Showing papers by "Hebron University published in 2000"

Isolated demyelinating syndromes : Comparison of different MR imaging criteria to predict conversion to clinically definite multiple sclerosis

Abstract: BACKGROUND AND PURPOSE: Various authors have developed criteria to classify MR imaging findings that suggest the possibility of multiple sclerosis. The purpose of this study was to evaluate and compare the capacity of three sets of MR imaging criteria for predicting the conversion of isolated demyelinating syndromes to clinically definite multiple sclerosis. METHODS: Seventy patients with clinically isolated neurologic symptoms suggestive of multiple sclerosis were prospectively studied with MR imaging. The MR imaging findings were evaluated by two independent neuroradiologists who were blinded to clinical follow-up data. Based on the clinical outcome at follow-up (presence of a second attack that established clinically definite multiple sclerosis), the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the criteria proposed by Paty et al, Fazekas et al, and Barkhof et al were calculated. RESULTS: Clinically definite multiple sclerosis developed in 22 (31%) patients after a mean follow-up time of 28.3 months. The criteria proposed by Paty et al and those proposed by Fazekas et al showed identical results: sensitivity, 86%; specificity, 54%; accuracy, 64%; positive predictive value, 46%; and negative predictive value, 89%. The criteria proposed by Barkhof et al showed the following: sensitivity, 73%; specificity, 73%; accuracy, 73%; positive predictive value, 55%; and negative predictive value, 85%. CONCLUSION: The four dichotomized MR imaging parameters proposed by Barkhof et al are more specific and accurate than the criteria proposed by Paty et al or Fazekas et al for predicting conversion to clinically definite multiple sclerosis.

ZD1839 (‘Iressa’)1,2 as an Anticancer Agent

Abstract: ZD1839 (‘lressa’)1,2 is an orally active, selective epidermal growth factor receptor-tyrosine kinase inhibitor which blocks signal transduction pathways implicated in the proliferation and survival of cancer cells and other host-dependent processes promoting cancer growth. In preclinical studies, ZD1839 produced reversible growth inhibition and growth delay in a wide range of tumour cell lines and human tumour xenografts. Moreover, this activity was enhanced when ZD1839 was coadministered with cytotoxic agents. Preliminary results from phase I trials in patients with advanced disease and a wide variety of tumour types suggest that ZD1839 has an acceptable tolerability profile and promising clinical efficacy, particularly in non-small cell lung cancer (NSCLC). ZD1839 is currently in phase III clinical development for the treatment of advanced NSCLC. In addition, further trials are ongoing or planned in a number of other tumour types.

The orthopaedic status of severe haemophiliacs in Spain

Abstract: Summary. This paper provides an outline of the results obtained in a cross-sectional study conducted primarily with the aim of ascertaining orthopaedic complications in a group of young severe A and B haemophiliacs, the effects which these complications have on the medical resources used with these patients, and the impact of severe haemophilia on their quality of life. Its secondary aim was to link their current orthopaedic status to the type of treatment they had received prior to the study. Eleven Spanish hospitals took part in this study, monitoring 70 severe haemophiliacs (FVIII:C 6 months). In 40 cases (57.1%) the patients underwent one or more periods of prophylaxis. Thirty-three patients (47.8%) had over 1000 days of administration of factors VIII and IX. The analysis of the total study group reveal an average of 348 bleeding episodes per patient. The findings of this study revealed that 84.3% of these patients suffer from articular complaints on the Gilbert scale, and 85.7% on the Pettersson scale. In addition, pain was reported in 16.1% of the joints, the most frequently affected being the ankle joints. Twenty-six patients (37%) had undergone orthopaedic surgery from the time of birth to the conclusion of the study. The quality of life of the severe haemophiliacs reviewed seems to have been affected. During the last 12 months, there were 216 outpatient haematological visits and 176 orthopaedicrehabilitation visits, as well as 12 radiological explorations and two hospitalizations. During these 12 months, medical expenditure totalled $55 473 per patient per year, the most important item being factor concentrates VIII/IX ($54 119 per patient per year). The type of treatment given to these patients (on-demand and/or as secondary prophylaxis) was found to be incapable of preventing haemophilic arthropathy or guaranteeing an acceptable quality of life, although both the administration of coagulant factor concentrate to such patients and the financial resources dedicated to their treatment was very high. Consequently, a strategic change is to be considered for the prevention of haemophilic arthropathy, based on the introduction of replacement treatment involving continuous administration of factors VIII and IX in primary prophylaxis regimens from the first years of life.

Cerebral hemodynamic effects of 7.2% hypertonic saline in patients with head injury and raised intracranial pressure.

Abstract: The aim of the present study was to investigate the acute effects of 7.2% hypertonic saline (HS) on intracranial pressure (ICP), cerebral and systemic hemodynamics, serum sodium, and osmolality in 14 patients with moderate and severe traumatic brain injury (Glasgow Coma Scale ≤13) and raised ICP (>15 mm Hg) within the first 72 h postinjury. After CO2 reactivity and autoregulation were tested, each patient received a 15-min infusion of 7.2% HS (1,232 mEq/L, volume 1.5 mL/kg). ICP, serial hemodynamics, cerebral blood flow (CBF) estimated from cerebral arteriovenous oxygen content difference (AVDO2), and laboratory variables, including serum osmolality, electrolytes, urea, and creatinine were collected before infusion (T0) and at 5, 30, 60, and 120 min after (T5, T30, T60, T120). Urine output was measured 2 h before infusion and at T120. While CO2 reactivity was preserved in all patients, autoregulation was preserved in only four. ICP decreased to about 30% of base line (p = 0.0001) during the whole...

Cerebral hemodynamic effects of morphine and fentanyl in patients with severe head injury: absence of correlation to cerebral autoregulation.

Abstract: Background The current study investigates the effects of morphine and fentanyl upon intracranial pressure and cerebral blood flow estimated by cerebral arteriovenous oxygen content difference and transcranial Doppler sonography in 30 consecutive patients with severe head injury in whom cerebrovascular autoregulation previously had been assessed. Methods Patients received morphine (0.2 mg/kg) and fentanyl (2 microg/kg) intravenously over 1 min but 24 h apart in a randomized fashion. Before study, carbon dioxide reactivity and autoregulation were assessed. Intracranial pressure, mean arterial blood pressure, and cerebral perfusion pressure were repeatedly monitored for 1 h after the administration of both opioids. Cerebral blood flow was estimated from the reciprocal of arteriovenous oxygen content difference and middle cerebral artery mean flow velocity using transcranial Doppler sonography. Results Although carbon dioxide reactivity was preserved in all patients, 18 patients (56.7%) showed impaired or abolished autoregulation to hypertensive challenge, and only 12 (43.3%) had preserved autoregulation. Both morphine and fentanyl caused significant increases in intracranial pressure and decreases in mean arterial blood pressure and cerebral perfusion pressure, but estimated cerebral blood flow remain unchanged. In patients with preserved autoregulation, opioid-induced intracranial pressure increases were not different than in those with impaired autoregulation. Conclusions The authors conclude that both morphine and fentanyl moderately increase intracranial pressure and decrease mean arterial blood pressure and cerebral perfusion pressure but have no significant effect on arteriovenous oxygen content difference and middle cerebral artery mean flow velocity in patients with severe brain injury. No differences on intracranial pressure changes were found between patients with preserved and impaired autoregulation. Our results suggest that other mechanisms, besides the activation of the vasodilatory cascade, also could be implicated in the intracranial pressure increases seen after opioid administration.

Cognitive changes after cerebrospinal fluid shunting in young adults with spina bifida and assumed arrested hydrocephalus

Abstract: Objectives—To establish whether surgery can improve the neuropsychological functioning of young adult patients with spina bifida and apparent clinically arrested hydrocephalus showing abnormal intracranial pressure. Methods—Twenty three young adults with spina bifida and assumed arrested hydrocephalus (diagnosed as active or compensated by continuous intracranial pressure monitoring) underwent surgery. All patients received neuropsychological examination before surgery and 6 months later. Neuropsychological assessment included tests of verbal and visual memory, visuospatial functions, speed of mental processing, and frontal lobe functions. Results—Shunt placement in this subgroup of patients improves neuropsychological functioning, especially in verbal and visual memory and attention and cognitive flexibility. Conclusions—Young adults with spina bifida and suspected non-functioning shunt or non-shunted ventriculomegaly should be carefully monitored to identify those who could benefit from shunting. (J Neurol Neurosurg Psychiatry 2000;68:615‐621)

Vertebral artery occlusion after acute cervical spine trauma.

Abstract: STUDY DESIGN: A retrospective study of vertebral artery injury diagnosed during the last 6 years in our institution. OBJECTIVES: To determine the clinical and radiologic features of vertebral artery injury. SUMMARY OF BACKGROUND DATA: Extracranial occlusion of the vertebral artery associated with cervical spine fracture is uncommon and can cause serious and even fatal neurologic deficit due to back lifting and cerebellar infarction. Magnetic resonance imaging and magnetic resonance angiography are extremely helpful in the examination of acute injuries of the cervical spine. METHODS: Magnetic resonance imaging and magnetic resonance angiography were performed at the time of injury. RESULTS: The authors reviewed six patients with cervical spine fractures who were diagnosed with a unilateral occlusion of the vertebral artery by means of magnetic resonance imaging/magnetic resonance angiography. One patient had signs of vertebrobasilar insufficiency and another with complete cord lesion had cerebellar and back lifting infarctions. Surgical anterior spinal fusion was performed in five patients, and one was treated by traction and orthosis. At the time of discharge, five patients had no vertebrobasilar symptoms, and the patient who experienced vertebrobasilar territory infarctions showed no progression of the neurologic damage. CONCLUSIONS: Vertebral artery injury should be suspected in cervical trauma patients with facet joint dislocation or transverse foramen fracture. Magnetic resonance imaging/magnetic resonance angiography is a helpful test to rule out vascular injury. Vertebral artery injury affects the extracranial segment at the same level as the cervical fracture. This is a retrospective review that did not permit drawing conclusions about the effects of early surgical stabilization in the treatment of cervical spine injuries with associated vertebral artery injury; however, surgical stabilization may avoid propagation and embolization of the clot located at the site of the lesion.

Abnormalities of erythrocyte membrane fluidity, lipid composition, and lipid peroxidation in systemic sclerosis: evidence of free radical-mediated injury.

Abstract: Objective To elucidate whether oxidative injury occurs in systemic sclerosis (SSc) and whether it affects the erythrocyte membrane (EM) properties. Methods EM fluidity and lipid composition (cholesterol:phospholipid molar ratio [C:PL], fatty acid composition) were studied in 52 patients with SSc and in 53 subjects without SSc (32 with primary Raynaud's phenomenon [RP] and 21 healthy subjects [controls]). Fluidity was measured as the fluorescence anisotropy of the hydrophobic fluorescent probe DPH (1,6-diphenyl-1,3,5-hexatriene). Lipid peroxidation products were determined as thiobarbituric acid–reactive substances (TBARS). Results EM fluidity was significantly lower in SSc patients than in primary RP patients and controls (P < 0.001). The EM C:PL molar ratio was significantly higher in SSc patients than in primary RP patients and controls (P < 0.05). Levels of EM polyunsaturated n6 fatty acids (PUFA n6) were significantly lower in SSc patients than in primary RP patients and controls (P < 0.001). TBARS were significantly increased in SSc patients compared with primary RP patients and controls (P < 0.001). Multiple regression analyses indicated that the reduced EM fluidity was partly due to its greater C:PL molar ratio, lower PUFA n6 content, and higher TBARS levels. EM fluidity was lower among patients with nailfold capillary loss (P < 0.001) and digital ischemic ulcers (P < 0.05). EM lipid peroxidation products were higher among patients with pulmonary involvement (bibasal pulmonary fibrosis [P < 0.05] and reduced levels of diffusing capacity for carbon monoxide [P < 0.001]) and among patients who were positive for anti–topoisomerase I antibodies (P < 0.05) or negative for anticentromere antibodies (P < 0.001). Conclusion Our findings support the idea that oxidative injury occurs in SSc and that, through lipid peroxidation, it induces structural and functional changes of the EM that may contribute to the development of the microvascular abnormalities that are seen in the disease.

Does an Increase in Cerebral Perfusion Pressure Always Mean a Better Oxygenated Brain? A Study in Head-Injured Patients

Abstract: The adequate management of cerebral perfusion pressure (CPP) continues to be a controversial issue in head-injured patients. The purpose of our study was to test two hypotheses. The first was that in patients with a CPP below 70 mm Hg, oxygen delivery is compromised and that therefore signs of tissue hypoxia would be reflected in low PtiO2 measurements. The second hypothesis was that manipulating mean arterial blood pressure to increase CPP improves oxygen delivery, particularly in patients with a CPP below 70 mm Hg. Twenty-five moderately or severely head-injured patients were included in the study. In all of them PtiO2 was monitored in the noninjured hemisphere using the Licox system (GMS, Kiel-Mielkendorf, Germany). Arterial hypertension was induced with phenylephrine 29 times. To quantify the effect of increasing mean arterial blood pressure (MABP) on oxygen delivery to the brain, the PtiO2-BP index was calculated (PtiO2-BP index = ΔPtiO2/ΔMABP). In 16 tests (55%) baseline CPP was above or equal to 70 mm Hg and in the remaining 13 (45%) it was below 70 mm Hg. Mean increase in MABP after phenylephrine was 23.7 ± 10.2 mm Hg. Mean PtiO2 was 29.5 ± 14.7 mm Hg in patients with a basal CPP of below 70 mm Hg and 28.9 ± 10.6 mm Hg in patients in the high CPP group. These differences being not statistically significant. The PtiO2VBP index was 0.29 ± 0.23 in patients with a basal CPP of below 70 mm Hg and in patients with a CPP of above 70 mm Hg this index was 0.16 ± 0.11 Hg. These differences were not statistically significant (Student’s t-test, P = 0.09). In our study a low PtiO2 was not observed in patients with marginally low CPPs (48–70 mm Hg) and readings below 15 mm Hg were observed in cases with both normal or supranormal CPPs. We conclude that episodes of low PtiO2 could not be predicted on the basis of CPP alone. On the other hand, raising CPP did not increase oxygen availability in the majority of cases, even if the CPP was markedly improved.

False autoregulation (pseudoautoregulation) in patients with severe head injury. Its importance in CPP management.

Abstract: False autoregulation has been described as an alteration of autoregulation in which the apparent maintenance of a constant cerebral blood flow (CBF) when increasing cerebral perfusion pressure (CPP) is due to an increase in brain tissue pressure. The objective of our study was to investigate how often false autoregulation occurred in patients with a severe head injury. In forty-six patients with a moderate or severe head injury autoregulation was studied using arterio-jugular differences of oxygen (AVDO2) to estimate changes in CBF after inducing arterial hypertension with phenylephrine. Changes in mean arterial blood pressure (MABP), intracranial pressure (ICP), cerebral perfusion pressure (CPP) and AVDO2 were calculated before and after inducing hypertension. Ninety-five episodes of provoked hypertension were studied in 46 patients. In 28 tests (29.5%) a constant or even reduced CBF was detected simultaneously with a median increase in parenchymal ICP of 8.5 mm Hg (false autoregulation). In this group the median of the induced increase in MABP was 20.6 mm Hg with a median increase in CPP of 11.5 mm Hg. From our data we can conclude that false autoregulation is frequently found in patients after a severe head injury. Increasing MABP to obtain a better CPP in these patients is not beneficial because CBF is not modified or may even be reduced.

Partial epiglottectomy as a possible treatment for globus pharyngeus

Abstract: Globus pharyngeus is a relatively common complaint in an ear, nose, and throat consulting room and may account for 3–4% of outpatient referrals. The cause is still unknown, although a number of hypotheses have been suggested. Between 40% and 75% of the patients remain symptomatic despite any treatment regimen. Thirteen patients from a group of 124 with the diagnosis of globus pharyngeus and no response to medical treatment were treated with partial epiglottectomies. One year after the surgery all but one patient were free of symptoms. Our experience indicates that partial epiglottectomy can be a good treatment for those patients with globus pharyngeus in whom no cause is found after all studies are performed or when medical treatment fails.

Atlanto axial instability due to neurofibromatosis: case report.

Abstract: Neurofibromatosis is an autosomal dominant genetic disease, characterized by cafe au lait spots, neurofibromas and several bony anomalies. Deformities of the spine are the most frequent alterations. Involvement of the cervical spine has been studied less frequently. The case of a 16-year-old male patient affected by neurofibromatosis, with cervical pain without neurological symptoms is presented. X-rays, CT-scan and MRI demonstrated the presence of cervical kyphosis, occipitoaxial instability and atlantoaxial instability with subluxation. Posterior occipito-C2 fusion was performed with prior placement of a halo-vest. The outcome at four years was good with solid occipito axial fusion, moderate loss of cervical spine flexion and moderate-to-severe limitation of cervical spine rotation. The incidence and variety of alterations of the cervical spine in patients affected with neurofibromatosis is discussed, as well as the results obtained by the treatment.

Prevalence of self-reported health complaints among shoe workers of small workshop exposed to organic solvents in Hebron City, West Bank: a cross-sectional survey.

Abstract: The study was conducted to estimate the prevalences of neurological disorders and mucous membrane irritation complaints among workers of shoe workshops in Hebron City, in particular to measure the associations between the occurrence of symptoms indicating polyneuropathy among workers and exposure to organic solvents in the glueing tasks. A group of 103 male workers from 30 workshops, exposed to organic solvents for more than one year were recruited to the study during the years 1996-1997. A validated Swedish neuropsychiatric questionnaire which contained questions on neurological and mucous irritation symptoms was used. Prevalence ratios were used as an indicator for relative risk. The overall prevalence of painful tingling of limbs (used as indicator of polyneuropathy) was high among the workshop workers (40%) and was significantly associated with long term exposure to organic solvents in glueing tasks (PR 2.8: 95% CI 1.0-8.3). Moderate associations were seen in other tasks. Headache and mental irritability did not show any association with organic solvent exposure in the workshop tasks. Breathing difficulty showed a moderate non-significant association with long term exposure to organic solvents (72 months) in cleaning tasks (1.9,0.7-4.8), while sore eyes also showed a moderate non-significant association with exposure to organic solvents for 25-72 months in the glueing tasks. Long term exposure to n-hexane (mainly found in the glues) could be the main cause of polyneuropathy among the workers of Hebron shoe workshops. The absence of effective ventilation systems and personal protective equipment might increase the prevalence of polyneuropathy among these workers. In conclusion, glues containing high concentrations of n-hexane are still in use in many shoe workshops in Hebron City (as well as in other developing countries), and long term exposure to n-hexane in glueing compounds could result in polyneuropathy among the workers. However, in the absence of objective measurements our results must be interpreted with caution. Well planned longitudinal studies with objective measures of exposure and disease are important for future research in developing countries.