18F‐fluorodeoxyglucose positron emission tomography imaging in brain tumours: The Western Australia positron emission tomography/cyclotron service experience

¹⁸F‐fluorodeoxyglucose positron emission tomography (FDG‐PET) scans in the first 49 patients referred with either possible brain tumour or brain tumour recurrence were reviewed. FDG‐PET imaging was reported with reference to anatomical imaging. Based on the report the FDG study was classified as either positive or negative for the presence of tumour. Thirty‐eight cases were included in the analysis, 21 having pathological data and 17 with diagnostic clinical follow up. Eleven were excluded, as they had inadequate follow‐up data. Of the 21 cases with pathology, 18 were shown to have tumour. In this group there were five false‐negative scans and two false‐positive PET scans. Seventeen cases were assessed by clinical follow up, nine were considered to have been tumour. There were two false negatives with one false positive. The overall sensitivity, specificity and positive and negative predictive values were 74, 73, 87 and 53% respectively. This is similar to figures previously quoted in published work. Despite relatively limited numbers, the utility of FDG PET imaging in our hands is similar to published reports. With a positive predictive value of 87%, a positive FDG study indicates a high likelihood that there is brain tumour present. A negative study does not exclude the presence of tumour.     

Behavioral training increases local astrocytic metabolic activity but does not alter outcome of mild transient ischemia

Functional neurological outcome after transient ischemia might be improved by timely therapeutic intervention. To determine if restorative behavioral therapy influences damage, improves task learning, or alters astrocyte metabolic activity after ischemia, rats (food-restricted to 85% of free-feeding weight) were (a) first trained to respond on one of two levers under a fixed-ratio 20 schedule of food presentation (FR20), then (b) subjected to sham manipulation of carotid arteries or 10 min ischemia by four-vessel occlusion, followed by (c) 4 days of operant testing or inactivity, (d) then all rats were tested under a FR20 lever reversal task for 4 weeks, and (e) 3 days after the last behavioral session astrocyte metabolism was assayed by local uptake of [2-14C]acetate. Mild loss of hippocampal neurons occurred in ischemic rats with or without training after ischemia. Glial fibrillary acidic protein-positive astrocytes were present in similar numbers throughout brains of sham control and ischemic rats. Mild ischemia did not impair learning, and no changes in FR20 reversal learning were detected in sham vs. ischemic rats. Net [14C]acetate uptake was unaffected by ischemia but [14C]acetate uptake increased 15-24% (P<0.05; n=12-15/group) in specific structures (caudate, primary motor and sensorimotor cortex, CA1 hippocampus, subcortical white matter) in the pooled groups of rats that had 4 days FR20 testing vs. inactivity before reversal learning. 'Behavioral therapy' (operant testing on the 4 days immediately following either sham manipulation or ischemia) did not alter ischemic outcome, but was associated with higher acetate utilization in regions involved in motor activities.     

Immunologic changes during minimally invasive surgery

Although recent experimental and clinical trials have documented that postoperative inflammation and changes in different immunologic parameters are less pronounced after laparoscopic approaches in comparison to open surgery, it still remains unclear what influence the pneumoperitoneum itself has on immunologic defense and function. This is mainly due to the endpoints of the different studies which investigate changes in the so-called immunologic parameters (cell subunits, C-reactive protein, cytokines, catecholamines or other stress hormones in plasma samples) rather than analyzing immunologic functions, such as cell activation, production of proteins, cell proliferation or in vivo immune defenses. So far, especially in clinical trials, no correlation has been demonstrated between the changes in immunologic parameters and relevant postoperative clinical endpoints, such as postoperative complications. Thus further clinical prospective randomized studies with relevant clinical endpoints and additional investigations of immunologic parameters are needed to prove the consequences of either minimally invasive surgery or open procedures on postoperative immune functions.     

The experience of caring for older people with dementia in a rural area: using services

This paper reports findings from the carer component of the Gwynedd Dementia Study. It is based on carer interviews, using quantitative and qualitative data. It confirms earlier findings that carers for people with dementia are typically female and older than other carers, although it notes that caring husbands are amongst the oldest carers. The problems that are most common are those that cause psychological stress to carers. Carers were found to receive both help and appreciation from their families and to perceive neighbours to be helpful if needed. In Gwynedd, as elsewhere, levels of formal service inputs are low, but most of the carers appeared to receive the services they needed. Problems are primarily associated with crisis support and long-term care is accepted reluctantly. It is suggested that community care dementia specialists could play a supporting role for carers.     

MR imaging and proton MR spectroscopy in adult Krabbe disease

We present the MR imaging findings in four patients (two pairs of siblings from two unrelated families) with adult Krabbe disease. In the first family, clinical presentation mimicked familial spastic paraplegia. Their MR images showed selective, increased signal intensity on T2-weighted sequences along the corticospinal tracts, most prominently in the proband and barely detectable in her brother. Proton MR spectroscopy showed increased choline and myo-inositol in the affected white matter. In the second family, the clinical presentation differed in that the signs of pyramidal tract involvement were asymmetrical, with concomitant asymmetry on MR images in one. In adults, Krabbe disease may present on MR imaging with selective pyramidal fiber involvement.     

Undiagnosed adult diastematomyelia associated with neurological symptoms following spinal anaesthesia

Spinal anaesthesia is a safe, routinely performed procedure. However, in patients with lumbar cutaneous abnormities or deformities of the lower extremities, a previously undetected spinal anomaly may be present. In such patients, it may be prudent to avoid central neuraxial block to prevent neural damage. This instructive case presents such an adult patient in whom previously undiagnosed diastematomyelia, low conus and tethered cord was discovered only in the assessment of postspinal neurological symptoms.