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R Khalil

Publications and source records attributed to R Khalil.

At least 19 recordsLinked to original sources
PubMed1999

[Divergent asymmetries of the temporo-parietal cortical areas: anatomo-functional correlations and evolutionary and developmental implications].

Human brains present a clear asymmetry of the postero-lateral cortical area, so called "planum temporale" (Geschwind and Levitsky). This asymmetry is on favour of the left brain. A similar asymmetry is observed on the parietal operculum. MRI studies of 37 healthy volunteers have shown a clear difference between individuals. Mixing the index of temporal and parietal asymmetry, the authors consider four types: the most frequent pattern concerns 90% of right handed. For the others, 10% there are left handed as right handed. On conclusion, planum as many asymmetry and opercular asymmetry can be divergent, and both canan to determines handedness.

Adolescent↗
PubMed1998

Drug-related hospitalization at a tertiary teaching center in Lebanon: incidence, associations, and relation to self-medicating behavior.

OBJECTIVE: In Lebanon there is very limited restriction on drug use. Accordingly, self-medication is highly prevalent. This study examined the influence of these factors on the development of drug-related illnesses that lead to hospitalization. METHODS: Patients admitted to the medical and pediatric wards of a tertiary teaching center in Beirut, Lebanon, over a period of 6 months were interviewed and their charts were reviewed. Admissions attributable to adverse drug reactions or therapeutic failures were identified and characterized with respect to demographic factors, medical history, drug intake, and self-medicating behavior. The influence of these variables on the development of drug-related illnesses was examined by logistic regression. RESULTS: Of 1745 adults and 457 children, there were 177 (10.2%) and 36 (7.9%) drug-related illnesses, respectively. Adverse drug reactions accounted for 7.0% and 5.7% and therapeutic failures for 3.2% and 2.2% of adult and pediatric admissions, respectively. Self-medication was commonly practiced (52.6% of adults and 41.6% of children). Logistic regression analysis revealed that female sex increased the risk of adverse drug reaction in adults, whereas self-medication decreased the risk. In children, the risk of adverse drug reaction was increased in lower socioeconomic groups, whereas the risk of therapeutic failure was increased by a positive history of atopy or drug reaction. CONCLUSIONS: These results provide the first detailed analysis of the problem of drug-related illnesses in a developing country and identify a number of related or risk factors. Despite the lack of regulation of drug dispensing and the unchecked access to drugs in Lebanon, the incidence of drug-related illnesses is not different from that in Western nations. This finding may have relevance to policies of drug regulation in other countries.

Adolescent↗
PubMed1998

Case report of ruptured endometriotic cyst in pregnancy treated by laparoscopic ovarian cystectomy.

Pregnancy is thought to have an ameliorating effect on endometriosis, inducing a state of quiescence. We report a case of ruptured endometriotic cyst in pregnancy successfully treated by laparoscopic ovarian cystectomy. Our patient subsequently progressed uneventfully to deliver a healthy baby girl at term. Laparoscopic ovarian cystectomy in pregnancy, even with ruptured cysts, appeared to be safe in trained hands with similar benefits of reduced post-operative morbidity.

Adult↗
PubMed1997

[Acute myelopathies in young patients and multiple sclerosis. prospective study of 20 cases].

The risk of progression to multiple sclerosis (MS) after an episode of acute non compressive episode involving the spinal cord remains uncertain. A follow-up study was performed to determine the risk of early progression to MS in 20 patients presenting with clinically isolated lesions of the spinal cord, combined clinical evaluation, spinal and brain magnetic resonance imaging (MRI), visual, brainstem auditory and somatosensory evoked potentials (VEPs, BAEPs, SEPs), and cerebrospinal fluid (CSF) electrophoresis analysis. Spinal cord MRI demonstrated more lesions in cervical region (74 p. 100) than thoracic or lumbar regions (26 p. 100). Six patients (30 p. 100) had an initial brain MRI that was strongly suggestive of MS and 5 patients (25 p. 100) had only one MS-like abnormality. Eight patients (40 p. 100) had abnormal VEPs, 3 (15 p. 100) abnormal BAEPSs and only 44 p. 100 (8/18) abnormal SEPs. In contrast, CSF analysis showed oligoclonal bands (CSFOB) in 15/19 patients (79 p. 100). The diagnosis of MS was performed initially in 13 cases (65 p. 100) (clinically definite MS (CDMS) in 30 p. 100, laboratory-supported definite MS (LSDMS) in 61 p. 100 and clinically probable (CPMS) in one case). During the follow-up period (18 +/- 7 months), 8 patients (40 p. 100) presented one or more exacerbations and time to the first recurrence was 8 +/- 5 months. Seven of these 8 patients were initially treated by infusion of methylprednisolone. Among these patients, all of them had CSF OB and initial brain MRI was strongly suggestive of MS in 3 of them. During this follow-up period, brain MRI showed emergence of lesions in 4 cases with normal initial examination and 3 of them presented exacerbations. At the follow-up term, the diagnosis of MS was performed in 15 cases (75 p. 100) CDMs in 66 p. 100, LSDMS in 26 p. 100 and CPMS in one case). This confirms the predictive value of brain MRI and CSF OB for the diagnosis of MS in patients who present with clinically isolated acute syndrome of the spinal cord.

Acute Disease↗
PubMed1996

[Reflex epilepsy with seizures induced by mental calculation, playing chess and scrabble].

Reflex seizures induced by higher mental activity is rare. We report the case of a young man with myoclonic jerks and generalized tonico-clonic convulsion precipitated by calculation, playing chess and scrabble. Routine EEG, including hyperventilation and photic stimulation, showed no abnormality. Tests stimulation procedures, including spatial tasks, induced focal and generalized EEG spike-wave complex and myoclonic jerks. Valproate was effective in reducing epileptic seizures during a follow-up period of three years. Comparison of our case with previously reported reflex epilepsy with seizures induced by higher mental activity is discussed.

Adult↗
PubMed1995

Diverging asymmetries of temporo-parietal cortical areas: a reappraisal of Geschwind/Galaburda theory.

The general theory on the biological foundations of cerebral dominance formulated in 1985 by Geschwind and Galaburda entirely relies on a postulated causal relationship between anatomical asymmetry of the planum temporale and functional lateralization of the human brain, but does not take into account asymmetry of another cortical region, the parietal operculum. In 40 normal volunteers whose handedness was specified by the Edinburgh Handedness Inventory, we assessed asymmetries of these two regions on MRI sagittal scans. For both measurements, a significantly larger leftward asymmetry was found in the 24 consistent right-handers compared to the 16 non-right-handers. Moreover, the combination, for each subject, of the two indices of asymmetry, yielded four different subtypes between which handedness distribution significantly differed. We conclude that planum temporale and parietal operculum asymmetries may be divergent and that their convergence is strongly associated with right-handedness. Functional and developmental implications of these findings are discussed by reference to the Geschwind/Galaburda theory.

Adolescent↗
PubMed1995

Mutism and auditory agnosia due to bilateral insular damage--role of the insula in human communication.

We report a case of transient mutism and persistent auditory agnosia due to two successive ischemic infarcts mainly involving the insular cortex on both hemispheres. During the 'mutic' period, which lasted about 1 month, the patient did not respond to any auditory stimuli and made no effort to communicate. On follow-up examinations, language competences had re-appeared almost intact, but a massive auditory agnosia for non-verbal sounds was observed. From close inspection of lesion site, as determined with brain resonance imaging, and from a study of auditory evoked potentials, it is concluded that bilateral insular damage was crucial to both expressive and receptive components of the syndrome. The role of the insula in verbal and non-verbal communication is discussed in the light of anatomical descriptions of the pattern of connectivity of the insular cortex.

Adult↗
PubMed1995

Circulating immune complexes in various forms of Behçet's disease.

BACKGROUND: The etiology of Behçet's disease (BD) is uncertain but there is strong evidence that the immune system is implicated in its pathogenesis. METHODS: We assessed circulating immune complexes (CIC) in peripheral blood of 34 patients with BD, forming eight clinical groups, using a laser nephelometer to obtain more insight in the pathogenesis of different clinical forms of BD. Twenty healthy controls and eight patients with recurrent oral ulcerations were also included in the study. RESULTS: Levels of CIC were significantly higher in patients (1.83 +/- 0.93 microgram/mL) than in controls (0.84 +/- 0.51 microgram/mL; P < 0.001). High titers were found in the groups of patients with erythema nodosum (3.14 +/- 0.44 microgram/mL), neurologic manifestations (2.9 +/- 0.58 microgram/mL), and ocular manifestations (2.34 +/- 0.93 microgram/mL). Compared to patients with recurrent oral ulcerations (1.91 +/- 0.77 microgram/mL), the mean value of CIC in patients with BD did not differ significantly, but the groups of patients having erythema nodosum, positive pathergy, and neurologic manifestations had significantly higher levels (P < 0.05) and the group of patients at the mild end of the spectrum (group 8) had a significantly lower level (1.09 +/- 0.41 microgram/mL) (P < 0.05). Only the groups having erythema nodosum, positive pathergy, and neurologic manifestations had significantly higher levels of CIC when compared to other groups lacking these clinical features, whereas group 8 had a significantly lower level (P < 0.05) when compared to all other groups. CONCLUSION: Our results show that CIC may be involved in the pathogenesis of BD, especially in those clinical forms of the disease with erythema nodosum, neurologic manifestations, and ocular manifestations. Patients at the mild end of the BD spectrum do not show significant changes in CIC levels compared to healthy control subjects. We can, therefore, suggest that in BD CIC may be implicated more in the pathogenesis of some features than of others.

Adolescent↗
PubMed1995

[Pseudovascular laterobulbar syndrome secondary to astrocytoma].

A patient presented with an atypical left lateral medullary syndrome (LMS) mimicking a stroke. Magnetic resonance imaging demonstrated a tumour in the left dorsolateral part of the medulla. Biopsy revealed a grade II astrocytoma. The patient died two weeks after surgery. Nine pathologically verified previous cases of LMS caused by a tumour are reviewed. LMS is invariably atypical because of associated supratentorial or extensive brainstem symptomatology. Onset is usually progressive but stroke-like onset has been occasionally reported. Glial tumours as a cause of LMS are less frequent than metastasis. Successful treatment has been reported in a case of low grade astrocytoma.

Astrocytoma↗
PubMed1995

[Characterization of gestural disorders in primary progressive apraxia: diagnostic and nosographic contribution].

Five cases are reported of patients with so-called primary progressive apraxia, defined as a slowly worsening disturbance of gestural abilities, without other major cognitive changes during a long period, in relation to degenerative cortical atrophy. All five cases, as other cases in the literature, share the following common features: 1) asymmetrical onset of upper limb clumsiness, more often involving the left side, later involving the contralateral side and lower limbs; 2) after a variable delay, the occurrence of symptoms suggesting subcortical involvement (akinesia, limb stiffness, various kinds of movement disorders, dystonia, paresis of vertical gaze); 3) diffuse cortical atrophy typically more pronounced in the superior parietal cortex opposite to the first side affected. The unusual nature of apraxia in all these cases is pointed out and referred to as Luria's "kinesthaesic apraxia", ascribed to a loss of "selectivity" of distal elementary movements. This pattern of symptoms and their specific outcome could represent a distinct entity.

Aged↗
PubMed1995

[Lateral bulbar infarctions. Distribution, etiology and prognosis in 40 cases diagnosed by MRI].

Recent advances in lateral medullary syndrome have focused on otoneuro-ophthalmology and magnetic resonance imaging (MRI). To reevaluate lateral medullary infarcts, 40 non fatal cases (30 men and 10 women, mean age 57.5 years) accounting for 4.5 p. 100 of overall cerebral infarcts were consecutively included in a prospective study using MRI in all cases. Thirty three patients were investigated using transfemoral or magnetic resonance angiography. Besides classical symptomatology, visual disorders were usually noted: diplopia (n = 18), transient visual tilt of the surrounding (n = 4), skew deviation (= 4), esotropia (n = 2) or conjugate gaze deviation (n = 2). The middle part of the medulla was affected in 35 cases. When associated, ipsilateral peripheral facial palsy and/or deafness were linked to the involvement of the pontomedullary junction (n = 3) while ipsilateral hemiparesis (Opalski's syndrome, n = 4) was linked to the involvement of the lower medulla and the cervicomedullary junction. MRI showed an associated cerebellar infarct in 35 p. 100 of cases. Of 33 patients angiographically investigated, 27 (82 p. 100) had stenosis or occlusion of the ipsilateral vertebral artery, usually affecting the intracranial portion, when 3 had isolated posterior inferior cerebellar artery occlusion. Atherosclerosis was recognized as the main cause of lateral medullary infarcts (n = 25). Other miscellaneous etiologies were diagnosed: coagulopathy (n = 2), spontaneous arterial dissection (n = 2), dolichoectatic artery (n = 1), arteriolopathy (n = 1) or cardiogenic embolism (n = 1). At the term of follow-up (mean: 35 +/- 24 months), 33 patients were free of residual handicap, 8 had experienced recurrent vertebrobasilar infarcts, including 3 medullary infarcts (median ipsilateral, n = 1 or lateral contralateral, n = 2), and 3 were died of basilar artery thrombosis complicating extensive atherosclerosis of the intracranial vertebrobasilar system.

Adult↗
PubMed1994

[Cerebral infarction in patients aged 16 to 35 years. Prospective study of 52 cases].

OBJECTIVES: Aetiologies of cerebral ischemic events in young adults are various and often contraversial: atherosclerosis plays a role after age 35 years, cardioembolism is often recognized as the major cause, and numerous new predisposing conditions have been described. To evaluate very premature cerebral infarction, we studied prospectively 52 consecutive patients (34 women and 18 men) aged 16-35 years (mean 28.6 +/- 5.6 years) admitted over a 6-year period for an arterial cerebral infarct identified on CT, on MRI or both. METHODS: All patients were investigated using a standard protocol including cerebral angiography, transthoracic echocardiography, 24-hour Holter ECG monitoring, coagulation inhibitors levels, lupus anticoagulant testing, HIV and syphilitic serologies. Additional investigations were performed in a majority of patients: transesophageal echocardiography in 33, contrast echocardiography in 50, and anticardiolipin antibodies levels in 38. RESULTS: The arterial distribution of infarction did not differ from that of overall stroke patients. Sixteen cases were classified as certain aetiologies, including cardiac diseases with high embolic risk (n = 9), spontaneous arterial dissection (n = 4), moya-moya disease (n = 1), atherosclerosis (n = 1), and inherited antithrombine III deficiency (n = 1). Eighteen cases were classified as possible aetiologies including cardiac diseases with low embolic risk (n = 11) such as mitral valve prolapse or atrial septal aneurysm, miscellaneaous arteriopathies (n = 3) such as arterial dysplasia, antiphospholipid antibodies syndrome (n = 1) and migrainous stroke (n = 3). The 18 last cases were classified as unknown aetiologies, despite all patients but one had at least one vascular risk factor: this group significantly differed from the formers in that the patients were more frequently women using oral contraceptive associated with tobacco consumption, hypercholesterolemia, or both. Two patients died acutely and the survivors were followed 31 +/- 18 months. Three patients experienced recurrent stroke. Functional outcome was assessed using the Rankin scale on admission and 6 to 12 months after the onset of stroke: patients evaluated < or = 2 (no to mild handicap) were 31% on admission and 82% after recovery. Twenty six p. cent remained unable to resume a work. CONCLUSION: Despite extensive evaluation, identification and classification of aetiologies of cerebral infarction in young adults should be cautious because the risk as well as the pathogenesis of many potential causes still need to be defined.

Adolescent↗
PubMed1994

[Spinal dural fistula with peri-medullar venous drainage].

Clinical and neuroradiological findings of 8 patients with a spinal dural arteriovenous fistula are reviewed. Disturbance of micturition or defecation and weakness of the legs were always present and the most frequent initial symptom was a progressive spastic paraparesis. Duration of symptoms before diagnosis was 2 years. Lumbar puncture showed elevation of proteins and myelography demonstrated dilated perimedullar posterior veins. In every case, magnetic resonance imaging of the spinal cord (T2- weighted images) revealed intramedullary high signal intensity of the conus medullaris and selective angiography confirmed the site of the dural fistula. Each patient was treated with endovascular method consisting in liquid adhesive embolization (0.2 cc of N-butyl cyanoacrylate) with hyperselective catheterism of the dorsospinal artery. Embolization procedure was successful in 6 cases with large improvement of leg weakness and partial regression of disturbed micturition and defecation. The pathophysiological mechanisms explaining the clinical signs are discussed.

Aged↗
PubMed1994

[Quantitative approach of postural asynergia in cerebellar diseases].

In his original description of cerebellar asynergia, Babinski, in 1899, presented a patient with cerebellar dysfunction performing a backward upper trunk bending. When the patient tried to bend his head and trunk, his lower limbs stayed almost motionless, because the associated flexion of the knee and hip, usually observed in a normal subject, did not take place. To reassess the possibility that asynergia may actually be a symptom of cerebellar dysfunction, a combined kinematic and electromyographic (EMG) analysis of the upper-trunk bending was performed on 3 patients suffering from progressive cerebellar ataxia of late onset and showing a significant atrophy of the vermis on MRI examination. Compared with 3 age and sex-matched control subjects, a significant slowing down of the upper-trunk displacement and a marked reduction of the associated displacement of hip and knee was observed. EMG recordings of three pairs of antagonistic muscles at trunk level (rectus abdominis, erectores spinae), at thigh level (vastus lateralis, semi membranosus), and at leg level (tibialis anterior, gastrocnemius lateralis), showed that the reciprocal activation pattern characteristic of a normal fast movement was absent at the thigh level in the cerebellar patients. This lack of reciprocal activation of the thigh muscles during the upper-trunk bending might explain the reduction of the compensatory displacement of the hip and knee. It might also represent an essential feature of cerebellar dysfunction in provoking axial asynergia between the upper-trunk, which is the moving segment, and the leg, which is the supporting segment during equilibrium control and during whole body displacement.

Adult↗
PubMed1994

[Familial deficiency of C7 associated with adrenomyeloneuropathy].

A 24-year old man presented with recurrent meningitis resulting from familial deficiency of a late component of the complement system (C7). Five years later, he developed gait disturbance, mental impairment and loss of hearing. Adrenomyeloneuropathy was diagnosed by a raised plasma long chain fatty acids level.

Adrenoleukodystrophy↗
PubMed1994

[A study of 82 cerebral infarctions in the area of posterior cerebral arteries].

Of 598 consecutive non-selected cases of cerebral infarction included in a stroke registry, 82 cases (54 men and 28 women, mean age 66 +/- 14 years) of spontaneous and isolated posterior cerebral artery (PCA) territory infarction (right PCA in 36, left PCA in 35 and both in 11) were identified on the basis of CT combined with MRI in 51 cases. Infarction was superficial in 25 (group A), combined deep-superficial in 23 (group B) and deep in 34 (group C). Of 48 superficial lesions, 29 were massive while 19 were restricted to the territory of one branch. Of 57 deep lesions, 21 were located in the inferolateral thalamic territory, 10 in the paramedian thalamic territory, 12 in other midbrain or thalamic territories, and 14 in a combination of various midbrain and/or thalamic territories. Of 41 patients with unilateral superficial involvement, 39 had homonymous visual field defect. Unawareness of the visual defect and visual release hallucinations were observed with the same frequency in right and left lesions. Of 7 patients with bilateral superficial involvement, only 5 had bilateral visual field defect including incomplete cortical blindness in 3. The frequency of confusional state (n = 24) did not differ significantly in left versus right sided lesions while it was significantly higher in superficial or combined versus deep lesions (p = 0.05). Of 18 clinically evaluable patients with left PCA territory infarct, 14 had speech disorders including pure alexia in only one case. Of 15 patients with right territory infarction, 10 had spatial judgement disorders.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗