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Introduction Bone marrow (BM) assessment is an important aspect of paediatric MRI, with the marrow cavity visible on almost every clinical MR examination. In practice, however, assessment for marrow infiltration in paediatric patients can be challenging. Our aim was to review the MRI appearance of normal BM from 0 to 5 years. Methods Consecutive body MR examinations over 7 years were retrospectively reviewed in patients aged 0–5 years. Patients with anticipated BM abnormality were excluded. All patients had imaging of the spine and/or pelvis with T1-weighted (T1) ± T2 with fat saturation, post-contrast T1-weighted, diffusion-weighted or out-of-phase sequences. Results Nineteen patients were included: nine (47%) infants, 11 (58%) boys, mean age 18.2 months (range 1 day to 3 years and 10 months). On T1 imaging, 69% infant marrow sites and 24% in children >1 year were isointense, the remainder were hyperintense. One hundred per cent BM was T2 fat saturation hyperintense. Enhancement following contrast was seen in 16% of BM sites. Restricted diffusion was seen in 100% infant BM and 50% BM in children >1 year. On out-of-phase imaging, no signal loss was seen in infants, and 21% BM in children >1 year showed signal loss. Conclusion Due to normal age-related differences in BM histology, MRI for marrow assessment in infants and young children can be misleading and may mimic marrow infiltration.

Technetium-99m 2-methoxyisobutylisonitrile (MIBI) imaging has been proposed as a front-line investigation to detect bone disease both before and after the treatment of myeloma. In this study, we have compared the pattern of MIBI uptake (focal and diffuse) between patients with proven myeloma and a cohort of patients without myeloma, in order to identify the uptake pattern that best correlates with disease activity.Nineteen scans were taken in 16 consecutive patients (nine males and seven females: aged 39-71 yr) with active myeloma. A further 20 scans (10 subjects having MIBI myocardial perfusion scintigraphy and 10 subjects having MIBI parathyroid adenoma localisation studies), comprised the control (non-myeloma) cohort. Scans were evaluated in a double-blinded fashion by two observers for any diffuse skeletal MIBI uptake (homogeneous uptake in spine, sternum and/or long bones), and/or abnormal focal uptake (patchy, focal or tubular uptake in the skeleton or soft tissues).The pattern of MIBI uptake was significantly different in the myeloma-positive subjects and the control cohort. Focal uptake was highly discriminatory, being seen in 15 of 19 (79%) scans of the myeloma-positive group as opposed to one of 20 (5%) scans of the control group (P0.0001). In contrast, diffuse uptake was seen in 17 of 19 (89%) scans in patients with myeloma, and in 11 of 20 (55%) of the control cohort (P = 0.02). Using multiple logistic regression analysis, any focal uptake was significantly predictive for active myeloma (P = 0.0007) but diffuse uptake was not (P = 0.15). Diffuse uptake alone, without focal uptake, was found in four of 19 scans with myeloma and in 10 of 20 without active myeloma, but was not significantly associated with absence of active myeloma (P = 0.06). Using the criteria of Pace et al. for positivity (diffuse activity50% myocardial activity), we demonstrated improved specificity from 45% to 100%, but significantly impaired sensitivity for presence of myeloma (79% vs. 37%, P = 0.02).Our study thus illustrates that the presence of any focal uptake of MIBI is useful in indicating active myeloma whereas diffuse uptake is not.

Introduction Congenital hypothyroidism (CH), as indicated by an elevation of capillary thyroid-stimulating hormone (TSH) at newborn screening, is a preventable cause of mental retardation with varying aetiology; it can be transient or permanent. Radionuclide assessment is currently the gold standard for imaging CH. This study aimed to (i) review the different scintigraphic patterns and correlate them with TSH levels/patient outcomes, (ii) assess the role of sonography in neonates with apparent agenesis as indicated by scintigraphy and (iii) develop a diagnostic investigative algorithm. Methods The technetium thyroid scans of 83 consecutive patients (49 females, average age 32 days) with CH scanned between 2005 and 2009 were retrospectively reviewed. Two nuclear medicine physicians blinded to the clinical details interpreted the scans in consensus. Scintigram appearances were categorised into five groups. Patients scintigraphically diagnosed with thyroid agenesis were evaluated with ultrasound. TSH values and scintigraphic and sonographic findings were correlated with patients' final diagnosis. Results Based on scintigraphy, 14, 13 and 19 patients out of 83 were assessed as having normal thyroid sites with normal, increased and decreased uptake, respectively. Twenty-two of 83 patients had no uptake, and 15 of 83 patients had ectopic uptake. Higher median TSH levels were seen in no-uptake and ectopic uptake subgroups. Eighteen of 22 patients with no uptake were evaluated with ultrasound. Three of the 18 patients had a normal thyroid gland, and three of 18 patients had a hypoplastic thyroid. Conclusion Scintigram findings in patients with congenital hypothyroidism fall into five major categories, which have therapeutic implications (lifelong thyroxine in agenesis versus trial of stopping thyroxine in other subgroups). Sonographic demonstration of thyroid tissue in patients scintigraphically diagnosed with thyroid agenesis has major management implications.