The Added Value of Bloodpool SPECT/CT in Painful Non-Operated Foot and Ankle Undiagnosed With Standard Three-Phase Bone Scintigraphy.

Purpose: To evaluate the interest of adding a bloodpool SPECT/CT to standard three-phase bone scintigraphy (BS) for etiological diagnosis of subacute and chronic lower extremity pains. Methods: We prospectively included patients addressed for pain of lower extremities lasting for at least 6 weeks, without previous surgery. They underwent a standard three-phase BS including late phase SPECT/CT, modified with an additional bloodpool SPECT/CT acquisition. Two independent physicians interpreted the images provided by both protocols. Diagnostic conclusion, diagnostic confidence, and interrater agreements were compared. Results: One hundred and eighteen lower extremities from 113 patients were analyzed (71 men, median age of 53 years). Adding bloodpool SPECT/CT to standard three-phase BS changed diagnostic conclusions in 24.6% (29/118) of lower extremities. The modified protocol revealed at least one diagnostic conclusion explaining the pain in 89% of extremities, rather than 83.1% with the standard protocol (p = 0.02). Tendinopathies were diagnosed in 12.7% of lower extremities, rather than 4.2% with standard BS (p = 0.002). Adding bloodpool SPECT/CT substantially increased overall confidence of each reader (p < 0.001). Inter-reader agreement was not significantly impacted. Conclusion: Adding bloodpool SPECT/CT to standard three-phase BS impacted diagnostic conclusion in a quarter of the patients with painful lower extremities, notably by revealing significantly more tendonitis.

Intense Increased 18F-FDG Uptake of Masticator Muscles After Cocaine Use.

F-FDG is the most widely used PET tracer worldwide. Before the examination, recommendations are given to patients to avoid muscular activities, with the goal to limit F-FDG uptake in muscles. Here, we report the case of a 36-year-old man with Hodgkin disease referred to our department to perform an F-FDG PET/CT for immunotherapy assessment. The PET images showed a homogeneous, symmetric, and very intense uptake of the masticatory muscles. The medical examination exhibited a trismus, and the patient revealed to have been using cocaine 15 minutes before injection of F-FDG.

Blood-Pool SPECT/CT in Chronic Ankle Tendinopathy.

We report 2 cases where blood-pool SPECT/CT had a high added value compared with standard 3-phase bone scintigraphy with only delayed SPECT/CT for the etiological diagnosis of painful ankles. Two men, aged 48 and 62 years, were referred for suspicions of medial and lateral malleoli stress fractures, respectively. Although standard planar blood-pool imaging and delayed SPECT/CT were inconclusive, blood-pool SPECT/CT showed markedly increased uptake along posterior tibial tendon and peroneal tendon, respectively, leading to diagnose tendonitises. These cases illustrate that blood-pool SPECT/CT can extend the diagnostic yield of bone scintigraphy to extraosseous origin, particularly in chronic lower extremities pain.

FDG PET in Diffuse Spinal Carcinomatous Meningitis.

A 65-year-old man, diagnosed with right paranasal sinus neuroendocrine carcinoma with skull base invasion and ipsilateral lymph node involvement underwent chemotherapy. Six months later, the patient underwent radiation therapy for right cervical lymph node recurrence. Two months after the end of the radiation therapy, the patient was referred to our department to perform a whole-body FDG PET for therapeutic assessment. It showed diffuse intense FDG uptake of the whole spinal canal. The physical examination revealed walking disorders. Meningeal contrast enhancement on MRI of the brain and the spinal cord was leading to the diagnosis of carcinomatous meningitis.