OMERACT Hip Inflammation Magnetic Resonance Imaging Scoring System (HIMRISS) Assessment in Longitudinal Study.

OBJECTIVE: To assess reliability, feasibility, and responsiveness of Hip Inflammation Magnetic resonance imaging Scoring System (HIMRISS) for bone marrow lesions (BML) in hip osteoarthritis (OA). METHODS: HIMRISS was scored by 8 readers in 360 hips of 90 patients imaged pre/post-hip steroid injection. Pre-scoring, new readers trained online to achieve intraclass correlation coefficient (ICC) > 0.80 versus experts. RESULTS: HIMRISS reliability was excellent for BML status (ICC 0.83-0.92). Despite small changes post-injection, reliability of BML change scores was high in femur (0.76-0.81) and moderate in acetabulum (0.42-0.56). CONCLUSION: HIMRISS should be a priority for further assessment of hip BML in OA, and evaluated for use in other arthropathies.

Dual-energy contrast-enhanced CT to evaluate scaphoid osteonecrosis with surgical correlation.

To evaluate the validity of contrast enhanced dual energy CT using a lung perfusion algorithm in assessing for post-traumatic scaphoid proximal pole avascular necrosis. From Aug 2013 to Aug 2016, 18 patients (19 wrists, 16 males, 2 females, mean age 28 years) were assessed as high-risk for proximal pole scaphoid avascular necrosis by a single surgeon following a scaphoid fracture and were referred for contrast-enhanced dual energy CT. 8 wrists had specimens sent for correlative histological analysis and 11 were correlated with operative notes. Eight surgical specimens were sent to histology and showed a 100% correlation (8/8) with the DECT findings. The remaining 11 wrists that did not have a specimen sent had in-surgery findings that also correlated with DECT. A single case was discrepant (1/11) due to presence of an intra-osseous ganglion, which was reported as osteonecrosis on CT, but considered viable at surgery. No case was called viable on CT that proved to be necrotic at either surgery or histologically. Contrast-enhanced dual energy CT using a perfusion algorithm is an innovative and promising method in evaluating viability of the post-trauma proximal pole of scaphoid.

Tail of Superficial Myxofibrosarcoma and Undifferentiated Pleomorphic Sarcoma After Preoperative Radiotherapy.

BACKGROUND/AIM: Superficial myxofibrosarcoma (MFS) and undifferentiated pleomorphic sarcoma (UPS) are highly associated with infiltrative growth (tail sign) and local recurrence, but the impact of preoperative radiotherapy is uncertain. PATIENTS AND METHODS: Eight consecutive superficial MFS and 10 superficial UPS cases treated with preoperative radiotherapy and surgery were reviewed. Pathological response, surgical margin and magnetic resonance imaging (MRI) were retrospectively evaluated. Oncological events were reported in a descriptive form. RESULTS: Pathologically, nearly-complete response was observed in six UPS cases. Tail sign was pathologically detected in 13 cases, eight of which remained viable. Among the eight cases with viable tail, three cases, including two with positive margin, locally recurred. No major discrepancy was observed between tail length on pre-treatment T1-weighted post-contrast, fat-saturated MRI and pathological tail length. CONCLUSION: Tail of superficial MFS and UPS can retain viability even after radiotherapy and cause local recurrence unless they respond to radiotherapy well. Wider resection including the tail on MRI is recommended.

Gouty arthropathy: Review of clinico-pathologic and imaging features.

Gout is a common inflammatory arthropathy in adults, with the prevalence increasing in males of older age. It occurs when monosodium urate (MSU) crystals are deposited in joints and connective tissue causing inflammation. The gold standard for the diagnosis of gout is the demonstration of negatively birefringent, needle-shaped MSU crystals through synovial fluid aspiration. However, this is an invasive technique and may not always be conclusive or feasible. Imaging techniques have been developed to aid in diagnosis of gout non-invasively. Radiography has a low utility in the early diagnosis of gout and demonstrates erosions in late stages. Ultrasound (US) has a high overall sensitivity in diagnosing gout with the 'double contour' sign having a high specificity. Magnetic resonance imaging is good at detecting tophi, bone marrow oedema and erosions, but has a limited role in diagnosis because of its high cost and limited availability. Conventional computed tomography (CT) has no role in the routine diagnosis of gout before development of erosions and tophi. A newer technology, dual-energy CT (DECT) has been shown to be able to detect MSU crystals burden with high accuracy. It has a higher specificity and lower sensitivity that US in gout diagnosis. However, because of radiation exposure and cost, it has a better utility in diagnosing clinically suspected gout complicated by other concurrent rheumatologic conditions or if radiography, US and synovial aspiration are inconclusive or not feasible. This paper will review the clinico-pathologic and imaging features of gouty arthropathy.

Biopsy and the diagnostic evaluation of musculoskeletal tumours: critical but often missed in the 21st century.

Bone and soft-tissue sarcomas are rare and heterogeneous malignancies arising from tissues of mesenchymal origin. Treatment planning is informed by accurate diagnosis for which biopsy is the diagnostic standard. Biopsy in the setting of suspected malignancy is a technically challenging procedure that should only be performed at specialist institutions. Without the requisite expertise, they can compromise the viability of reconstructive procedures and may make necessary amputation to achieve adequate surgical margins. The risk of complications arising from the procedure must be minimized and therefore biopsy should always be preceded by imaging. There must be no attempt at biopsy or excision prior to referral if there is any suspicion of malignancy. Patients with suspected bone and soft-tissue tumours are best evaluated and treated at specialist sarcoma centres under the care of expert multidisciplinary teams. Prompt referral to a specialist sarcoma centre should always be made prior to biopsy for any suspicious mass that is painful, progressively increasing in size, greater than 5 cm in diameter, deep to deep fascia or recurs following inadvertent excision.

MRI and thallium features of pigmented villonodular synovitis and giant cell tumours of tendon sheaths: a retrospective single centre study of imaging and literature review.

OBJECTIVE: The purpose of this study was to characterize the MRI and thallium-201 ((201)TI) scintigraphy attributes of pigmented villonodular synovitis (PVNS) and giant cell tumours of tendon sheaths (GCTTS). The epidemiology of these uncommon lesions was also assessed and less commonly encountered pathology reported on including multifocality, necrosis and concurrent malignancy. METHODS: A retrospective single centre review of MRI and (201)TI scintigraphy findings for 83 surgically proven or biopsy-proven consecutive cases of PVNS was undertaken. Radiological findings including lesion size, (201)TI uptake (as a marker of metabolic activity), location, extent and patient demographics were correlated with biopsy and surgical specimen histology. Typical appearances are described, as well as less common imaging manifestations. The study period encompassed all patients presenting or referred to a tertiary bone and soft-tissue tumour referral centre with PVNS or GCTTS between 1 January 2007 and the 1 December 2013. RESULTS: Lesions occur most commonly around the knee joint in the fourth decade of life, with younger patients showing a tendency to occur in the hip. Features of PVNS and GTTS include bone erosion, ligamentous and cartilage replacement, muscle infiltration and multifocality. MR signal characteristics were variable but post-contrast enhancement was near-universal. 14 of 83 cases showed no uptake of (201)TI and revealed a statistically significant smaller average axial dimension of 19.8 mm than lesions displaying active (201)TI uptake of 36.4 mm, p = 0.016. Four lesions demonstrated central necrosis on gross histology, two of each from both the (201)TI-avid and (201)TI-non-avid groups. CONCLUSION: MR is the imaging modality of choice when considering the diagnosis of these uncommon tumours. (201)TI scintigraphy as a marker of metabolic activity further adds minimal value although small lesions can appear to lack (201)TI avidity. ADVANCES IN KNOWLEDGE: This article depicts typical imaging findings of PVNS/GCTTS and also a subset of lesions that demonstrate no uptake on metabolic functional imaging, namely smaller sized lesions irrespective of anatomical location. This represents an important departure from previously documented imaging manifestations, whereby an absence of isotope accumulation suggested exclusion of these lesions from the differential diagnosis. These findings have important implications when considering the diagnosis of these uncommon lesions and may be important when interpreting post-treatment response. We suggest that further investigation, for example, with MRI is valuable in order to clarify potential post-treatment response, as well as the use of alternate functional imaging modalities such as positron emission tomography (PET), to further corroborate these findings.

Musculoskeletal desmoid tumours: Pre- and post-treatment radiological appearances.

This study was aimed to illustrate the pre- and post-treatment imaging findings of musculoskeletal desmoid tumours and describe current treatment methods. Imaging of histologically proven cases of desmoid tumours at St. Vincent's Hospital, Melbourne, were obtained via picture archiving communication system (PACS) and then assessed by two musculoskeletal radiologists. Suitable imaging both pre- and post-treatment were then obtained from PACS. All imaging chosen were de-identified. Ninety-two patients were found to have histologically proven cases of desmoid tumours between January 2000 and December 2013. Six patients with extra-abdominal tumours were selected, where pre- and post-treatment imaging was available. Desmoid tumours can occur in many areas of the body. Treatment of desmoids are varied. Although wide-margin surgery has been the traditional form of treatment, it still cannot guarantee absence of tumour recurrence despite microscopically tumour-free margins. Other forms of treatment such as non-steroidal anti-inflammatory drugs, radiotherapy, chemotherapy, tyrosine kinase inhibitors and also the conservative 'watch and wait' approach have been suggested, which show varying results.

Accuracy and complications of CT-guided core needle biopsy of peripheral nerve sheath tumours.

OBJECTIVE: This single-centre study retrospectively reviews the complications in patients that have occurred following peripheral nerve sheath tumour biopsy, and assesses whether there is an association with biopsy technique or underlying lesion characteristics. MATERIALS AND METHODS: 41 consecutive core needle biopsies of proven peripheral nerve sheath tumours over a 2-year period in a tertiary teaching hospital were reviewed. Patient demographics and symptoms, tumour characteristics and radiological appearances were recorded. Biopsy and surgical histology were correlated, and post-biopsy and surgical complications analyzed. RESULTS: 41 biopsies were performed in 38 patients. 68% schwannomas, 24% neurofibromas and 7% malignant peripheral nerve sheath tumours. Biopsy histology correlated with surgery in all cases. 71% of lesions were surgically excised. 60% of patients reported pain related to their lesion. Following the biopsy, 12% reported increased pain, which resolved in all cases. Pain exacerbation was noted in tumours smaller in size, more superficial and in closer proximity of the biopsy needle tip to the traversing nerve. Number of biopsy needle passes was not associated with an increased incidence of procedure-related pain. CONCLUSION: Core biopsy of a suspected peripheral nerve sheath tumour may be performed safely before excisional surgery to confirm lesion histology and assist prognosis. There is excellent correlation between core biopsy and excised surgical specimen histology. The most common complication of pain exacerbation is seen in a minority and is temporary, and more likely with smaller, more superficial lesions and a closer needle-tip to traversing nerve distance during biopsy.

Aggressive aneurysmal bone cyst in association with polyostotic fibrous dysplasia: A case report.

INTRODUCTION: Aneurysmal bone cyst occurring in the setting of previously diagnosed fibrous dysplasia is rare. While both are benign processes, pain, compression of nearby structures and risk of fracture can require treatment. PRESENTATION OF CASE: In this report, we describe a 56 year old male who developed an aggressive aneurysmal bone cyst secondary to fibrous dysplasia in the proximal tibia over a period of 8 months. He required an above knee amputation for disease and symptom control due to the aggressive nature of disease and medical comorbidities. DISCUSSION: The diagnosis of a secondary lesion can prove difficult. It is important to exclude a malignant disease process, particularly when imaging demonstrates an aggressive appearance. In this case, repeat imaging, CT guided biopsies and an open biopsy were performed to exclude malignancy prior to definitive surgical management. CONCLUSION: In order to exclude secondary lesions, we suggest further investigation for new onset pain in the setting of a benign lesion.

Musculoskeletal desmoid tumours: Diagnostic imaging appearances.

This study aimed to discuss the role medical imaging has on diagnosis of musculoskeletal desmoid tumours and to describe their radiological appearances on various imaging modalities. Imaging of histologically proven cases of desmoid tumours at St. Vincent's Hospital Melbourne were obtained via picture archiving communication system (PACS) and then assessed by two musculoskeletal radiologists. Suitable imagings were obtained from PACS. All imaging chosen was de-identified. Desmoid tumours can occur in many areas of the body. Imaging plays an important role in the diagnosis of these tumours and magnetic resonance imaging has been the gold standard for imaging and is the most accurate in terms of assessing tumour margins and involvement of surrounding structures.

Methodologies for semiquantitative evaluation of hip osteoarthritis by magnetic resonance imaging: approaches based on the whole organ and focused on active lesions.

OBJECTIVE: As a wider variety of therapeutic options for osteoarthritis (OA) becomes available, there is an increasing need to objectively evaluate disease severity on magnetic resonance imaging (MRI). This is more technically challenging at the hip than at the knee, and as a result, few systematic scoring systems exist. The OMERACT (Outcome Measures in Rheumatology) filter of truth, discrimination, and feasibility can be used to validate image-based scoring systems. Our objective was (1) to review the imaging features relevant to the assessment of severity and progression of hip OA; and (2) to review currently used methods to grade these features in existing hip OA scoring systems. METHODS: A systematic literature review was conducted. MEDLINE keyword search was performed for features of arthropathy (such as hip + bone marrow edema or lesion, synovitis, cyst, effusion, cartilage, etc.) and scoring system (hip + OA + MRI + score or grade), with a secondary manual search for additional references in the retrieved publications. RESULTS: Findings relevant to the severity of hip OA include imaging markers associated with inflammation (bone marrow lesion, synovitis, effusion), structural damage (cartilage loss, osteophytes, subchondral cysts, labral tears), and predisposing geometric factors (hip dysplasia, femoral-acetabular impingement). Two approaches to the semiquantitative assessment of hip OA are represented by Hip OA MRI Scoring System (HOAMS), a comprehensive whole organ assessment of nearly all findings, and the Hip Inflammation MRI Scoring System (HIMRISS), which selectively scores only active lesions (bone marrow lesion, synovitis/effusion). Validation is presently confined to limited assessment of reliability. CONCLUSION: Two methods for semiquantitative assessment of hip OA on MRI have been described and validation according to the OMERACT Filter is limited to evaluation of reliability.

Closure of bronchopleural fistula with Angio-Seal.

Bronchopleural fistula is rare and occurs most often after trauma or surgery. Conservative management and support comprise the initial treatment, but if unsuccessful, surgical closure is usually required. We describe for what is to our knowledge the first successful use of an Angio-Seal vascular closure device in a patient who was not a candidate for surgery.

The 'sentinel clot' sign in spontaneous retropharyngeal hematoma secondary to parathyroid apoplexy.

Spontaneous retropharyngeal hemorrhage from a cervical parathyroid adenoma is a rare complication of primary hyperparathyroidism. Because of its rarity, it has seldom been documented in the radiologic or ENT literature. Patients may present with a variety of manifestations, ranging from dysphagia to dysphonia to life-threatening dyspnea or hemorrhage. Awareness of a possible thyroid or parathyroid etiology may expedite treatment and prevent unnecessary interventions. We present a case of spontaneous retropharyngeal hemorrhage in which the "sentinel clot" sign enabled us to identify the lesion of origin.