Intracranial hypertension after surgery in patients with Chiari I malformation and normal or moderate increase in ventricular size

OBJECTIVE

To determine ICP changes in patients with Chiari type I malformation after posterior fossa reconstruction (PFR).

PATIENTS AND METHODS

We continuously monitored ICP before and after PFR in 12 patients with Chiari I malformation and with an Evans' Index below or equal to 0.33. Mean ICP (epidural sensor) and percentage of B waves were calculated 24 hours before surgery and during the first 7 days after surgery.

RESULTS

Mean ICP and percentage of B waves significantly increased after surgery despite a significant increase in the volume of the posterior fossa. The main finding revealed by control CT scans was compression of the quadrigeminal cistern with a reduction in size of the fourth ventricle. In six patients, a small transitory increase in supratentorial ventricular size was found.

CONCLUSIONS

A transitory increase in ICP is common after PFR. This increase could be explained by an initial reperfusion phenomena in the cerebellum that provokes a transitory deterioration in CSF dynamics. The effacement of the quadrigeminal cistern and the reduction in size of the fourth ventricle suggests this hypothesis.

Agreement between CSF flow dynamics in MRI and ICP monitoring in the diagnosis of normal pressure hydrocephalus. Sensitivity and specificity of CSF dynamics to predict outcome

OBJECTIVES

The aims of the study were 1) to assess the degree of agreement between CSF flow dynamics determined by MR and ICP monitoring in the diagnosis of NPH, and 2) to determine the sensitivity and specificity of CSF flow dynamics studied by MR in predicting improvement after shunting.

PATIENTS AND METHODS

A prospective study was carried out in 35 consecutive patients with suspected NPH. CSF velocity (Phase Contrast) through the aqueduct was determined in sagittal plane. Patients were classified as "normal" or hyperdynamic in comparison with a control group of 27 healthy volunteers. Continuous extradural ICP monitoring was performed for at least 72 hours and patients were classified as having active, compensated, or ex-vacuo hydrocephalus. Patients with active or compensated hydrocephalus were shunted.

RESULTS

The degree of agreement between MR dynamics and ICP monitoring was 82%. Sensitivity of CSF velocity was 90% and specificity was 50%.

CONCLUSIONS

The degree of agreement between ICP monitoring and CSF velocity is high. High CSF velocity through the aqueduct is a good predictor of improvement after surgery. However, patients with normal velocity in MR required additional tests before a diagnosis of NPH is ruled out.

Morphometric study of testis of Wistar rat after open-ended vasectomy

The effects on the testis of open-ended vasectomy in the Wistar rat have been assessed morphometrically and evaluated statistically at 1, 4, 12, and 24 weeks after operation, and compared to those in sham-operated controls. The open-ended technique, ie, without ligation of the epididymal end of the cut ductus deferens, allowed drainage of sperm into the spermatic cord. During the period of our study, it did not affect the structure of the testis; although the germinal epithelium, basement membrane, and the stroma and cells of the interstitial space all showed variations when compared to the control group, these were not statistically significant.

[Arteriovenous malformations of the posterior fossa. Clinical features, treatment and results]

OBJECTIVES

We present our experience of 20 cases of arteriovenous malformations (MAV) of the posterior fossa.

PATIENTS AND METHODS

During the period 1991 1999 we prospectively collected radiological and therapeutic clinical data and the results obtained in all cases of adults whose arterio venous malformations were treated. We selected 20 of those who had MAV of the posterior fossa.

RESULTS

The average age was 39.6 years (15 64). Thirteen (65%) were men. Most patients, 16 cases (80%) presented clinically with cerebellar haemorrhage, subarachnoid and/or intraventricular haemorrhage and 6 (30%) of the patients were admitted in coma. On the Spetzler and Martin scale: grade 1, 1 patient (5%); grade 11, 8 patients (40%); grade 111, 8 patients (40%) and grade 1V, 3 patients (15%). One patient had an associated pedicular aneurysm, another a supratentorial MAV and another patient had several cavernomas. Nine patients required external ventricular drainage, which in 4 cases became a permanent CSF drainage system. Endovascular treatment was used in 8 patients, radiosurgery in 2 and surgery in 9. Complete resection of the MAV was only possible in the patients treated by surgery (two patients had been treated previously by embolizations and radiosurgery). In this series there was a mortality of 20%, in all four cases due to recurrence of bleeding. Good results were obtained in 11 (55%) of the patients, but in the other 5 (25%) there were sequelas.

CONCLUSION

The high percentage with haemorrhages as the form of presentation, with a much higher mortality than that of supratentorial MAVs makes more aggressive treatment necessary.

Private and social time preferences for health and money: an empirical estimation

The main objective of this paper is to examine the relationship between individual time preference for health and money. To that end, we tested whether individuals discount their own health at the same rate as their own money and, similarly, whether they discount social health in the same terms as social money. To offer private and social money and health choices is, to the best of our knowledge, new in the literature on the estimation of time preferences and, in our view, represents a valid way in which to respond to the question of the uniform or differential discount of health, as against monetary, consequences. The results of our estimation suggest that a sample of students exhibit higher time preference rates for health than money, this being the case when the exchanges are both private and public.

[Distal aneurysms of the vertebrobasilar system. A report of five cases]

INTRODUCTION

Aneurysms distal to the circle of Willis are uncommon. Among the rarest of such aneurysms are those found in the territory of the vertebrobasilar artery.

OBJECTIVE

To describe clinico-radiological aspects and the clinico-surgical evolution of five patients with distal aneurysms of the cerebellar arteries.

PATIENTS AND METHODS

Five patients (2.5%), with aneurysms of the cerebellar arteries, of a total of 194 patients with cerebral aneurysms admitted to our hospital between 1995 and 1998.

RESULTS

All patients presented with subarachnoid hemorrhage. One patient also had an arteriovenous malformation (AVM). One patient refused surgical treatment, three were treated surgically and one using the endovascular approach. The patient who was successfully treated using the endovascular approach to an aneurysm of the antero-inferior cerebellar artery, and who also had an AVM had a further episode of bleeding following partial embolization of his AVM. The patients who were treated surgically and the one who refused surgical treatment made good progress.

CONCLUSIONS

A multidisciplinary approach to the treatment of cerebral aneurysms is essential. Microsurgical techniques are very useful, especially in peripheral aneurysms.

[Hypertrophic pachymeningitis. A review of the histories of two cases and pathological relationship with the Tolosa-Hunt syndrome and the orbital pseudotumor]

INTRODUCTION

Hypertrophic pachymeningitis is an infrequent condition which starts with a thickening of the dura mater and whose pathogenesis is unknown. We present two new cases of unknown aetiology.

CLINICAL CASE

Case 1. A 53 year old man complained of occipital headache, tinnitus and deafness since February 1981. In October 1981 he was admitted to hospital with a worse headache, perio-orbital pain, dysgeusia and ipsilateral peripheral facial palsy. In December he had generalized tonic-clonic seizures and paralysis of the VII and XI right cranial nerves and IX, X and XII left cranial nerves. In February 1982 he developed right trigeminal neuralgia. He was readmitted in November 1983 with continuous headache, vomiting and a behavior disorder. On CT there was marked attenuation of the posterior dura mater, which the neurosurgical department considered unsuitable for biopsy. He died in March 1985. On necropsy there was hypertrophic pachymeningitis. Case 2. A 62 year old patient consulted in November 1995 complaining of right hypoacusia for the past six months, progressively accompanied by ipsilateral paralysis of the II, IV, VI, VII and VIII cranial nerves but with no other alterations on physical examination. Analytical and serological investigations were normal. Cranial MR showed an extraparenchymatous infiltrating lesion in the middle cranial fossa. Biopsy was decided on when no clinical improvement was seen with corticosteroid treatment. The pathologist reported hypertrophic pachymeningitis. Treatment was started with cyclophosphamide in monthly doses and the condition has remained stable to date.

CONCLUSION

With these two cases we wish to establish a pathogenic relation between the Tolosa-Hunt syndrome and orbital pseudotumor and show the role played by immunosuppressive treatment in the control of hypertrophic pachymeningitis.

Adverse drug reactions in children reported by means of the yellow card in Spain

OBJECTIVE

To analyze the case reports concerning children (14 years or younger) in the Spanish Pharmacovigilance System over a 10-year period (1982-1991).

FINDINGS

The study of 1419 reports of adverse drug reaction (9.8% of all those received) showed the most commonly involved organs and systems to be the skin, digestive tract, and nervous system (62.8%). The most commonly involved pharmacological groups were antibiotics, respiratory medications, and vaccines (69%). The absolute number of reports is higher in children between 1 and 4 years of age (37.9%). There were more reports among males than in females. Less than 5% of the reports notified directly life-threatening or fatal reactions.

CONCLUSIONS

Adverse drug reaction are not common in pediatric patients, and most are mild. However, due to limitations of clinical trials in children, pharmacoepidemiological studies may be the only source of information on the benefit-risk profile of drugs received by these patients, and as such require special attention.

[Subarachnoid hemorrhage, cerebral ischemia and endothelin-1]

INTRODUCTION

Cerebral vasospasm is involved in the development of delayed ischemic lesions in patients with subarachnoid hemorrhage. We developed an integral theoretical model to explain the pathophysiology of cerebral vasospasm, in which endothelin-1 has a pivotal role in the development of both cerebral vasospasm and delayed ischemic neurological deficits (DIND).

OBJECTIVE

The objective of this study is to analyze the relationship between temporal profile of plasma endothelin-1 levels and the development of cerebral vasospasm and DIND.

PATIENTS AND METHODS

We analyzed sequentially plasma endothelin-1 levels in 17 patients with aneurysmatic subarachnoid hemorrhage. All the patients had complete clinical and neuroradiological studies. Patients were classified according to Fisher's score.

RESULTS

Patients (4 males and 13 females, aged 48.1 +/- 20.3 years) had a good clinical condition (Hunt-Hess < 4, GCS > 10). Two weeks after bleeding, patients had higher plasma endothelin-1 levels than healthy volunteers (p = 0.024). Patients who developed DIND had higher plasma endothelin-1 levels (p = 0.034) and a different evolution (p = 0.0146) than patients without DIND. There is a significant correlation (p = 0.02) between basal plasma endothelin-1 levels and GOS score. Multiple regression analysis shows a significant dependence between plasma endothelin-1 levels and Fisher's score (p = 0.0195), development of DIND (p = 0.0095), and GOS score (p = 0.0319). Logistic regression analysis finds a predictive relation between Fisher's score and plasma endothelin-1 levels for the development of DIND (overall predicted = 74.24%; p = 0.0148).

CONCLUSIONS

Plasma endothelin-1 levels are increased in patients after subarachnoid hemorrhage and are associated with the development of cerebral vasospasm and DIND.

Regio- and Diastereoselective Aldol Products through Three-Component Coupling Reactions of Difluoroboroxy Fischer Carbene Molybdenum Complexes

The reaction of difluoroboroxy Fischer carbene complexes, vinyl ketones, and aldehydes leads to the regioselective formation of aldol-like products (see reaction scheme). The reaction also shows a high degree of diastereofacial selectivity when chiral aldehydes are used. These results show that this is a very attractive process since the regioselective formation of aldols from nearly symmetrical ketones still remains an unsolved problem.

The effects of histamine on the isolated mouse uterus

1. A study is made of the contractile and relaxant effects, and mechanism of action, of histamine on isolated uterus from mice treated with diethylstilboestrol, employing acetylcholine and adrenaline as contractile and relaxant standard agents. 2. Concentration-response curves for histamine agonists were obtained in the absence and presence of selective histaminergic blocking drugs (clemizole, ranitidine and thioperamide) and indomethacin. A number of experiments were carried out in uterus from reserpinised mice. Concentration-response curves for acetylcholine and adrenaline were also obtained in the absence and presence of their selective antagonist (atropine and propranolol). 3. In isolated oestrogenised mouse uterus, histamine and acetylcholine produced a concentration-related contractile response. When the uterus was precontracted with KCl, histamine at lower doses produced a slight contraction, though in the presence of clemizole it induced concentration-related relaxation, reminiscent of that produced by adrenaline. Atropine and propranolol antagonised the contractile and relaxant effects of acetylcholine and adrenaline, respectively. 4. In isolated uterus from reserpinised mice, histamine and 2-pyridylethylamine, but not 4-methylhistamine, produced a concentration-related contractile response. Ranitidine potentiated the contractile effect of histamine, though clemizole--in the presence of ranitidine--competitively antagonised the contractile effect of histamine (pA2 = 10.50 +/- 0.81). The concentration-relaxant curve of histamine in the presence of clemizole was not modified by ranitidine or indomethacin, but shifted to the right with thioperamide. The same displacement was also observed in the presence of clemizole plus ranitidine. 5. In mouse isolated uterus, histamine mainly produced contraction mediated by histamine H1-receptors, though the existence of histamine H2- or H3-receptors mediating relaxation could not be excluded.

beta-Trace protein in human cerebrospinal fluid: a diagnostic marker for N-glycosylation defects in brain

As carbohydrate-deficient glycoprotein syndromes (CDGS) are multisystemic disorders with impaired central nervous function in nearly all cases, we tested isoforms of beta-trace protein (beta TP), a 'brain-type' glycosylated protein in cerebrospinal fluid (CSF) of nine patients with the characteristic CDGS type I pattern of serum transferrin. Whereas the serum transferrin pattern did not discriminate between the various subtypes of CDGS type I (CDGS type Ia, type Ic, and patients with unknown defect), beta TP isoforms of CDGS type Ia patients differed from that of the other CDGS type I patients. The percentage of abnormal beta TP isoforms correlated with the severity of the neurological symptoms. Furthermore, two patients are described, who illustrate that abnormal protein N-glycosylation can occur restricted to either the 'peripheral' serum or the central nervous system compartment. This is the first report presenting evidence for an N-glycosylation defect restricted to the brain. Testing beta TP isoforms is a useful tool to detect protein N-glycosylation disorders in the central nervous system.

A prospective study of adverse drug reactions in hospitalized children

AIMS

There are few publications of adverse drug reactions (ADRs) among paediatric patients, though ADR incidence is usually stated to be higher during the first year of life and in male patients. We have carried out a prospective study to assess the extent, pattern and profile risk for ADRs in hospitalized patients between 1 and 24 months of age.

METHODS

An intensive events monitoring scheme was used. A total of 512 successive admissions to two medical paediatric wards (47 beds) were analysed. The hospital records were screened daily during two periods (summer, 105 days and winter, 99 days), and adverse clinical events observed were recorded.

RESULTS

A total of 282 events were detected; of these, 112 were considered to be manifestations of ADRs. The cumulative incidence was 16.6%, no differences being observed between periods. Although there were no differences between patients under and over 12 months of age, risk was found to be significantly higher among girls compared with boys (RR=1.66, 95% CI 1.03-2.52). The gastro-intestinal system was most frequently affected. The therapeutic group most commonly implicated was anti-infective drugs and vaccines (41.5%). The ADRs were mild or moderate in over 90% of cases. A consistent relationship was noted between the number of drugs administered and the incidence of ADRs.

CONCLUSIONS

Hospitalized patients exhibited an ADR risk profile that included female sex and the number of drugs administered. No particular age predisposition was observed. The most commonly prescribed drugs are those most often implicated in ADRs in paediatric patients.

Interhemispheric supratentorial intracranial pressure gradients in head-injured patients: are they clinically important?

OBJECT

It is generally accepted that the intracranial compartment behaves as a unicameral space in which intracranial pressure (ICP) is uniformly distributed. However, this concept has been challenged many times. Although there is general agreement on the existence of craniospinal and suprainfratentorial gradients, the existence of interhemispheric gradients is still a matter of debate. The object of this study was to reexamine the issue of interhemispheric supratentorial ICP gradients in patients with head injuries and the clinical significance of these gradients in their management.

METHODS

The authors present the results of a prospective study conducted in 50 head-injured patients to determine the clinical significance of supratentorial ICP gradients. In each case a concurrent bilateral frontal intraparenchymatous device was implanted within the 6-hour window after computerized tomography (CT) scanning. According to CT criteria, each patient was categorized into one of three different groups: 1) diffuse lesions, in which no unilaterally measured volumes greater than 25 ml were present and the midline shift was 3 mm or less; 2) Focal A, in which added hemispheric volumes were greater than 25 ml and midline shift was 3 mm or less; and 3) Focal B, in which all patients with a midline shift greater than 3 mm were included. From the results of the entire group the authors were able to distinguish four different patterns of supratentorial ICP. In Pattern I, the intracranial compartment behaved as a true unicameral space with similar mean ICPs and pulse amplitudes in both hemispheres; in Pattern II, different mean ICPs and amplitudes were observed although ICP increases or decreases were congruent; and in Pattern III, patients with different mean ICPs, different ICP amplitudes, and no congruent increases or decreases of ICP were included. All (15 cases) but one patient with a diffuse lesion presented with ICP Pattern I. Fifteen patients with focal lesions showed a Type II pattern, whereas only one patient presented with a Type III pattern. In 10 patients, of whom all but one presented with a focal lesion, transient gradients that disappeared in less than 4 hours were also observed.

CONCLUSIONS

In many patients with focal lesions, clinically important interhemispheric ICP gradients exist. In this subset, transient gradients that disappear with time are frequently observed and may indicate an increase in the size of the lesion. The clinical relevance of such gradients is discussed and guidelines for adequately monitoring ICP are suggested to optimize head injury management and to avoid suboptimal or even harmful care in patients with mass lesions.

Incidence of intracranial hypertension after severe head injury: a prospective study using the Traumatic Coma Data Bank classification

Intracranial hypertension (ICH) is a frequent finding in patients with a severe head injury. High intracranial pressure (ICP) has been associated with certain computerized tomography (CT) abnormalities. The classification proposed by Marshall et al. based on CT scan findings, uses the status of the mesencephalic cisterns, the degree of midline shift, and the presence or absence of focal lesions to categorize the patients into different prognostic groups. Our aim in this study was to analyze the ICP evolution pattern in the different groups of lesions of this classification.

PATIENTS AND METHODS

We present the results of a prospective study in 94 patients with severe head injury, in whom ICP was monitored for at least 6 hours. ICP evolution was classified into three different categories: 1) ICP always < 20 mm Hg, 2) Intracranial hypertension at some time during monitoring, but controlled by medical or surgical treatment, 3) Uncontrollable ICP. The ICP pattern was correlated with the final CT diagnostic category.

CONCLUSIONS

3 patients had a normal CT scan, and none of them presented intracranial hypertension. In diffuse injury type II, the ICP evolution may be quite different. Patients with bilateral brain swelling (Diffuse Injury III) have a high risk of increased ICP (63.2%). Although in our study the frequency of Diffuse Injury IV was low, all patients in this category had a refractory ICP. In the category of evacuated mass lesions, two thirds of the patients presented an intracranial hypertension. In one third, ICP was refractory to treatment. 85% of patients with a non-evacuated mass lesion showed an increased ICP.

Modulation of the chaperone heat shock cognate 70 by embryonic (pro)insulin correlates with prevention of apoptosis

Insights have emerged concerning insulin function during development, from the finding that apoptosis during chicken embryo neurulation is prevented by prepancreatic (pro)insulin. While characterizing the molecules involved in this survival effect of insulin, we found insulin-dependent regulation of the molecular chaperone heat shock cognate 70 kDa (Hsc70), whose cloning in chicken is reported here. This chaperone, generally considered constitutively expressed, showed regulation of its mRNA and protein levels in unstressed embryos during early development. More important, Hsc70 levels were found to depend on endogenous (pro)insulin, as shown by using antisense oligodeoxynucleotides against (pro)insulin mRNA in cultured neurulating embryos. Further, in the cultured embryos, apoptosis affected mainly cells with the lowest level of Hsc70, as shown by simultaneous Hsc70 immunostaining and terminal deoxynucleotidyltransferase-mediated UTP nick end labeling. These results argue in favor of Hsc70 involvement, modulated by embryonic (pro)insulin, in the prevention of apoptosis during early development and suggest a role for a molecular chaperone in normal embryogenesis.