Abstract-Positron emission tomography (PET) is a relatively lengthy brain imaging method. Because it is difficult for the subject to stay still during the data acquisition, head motion during scans is a source of image degradation. A simple data acquisition technique to reduce the effect of this problem is described. The technique associates the incoming data with the real-space position of the head. During the PET scan, the head position is constantly monitored with two video cameras and compared to its initial position. Every time the displacement for a region within the field of view (FOV) is larger than a specified threshold displacement, the PET data acquisition system starts to save the PET data in a new frame. The total number of frames required for a complete study depends on the magnitude of the head motion during the study and on the threshold displacement. At the end of the study, all the acquired frames are reconstructed independently and each image is rotated and translated to coincide with the initial position. When these images are summed, they produce a final image with fewer motion artefacts.
SummaryContext and ObjectiveNonfunctioning pituitary adenomas (NFPAs) are the most common subtype of pituitary tumour. Hypopituitarism is observed in NFPAs due to tumour‐ or treatment‐related factors and may increase mortality risk. Here, we analysed the associations of hypopituitarism, hormone replacement and mortality in a large NFPA cohort derived from two large European centres.Design, Setting and ParticipantsCase note review of all patients treated for NFPA in University Hospitals Birmingham and Beaumont Hospital Dublin between 1999 and 2014 was performed.Main Outcome MeasuresClinical presentation, treatment strategies, pituitary function and vitality status were recorded in each patient. A multivariate Cox regression model was used to examine the association between hypopituitarism, hormone replacement and premature mortality.ResultsA total of 519 patients were included in the analysis. Median duration of follow‐up was 7·0 years (0·5–43). A total of 81 deaths were recorded (15·6%). On multivariate analysis, adrenocorticotropic hormone (ACTH) and gonadotropin (Gn) deficiencies were associated with an increased relative risk of death (OR 2·26, 95% CI 1·15–4·47, P = 0·01 and OR 2·56, 95% CI 1·10–5·96, P = 0·01, respectively). Increased hydrocortisone (HC) (P‐trend = 0·02) and lower levothyroxine (LT4) doses (P‐trend = 0·03) were associated with increased risk of death. Mortality increased with the degree of pituitary failure observed (P‐trend = 0·04).ConclusionACTH and gonadotropin‐deficient patients have higher mortality rates compared to those with intact hormonal axes. Excessive HC and suboptimal LT4 replacement may also increase risk of death. Complex associations between hormone deficiency and replacement underpin the increased mortality risk in NFPA patients.
Data gathered from exploratory stimulation of the diencephalon in 130 stereotactic operative procedures have been studied, with the aid of a computer graphic technique, to show the position and topography of motor responses in the internal capsule. The results obtained indicate that pyramidal fibers are organized into a rostral-caudal face-arm-leg sequence and occupy a short compact band in the caudal third of the posterior limb of the internal capsule. This is in contrast to previous concepts of the position of these fibers in the capsule.
Pregnancy is rarely reported in acromegaly. Many patients are diagnosed in later life and younger patients may have subfertility due to hypopituitarism. We present a case series of 17 pregnancies in 12 women with acromegaly. Twelve women with acromegaly who completed pregnancy were identified from centres involved in the Irish Pituitary Study. Eleven women had pituitary macroadenomas and one woman had a microadenoma. Only 5/17 pregnancies had optimal biochemical control of acromegaly preconception, as defined by IGF-1 concentration in the age-related reference level and plasma GH concentration of <2 μg/L. In 6/17 pregnancies, dopamine agonist treatment was continued during pregnancy; all other acromegaly treatments were discontinued during pregnancy. Effect of pregnancy on acromegaly: No patient developed new visual field abnormalities, or symptoms suggestive of tumour expansion during pregnancy. In 9/12 patients, plasma IGF-1 concentrations that were elevated preconception normalised during pregnancy. There was a reduction in plasma IGF-1 concentrations, though not into the normal range, in a further two pregnancies. Effect of acromegaly on pregnancy: 15 healthy babies were born at term; one patient underwent emergency C-section at 32 weeks for pre-eclampsia, and one twin pregnancy had an elective C-section at 35 weeks' gestation. Blood pressure remained within normal limits in the remainder of the pregnancies. Gestational diabetes did not develop in any pregnancy. Our data suggests that pregnancy in women with acromegaly is generally safe, from a maternal and foetal perspective. Furthermore, biochemical control tends to improve despite the withdrawal of somatostatin analogue therapy during pregnancy.
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