeletal radiologists. CONCLUSION: This study suggests the feasibility of our method for generating STIR sequence images without additional scanning that offered a potential alternative to the STIR pulse sequence when additional scanning is limited or STIR artifacts are severe.
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Artefatos , Imageamento por Ressonância Magnética , Humanos , Razão Sinal-RuídoRESUMO
OBJECTIVE: To investigate the association of spinal inflammation on MRI in patients with various clinical, functional and radiological outcomes in patients with axial spondyloarthritis (SpA). METHODS: Three hundred and ninety-seven participants with axial SpA and back pain were recruited from 10 rheumatology centres. Clinical, biochemical and radiological parameters were collected and participants underwent MRI of the spine. MRI features including inflammatory lesions of facet joints and costovertebral joints, corner inflammatory lesions, and spondylitis were assessed. BASFI, Bath Ankylosing Spondylitis Disease Activity Index, Bath Ankylosing Spondylitis Global Index, BASMI and modified Stoke Ankylosing Spondylitis Spinal Score were measured. Multivariate linear regression models were used to determine the associations between MRI parameters and various clinical, functional and radiological outcomes. RESULTS: BASMI and BASFI correlated well with inflammatory features in spinal MRI. Multivariate analysis showed that lumbar facet joint inflammation was independently associated with BASMI (regression coefficient (ß) = 0.12, P < 0.001), lumbar spinal flexion (ß = 0.13, P = 0.00), lateral spinal flexion (ß = 0.09, P = 0.04), tragus-to-wall distance (ß = 0.16, P < 0.001) and BASFI (ß = 0.14, P = 0.01). Costovertebral joint inflammation was also associated with BASMI (ß = 0.08, P = 0.05). CONCLUSION: Inflammatory lesions of facet and costovertebral joints in MRI are associated with restriction in spinal mobility and functional impairment. These important yet commonly overlooked lesions should be reviewed in clinical practice in patients with SpA.
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Inflamação , Vértebras Lombares/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Amplitude de Movimento Articular , Coluna Vertebral , Espondilite Anquilosante , Articulação Zigapofisária/diagnóstico por imagem , Correlação de Dados , Feminino , Estado Funcional , Humanos , Inflamação/diagnóstico , Inflamação/fisiopatologia , Masculino , Pessoa de Meia-Idade , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/patologia , Coluna Vertebral/fisiopatologia , Espondilite Anquilosante/diagnóstico , Espondilite Anquilosante/fisiopatologiaRESUMO
BACKGROUND: Modic Changes (MCs, magnetic resonance imaging (MRI) signal changes in the vertebral bone marrow extending from the vertebral endplate) may represent a subgroup of nonspecific chronic low back pain that could benefit from a specific management. The primary aim was to compare clinical characteristics between patients with type 1 versus type 2 MCs. The secondary aim was to explore associations between clinical characteristics and MC related short tau inversion recovery (STIR) signals. METHODS: This cross-sectional study used baseline data prospectively collected between 2015 and 2017 on the 180 patients included in the AIM-study (Antibiotics In Modic changes), a randomized controlled trial in a Norwegian hospital out-patient setting of patients with chronic low back pain, a lumbar disc herniation within the last 2 years, low back pain intensity score ≥ 5 (on a 0-10 scale) and current type 1 or type 2 MCs at the previously herniated lumbar disc level. We used prespecified clinical characteristics including self-report measures, physiologic measures and functional measures from clinical history and examination. The diagnostic accuracy of various clinical characteristics to discriminate between patients with type 1 MCs (with or without additional type 2 MCs) and patents with type 2 MCs only (not type 1) were assessed by calculating the area under the receiver-operating curve. We assessed the correlations of clinical characteristics with details of MC related STIR signal increase. RESULTS: No clinical characteristic differed between patients with type 1 (n = 118) versus type 2 (but not type 1) (n = 62) MCs. The clinical characteristics showed no/minor differences or no/weak correlations with MC related STIR signal increase. Patients with a positive Springing test (at any lumbar level) had slightly less volume of STIR signal increase than those with a negative test (mean difference 1.3 on a 0-48 scale, 95% CI 0.3 to 2.3). CONCLUSION: Clinical characteristics were similar for patients with type 1 MCs and patients with type 2 MCs, and showed no clinically relevant correlations with MC related STIR signal increase. TRIAL REGISTRATION: ClinicalTrials.gov NCT02323412, First registered 23 December 2014.
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Antibacterianos/administração & dosagem , Medula Óssea/efeitos dos fármacos , Dor Crônica/tratamento farmacológico , Deslocamento do Disco Intervertebral/tratamento farmacológico , Dor Lombar/tratamento farmacológico , Vértebras Lombares/efeitos dos fármacos , Imageamento por Ressonância Magnética/métodos , Adulto , Antibacterianos/efeitos adversos , Medula Óssea/diagnóstico por imagem , Dor Crônica/diagnóstico por imagem , Dor Crônica/fisiopatologia , Estudos Transversais , Método Duplo-Cego , Feminino , Humanos , Deslocamento do Disco Intervertebral/diagnóstico por imagem , Deslocamento do Disco Intervertebral/fisiopatologia , Dor Lombar/diagnóstico por imagem , Dor Lombar/fisiopatologia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Noruega , Medição da Dor , Inquéritos e Questionários , Fatores de Tempo , Resultado do TratamentoRESUMO
BACKGROUND: Myocardial edema in acute myocardial infarction (AMI) is commonly imaged using dark-blood short tau inversion recovery turbo spin echo (STIR-TSE) cardiovascular magnetic resonance (CMR). The technique is sensitive to cardiac motion and coil sensitivity variation, leading to myocardial signal nonuniformity and impeding reliable depiction of edematous tissues. T2-prepared balanced steady state free precession (T2p-bSSFP) imaging has been proposed, but its contrast is low, and averaging is commonly needed. T2 mapping is useful but requires a long scan time and breathholding. We propose here a single-shot magnetization prepared sequence that increases the contrast between edema and normal myocardium and apply it to myocardial edema imaging. METHODS: A magnetization preparation module (T2STIR) is designed to exploit the simultaneous elevation of T1 and T2 in edema to improve the depiction of edematous myocardium. The module tips magnetization down to the -z axis after T2 preparation. Transverse magnetization is sampled at the fat null point using bSSFP readout and allows for single-shot myocardial edema imaging. The sequence (T2STIR-bSSFP) was studied for its contrast behavior using simulation and phantoms. It was then evaluated on 7 healthy subjects and 7 AMI patients by comparing it to T2p-bSSFP and T2 mapping using the contrast-to-noise ratio (CNR) and the contrast ratio as performance indices. RESULTS: In simulation and phantom studies, T2STIR-bSSFP had improved contrast between edema and normal myocardium compared with the other two edema imaging techniques. In patients, the CNR of T2STIR-bSSFP was higher than T2p-bSSFP (5.9 ± 2.6 vs. 2.8 ± 2.0, P < 0.05) but had no significant difference compared with that of the T2 map (T2 map: 6.6 ± 3.3 vs. 5.9 ± 2.6, P = 0.62). The contrast ratio of T2STIR-bSSFP (2.4 ± 0.8) was higher than that of the T2 map (1.3 ± 0.1, P < 0.01) and T2p-bSSFP (1.4 ± 0.5, P < 0.05). CONCLUSION: T2STIR-bSSFP has improved contrast between edematous and normal myocardium compared with commonly used bSSFP-based edema imaging techniques. T2STIR-bSSFP also differentiates between fat that was robustly suppressed and fluids around the heart. The technique is useful for single-shot edema imaging in AMI patients.
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Edema Cardíaco/diagnóstico por imagem , Imageamento por Ressonância Magnética , Adulto , Idoso , Estudos de Casos e Controles , Simulação por Computador , Meios de Contraste/administração & dosagem , Feminino , Gadolínio DTPA/administração & dosagem , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética/instrumentação , Masculino , Pessoa de Meia-Idade , Modelos Cardiovasculares , Imagens de Fantasmas , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Adulto JovemRESUMO
When medically intractable epilepsy is multifocal or focal but poorly localized, neuromodulation can be useful therapy. One such technique is deep brain stimulation (DBS) targeting the anterior nucleus of the thalamus (ANT). Unfortunately, the ANT is difficult to visualize in standard MRI sequences and its indirect targeting is difficult because of thalamic variability and atrophy in patients with epilepsy. The following study describes the novel use of the fast gray matter acquisition T1 inversion recovery (FGATIR) MRI sequence to delineate the mammillothalamic tract for direct targeting of the ANT through visualizing the termination of the mammillothalamic tract in the ANT. The day prior to surgery in a 19-year-old, right-handed woman with a 5-year history of epilepsy, MRI was performed on a 3-T Siemens Prisma scanner (Siemens AG, Healthcare Sector) using a 64-channel head and neck coil. As part of the imaging protocol, noncontrast magnetization-prepared rapid gradient echo (MP-RAGE) and diffusion tensor imaging (DTI) sequences were obtained for targeting purposes. The ANT was directly targeted using the FGATIR sequence, and bilateral Medtronic 3389 leads were placed. At the last follow-up (2 months), the patient reported an approximate 75% decrease in seizure frequency, as well as a decrease in seizure severity.
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Núcleos Anteriores do Tálamo , Estimulação Encefálica Profunda , Epilepsia/terapia , Substância Cinzenta/cirurgia , Adulto , Estimulação Encefálica Profunda/métodos , Imagem de Tensor de Difusão/métodos , Eletrodos Implantados , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Substância BrancaRESUMO
OBJECTIVE: This study aimed to compare the signal-to-noise ratios (SNRs) and apparent diffusion coefficients (ADCs) obtained using two fat suppression techniques in breast diffusion-weighted imaging (DWI) of a phantom. MATERIALS AND METHODS: The breast phantom comprised agar gels with four different concentrations of granulated sugar (samples 1, 2, 3, and 4). DWI with short tau inversion recovery (STIR-DWI) and that with spectral attenuated inversion recovery (SPAIR-DWI) were performed using 3.0-T magnetic resonance imaging, and the obtained SNRs and ADCs were compared. ADCs were also compared between the right and left breast phantoms. RESULTS: For samples 3 and 4, SNRs obtained using STIR-DWI were lower than those obtained using SPAIR-DWI. For samples 2, 3, and 4, overall ADCs obtained using STIR-DWI were significantly higher than those obtained using SPAIR-DWI (p < 0.001 for all), although no significant difference was observed for sample 1 (p = 0.62). STIR-DWI shows a positive bias and wide limits of agreement in Bland-Altman plot. The coefficients of variance of overall ADCs were good in STIR-DWI and SPAIR-DWI. For all samples, STIR-DWI demonstrated slightly larger percentage differences in ADCs between the right and left phantoms than SPAIR-DWI. CONCLUSION: SNRs and ADCs obtained using STIR-DWI are influenced by the T 1 value; a shorter T 1 value decreases SNRs, overestimates ADCs, and induces the measurement error in ADCs. STIR-DWI showed a larger difference in ADCs between the right and left phantoms than SPAIR-DWI.
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Imagem de Difusão por Ressonância Magnética , Processamento de Imagem Assistida por Computador , Imagens de Fantasmas , Razão Sinal-Ruído , Mama/diagnóstico por imagemRESUMO
Spine stereotactic radiosurgery (SSRS) has recently emerged as an increasingly effective treatment for spinal metastases. Studies performed over the past decade have examined the role of imaging in the diagnosis of metastases, as well as treatment response following SSRS. In this paper, the authors describe and review the utility of several imaging modalities in the diagnosis of spinal metastases and monitoring of their response to SSRS. Specifically, we review the role of CT, MRI, and positron emission tomography (PET) in their ability to differentiate between osteoblastic and osteolytic lesions, delineation of initial bony pathology, detection of treatment-related changes in bone density and vertebral compression fracture after SSRS, and tumor response to therapy. Validated consensus guidelines defining the imaging approach to SSRS are needed to standardize the diagnosis and treatment response assessment after SSRS. Future directions of spinal imaging, including advances in targeted tumor-specific molecular imaging markers demonstrate early promise for advancing the role of imaging in SSRS.
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Neuroimagem , Radiocirurgia/métodos , Neoplasias da Coluna Vertebral/diagnóstico por imagem , Neoplasias da Coluna Vertebral/cirurgia , Resultado do Tratamento , Feminino , Fraturas por Compressão , Humanos , Masculino , Reprodutibilidade dos Testes , Neoplasias da Coluna Vertebral/secundárioRESUMO
Osteonecrosis of the femoral head is considered to occur early during the course of corticosteroid treatment. However, it remains unclear exactly how early it can develop after initiation of corticosteroid treatment. We report a case of osteonecrosis of the femoral head in which abnormal findings were observed on short-tau inversion recovery (STIR) sequence image performed 2 weeks and 4 days after initiation of high-dose corticosteroid therapy. A 45-year-old man with hemophagocytic syndrome was started on prednisolone, with a maximum dose of 40 mg/day. On day 13 after initiation of this corticosteroid therapy, he transiently experienced left hip pain with no apparent cause. STIR sequence image 5 days after the onset of pain revealed high-intensity bone marrow lesions at the femoral neck of both hips. At 3 months after initiation of corticosteroid therapy, T1-weighted magnetic resonance imaging revealed concave-shaped low-intensity bands, which corresponded to the preceding high-intensity lesions on both hips. Because of the subsequent progression to collapse of the left femoral head, he underwent prosthetic replacement surgery. The high-intensity lesions on STIR sequence image indicate the possibility that osteonecrosis can occur within 3 weeks after initiation of high-dose corticosteroid therapy.
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Medula Óssea/efeitos dos fármacos , Necrose da Cabeça do Fêmur/induzido quimicamente , Cabeça do Fêmur/efeitos dos fármacos , Glucocorticoides/efeitos adversos , Linfo-Histiocitose Hemofagocítica/tratamento farmacológico , Imageamento por Ressonância Magnética , Prednisolona/efeitos adversos , Artroplastia de Quadril , Medula Óssea/patologia , Progressão da Doença , Diagnóstico Precoce , Cabeça do Fêmur/diagnóstico por imagem , Cabeça do Fêmur/patologia , Cabeça do Fêmur/cirurgia , Necrose da Cabeça do Fêmur/diagnóstico por imagem , Necrose da Cabeça do Fêmur/patologia , Necrose da Cabeça do Fêmur/cirurgia , Glucocorticoides/administração & dosagem , Humanos , Linfo-Histiocitose Hemofagocítica/diagnóstico , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prednisolona/administração & dosagem , Radiografia , Fatores de Tempo , Resultado do TratamentoRESUMO
OBJECT High-resolution magnetic resonance imaging (MRI) can distinguish between intraneural ganglion cysts and paralabral (extraneural) cysts at the glenohumeral joint. Suprascapular intraneural ganglion cysts share the same pathomechanism as their paralabral counterparts, emanating from a tear in the glenoid labrum. The authors present 2 cases to demonstrate that the identification and arthroscopic repair of labral tears form the cornerstone of treatment for intraneural ganglion cysts of the suprascapular nerve. METHODS Two patients with suprascapular intraneural ganglion cysts were identified: 1 was recognized and treated prospectively, and the other, previously reported as a paralabral cyst, was identified retrospectively through the reinter-pretation of high-resolution MR images. RESULTS Both patients achieved full functional recovery and had complete radiological involution of the intraneural ganglion cysts at the 3-month and 12-month follow-ups, respectively. CONCLUSIONS Previous reports of suprascapular intraneural ganglion cysts described treatment by an open approach to decompress the cysts and resect the articular nerve branch to the glenohumeral joint. The 2 cases in this report demonstrate that intraneural ganglion cysts, similar to paralabral cysts, can be treated with arthroscopic repair of the glenoid labrum without resection of the articular branch. This approach minimizes surgical morbidity and directly addresses the primary etiology of intraneural and extraneural ganglion cysts.
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Artroscopia/métodos , Cistos Glanglionares/cirurgia , Articulação do Ombro/cirurgia , Adulto , Feminino , Humanos , Imageamento por Ressonância MagnéticaRESUMO
Neurogenic thoracic outlet syndrome (nTOS) is caused by compression of the brachial plexus as it traverses from the thoracic outlet to the axilla. Diagnosing nTOS can be difficult because of overlap with other complex pain and entrapment syndromes. An nTOS diagnosis is made based on patient history, physical exam, electrodiagnostic studies, and, more recently, interpretation of MR neurograms with tractography. Advances in high-resolution MRI and tractography can confirm an nTOS diagnosis and identify the location of nerve compression, allowing tailored surgical decompression. In this report, the authors review the current diagnostic criteria, present an update on advances in MRI, and provide case examples demonstrating how MR neurography (MRN) can aid in diagnosing nTOS. The authors conclude that improved high-resolution MRN and tractography are valuable tools for identifying the source of nerve compression in patients with nTOS and can augment current diagnostic modalities for this syndrome.
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Imageamento por Ressonância Magnética , Síndrome do Desfiladeiro Torácico/diagnóstico , Descompressão Cirúrgica , Feminino , Humanos , Pessoa de Meia-Idade , Síndrome do Desfiladeiro Torácico/cirurgiaRESUMO
BACKGROUND: Perianal abscess is a clinical infective and/or inflammatory collection in the perianal region, one entity of a large group of anal and perianal disorders. Perianal abscesses are often seen as a complication of grade 2 and grade 4 perianal fistulas from St. James's University Hospital classification. Several imaging modalities have been tried in the past for adequate assessment of perianal abscess with contrast-enhanced magnetic resonance imaging (CE-MRI) providing the most accurate results. Diffusion-weighted imaging (DWI) is an emerging sequence that can provide comparable results to CE-MRI in diagnosing and characterizing perianal abscess. The main objective of this study is to assess the role of DWI in adequate identification and assessment of perianal abscess and compare the final results with contrast-enhanced images. METHODS: Twenty patients with complicated perianal fistula with clinically suspected perianal abscess were evaluated with DWI and CE-MRI. This study was a comparative cross-sectional study conducted in the Department of Radiodiagnosis and Imaging, All India Institute of Medical Sciences, Bhopal, India. Chi-square test was done to find the association between categorical variables. Kappa test was used to find the agreement between two different tests. Receiver operating characteristics (ROC) analysis was done to estimate the area under the curve in predicting the outcome. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy were used to measure the validity of the tests. RESULTS: DWI is a very sensitive MRI sequence and is equivalent to CE-MRI to detect the location and analyzing the loco-regional extent of abscess in complicated perianal fistula cases. DWI is also very sensitive and superior to T2 short tau inversion recovery (STIR) in differentiating perianal abscess from perianal inflammation without abscess. CONCLUSION: DWI can be used as an alternative to post-contrast fat-suppressed MRI in precisely defining the location and extent of anal and perianal abscesses and disease activity in complicated fistula cases.
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BACKGROUND: Perianal fistula is clinically diagnosed and commonly characterized using magnetic resonance imaging (MRI). Diffusion-weighted imaging (DWI) and T2-weighted imaging are emerging techniques that can obviate the need for contrast injection in cases where contrast administration is not feasible or contraindicated. The main objective of our study was to compare the efficacy of the combination of DWI and T2 STIR (short tau inversion recovery) imaging with contrast-enhanced MRI for the diagnosis and characterization of perianal fistula. METHODS: Sixty-nine patients with clinical perianal fistula with at least one external opening were evaluated with DWI, T2 STIR, and contrast MRI. A comparative cross-sectional study was conducted in the Department of Radiodiagnosis and Imaging, All India Institute of Medical Sciences, Bhopal, India. The chi-square test was done to find the association between categorical variables. The Kappa test was done to estimate the agreement between two different tests in measuring the outcome. The validity of tests was measured using sensitivity, specificity, positive predictive value, negative predictive value, and accuracy. RESULTS: The combination of DWI and T2 STIR is equivalent to contrast-enhanced MRI in the evaluation of primary and complicated perianal fistula. The combination of DWI and T2 STIR is superior to DWI alone in the classification and characterization of perianal fistula. However, DWI is superior to T2 STIR in differentiating perianal inflammation with abscess from perianal inflammation without abscess and can be used as an alternative to post-contrast fat-suppressed T1-WI in the detection of perianal abscesses and disease activity. CONCLUSION: DWI can be used as an adjunct to T2 STIR, and the combination of DWI and T2 STIR can replace the post-contrast fat-suppressed T1 MRI sequence in the classification and characterization of perianal fistula.
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A diffusion-weighted whole body imaging with background body signal suppression (DWIBS) is usually imaged as a whole body with Transverse (Tra). However, Tra has a large number of stations and a larger number than Coronal (Cor), so the scan time is longer. There are also drawbacks, such as signal unevenness between series. It is known that the effect of distortion is large in Cor. There is no report on it in Sagittal (Sag). Therefore, in this study, we focused on Sag and examined the imaging time, image distortion, fat suppression effect, and continuity between stations. In the examination by the phantom, the scan time was the shortest for Cor and the longest for Sag. In the strain evaluation, the effect of strain could be suppressed compared to Cor by using a rectangle field of view (FOV) in the anterior to posterior (AP) direction in Tra and Sag. There was no difference in the fat suppression effect depending on the imaging direction. Similar results were obtained in a study of 10 healthy volunteers, with Sag having the best continuity between stations.
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Imagem de Difusão por Ressonância Magnética , Imagens de Fantasmas , Imagem Corporal Total , Humanos , Imagem de Difusão por Ressonância Magnética/métodos , Imagem Corporal Total/métodos , Masculino , Adulto , FemininoRESUMO
There was tremendous increase in the number of cases of mucormycosis among patients affected by coronavirus disease 2019 (COVID-19) during the second wave of pandemic in South Asian countries. This invasive fungal infection primarily affects paranasal sinuses and can have orbito-facial and intracranial extension. We are presenting the radiological findings of invasive mucormycosis with pathological and clinical outcome correlation. It is important for radiologists to have the knowledge of various presentations of this opportunistic infection for early diagnosis and helping clinicians in planning the appropriate line of management. The study also emphasizes on the correlation between the extent of involvement with clinical outcome and we proposed a magnetic resonance imaging (MRI) based scoring system to standardize and prognosticate the patients affected with mucormycosis. MATERIALS AND METHODS: We utilized GE 1.5 tesla, 16-channeled MRI machine for scanning the clinically suspected mucormycosis patients and did plain and contrast study of the paranasal sinuses, orbito-facial study and included brain as and when required. Images were acquired in axial, coronal, and sagittal planes using T1, T2, and fat-saturated short tau inversion recovery sequences (STIR), fat-saturated contrast sequences for better evaluation of the extent of the disease. Diffusion-weighted sequence was also acquired to detect ischemic changes in optic nerve or brain parenchyma. Contrast study was used to detect any major vessel occlusion or cavernous sinus thrombosis in the study population. RESULTS: Total number of cases (n) included in the study were 32. The mean age group was 41-50 years with the median age was 47 years. Out of 32 cases (n=32), in 16 cases (50%) the disease was limited only to the paranasal sinuses and in remaining 16 (50%) cases, disease has spread to other regions such as orbits, facial soft tissues, optic nerve, and brain parenchyma. All the 18 cases with Mild score (MRI ROCM score 1-3) survived and all those with severe score (2 cases) (MRI ROCM score 7-10) did not survive. CONCLUSION: During the second wave of COVID-19 pandemic, we observed a signiï¬cant rise in acute invasive mucormycosis infection primarily involving the paranasal sinuses and spread to orbito-facial, cerebral parenchyma causing related complications and hence increased morbidity and death. Radiologically, using MRI, it was effectively possible to detect early extrasinonasal spread and other fatal complications thereby guiding the physicians and surgeons in the proper early aggressive management of the disease. Here, we have described the radiological characteristics of paranasal sinus mucormycosis and its spread to other regions. We also proposed an MRI-based Scoring System for standardized assessment of the disease severity. We observed in our study that the extent of disease on MRI is directly correlating with mortality.
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BACKGROUND: Agenesis of the corpus callosum (ACC) is a rare hereditary nervous system defect present at birth. ACC is an uncommon condition that is unrepresentative in the general population because some cases do not present with any identifiable symptoms in the early stage. CASE REPORT: We present a case of ACC in a two-month-old male patient who was diagnosed after birth. Although the initial brain ultrasound (US) showed dilation of the lateral ventricles and the absence of the corpus callosum, these findings were not fully confirmed. Therefore, magnetic resonance imaging (MRI) of the brain was conducted to confirm the complex diagnosis, and the examination revealed complete ACC. Diagnosing ACC in a neonate demonstrates the complexity of diagnosis through the clinical presentation, especially at an early age. CONCLUSION: The clinical utility of neonatal US and MRI highlights the importance of an early diagnosis of ACC. MRI is more effective than the US in detecting this condition, and these imaging modalities provide the patient with an early diagnosis, which helps in treatment management.
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Magnetic resonance imaging (MRI) is essential for assessing shoulder conditions. This study aimed to evaluate current shoulder MRI practices in Jordan, including technical parameter patterns, and determine if they adhere to the American College of Radiology (ACR) guidelines. The retrospective analysis included data from 48 eligible participants from 13 MRI centers in March 2021. Descriptive and correlation data analysis were performed using IBM SPSS statistics version_20 and Excel 2013. Most MRI centers (50%) were private outpatient clinics with closed MRI machines above 1 Tesla. Most participants (62.5%) were male, and shoulder pain (47.9%) was the main clinical indication. Most shoulder orientations (68.7%, 33/48) were right shoulders, and the coronal MRI planes (43%, 121/280) were the most common. The alignment percentage for the axial plane was 100%, but MRI artifacts of the shoulder were present in 8.2% of cases (23/280). Dark fluid T1-W coronal sequence was not conducted in 25% of the cases. The percentage of the field view (FOV) within ACR recommendations was 45% (126/281), and slice thickness parameters were 96% (269/281). The recommended pixel area for all sequences was 47.9% (134/280), encompassing all axial, sagittal oblique, and coronal planes. However, crucial parameters, such as FOV and slice thickness, were inadequate and did not meet the ACR guidelines, resulting in suboptimal image quality of shoulder MRI. To improve MRI image quality, it is recommended that MRI technologists receive ongoing education and training on appropriate MRI image parameters.
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Radiologia , Ombro , Humanos , Masculino , Feminino , Ombro/diagnóstico por imagem , Estudos Retrospectivos , Jordânia , Imageamento por Ressonância Magnética/métodosRESUMO
BACKGROUND: Whole-body magnetic resonance imaging (WB-MRI) is a useful tool for revealing the disease-specific distribution of affected muscles and clinically asymptomatic muscle involvements in idiopathic inflammatory myopathies (IIMs). PURPOSE: To examine inflammatory changes in the systemic skeletal muscles, including the thoracoabdominal trunk, in IIMs using WB-MRI. MATERIAL AND METHODS: We prospectively obtained WB-MRI axial images from 10 patients with IIMs, including antisynthetase syndrome (ASS), immune-mediated necrotizing myopathy (IMNM), sporadic inclusion body myositis, and myopathy associated with antimitochondrial antibody. We evaluated 108 systemic skeletal muscles in short-tau inversion recovery (STIR) images and rated changes in signal intensity using a semiquantitative scale. Correlations between STIR sum score, peak creatine kinase (CK) and muscle strength were examined. We also investigated the correlation between STIR sum score within the thoracoabdominal trunk and forced vital capacity. RESULTS: High STIR signal changes were frequently identified in asymptomatic and routinely unexamined muscles. Thoracoabdominal trunk muscles were frequently involved in ASS and IMNM. Peak CK was positively correlated with the STIR sum score (R 2 = 0.62, p < .01). There was no significant correlation between the STIR sum score within the thoracoabdominal trunk and forced vital capacity. CONCLUSION: WB-MRI can detect subclinical muscle inflammation in the systemic muscles including the trunk muscles. STIR sum score is positively correlated with serum peak CK level; therefore, it could be a biomarker of overall muscle inflammation.