Latex allergy in spina bifida patients.

Latex allergy has become a major problem in children with spina bifida, who need to undergo many major aggressive diagnostic and therapeutic procedures. Latex allergy is increasing in medical and surgical practice. Although early reports of latex allergy date from 1927, only over the last decade there has been more attention paid to latex allergy. This is due to an increasing number of reported cases of mild to fatal adverse reactions to latex. Risk groups have been identified; among these are patients undergoing multiple surgeries such as those with spina bifida. In this critical review, we aim to emphasize some aspects of the current management of surgical patients with latex allergy.

Latex allergy in neurosurgical practice.

The possibility of latex allergy and the implications of the potential life-threatening allergic reactions among patients (for example those with spina bifida), health care professionals, and latex industry workers are discussed. Latex allergy is becoming increasingly widespread in medical and surgical practice. Although early reports of latex allergy date from 1927, only over the last decade has more attention been paid to this condition. This is due to an increasing number of reported cases of adverse reactions to latex, varying in severity from mild to fatal. Latex allergy has become a major problem in children with spina bifida, who need to undergo many major aggressive diagnostic and therapeutic procedures. Risk groups have been identified and include patients having multiple surgical procedures, such as those with spina bifida. In this review we aim to emphasise some aspects of the current management of surgical patients with latex allergy.

Validity of stroke diagnosis on hospital discharge records in Saskatchewan, Canada: implications for stroke surveillance.

This study examines the validity of the diagnosis of stroke on hospital discharge records in Saskatchewan, Canada. In total, 1,494 records with a discharge diagnosis of 'stroke' or a 'stroke-related condition' were reviewed. The clinical algorithm of the 1980 USA National Survey of Stroke was considered the 'gold standard'. The positive predictive value of a primary diagnosis of stroke in the tertiary-care hospitals was about 90%. In community hospitals the majority of stroke cases were coded as ICD9 436 in which the positive predictive value was 78%. The variation between regions would limit the use of hospital discharge data for stroke surveillance.

Mobile tumours in the lumbar spinal canal: a diagnostic problem.

In two cases of mobile tumours in the lumbar spinal canal there was difficulty and delay in clinical and radiologic diagnosis because the early symptoms did not correspond to any particular dermatome. Myelography and computed tomography (CT) are the initial diagnostic procedures used in most institutions, even where magnetic resonance imaging (MRI) is available. The purpose of these 2 case reports is to remind clinicians that it is possible for certain tumours attached to the roots in the lumbar spinal canal to migrate, because the roots tend to be redundant or tax. Multilevel search is essential in neuroradiologic studies for early diagnostic confirmation of mobile tumours.

Parasellar epidermoid cyst presenting with subarachnoid hemorrhage.

The authors describe the clinical, radiologic and surgical findings for parasellar epidermoid cyst, which presented as subarachnoid hemorrhage in a 70-year-old woman. The cyst may have provoked the hemorrhage, an association reported only once before.

Hypothyroidism protects the brain during transient forebrain ischemia in gerbils.

The mechanisms by which brain cells die after brief episodes of cerebral ischemia are not fully understood. In certain brain regions this damage may not be apparent for days. Hypothyroidism is known to decrease cerebral metabolism. We postulated that this slowing in cerebral metabolism may be neuroprotective after transient cerebral ischemia. To test this hypothesis, a total of 10 gerbils had thyroidectomies performed 2 weeks prior to ischemia. Six gerbils served as euthyroid controls. All animals were exposed to 5 min of transient ischemia and sacrificed 7 days after the insult. Silver degeneration staining was used for histological evaluation. Hippocampal damage [subiculum (P < 0.001), CA1 (P = 0. < .001), CA3 (P < 0.05), and CA4 (P < 0.001)] was significantly less in the hypothyroid animals. There was also significantly less damage in the cerebral cortex (P < 0.05) and thalamus (P < 0.05) in the hypothyroid animals. The exact mechanism of this protection is not fully understood but could be secondary to a decrease in the metabolic activity, or a reduced generation of free radicals (as is seen with protection from ischemia in kidney and liver under hypothyroid conditions). Further studies are required in order to gain a better understanding of the protective effects of hypothyroidism on cerebral ischemia.

Very brief transient ischemic attack.

TIA is an important risk factor for ischemic stroke. Early diagnosis and management can result in a significant reduction in the risk of subsequent stroke. We report the case of a 54-year-old man who developed a 5-second episode of leg weakness and in whom a tight stenosis of the appropriate carotid artery was found. TIAs can sometimes be brief and have an atypical presentation, requiring a high level of suspicion for early diagnosis.

CGS-19755 is neuroprotective during repetitive ischemia: this effect is significantly enhanced when combined with hypothermia.

In small animals the damaging effects of repetitive ischemia are more severe than a single insult of similar duration. Prolonged release of glutamate may correlate with the degree of damage. We report the protective effects of CGS-19755 (an N-methyl-D-aspartate receptor blocker), hypothermia or CGS-19755 in combination with mild hypothermia, in a gerbil model of repetitive ischemia. We used 3 min of forebrain ischemia and repeated it for a total of three times as 1-h intervals. Damage was assessed seven days after the insult. In the group where only CGS-19755 was used, significant neuronal protection was evident in the hippocampus (CA1 and CA3), striatum, and medial geniculate nucleus. With hypothermia significantly less damage was seen in the cerebral cortex, hippocampus (CA1 and CA4), and substantia nigra reticulata. When CGS-19755 was combined with mild hypothermia the effects of repetitive ischemia were completely abolished in all but one gerbil. Compared to hypothermia alone, significant protection was seen in the cerebral cortex, hippocampus (sibiculum, CA1 and CA4), striatum, medial geniculate nucleus, thalamus, and substantia nigra reticulata. The use of N-methyl-D-aspartate receptor blockers may protect the brain in repetitive ischemia. Combination with hypothermia may further enhance this protection.

GABA agonist "muscimol" is neuroprotective in repetitive transient forebrain ischemia in gerbils.

The damaging effects from transient forebrain ischemia may be a result of excessive excitability or loss of inhibitory influences. In the brain, GABA acts as the major inhibitory neurotransmitter and its loss may be an important factor leading to delayed neuronal damage in the substantia nigra reticulata (SNr). In this study, we looked at the protective effects of muscimol, a GABA A agonist in a gerbil model of repetitive forebrain ischemia. For cerebral ischemia, we used three episodes of 2 min with a reperfusion period of 1 h between the insults. Histological evaluations were done 7 days after the insult using silver degeneration staining. Muscimol was infused into the third ventricle continuously for 7 days beginning just prior to the insult. There were a total of 20 animals, 12 treated with muscimol and the other 8 serving as controls. At 7 days, there was significant protection in the cortex (P = 0.007), hippocampus [CA1 (P = 0.01), CA4 (P = 0.015)], substantia nigra reticulata (P = 0.007), striatum (P = 0.049), and thalamus (P = 0.012). All statistical comparisons were done using nonparametric tests (Mann-Whitney U test). Our study shows that potentiation of inhibitory mechanisms may be important mechanisms of neuronal protection from the effects of repetitive ischemia and the effects are not limited to the SNr. Further studies are needed to better understand their mechanism of action.

Medullary hemorrhage causing vertigo and gaze nystagmus.

Brainstem hematomas carry a poor prognosis. There are rare reports of excellent outcome with hemorrhages in the midbrain. We report a 43-year-old woman with vertigo and minimal neurological symptoms, whose symptoms were initially mistaken for "inner ear disease," but subsequent investigations revealed a medullary hemorrhage. Recovery was complete within two weeks. While rare, medullary hemorrhage should be considered in the differential diagnosis of vertigo.

Flunarizine is effective in prophylaxis of headache associated with scleroderma.

Migraine-like headaches may occasionally be seen in patients with scleroderma. The mechanism of these headaches is not well established but may be secondary to central "Raynaud's phenomenon". We report a patient with such headaches that responded dramatically to the centrally acting calcium channel blocker, flunarizine. We suggest that flunarizine should be considered in the management of patients with scleroderma and migraine-like headaches.