Proton MR spectroscopy (1 H-MRS) provides indices of neuronal damage in the central nervous system (CNS); however, it has not been extensively applied in the spinal cord. This work describes an optimized proton spectroscopy protocol for examination of the human cervical spinal cord. B 0 field mapping of the cord revealed periodic inhomogeneities due to susceptibility differences with surrounding tissue. By combining field maps and experimental data, we found that the optimum voxel size was 9 ؋ 7 ؋ 35 mm 3 placed with the inferior end of the voxel above vertebral body C2. Metabolite concentrations were determined in the cervical cord in six healthy controls by shortecho point-resolved spectroscopy (PRESS) volume localization. The results were compared with metabolite concentrations in the brainstem, cerebellum, and cortex in the same individuals. The concentrations in the cervical cord were as follows: Nacetyl-aspartate (NAA) 17.3 ؎ 0.5, creatine (Cr) 9.5 ؎ 0.9, and choline 2.7 ؎ 0.5 mmol/l. The NAA concentration was significantly lower in the cord than in the brainstem (Mann-Whitney, P < 0.025), and higher than in the cortex (P < 0.005) and cerebellum (P < 0.005). Cr was significantly lower in the cord than in the cerebellum (P < 0.05). There were no significant differences between Cr concentrations in the spinal cord compared to the cortex and brainstem.Magn Proton magnetic resonance spectroscopy ( 1 H-MRS) is a valuable noninvasive technique for assessing the biochemistry of the human brain. This is reflected by the increasing clinical applications of spectroscopy to investigate neurological disorders (1,2). Proton MRS of the brain has applications in multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), space-occupying lesions, and various metabolic disorders (3). However, in 10 -15% of MS patients (4) and in other diseases, such as ALS, the clinical picture is dominated by spinal cord pathology. Furthermore, diseases such as Friedreich's ataxia, compressive syndromes, subacute combined degeneration, and anterior spinal artery syndrome all principally affect the spinal cord.Spinal cord atrophy (an indirect marker of irreversible axonal loss within the spinal cord) has been shown to correlate with disability in MS (5). We have shown in both stroke (6) and MS (7) that with the use of small spectroscopy voxels to target the main pathways of the motor system (i.e., the posterior limb of the internal capsule), it is possible to demonstrate a correlation between N-acetylaspartate (NAA) levels and clinical measures of function within that pathway. This suggests that 1 H-MRS of the cord itself would reveal abnormalities in those diseases in which pathology is specific to the cord. This may provide information regarding neuronal viability, and thus provide physiological, diagnostic, and prognostic insights.It is technically challenging to perform spectroscopy on the spinal cord. The spinal cord is small compared to the size of the voxel in a typical spectroscopy examination, which limits the available signal-t...

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Unlike general practitioners, most hospital doctors do not use their car for work. Choice may therefore reflect individual character and aspirations. Although influenced by income and lifestyle, the ultimate decision may be determined by other less practical factors. At all price levels, some cars are more charismatic than others; the cost of this charisma is usually practicality. We have tested whether the 1960s stereotype of the dashing surgeon in a convertible sports car still exists. An extensive literature search drew a blank. Methods, analysis, and resultsAn anonymous questionnaire was distributed to 400 hospital doctors in three teaching hospitals in England and Wales in summer 1999. Respondents indicated their sex, grade, and specialty, and details of their main car: engine size, age (if more than 11 years, vintage or old banger), number of doors, and whether turbo charged, fuel injected, or soft topped. Anonymity ensured that specific cars could not be identified in the hospital car park. Make and model were not analysed owing to the diversity of cars now available. Although it was not asked about, many volunteered information about bicycles, rollerblades, etc.The "charisma score" of a car represents a useful comparative tool, independent of absolute cost, make and model. Although age and engine size are important, turbocharging, two doors, and a soft top are particularly potent. The "charisma score" was calculated by multiplying engine size (litres) by age factor and the weighting factors. Age was graded as 0-2 years (4 points), 3-5 years (3 points), 6-10 years (2 points), > 11 years (1 point) except vintage (10 points). Weighting factors were 5 for a soft top, 3 for turbo charged, 3 for two doors, 2 for fuel injection. Hatchback doors were not counted, and a sunroof does not equate to a soft top.Confounding factors included diesel cars (large engine size, often turbocharged) and small cars with only two doors. However, these cars did not score highly in other areas.A total of 221 questionnaires, representing all grades, were analysable (preregistration house officers, 25; senior house officers, 46; specialist registrar year 1-3, 28; specialist registrar year 4+, 36; consultants year 1-5, 30; consultants year 6+, 56; response rate 55%). Most specialties were represented: medicine, 100; surgery, 89; psychiatry, 8; laboratory based, 13; other, 11. Only 54 (24%) replies were from women-this was disappointing, as it is unrepresentative; however, a greater proportion of women volunteered the car colour.The mean charisma score for each grade (figure) and specialty (table) was calculated. Senior house officers scored highest (mean 57.7 points) and preregistration house officers lowest (16.1). The "top 20" ( > 96 points) were driven by 3 women and 17 men, comprising 7 senior house officers, 6 registrars, and 7 consultants (no preregistration house officers). All specialties were fairly represented: 8 surgeons, 8 physicians, 4 others.The "bottom 20" ( < 2.6 points) were also driven by 3 women and 17 men. There ...

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