The value of combined assessment of vertebral fractures with 99mTc MDP scintigraphy and MRI in selecting and planning percutaneous vertebroplasty.

BACKGROUND: Percutaneous vertebroplasty is a minimally invasive radiological procedure intended for relieving painful vertebral fractures. Suitability depends largely on fracture age, with acute osteoporotic fractures being most appropriate. Selection and planning usually involves either Tc MDP scintigraphy or MRI. There is evidence indicating that either modality is predictive of response to vertebroplasty, but there is limited evidence promoting their combined use. AIM: The aim of the study was to establish the degree of concordance between MRI and Tc MDP scintigraphy in vertebral fracture assessment. MATERIALS AND METHODS: Our institution routinely uses both MRI and Tc MDP scintigraphy in vertebroplasty planning. This retrospective analysis included 39 patients, with a total of 73 vertebral fractures, all treated with vertebroplasty. The fractures were classified according to fracture age, aetiology and intermodality concordance. RESULTS: The overall concordance between MRI and Tc MDP scintigraphy was 63%. Almost twice as many fractures classified as 'acute/ subacute' on MRI were so classified on Tc MDP scintigraphy. CONCLUSION: Using MRI without Tc MDP scintigraphy, 48.2% of the potentially suitable vertebroplasty targets (37% of the total vertebral lesions) would likely have been overlooked. Clearly, Tc MDP scintigraphy and MRI provide different but complementary information on vertebral fractures, and these results support the use of dual-modality assessment in vertebroplasty selection and planning.

Percutaneous vertebroplasty to treat painful myelomatous vertebral deposits-long-term efficacy outcomes.

Developed for benign conditions including osteoporotic fractures and haemangiomas, vertebroplasty has since been employed in neoplastic lesions, including myeloma. Advances in myeloma treatments, yielding improved survival times, have led to an increasing need for effective therapies that improve quality of life. The first randomised trials of vertebroplasty to treat painful osteoporotic crush fractures have cast doubt of its benefit over a placebo procedure, with a proposed rationale that fracture healing over time may account for the non-superiority of the results. However, these findings cannot be extrapolated to myeloma where the pathology is one of progressive bony destruction coupled with failure of new bone formation. In this paper, we present the outcome data for myeloma patients treated at our tertiary referral centre over a 5-year period, focusing on both subjective and objective measures of efficacy and safety. Records were reviewed to extract pain score, function and analgesia pre/post-procedure. Where possible, patients were then contacted directly and asked to assess their benefit by grading change in pain score, analgesia use and mobility. Performance status was assessed using the Eastern Cooperative Oncology Group scale. Of the 26 patients treated for painful thoraco-lumbar lesions, 77% reported improved pain score (P < 0.003). Analgesia reduction, better mobility and improved performance status were also seen. Our data support the consideration of vertebroplasty as a first-line treatment for painful myelomatous vertebral disease. Prospective randomised studies are now required to further define its role.

The efficacy of percutaneous vertebroplasty for vertebral metastases associated with solid malignancies.

BACKGROUND: Percutaneous vertebroplasty appears beneficial for patients with acute compression fractures of multiple aetiologies including myeloma, osteoporosis and trauma. There are few reports on its use in the setting of metastatic solid malignancy. METHODS: We identified all individuals who had undergone percutaneous vertebroplasty at our institution since 2004 and focused on those with metastatic solid malignancies. Their clinical characteristics and outcomes were investigated. RESULTS: From 136 cases that underwent percutaneous vertebroplasties, 19 were performed mainly in breast, prostate, lung and renal cancers. Of these 19 cases, 10 patients (53%) were treated for solitary lesions, 3 (16%) were injected at two levels and the remaining 6 cases (31%) underwent cement injection at three levels. The majority of individuals (84%) reported short- and long-term symptomatic improvements. At a median follow-up of one year, six patients have died. CONCLUSIONS: Percutaneous vertebroplasty appears as an effective palliative procedure in patients with compression fractures secondary to metastatic solid malignancy. Its use can be successfully combined with other treatment modalities (radiotherapy and chemotherapy).

Ventilation-perfusion scintigraphy is more sensitive than multidetector CTPA in detecting chronic thromboembolic pulmonary disease as a treatable cause of pulmonary hypertension.

UNLABELLED: Pulmonary hypertension (PH) is a progressive disease with a poor prognosis. Identifying chronic thromboembolic pulmonary disease as a cause of PH has major clinical implications as these patients could be potentially offered a surgical cure. Ventilation-perfusion (V/Q) scintigraphy has a high sensitivity to detect embolic disease but its value has been challenged with the emergence of multidetector CT pulmonary angiography (CTPA). We compared the value of V/Q scintigraphy with CTPA in detecting chronic thromboembolic pulmonary disease. METHODS: We retrospectively reviewed the results of V/Q scintigraphy and CTPA performed on patients who had been referred to the Pulmonary Hypertension Service at Hammersmith Hospital between 2000 and 2005. A total of 227 patients (85 males, 142 females; age range, 18-81 y; mean age, 42 y) had all tests done at Hammersmith Hospital and were included in the study. Interpretation of scans was according to the modified PIOPED (Prospective Investigation of Pulmonary Embolism Diagnosis) criteria. CTPA was considered as suggestive of chronic thromboembolic pulmonary disease if it showed visualization of the thrombus or webs, recanalization, perfusion abnormalities, stenosis, or strictures. Standard pulmonary angiography was performed via femoral approach. In 90% of the cases, CTPA and V/Q scintigraphy were performed within 10 d. RESULTS: Seventy-eight patients (group A) had a final diagnosis of chronic thromboembolic pulmonary hypertension (CTEPH) and 149 (group B) had non-CTEPH etiology. Among group A, V/Q scintigraphy was reported as high probability in 75 patients, intermediate probability in 1 patient, and low probability in 2 patients. CTPA was positive in 40 patients and negative in 38 patients. Among group B, V/Q scintigraphy was reported as low probability in 134, intermediate probability in 7, and high probability in 8 patients. CTPA was negative in 148 patients and false-positive in 1 patient. Statistical analysis showed V/Q scintigraphy to have a sensitivity of 96%-97.4% and a specificity of 90%-95%. CTPA showed a sensitivity of 51% and a specificity of 99%. CONCLUSION: Our results demonstrate that V/Q scintigraphy has a higher sensitivity than CTPA in detecting CTEPH as a potential curable cause of PH.

68Ga-DOTATATE PET in neuroectodermal tumours: first experience.

BACKGROUND AND AIM: Phaeochromocytoma is initially imaged with computed tomography (CT) or magnetic resonance imaging (MRI) but functional imaging is commonly needed to assess disease activity, the presence of metastasis and response to therapy. Traditionally, this is done with 123I -MIBG with good sensitivity and specificity. However, spatial resolution remains limited even with SPECT. We aimed to assess the utility of a new somatostatin analogue PET tracer, 68Ga-DOTATATE in the management of phaeochromocytoma. METHODS: We retrospectively reviewed five patients with malignant phaeochromocytoma who underwent imaging with CT and 123I-MIBG and compared the results with those of PET imaging using 68Ga-DOTATATE. Blinded analysis of the numbers and extent of lesions were done for all imaging modality. RESULTS: Two patients had negative 123I-MIBG and positive 68Ga-DOTATATE scans. One had a weakly positive 123I-MIBG and a strongly positive 68Ga-DOTATATE scan. One had a positive 123I-MIBG and positive 68Ga-DOTATATE scans. The fifth patient was negative to all imaging including CT. 68Ga-DOTATATE showed more lesions with higher uptake and better resolution compared to 123I-MIBG. CONCLUSION: The findings in our small group of patients demonstrate the value of somatostatin receptor PET imaging in malignant phaeochromocytoma. In lesions with no or low MIBG uptake, the next investigation of choice should be PET imaging with 68Ga-DOTATATE, in view to therapy with Y-labelled DOTATATE.

Concordant F-18 FDG PET and Y-90 Bremsstrahlung scans depict selective delivery of Y-90-microspheres to liver tumors: confirmation with histopathology.

Selective Internal Radiation Therapy using yttrium-90 (Y-90) microspheres is a novel method for the treatment of advanced liver cancer. The procedure involves intrahepatic arterial delivery of the Y-90 microspheres. Since hepatic tumors derive their blood supply mainly from the hepatic arteries, it is assumed that the microspheres will be preferentially delivered to tumor cells. However, this has not been confirmed at histology. We report a case of hepatic metastasis from an unknown primary, where treatment with Y-90 microspheres was the only available option due to inoperability and low tolerance to chemotherapy. Pretherapy F-18 FDG-PET scan defined the distribution of the active tumor within the liver. Following the injection of Y-90 microspheres, Bremsstrahlung imaging showed uptake only in the F-18 FDG-PET-defined tumor area. Post therapy debulking surgery was performed and histopathology of tumor samples confirmed the preferential distribution of the injected microspheres in the hepatic tumor circulation with very little in the healthy liver tissue. The case confirms the preferential blood flow to hepatic tumors as depicted by the distribution of Y-90 microspheres injected directly in the hepatic arteries. It also demonstrates that concordance between F-18 FDG-PET and Y-90 Bremsstrahlung scans can be a useful clue to the in vivo distribution of microspheres.

Imaging appearance of thoracic amyloidosis.

Amyloidosis is a disease caused by the deposition of abnormal proteins within extracellular soft tissues, and affects the respiratory tract in 50% of cases. Pulmonary involvement may be secondary to systemic disease or due to the accumulation of locally produced amyloid, and this differentiation has important prognostic and therapeutic implications. This pictorial essay, using cases of biopsy-proven respiratory tract amyloidosis, aims to depict the spectrum of imaging findings, and those of CT in particular, that can be of use in distinguishing between the 2 typical patterns of the disease.

Comparison between arthroscopy and 3 dimensional double echo steady state 3D-DESS sequences in magnetic resonance imaging of internal derangements of the knee.

OBJECTIVE: This study was performed with the aim of evaluating the usefulness of 3 dimensional double-echo steady state sequences in examining the internal derangements of the knee. Arthroscopy was used as a referral standard. METHODS: The study was performed in the Radiology and Arthroscopy Departments of King's College Hospital, London, United Kingdom, during a 6-month period from January 1997 to June 1997. All patients who had knee magnetic resonance imaging within 3 months of arthroscopy were retrospectively studied. Thirty-three patients fulfilled these criteria and were selected. RESULTS: Three dimensional double-echo steady state sequences produced sensitivity for detecting meniscal tears of 87.5% for medial menisci (MM) and 75% for lateral menisci (LM). Specificity was 76% for MM and 96% for LM; positive predictive value (PPV) was 46.1% for MM and 85.7% for LM and negative predictive value (NPV) of 95% for MM and 96% for LM. The sensitivity for the anterior cruciate ligament was 83.3%, specificity was 77.7%, PPV was 45.4% and NPV was 95.4%. CONCLUSION: Three dimensional double-echo steady state sequences are useful in evaluating internal derangement of the knee, especially in advanced cartilage lesions.

Magic angle effects in MR neurography.

BACKGROUND AND PURPOSE: Magic angle effects are well recognized in MR imaging of tendons and ligaments, but have received virtually no attention in MR neurography. We investigated the hypothesis that signal intensity from peripheral nerves is increased when the nerve's orientation to the constant magnetic induction field (B(0)) approaches 55 degrees (the magic angle). METHODS: Ten volunteers were examined with their peripheral nerves at different orientations to B(0) to detect any changes in signal intensity and provide data to estimate T2. Two patients with rheumatoid arthritis also had their median nerves examined at 0 degrees and 55 degrees. RESULTS: When examined with a short TI inversion-recovery sequence with different TEs, the median nerve showed a 46-175% increase in signal intensity between 0 degrees and 55 degrees and an increase in mean T2 from 47.2 to 65.8 msec. When examined in 5 degrees to 10 degrees increments from 0 degrees to 90 degrees, the median nerve signal intensity changed in a manner consistent with the magic angle effect. No significant change was observed in skeletal muscle. Ulnar and sciatic nerves also showed changes in signal intensity depending on their orientation to B(0). Components of the brachial plexus were orientated at about 55 degrees to B(0) and showed a higher signal intensity than that of nerves in the upper arm that were nearly parallel to B(0). A reduction in the change in signal intensity in the median nerve with orientation was observed in the two patients with rheumatoid arthritis. CONCLUSION: Signal intensity of peripheral nerves changes with orientation to B(0). This is probably the result of the magic angle effect from the highly ordered, linearly orientated collagen within them. Differences in signal intensity with orientation may simulate disease and be a source of diagnostic confusion.

Variations in lower limb venous anatomy: implications for US diagnosis of deep vein thrombosis.

PURPOSE: To retrospectively review bilateral venograms free of thrombus to evaluate the frequency and types of variations seen in venous anatomy. MATERIALS AND METHODS: A retrospective review of 404 bilateral (808 limbs) lower limb venograms obtained from medical patients participating in a thromboprophylaxis clinical trial and found to be free of thrombus was performed. Venograms were evaluated according to predetermined criteria for the presence of duplication of vessels and inter- and intraindividual variations in venous anatomy. Variations were assessed with analysis of variance and chi2 tests. RESULTS: Two vessels were seen in the popliteal fossa on 337 (42%) of 808 venograms, and 41 (5%) were true duplicated popliteal veins. There were 253 (31%) duplicated superficial femoral veins (SFVs), with 12 (1.5%) being complex duplicated systems. Of 265 duplicated SFVs, 138 (52%) began in the midthigh region and 80 (30%), in the adductor canal region. The duplicated vessel was medial to the main SFV in 122 (46%), lateral in 131 (49%), and both (ie, triplications) in 12 (4.5%). The length of the duplicated SFV ranged from 1 to 35 cm; 6-15 cm was the most common length in 162 (62%) SFVs. There was no significant association between the incidence of anatomic variations and age or sex (P >.1). The presence of multiple vessels in one leg was strongly correlated with the probability of occurrence in the other leg (P <.001). CONCLUSION: Variations in lower limb venous anatomy are common and have important implications for the US diagnosis of deep vein thrombosis.