Clinical utility of technetium-99m-labelled leukocyte scan in diagnosis of vascular infections.

INTRODUCTION: The diagnosis of vascular graft infections and infected aneurysms via conventional methods such as computed tomography (CT) and ultrasound (US) can often be challenging. Nuclear medicine imaging techniques can detect infection in these difficult cases. We aim to evaluate the diagnostic value of technetium-99m-labelled leukocyte scans in diagnosing vascular graft infections in our centre. METHODS: There were 164 patient-scans identified over a 16-year period. The electronic clinical records, laboratory findings and radiology of these patients were reviewed. An adapted case definition of infection was defined using the criteria proposed by the Management of Aortic Graft Infection Collaboration. There were 43 patients identified to have vascular indications and had sufficient information to be divided into infected and non-infected groups. Imaging and reports of the leucocyte scans in these patients were analysed to calculate specificity and sensitivity. RESULTS: Overall sensitivity of leucocyte scans to detect vascular infection was 78.1% and specificity of 81.8% with a positive likelihood ratio of 4.30 and negative likelihood ratio of 0.27. Two false positives in patients with aortic grafts; one patient possibly had concurrent gastrointestinal infection and continued antibiotic treatment. The other patient had persistent uptake around an endoleak and was treated with lifelong antibiotics for aortic vascular graft infection on the basis of the leucocyte scan; no other clinical or laboratory evidence was found to fulfil the case definition of the vascular graft infection. CONCLUSION: Technetium-99m-labelled leukocyte scan can be a useful adjuvant test in diagnosing suspected vascular infections in this uncommon presentation.

Rib Cage Stabilisation With 3D-Printed Polyethylene Sternal Prosthesis Post-Sternotomy Mediastinitis.

BACKGROUND: Post-sternotomy mediastinitis (PSM) is a serious complication of median sternotomy. It is associated with a high mortality rate. Evidence based management recommends debridement followed by closure with vascularised flaps. When large areas of resections are performed, the use of sternal prosthesis could be considered to ensure chest wall stability and cosmesis. METHOD: We report an individualised three-dimensional (3D)-printed high-density polyethylene (HDPE) sternum implantation in a patient with a 10 cm chest wall defect. RESULTS: Chest wall reconstruction was uncomplicated and the patient tolerated the procedure well without cardiorespiratory compromise. Postoperatively, the wound healed well and the chest wall remained stable at outpatient clinic follow-up. CONCLUSION: Three-dimensional-printed HDPE prosthesis offers an alternative implant option for closing large chest wall defects for eroded sternum after cure of mediastinitis.

Desmoid fibromatosis of the chest wall.

We report a case of desmoid fibromatosis of the chest wall. A 70-year-old woman was referred to our hospital with right shoulder blade pain and paresthesia over the right upper breast. Chest X-ray and computed tomography demonstrated a 5 cm right apical mass in the chest. Biopsy of the mass demonstrated features of desmoid fibromatosis. The patient subsequently underwent surgical resection of the mass and received adjuvant radiation therapy for microscopic positive margins. In conclusion, although desmoid tumour of the chest is rare, it is worth considering in the differential diagnoses of chest wall tumours.