Locked-in syndrome: a team approach

A person who suffers brainstem infarction resulting in quadriplegia, lower cranial nerve paralysis and mutism with intact cortical function may survive in a condition aptly termed "locked-in syndrome" (LIS). Literally a mind locked inside the body, the person remains fully aware without the ability to move or communicate. Because of the awesome nature of the condition and its likely permanent basis, family and staff may feel hopeless and incapacitated when planning care. Anatomical findings, etiologies, manifestations and outcomes are discussed in the literature but offer few suggestions for case management. Our clinical team has worked intensively with several LIS patients and has found that an interdisciplinary team approach is essential for providing creative patient care.

Relative growth and maturation of axon size and myelin thickness in the tibial nerve of the rat. 2. Effect of streptozotocin-induced diabetes

The relative changes in the growth and maturation of axon size and myelin thickness were studied in the medial plantar division of the tibial nerve in the lower leg and in the motor branches of the tibial nerve to the calf muscles in rats in which diabetes mellitus had been induced with streptozotocin at the time of weaning. Observations were made at 6 weeks and 3, 6, 9 and 12 months of diabetes for comparison with age-matched controls. Similar changes were observed in both nerves. Growth in body weight and skeletal growth was severely retarded from the time of induction of diabetes but at the 6-week stage axon size was not reduced, suggesting that neural growth may initially be relatively protected. At later stages axon size was consistently reduced in the diabetic animals as compared with the controls and showed an absolute reduction at 12 months, as compared with 9 months, that was greater than in the controls. Myelin thickness became reduced earlier and was more severely affected than axon size so that the fibers were relatively hypomyelinated. The myelin changes were greater in larger than in smaller fibers. The index of circularity of axons was reduced in the diabetic nerves. These results show that induction of diabetes in prepubertal rats produces effects on peripheral nerve fibers which differ from those resulting from diabetes induced in adult animals. The effects also differ between large and small nerve fibres. These observations may explain some of the disparate findings obtained in previous studies on experimental diabetes in rats.

Relative growth and maturation of axon size and myelin thickness in the tibial nerve of the rat. 1. Normal animals

Morphometric observations have been made on the medial plantar division of the tibial nerve (MPD) and on the motor branches of the tibial nerve to the calf muscles (MBC) in rats ranging in age from weaning (3 weeks) to 12 months. Axon size, assessed by measurements of circumference and cross-sectional area, increased rapidly until 3 months with further slight increases between 3 and 9 months and a slight fall between 9 and 12 months. Axon size distributions were unimodal throughout in the MPD but bimodal for the MBC except at 3 weeks. Distributions of myelin thickness were bimodal throughout for both nerves. Scatter plots of g ratios (axon diameter:total fibre diameter) confirmed the presence of two fibre populations: a group of small fibres with relatively thin myelin sheaths, and a group of larger fibres within which sheath thickness was relatively less on the larger than on the smaller axons. These two fibres populations were less easily separable in the MBC than in the MPD nerves. These results document morphometrically the normal growth changes in the rat tibial nerve and also provide control data for the analysis of the effects of experimental procedures on the growth and maturation of peripheral nerve fibres.

Descriptive writing abilities in Alzheimer's disease

The descriptive writing abilities of 15 subjects with Alzheimer's disease (AD) of mild to moderate severity were compared with 15 age- and sex-matched normal controls. Sixteen features of written linguistic ability were analyzed. AD subjects wrote shorter descriptive paragraphs than normal elderly subjects. Features related to letter or spelling errors and content words were found to be significantly different between the two groups, whereas functor word errors and number of attempted corrections did not significantly differ between the two groups.

The use of phonemic cueing with Alzheimer's disease patients

Variables influencing responsiveness to phonemic cueing, although studied extensively in the aphasia population, have not been identified in the Alzheimer's disease population. In this study, four variables were analyzed in relation to successfulness of phonemic cueing: severity of dementia, confrontational naming ability, auditory comprehension, and speech fluency. All three language measures showed a significant positive correlation with cueing. Severity of dementia showed a significant inverse correlation with responsiveness to cueing and was the best predictor of successful use of cueing. It was concluded that phonemic cueing aided in label retrieval, problematic in the early stages of Alzheimer's disease, prior to significant erosion of semantic meaning.

Enalapril and microalbuminuria in diabetic and non-diabetic hypertension

Nine patients with non-insulin-dependent diabetes mellitus (NIDDM) and ten non-diabetic patients with mild hypertension were treated with enalapril 20 mg daily. None had overt nephropathy, though 4 diabetic subjects had microalbuminuria. Subjects with the highest baseline albumin excretion rates (AER) showed the greatest fall on therapy. Metabolic control of diabetes did not deteriorate. Enalapril had no significant effect on AER in NIDDM patients with AER below 20 micrograms/minute or in the non-diabetic group.

MR imaging of heterotopic gray matter

Magnetic resonance imaging is the current method of choice to diagnose heterotopic gray matter and associated cerebral malformations. We report a case of an epileptic child in whom heterotopic gray matter is present without any associated ventricular distortion.

Antiherpesvirus activity of 9-(4-hydroxy-3-hydroxy-methylbut-1-yl)guanine (BRL 39123) in cell culture

The activity of 9-(4-hydroxy-3-hydroxymethylbut-1-yl)guanine (BRL 39123) against several herpesviruses was compared with that of acyclovir (ACV). In plaque reduction tests with clinical isolates of herpes simplex virus type 1 (HSV-1), herpes simplex virus type 2 (HSV-2), and varicella-zoster virus, mean 50% inhibitory concentrations (IC50S) (n = number tested) for BRL 39123 were 0.4 (n = 17), 1.5 (n = 13), and 3.1 (n = 5) micrograms/ml, respectively. Corresponding IC50S for ACV were 0.2, 0.6, and 3.8 micrograms/ml. Cytomegalovirus was relatively resistant to BRL 39123 (IC50, 51 micrograms/ml), but equid herpesvirus 1, bovid herpesvirus 2, and felid herpesvirus 1 were susceptible (IC50S, 1.6, 1.2, and 0.9 micrograms/ml, respectively). BRL 39123 was inactive against an HSV-1 strain which does not express thymidine kinase activity, but a DNA polymerase mutant selected for resistance to ACV was sensitive to BRL 39123 (IC50, 1.5 micrograms/ml). In contrast to the results from plaque reduction tests, BRL 39123 was more active than ACV against HSV-1 and of equal activity against HSV-2 in virus yield reduction assays in MRC-5 cells. After treatment of HSV-infected cultures for short periods, BRL 39123 was considerably more effective than ACV at reducing virus replication, and furthermore, after removal of extracellular BRL 39123, virus replication remained depressed for long periods, whereas such persistent activity was not observed with ACV. Neither compound significantly affected MRC-5 cell replication at 100 micrograms/ml, but at 300 micrograms/ml BRL 39123 was more inhibitory than ACV.

Determinants of mortality in pediatric patients with greater than 70% full-thickness total body surface area thermal injury treated by early total excision and grafting

Recent advancements in burn care have improved the survival rates of victims with severe burn injuries. The total mortality rate in a series of 1,057 pediatric patients admitted to Shriners Burns Institute Galveston Unit between 1982 and 1986 was 2.7%. The burn size resulting in a 50% death rate was 95% of the total body surface area (TBSA). In this study 19 survivors and 13 nonsurvivors with greater than 70% full-thickness TBSA burn injuries were compared. All survivors were adequately resuscitated upon arrival 11% sustained an inhalation injury. Forty-six per cent of the nonsurvivors sustained an inhalation injury; 31% were not initially adequately resuscitated. The presence of preadmission shock and inhalation injury were early determinants of mortality with secondary renal, pulmonary, or cardiovascular collapse being the later predictors of mortality in these massively burned pediatric patients.

Boxing injuries: neurologic, radiologic, and neuropsychologic evaluation

Boxing is an endeavor that may have to be re-evaluated in the coming years as to whether it should be designated as a sport. It is the only "sport" in which victory is determined by the amount of physical damage done to the opponent. We have presented the largest number of professional and amateur boxers (58) evaluated by various modern diagnostic modalities and have unequivocally demonstrated the deleterious effects of boxing upon the brain. There have been few, if any, meaningful actions taken by the promoters of boxing to correct the conditions under which boxers are subjected to physical abuse. Recommendations regarding the creation of a National Board of Boxing to supervise this "sport" have not been heeded. Suggested safeguards for the boxer, including mandatory medical and boxing history records (passports), use of headgear and approved safe boxing gloves, avoiding blows to the head, improved boxing ring floors, mandatory neurologic examinations, and more competent physicians at ringsides making medical decisions, have essentially not been implemented. The suggestions that mandatory computed tomograms at various stages in a boxer's career be used to determine possible changes of atrophy have not been followed, even when the CT scans have been made available at no cost to the boxers. The effective use of neuropsychologic evaluation, even when offered at no cost, has also been denied. The established medical injuries due to boxing and the lack of any sustained and significant efforts on the part of organized boxing create an atmosphere that is conducive to following the call for the consideration of a ban of boxing.