Effect of CT-based attenuation correction on uptake ratios in skeletal SPECT

The aim of this study was to determine the clinical relevance of compensating SPECT data for patient specific attenuation by the use of CT data simultaneously acquired with SPECT/CT when analyzing the skeletal uptake of polyphosphonates (DPD). Furthermore, the influence of misregistration between SPECT and CT data on uptake ratios was investigated. Methods: Thirty-six data sets from bone SPECTs performed on a hybrid SPECT/CT system were retrospectively analyzed. Using regions of interest (ROIs), raw counts were determined in the fifth lumbar vertebral body, its facet joints, both anterior iliacal spinae, and of the whole transversal slice. ROI measurements were performed in uncorrected (NAC) and attenuation-corrected (AC) images. Furthermore, the ROI measurements were also performed in AC scans in which SPECT and CT images had been misaligned by 1 cm in one dimension beforehand (ACX, ACY, ACZ). Results: After AC, DPD uptake ratios differed significantly from the NAC values in all regions studied ranging from 32% for the left facet joint to 39% for the vertebral body. AC using misaligned pairs of patient data sets led to a significant change of whole-slice uptake ratios whose differences ranged from 3,5 to 25%. For ACX, the average left-to-right ratio of the facet joints was by 8% and for the superior iliacal spines by 31% lower than the values determined for the matched images (p <0.05). Conclusions: AC significantly affects DPD uptake ratios. Furthermore, misalignment between SPECT and CT may introduce significant errors in quantification, potentially also affecting leftto- right ratios. Therefore, at clinical evaluation of attenuation- corrected scans special attention should be given to possible misalignments between SPECT and CT.

Male infertility as a component of Carney complex

Carney complex (CNC) is a multiple neoplasia syndrome characterised by endocrine tumours, spotty skin pigmentation, cardiac and other myxomas, psamommatous and pigmented schwannomas, large cell calcifying Sertoli cell tumours, and mammary ductal adenomas and other more rare lesions. CNC is inherited in an autosomal-dominant manner and has been mapped to at least two chromosomal loci. Patients who map to the CNC1 locus located on chromosome 17 carry inactivating mutations of the PRKAR1A gene that encodes the cAMP-dependent protein kinase regulatory subunit type 1-alpha (Kirschner et al., 2000). One gene responsible for type 2 (CNC2) is located on chromosome 2p16. Infertility in CNC can be caused by a number of factors; there is evidence that prkar1a deficiency in mice leads directly to infertility (Burton et al., 2006), but patients with CNC also have Sertoli cell tumours and a number of other reasons to affect fertility. We report on an infertile male with CNC and present evidence that male infertility should be considered as part of the phenotype of CNC.

Effect of CT-based attenuation correction on uptake ratios in skeletal SPECT

The AIM of this study was to determine the clinical relevance of compensating SPECT data for patient specific attenuation by the use of CT data simultaneously acquired with SPECT/CT when analyzing the skeletal uptake of polyphosphonates (DPD). Furthermore, the influence of misregistration between SPECT and CT data on uptake ratios was investigated.

METHODS

Thirty-six data sets from bone SPECTs performed on a hybrid SPECT/CT system were retrospectively analyzed. Using regions of interest (ROIs), raw counts were determined in the fifth lumbar vertebral body, its facet joints, both anterior iliacal spinae, and of the whole transversal slice. ROI measurements were performed in uncorrected (NAC) and attenuation-corrected (AC) images. Furthermore, the ROI measurements were also performed in AC scans in which SPECT and CT images had been misaligned by 1 cm in one dimension beforehand (ACX, ACY, ACZ).

RESULTS

After AC, DPD uptake ratios differed significantly from the NAC values in all regions studied ranging from 32% for the left facet joint to 39% for the vertebral body. AC using misaligned pairs of patient data sets led to a significant change of whole-slice uptake ratios whose differences ranged from 3,5 to 25%. For ACX, the average left-to-right ratio of the facet joints was by 8% and for the superior iliacal spines by 31% lower than the values determined for the matched images (p < 0.05).

CONCLUSIONS

AC significantly affects DPD uptake ratios. Furthermore, misalignment between SPECT and CT may introduce significant errors in quantification, potentially also affecting left-to-right ratios. Therefore, at clinical evaluation of attenuation-corrected scans special attention should be given to possible misalignments between SPECT and CT.

Providing Complementary and Alternative Medicine in primary care: the primary care workers' perspective

BACKGROUND

The use of Complementary and Alternative Medicine (CAM) in primary care is growing, but still not widespread. Little is known about how CAM can/should be integrated into mainstream care.

OBJECTIVES

To assess primary care health professionals' perceptions of need and of some ways to integrate CAM in primary care.

METHOD

Questionnaire survey of primary health care workers in Northwest London. General Practitioners (GPs) were targeted in a postal survey, other members of the primary care team, such as district and practice nurses, were targeted via colleagues. The questionnaire assessed health care professionals' perspective on complementary medicine, referrals, ways to integrate complementary medicine into primary care and interest in research on CAM.

RESULTS

Responses were obtained from 149 GPs (40% response rate after one reminder) and 24 nurses and 32 other primary care team members. One hundred and seventy-one (83%) respondents had previously referred (or influenced referral) for CAM treatments, the main reasons cited were: patients request (68%), conventional treatments failed (58%) and evidence (36%) (more than one reason could be given). Acupuncture and homoeopathy were the therapies for which patients were most frequently referred, followed by manual therapies. There was a significant interest in more training/information on CAM (66%). Only 12 respondents (6%) were against any integration of CAM in mainstream primary care. Most respondents felt that CAM therapies should be provided by doctors (66%) or other health professionals trained in CAM (82%). Twenty-six percent of respondents agreed with provision of CAM by non-state-registered practitioners. It was felt that the integration of CAM could lead to cost savings (70%), particularly in conditions involving pain, but also cost increases (55%) particularly in 'poorly defined conditions'. Fifty-six percent of respondents would consider participating in studies investigating CAM. The greatest interest was in acupuncture (41% of those who expressed an interest in research), homoeopathy (30%) and therapeutic massage/aromatherapy (26%).

CONCLUSIONS

There is considerable interest in CAM among primary care professionals, and many are already referring or suggesting referral. Such referrals are driven mainly by patient demand and by dissatisfaction with the results of conventional medicine. Most of our respondents were in favour of integrating at least some types of CAM in mainstream primary care. There is an urgent need to further educate/inform primary care health professionals about CAM.

Frequency of CFTR gene mutations in males participating in an ICSI programme

A higher prevalence of cystic fibrosis transmembrane regulator (CFTR) gene mutations has been suggested both in men affected by congenital aplasia of the vas deferens, and in individuals presenting with reduced sperm quality. In this case, an increased risk for offspring being affected by cystic fibrosis (CF) can be expected in couples who are planning to undergo intracytoplasmic sperm injection (ICSI), since most of the male partners suffer from infertility. In order to determine the risk for these couples more precisely, we offered them a test for the most frequent CF mutations prevalent in the German population. The frequency of mutations within the CFTR gene in the female group was in the same range as expected for the general population (six out of 150). In 10 out of 207 males tested, infertility could be explained by exogenous factors not related to CFTR. Among the remaining 197 males with idiopathic infertility, we detected 13 heterozygotes for a mutation within the CFTR gene. This slightly, but significantly (P = 0.014), elevated rate could indicate that infertile males have, compared with the general population, an increased risk of being a carrier of a CFTR gene mutation.

Carcass composition and weight gain response of rats fed various carbohydrates at two dietary levels of carbohydrate and protein

A study was made of weight gains and carcass compositions in response to dietary sucrose, glucose, fructose, and corn starch at two dietary levels (40 and 60 %). Protein in the diets was either minimally adequate (12 %) or in excess of the requirement (18 %). At both carbohydrate and protein levels, sucrose-fed rats showed significantly greater weight gains than those animals receiving the other carbohydrates. At the 40-percent level, corn starch-fed animals gained more weight than animals receiving either glucose or fructose. At the 60-percent level, animals presented with fructose gained less weight than animals receiving the other carbohydrates. The animals receiving sucrose at both dietary levels had more carcass fat than those receiving either glucose or corn starch, and more carcass fat than those receiving fructose at the 60-percent level. An inverse relationship existed between carcass fat and carcass protein when both were expressed as a percentage of carcass dry weight. The fructose diets had protein retention values intermediate to those seen on the other diets. Protein retention on the sucrose diets was at least as high or higher than that on the starch diets. The results are consistent with the concept that different dietary carbohydrates elicit differing metabolic responses as measured by both weight gains and carcass analyses.