Automatic Assessment Of Hip Effusion From MRI.

Joint effusion is a hallmark of osteoarthritis (OA) associated with stiffness, and may relate to pain, disability, and long-term outcomes. However, it is difficult to quantify accurately. We propose a new Deep Learning (DL) approach for automatic effusion assessment from Magnetic Resonance Imaging (MRI) using volumetric quantification measures (VQM). We developed a new multiplane ensemble convolutional neural network (CNN) approach for 1) localizing bony anatomy and 2) detecting effusion regions. CNNs were trained on femoral head and effusion regions manually segmented from 3856 images (63 patients). Upon validation on a non-overlapping set of 2040 images (34 patients) DL showed high agreement with ground-truth in terms of Dice score (0.85), sensitivity (0.86) and precision (0.83). Agreement of VQM per-patient was high for DL vs experts in term of Intraclass correlation coefficient (ICC)= 0.88[0.80,0.93]. We expect this technique to reduce inter-observer variability in effusion assessment, reducing expert time and potentially improving the quality of OA care.Clinical Relevance- Our technique for automatic assessment of hip MRI can be used for volumetric measurement of effusion. We expect this to reduce variability in OA biomarker assessment and provide more reliable indicators for disease progression.

Development of a technique for MRI gold-standard direct volumetric measurement of complex joint effusion, and validation at the hip.

OBJECTIVE: Accurate joint fluid quantification on MRI cannot simply rely on measuring the maximum fluid depth or using an ellipsoid approximation as this does not fully characterize the complex shape of a fluid-filled joint. As per the Outcome Measurement in Rheumatology (OMERACT) filter, we sought to evaluate the feasibility, reliability, and validity of a semi-automated supervised technique to quantify hip effusion volume. MATERIALS AND METHODS: Ninety-three hip osteoarthritis patients were imaged with coronal short TI inversion recovery (STIR) and sagittal intermediate weighted fat-suppressed (IWFS) sequences at two time points (Fig. 1). Volumetric quantitative measurement (VQM) of joint fluid and measurement of the largest femoral neck fluid thickness (FTM) was performed using the custom MATLAB software. Self-reported Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and clinical measures of pain, stiffness, and function were recorded. RESULTS: Inter-observer reliability was significantly higher for VQM than FTM (ICC = 0.96 vs. 0.85, p < 0.05). VQM and FTM correlated moderately (r = 0.76, p < 0.0001). There was significantly more articular fluid in symptomatic than asymptomatic hips at baseline (mean = 9.8 vs. 5.9 mL). Volumetric quantitative measurement generally displayed more frequent and stronger correlations to clinical parameters than FTM. Volumetric quantitative measurement required 3.9 min/hip vs. < 1 min/hip for femoral neck fluid thickness. CONCLUSION: Volumetric quantitative measurement of joint effusion can serve as an MRI gold-standard, could apply to other joints and collections, and is highly suited to future automation.

Normal hip joint fluid volumes in healthy children of different ages, based on MRI volumetric quantitative measurement.

BACKGROUND: While magnetic resonance imaging (MRI) of the pelvis and hips is common in pediatric patients, to date there are no data on the quantification of normal hip joint fluid volume in this patient population. OBJECTIVE: We sought to assess the feasibility and reliability of quantitative hip joint fluid measurement in the pediatric population to estimate the normal volume of fluid in a pediatric hip joint. MATERIALS AND METHODS: Seventy healthy children ages 8-17 years underwent a pelvic MRI including a large field of view coronal T2 fat-saturated sequence where hips were entirely imaged. Following 3 training sessions, 2 readers with experience in musculoskeletal imaging performed volumetric quantitative measurements of hip fluid (140 hips) using semiautomated pixel-based thresholding on custom MATLAB software. RESULTS: The mean processing time per hip was 2 min, 41 s. The mean volume of fluid in a hip joint was 2.1 mL (range: 0.38-5.41 mL), increasing slightly with age. Volumes were also greater in boys than in girls (P=0.004). Intra-observer and interobserver agreement were high (intra-class correlation coefficients 0.93 and 0.98, respectively), with mean volume differences of 0.04 mL for intra-observer and 0.09 mL for interobserver. CONCLUSION: A semiautomated pixel-based thresholding approach was feasible and reliable for measuring joint fluid in pediatric hip MRI. The average fluid volume of 2.1 mL can represent a visually substantial quantity of fluid per MRI slice, particularly in small children, and should not be misinterpreted as a joint effusion.

Vacuum-assisted complete excision of solid intraductal/intracystic masses and complex cysts: Is follow-up necessary?

INTRODUCTION: Management of complex cysts and benign intraductal/intracystic masses is controversial. The aim of this study was to determine if the complete removal of the complex cyst lesions with ultrasound-guided vacuum-assisted excision (US-VAE) is sufficient for their safe management when the histological diagnosis obtained at biopsy is benign. SUBJECTS AND METHODS: This is a single institution retrospective study performed on patients who underwent breast biopsy between April 2007 and September 2013. Patients with complete removal of complex cyst lesion of a BIRADS 4 lesion by US-VAE that obtained a benign diagnosis were included. Size, morphology, histological diagnosis, and surgical or imaging follow-up of the lesions were analyzed. RESULTS: During the study period, 131 lesions met the inclusion criteria. Benign papilloma represented 32% (42/131) of the lesions; the remaining lesions had various benign diagnoses. Mean size of the solid mass or the cysts' thickest septum was 7 mm (range, 2-24). Mean imaging follow-up was 34.9 months (24-99 months) in 115 lesions. No recurrence or malignancy in the post-biopsy bed were observed during follow-up. Eleven lesions (8.4%) underwent surgery as follow-up: no cancer was found, but two lesions demonstrated atypia. CONCLUSIONS: Complex cyst lesion image completely excised with US-VAE and with a benign histology at biopsy might not require further imaging follow-up or surgery and a return to routine screening can be safely recommended. In a world where healthcare delivery and accessibility is important, elimination of unnecessary follow-ups is pertinent given its lower cost and lesser social impact.