Beyond the clot: perfusion imaging of the pulmonary vasculature after COVID-19.

A compelling body of evidence points to pulmonary thrombosis and thromboembolism as a key feature of COVID-19. As the pandemic spread across the globe over the past few months, a timely call to arms was issued by a team of clinicians to consider the prospect of long-lasting pulmonary fibrotic damage and plan for structured follow-up. However, the component of post-thrombotic sequelae has been less widely considered. Although the long-term outcomes of COVID-19 are not known, should pulmonary vascular sequelae prove to be clinically significant, these have the potential to become a public health problem. In this Personal View, we propose a proactive follow-up strategy to evaluate residual clot burden, small vessel injury, and potential haemodynamic sequelae. A nuanced and physiological approach to follow-up imaging that looks beyond the clot, at the state of perfusion of lung tissue, is proposed as a key triage tool, with the potential to inform therapeutic strategies.

Fast Bowler's knee - anteromedial articular impingement.

PURPOSE: To describe a series of impingement lesions found on the anterior aspect of the medial femoral condyle in international cricketers. METHODS: Seven international level fast bowlers presented to our clinic with knee pain in the lead leg between 2005 and 2013. The mean age of the patients was 26.7 years (20-29 years). In all patients a careful history and examination was undertaken followed by appropriate investigations. Conservative management and arthroscopic surgery were performed on these cases. We aimed for a pain free quiet knee with resolved oedema on MRI and return to sport. RESULTS: MRI images showed oedema in the medial femoral condyle in all patients and 4 patients also had associated cartilage loss. These 4 patients underwent arthroscopic surgery whereas the other 3 were less symptomatic and were managed conservatively. All patients returned to international cricket at an average of 6 months in the non-operative group and 8 months in the operative group. CONCLUSION: Anterior impingement of the anteromedial femoral condyle can be a potentially serious lesion in the fast bowler. A strong index of suspicion regarding this lesion has to be exercised when a fast bowler attends with knee pain and effusion.

Pars interarticularis injury in elite athletes - The role of imaging in diagnosis and management.

Injuries of the lumbar neural arch, in particular the pars interarticularis, are widely considered to be due to abnormal bone stress secondary to repetitive loading/shearing, and are a common pathology and a main cause of lower back pain in elite athletes across a range of sports. Medical imaging plays a pivotal role in the diagnosis, monitoring and prognostication of neural arch injury. Early detection is highly desirable in the young elite athlete, as early injuries have been shown to require shorter recovery time and have a higher potential of full healing, whilst accurate grading of injury allows appropriate rehabilitation planning. Various imaging modalities are used in the diagnosis and management of pars stress injury, each with their strengths and weaknesses. There is currently a lack of general consensus over the most appropriate imaging pathway for neural arch injury in this specific group of patients. In this review article, we present an overview of neural arch injury, the various imaging modalities used and their imaging appearances with a brief pictorial review, and a proposed imaging algorithm with special considerations in the young elite athletes.

Hybrid Bone SPECT/CT Imaging in Evaluation of Chronic Low Back Pain: Correlation with Facet Joint Arthropathy.

BACKGROUND: Evidence to support the use of bone hydroxydiphosphonate (HDP) single photon emission computed tomography (SPECT/CT) in patients with facetogenic low back pain (LBP) is still limited. In this study we compared the scintigraphic patterns on bone SPECT/CT with the degree of structural facet joint (FJ) degeneration on CT in patients with LBP. METHODS: Ninety-nine consecutive patients with LBP were prospectively evaluated. Patients with known or suspected malignancy, trauma, infectious processes, chronic inflammatory diseases, and previous surgery were excluded. The effect of LBP on the daily quality of life was assessed with the Oswestry disability index (ODI). The Pathria grading system was used to score FJ degeneration on CT scans. The correlation between the degree of FJ degeneration and osteoblastic activity on SPECT/CT was analyzed with Kappa statistics. RESULTS: Ninety-nine patients were included (59 female, mean age 56.2 years). The mean ODI score was 38.5% (range, 8% to 72%). In all, 792 FJ (L2-3 to L5-S1) were examined. Of the FJs, 49.6% were Pathria grade 0-1 (normal to mild degeneration) on CT, 35% were grade 2 (moderate degeneration), and 16% were grade 3 (severe degeneration). Sixty-seven percent of the patients had scintigraphically active FJs on SPECT/CT. Sixty-nine percent of Pathria grade 3 FJs were scintigraphically active; 5.5% and 16.8% of Pathria grade 0-1 and Pathria grade 2, respectively, were active. Of the metabolically active FJs, 71.4% were at the L4-5/L5-S1 levels. CONCLUSIONS: The ability of SPECT/CT to precisely localize scintigraphically active FJs may provide significant improvement in the diagnosis and treatment of patients with LBP. In this study we demonstrate that in >40% of FJs, the scintigraphic patterns on SPECT/CT did not correlate with the degree of degeneration on CT.

Hybrid Bone Single Photon Emission Computed Tomography Imaging in Evaluation of Chronic Low Back Pain: Correlation with Modic Changes and Degenerative Disc Disease.

BACKGROUND AND OBJECTIVE: Multiple radiologic modalities are used in the evaluation of patients with low back pain (LBP). Only limited evidence currently exists to support the use of bone hydroxydiphosphonate single photon emission computed tomography (SPECT/CT) in patients with Modic changes (MCs) and degenerative disc disease. The aim of this study was to assess the value of the hybrid bone SPECT/CT imaging in patients with chronic LBP. We evaluate the correlation of hybrid bone SPECT/CT imaging patterns with MCs and disc abnormalities on magnetic resonance imaging (MRI). METHODS: This was a prospective study. Ninety-nine consecutive patients with LBP from a single center. The degree of lumbar intervertebral disc and endplate degeneration on MRI and osteoblastic activity was shown on SPECT/CT. These 99 consecutive patients with LBP were prospectively evaluated. Patients with contemporary lumbosacral spine MRI and bone SPECT/CT were included. Patients with known or suspected malignancy, trauma, infectious processes, and previous surgery were excluded. The effect of LBP on the daily quality of life was assessed using Oswestry disability index. We analyzed the correlation between the degenerative changes at the intervertebral disc spaces and endplates on MRI and bone SPECT/CT findings using receiver operating characteristic curve analysis and Kappa statistics. The Pfirrmann grading system was used to score the severity of disc space degeneration on MRI scans. RESULTS: A total of 99 patients were included in the study (58 women, 41 men; mean age, 56.2 years). Mean Oswestry disability index score was 38.5% (range, 8%-72%). The L2-3 through to L5-S1 levels were studied. MCs were found in 54% of patients. Of the 396 levels examined 85 were found to have MCs (21.5%). The most affected levels were L4-5 (31.3%) and L5-S1 (40.9%). Pfirrmann grade 5 disc space (72.9%) was associated with MC (Pp<0.001). MC (70.6%) and Pfirrmann grade 5 disc spaces (73%) resulted in scintigraphically active endplate/disc space on SPECT/CT (P< 0.001). Bone SPECT/CT showed high metabolic activity in 96.1% of endplates with MC type I, 56% with MC type II, and 77.8% with MC type III. CONCLUSIONS: In this study we found a high agreement between MCs and increased metabolic activity on bone SPECT/CT imaging. MC type 1 and Pfirrmann grade 5 were the best binary predictors for positivity on bone SPECT/CT and had equivalent correlations. Lower vertebral levels in the lumbar spine were associated with higher degree of disc degeneration, high frequency of MCs, and positivity on bone SPECT/CT.

Joint arthropathy at the cranio-vertebral junction. Scintigraphic patterns on bone SPECT/CT.

Osteoarthritic degeneration at the cranio-vertebral junction (CVJ) is an underrecognized source of suboccipital and neck pain, limited range of motion and cervicogenic headaches. Correlation of radiographic findings with clinical symptoms is often difficult. Limited evidence currently exists to support the use of bone single-photon emission computed tomography/computed tomography (SPECT/CT) in this subgroup of patients. The aim of this study was to describe the scintigraphic patterns of joint arthropathy at the CVJ on bone SPECT/CT in patients with suboccipital/neck pain and cervicogenic headache. Patients with more than 3 months of suboccipital/neck pain/cervicogenic headache and abnormal SPECT/CT findings at the CVJ were included. Patients with known/suspected malignancy, trauma, infectious processes and previous surgery at the CVJ were excluded. Neck disability index (NDI), visual analogue scale (VAS) and treatment were recorded for each patient. Patterns of osteoblastic activity at the CVJ on bone SPECT/CT were described and correlated with arthritic changes on conventional scans. Eighteen patients were included (10 females, mean age 68). Mean NDI score was 22. Mean VAS was 7.5. On bone SPECT/CT, it was found that 13 patients had high osteoblastic activity unilaterally at the atlanto-axial joint (AAJ); two patients at the atlanto-dental joint (ADJ), one at the occipito-atlantal joint (OAJ), one at both OAJ and ADJ and one at the level of C2 pars/pedicle unilaterally. Metabolic activity on SPECT/CT was associated with severe degenerative changes on CT scans. The ability of hybrid bone SPECT/CT to precisely localize osteoblastic activity at the CVJ may provide significant improvement in the diagnosis and treatment of patients with suboccipital/neck pain and joint arthropathy at the CVJ. Further clinical studies are needed to establish the real clinical impact of bone SPECT/CT in the treatment of patients with suboccipital neck pain.

Role of SPECT/CT in differentiated thyroid cancer.

Radioiodine scintigraphy and therapy has played a major role in the treatment and follow-up of thyroid cancer patients for decades. Single-photon emission computed tomography/computed tomography in this setting is emerging as a useful tool in accurately localizing sites of pathological uptake and physiological mimics of disease, thus providing more accurate staging prognostic information for risk stratification, which in turn tailors management and follow-up regimes. This review presents the current evidence and potential indications of single-photon emission computed tomography/computed tomography in thyroid cancer.