The reliability of measuring the density of the L1 vertebral body on CT imaging as a predictor of bone mineral density.

AIM: To determine whether the density of the L1 vertebra measured on computed tomography (CT) images correlates with the bone mineral density (BMD) as measured by quantitative computed tomography (QCT), and to determine the reliability of L1 density measurements by different observers to see if this measure could help identify patients who would benefit from formal BMD assessment. MATERIALS AND METHODS: Non-contrast CT along with a phantom for determination of BMD was performed on 30 healthy patients. The L1 density was measured by 3 observers at two time-points separated by at least 2 weeks. RESULTS: L1 density was well correlated to the QCT BMD (correlation coefficient 0.83; 95% confidence interval [CI]: 0.67-0.92). There was excellent intra- and interobserver agreement in L1 density measurements. There were excellent intra-class correlation coefficients for each observer's measurements at two separate time points with a coefficient for observer 1 of 0.94 (95% CI: 0.88-0.97) and for observer 2 and 3 of 0.99 (95% CI: 0.98-1). The interobserver measurements had an intra-class correlation coefficient of 0.98 (95% CI: 0.96-0.99). CONCLUSION: L1 vertebral density can be reliably measured on CT images and might be used as an indicator of BMD for opportunistic screening of patients with osteoporosis. Low bone density detected incidentally on CT imaging could be used to identify patients who should be further investigated and treated for osteoporosis.

Prospective study evaluating the relative sensitivity of 18F-NaF PET/CT for detecting skeletal metastases from renal cell carcinoma in comparison to multidetector CT and 99mTc-MDP bone scintigraphy, using an adaptive trial design.

BACKGROUND: The detection of occult bone metastases is a key factor in determining the management of patients with renal cell carcinoma (RCC), especially when curative surgery is considered. This prospective study assessed the sensitivity of (18)F-labelled sodium fluoride in conjunction with positron emission tomography/computed tomography ((18)F-NaF PET/CT) for detecting RCC bone metastases, compared with conventional imaging by bone scintigraphy or CT. PATIENTS AND METHODS: An adaptive two-stage trial design was utilized, which was stopped after the first stage due to statistical efficacy. Ten patients with stage IV RCC and bone metastases were imaged with (18)F-NaF PET/CT and (99m)Tc-labelled methylene diphosphonate ((99m)Tc-MDP) bone scintigraphy including pelvic single photon emission computed tomography (SPECT). Images were reported independently by experienced radiologists and nuclear medicine physicians using a 5-point scoring system. RESULTS: Seventy-seven lesions were diagnosed as malignant: 100% were identified by (18)F-NaF PET/CT, 46% by CT and 29% by bone scintigraphy/SPECT. Standard-of-care imaging with CT and bone scintigraphy identified 65% of the metastases reported by (18)F-NaF PET/CT. On an individual patient basis, (18)F-NaF PET/CT detected more RCC metastases than (99m)Tc-MDP bone scintigraphy/SPECT or CT alone (P = 0.007). The metabolic volumes, mean and maximum standardized uptake values (SUV mean and SUV max) of the malignant lesions were significantly greater than those of the benign lesions (P < 0.001). CONCLUSIONS: (18)F-NaF PET/CT is significantly more sensitive at detecting RCC skeletal metastases than conventional bone scintigraphy or CT. The detection of occult bone metastases could greatly alter patient management, particularly in the context when standard-of-care imaging is negative for skeletal metastases.

Radiological imaging of congenital hand anomalies--a 6-year single-centre experience and what the hand surgeons want to know.

OBJECTIVE: Congenital hand anomalies present a rare but important physical and emotional challenge for children and parents. Radiological imaging is important for accurate diagnosis, to aid decision making and to monitor changes in the growing hand. The goal of any treatment is to help the child achieve his/her maximum potential, to provide a useful hand with attention to cosmesis. We investigated the range of congenital hand anomalies imaged in a tertiary referral centre. We examined the timing of imaging and the key clinical questions. METHODS: The radiology imaging system was searched retrospectively for radiographs of congenital hand anomalies over a 6-year period. The images were reviewed and patient demographics, diagnosis and other imaging recorded. RESULTS: Over 6 years, 85 patients had imaging. Twenty-three patients had bilateral problems and 11 had recognised syndromes. The most common abnormalities imaged were duplicated thumbs (28 %), followed by syndactyly (18 %). Children were first imaged as early as 1 day old, with the median age of initial imaging 12 months. CONCLUSIONS: Thumb duplication and syndactyly are the most common conditions for which radiographs are requested at our hospital, although overall syndactyly is considered the most common congenital hand anomaly. For a variety of reasons, children are often imaged very early, before review by the Specialist in Children's Hand Surgery (despite surgery being unlikely before 1 year of age.) We discuss the classification systems and specific issues that hand surgeons want to know from the radiologists.