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J Pujol

Publications and source records attributed to J Pujol.

At least 19 recordsLinked to original sources
PubMed1998

The effect of repetitive magnetic stimulation on localized musculoskeletal pain.

Current magnetic coil stimulators can efficiently activate neural structures without deep electrode placement and the local discomfort associated with transcutaneous electrical stimulation used in pain control. We tested the possibility of reducing pain in patients with localized musculoskeletal processes by applying repetitive magnetic stimulation on the tender body region. Thirty patients were randomized to receive 40 min of real or sham magnetic stimulation. After a single session, real magnetic stimulation significantly exceeded the sham effect: a 101-point pain score decreased by 59% in the treated group and 14% in sham-treated patients (z = -3.26, p = 0.001). The pain relief attained regularly persisted for several days. Results indicate that powerful magnetic coil stimulation can efficiently reduce pain originating from localized musculoskeletal injuries.

Adult↗
PubMed1998

Influence of amount and changes in axis of astigmatism on retinal image quality.

We measured retinal image quality in astigmatic eyes, using the double-pass technique. We analyzed the influence of the amount of astigmatism and changes in axis of astigmatism on the eye's optical performance. Different amounts of astigmatism were obtained by variation of the cylindrical power of a lens situated in front of the eye, between 0.25-diopter (D) overcorrection and 1-D undercorrection at intervals of 0.25 D. Changes in the axis of astigmatism were obtained by rotation of the lens, which neutralizes the astigmatism in an angle of +/- 10 degrees at 5 degrees intervals. The results show the decrease in retinal image quality and the increase in the degree of image astigmatism obtained when the amount of astigmatism increases or the angle between the lens and the eye axis is other than zero. In general, the largest variations correspond to when the astigmatism changes from 0 to 0.25 D or when the axis changes from 0 degree to +/- 5 degrees. The reduction in optical performance is smaller in living eyes than in an eye model or in an artificial eye. The aberrations present in the living eye reduce the relative loss of retinal image quality introduced by astigmatism.

Adult↗
PubMed1998

Clinical application of functional magnetic resonance imaging in presurgical identification of the central sulcus.

OBJECT: The authors sought to evaluate the advantages and limitations of functional magnetic resonance (fMR) imaging when it was used regularly in the clinical context to identify the central sulcus. METHODS: A 1.5-tesla MR system comprising a spoiled gradient recalled acquisition in the steady-state functional sequence and a cross-hand cancellation analysis method were used to evaluate 50 surgical candidates with centrally located space-occupying lesions in the brain. Three-dimensional (3-D) models of the patient's head and brain showing the relative position of the tumor and the eloquent cortex were obtained in each case. A selective and reproducible focal activation was found, indicating the probable central sulcus position in 41 patients (82%). Direct cortical stimulation confirmed the fMR findings in 100% of 22 intraoperatively assessed patients. Failure to identify the central sulcus occurred in 18% of cases and was mainly a consequence of intrinsic damage in the primary sensorimotor region that resulted in severe hand paresis. CONCLUSIONS: Although specific factors were identified that contributed to reduced sensitivity of fMR imaging in the clinical context, the present study supports functional assessment and 3-D representation of specific surgical situations as generally feasible in common practice.

Adolescent↗
PubMed1998

[The use of anorectal manometry and dynamic proctography in patients for diagnosis of solitary rectal ulcer syndrome].

BACKGROUND: Solitary rectal ulcer syndrome is caused by rectal prolapse and/or anismus. The diagnosis by physical examination, or using endoscopy or radiology alone is difficult. AIM: To evaluate the diagnostic utility of videoproctography and anorectal manometry in solitary rectal ulcer syndrome. PATIENTS AND METHODS: We studied six patients (5 women/1 man; 21-66 years) with rectal lesions suggestive of solitary rectal ulcer. By videoproctography, we measured the changes in the anorectal angle and the shape of the rectal wall during voiding. By manometry, we measured the resting pressure of the anal canal, and the pressure during maximal voluntary contraction and during straining. RESULTS: Proctography showed a rectal prolapse in 5 patients (non-exteriorized in 4). Both manometry and proctography demonstrated the normal relaxation of puborectalis and external sphincter during straining in 4 patients, manometry found sphincteric weakness in two of these patients. Both manometry and proctography evidenced anismus in a patient with rectal prolapse. CONCLUSION: The high prevalence of rectal prolapse in our patients allows us to recommend proctography in patients with morphological lesions suggestive of solitary rectal ulcer. The manometric examination identifies patients at risk of developing incontinence. Both techniques contribute to ascertain the presence of anismus and are indispensable in the selection of the adequate treatment for patients with solitary rectal ulcer.

Adult↗
PubMed1997

Magnetic resonance imaging measurement of the caudate nucleus in adolescents with attention-deficit hyperactivity disorder and its relationship with neuropsychological and behavioral measures.

OBJECTIVE: To investigate structural basal ganglia abnormalities in attention-deficit hyperactivity disorder (ADHD) and their relationship with the neuropsychological deficits and behavioral problems found in ADHD. DESIGN: Case-control study. SETTING: Adolescents were recruited from a local polytechnic institute of secondary education. SUBJECTS: Eleven adolescents with ADHD and 19 healthy control subjects. Subjects with ADHD were diagnosed by the school psychologist from a total population of 450 students according to the Diagnostic and Statistical Manual of Mental Disorders, Third Edition, Revised. Diagnosis was confirmed by the Conners Teachers Rating Scale and a structured family interview. MAIN OUTCOME MEASURES: Magnetic resonance imaging single-slice transversal measurements of the head of the caudate nucleus and a comprehensive neuropsychological evaluation, which was specially designed to assess frontal-striatal functioning. RESULTS: The ADHD group had a larger right caudate nucleus area than the control group. In control adolescents, larger caudate nucleus areas were associated with poorer performance on tests of attention and higher ratings on the Conners Teachers Rating Scale. CONCLUSIONS: These findings provide further evidence of the involvement of the caudate nucleus in the neuropsychological deficits and behavioral problems found in ADHD. The larger caudate nucleus found in the ADHD group could be related to a failure of the maturational processes that normally result in volume reduction.

Adolescent↗
PubMed1997

Periventricular white matter lucencies in patients with lacunar stroke. A marker of too high or too low blood pressure?

BACKGROUND: Periventricular white matter lucencies (PWML) have been described in stroke patients with arterial hypertension, hypotensive episodes, or increased nocturnal fall of blood pressure (BP). As a result of these mixed factors, the relationship between PWML and BP remains unsettled and the appropriate management of arterial BP in stroke patients with PWML is unknown. OBJECTIVE: To clarify the relationship between PWML, arterial BP, and cerebral hemodynamics. DESIGN: Cohort study followed up 6 months after index stroke. SETTING: Referral center. PATIENTS: In 41 consecutive patients with first-ever lacunar infarction, the extent of PWML detected on brain magnetic resonance images was measured. Six months after stroke, BP values were monitored during a 24-hour period and transcranial Doppler examinations were performed at rest and following the administration of acetazolamide. MAIN OUTCOME MEASURES: Correlation of cerebral hemodynamics and BP values with the extent of PWML. RESULTS: The severity of PWML varied substantially among patients, suggesting that PWML and lacunar infarctions could be due to several different mechanisms. Older age, elevated awake systolic BP, increased cerebrovascular tone, and the interaction between history of heart disease and the lowest heart rate were the strongest independent predictors of the severity of PWML. Diastolic BP and the vasodilatory capacity of the resistance vessels did not predict the severity of PWML. CONCLUSIONS: Overall, PWML are markers of systolic damage in older lacunar stroke patients with stiffer arteries. In addition, hemodynamic failure may be relevant in patients with concomitant heart disease.

Aged↗
PubMed1997

Impaired estimation of word occurrence frequency in frontal lobe patients.

Neuroanatomical correlates of the estimation of occurrence frequency have received little attention. This study investigates the possible role of the frontal lobe in estimating word occurrence frequency. A sample of 27 patients with frontal lesions were matched with normal controls by sex, age and years of education. Significant differences between patients and controls were found for frequency estimation, but not for item recognition. Studying accuracy of estimation as a function of actual frequency, the frontal group performed worse, especially at high frequencies of occurrence. As far as lesion lateralization is concerned, the right frontal subgroup performed worse than the control group in the estimation of frequency. Our results suggest that the prefrontal cortex plays a role in estimating word occurrence and that there is a dissociation between frequency memory and recognition memory, pointing to the involvement of two different cerebral systems.

Adult↗
PubMed1997

Lesions in the left arcuate fasciculus region and depressive symptoms in multiple sclerosis.

Depression is a common mood disturbance in multiple sclerosis (MS) patients. Epidemiologic data suggest a causative relationship between depressive symptoms and cerebral demyelination, although a specific lesion site responsible for depressed mood has not been identified. Given that depression in neurologic disease is closely related to frontal and temporal lobe damage, we focused our study on investigating the extent to which lesions in the white matter connecting both cerebral lobes may account for depressive symptoms in MS. Forty-five patients were assessed using the Beck Depression Inventory and an MRI protocol conceived to quantify lesions separately in the basal, medial, and lateral frontotemporal white matter. The presence of lesions in the left suprainsular white matter, the region that mainly includes the arcuate fasciculus, was specifically associated with depressive symptoms, accounting for a significant 17% of the depression score variance. Although a multifactorial origin is suspected for depression in MS, this finding gives support to the existence of a direct negative effect of demyelination on mood.

Adult↗
PubMed1997

[Neuropsychological deterioration in Huntington's disease].

INTRODUCTION: Huntington's disease (HD) is a neurodegenerative illness, autosomal dominantly inherited, that produces characteristic involuntary muscle movements (chorea) with cognitive abnormalities and personality. DEVELOPMENT: Neuropathological studies report premature cell death principally affecting the basal ganglia. The disease most commonly begins in the fourth or fifth decade of life, although in some cases, abnormalities have been documented in early childhood and as late as 50 years of age. Early cognitive deterioration in HD is not uniform, and patients with recently diagnosed HD may evidence selective deficits in learning and visuospatial/visuomotor ability, along with a relatively consistent pattern of impairment on subtests of the Wechsler Adult Intelligence Scale (WAIS). Neuroimaging reports of basal ganglia function have described striatal abnormality in HD and related with neuropsychological impairment. CONCLUSIONS: This paper provides the clinical-phenomenologic definition of the neuropsychological impairment and its associated features related with its neuropathological significance and to review the subject in the light of present day reports.

Aged↗
PubMed1997

Double-pass measurements of retinal image quality in monofocal contact lens wearers.

The double-pass method is applied to determine the optical image quality in monofocal contact lens (CL) wearers. This is an objective non-invasive technique that permits in vivo testing of the optical performance of CL wearers' eyes. Retinal image quality was measured for three subjects wearing two types of monofocal CLs: a rigid gas permeable (RGP) CL and a soft contact lens (SL), for pupil diameters of 3 mm and 5 mm. Results show the importance of ocular astigmatism regarding retinal image quality. In eyes presenting corneal astigmatism, the best results are obtained when wearing RGP CLs, because the lens compensates the corneal astigmatism. The modulation transfer function (MTF) is considerably smaller when no lens or soft lenses are worn, even for small amounts of astigmatism (0.5 D). When the astigmatism is corrected, the retinal image quality obtained with both types of CLs and with no lens is similar.

Astigmatism↗
PubMed1996

Neuropsychological alterations in patients with computed tomography-detected basal ganglia calcification.

OBJECTIVE: To investigate the cognitive and mental status of patients with basal ganglia calcification on a computed tomographic scan. DESIGN: Eighteen ambulatory patients with basal ganglia calcification and without other radiological findings who were identified from the computed tomography records of a general hospital in a 2-year period and 16 control subjects who were matched for age, education, sex, and premorbid IQ estimation consented to participate. All subjects underwent a neurological evaluation, a comprehensive neuropsychological battery, and tests with psychiatric rating scales. RESULTS: Significant differences for the control group were found in tests that evaluated motor speed and executive, visuospatial, and some memory functions. Four patients (22%) met criteria for organic mood disorder (minor depression, three patients; bipolar depression, one patient) according to the Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition, whereas six other patients (33%) met diagnostic criteria for obsessive-compulsive disorder. CONCLUSIONS: These results indicate that patients with basal ganglia calcifications frequently have a subcortical pattern of neuropsychological dysfunction and behavioral changes that are known to be associated with alterations of the frontal-limbic-basal ganglia circuits. The pattern of neuropsychological impairment is consistent with basal ganglia damage. However, poor performance in other neuropsychological tests suggest additional involvement of other connected networks.

Adult↗
PubMed1996

Are Himalayan Sherpas better protected against brain damage associated with extreme altitude climbs?

1. The potential risk of brain damage when low-landers attempt to climb the highest summits is a well-known fact. However, very little is known about what occurs to Himalayan natives, perfectly adapted to high altitude, when performing the same type of activity. 2. Taking into account their long-life climbing experience at extreme altitudes, we examined seven of the most recognized Sherpas with the aim of performing a comprehensive neurological evaluation based on medical history, physical examination and magnetic resonance brain imaging. We compared them with one group of 21 lowland elite climbers who had ascended to altitudes of over 8000 m, and another control group of 21 healthy individuals who had never been exposed to high altitude. 3. While all of the lowland climbers presented psychoneurological symptoms during or after the expeditions, and 13 of them (61%) showed magnetic resonance abnormalities (signs of mild cortical atrophy and/or periventricular high-intensity signal areas in the white matter), only one Sherpa (14%) showed similar changes in the scans, presenting neurological symptoms at extreme altitude. The neurological examination was normal in all three groups, and no neuroimaging abnormalities were detected in the control group. 4. The significant differences, in both clinical and neuroimaging terms, suggest that Sherpa highlanders have better brain protection when exposed to extreme altitude. Although the key to protection against cerebral hypoxia cannot be established, it is possible that an increase in the usually short period of acclimatization could minimize brain damage in those low-landers who attempt the highest summits without supplementary oxygen.

Adult↗
PubMed1996

Frontal lobe activation during word generation studied by functional MRI.

AIMS: To further delimit the specific verbal operations occurring in the dorsolateral frontal cortex during the generation of words. METHODS: Different verbal fluency tasks guided by distinct specifications (phonological, semantic, or automatic production of words) were used in a functional magnetic resonance study. The study group comprised 10 right-handed normal subjects ranging in age from 23 to 27 years. Functional magnetic resonance images were obtained in a 1.5-Tesla magnet using a spoiled GRASS sequence. RESULTS: Noticeable activation was found during the word generation tasks in the dorsolateral frontal cortex. The region showing the most prominent activation was the posterior part of the left middle frontal gyrus. Nevertheless, the different tasks each had a different activation effect. The phonologically guided generation of words produced the most consistent activation of the middle frontal gyrus, which mainly involved the premotor cortex. CONCLUSION: The results suggest that operations concerned with the generation of sound sequences, rather than the amount of produced words or their semantics, are responsible for sustained focal activity observed in the frontal lobes during verbal fluency tasks.

Adult↗
PubMed1996

Contribution of arterial blood pressure to the clinical expression of lacunar infarction.

BACKGROUND AND PURPOSE: The relation between symptomatic lacunar infarction, silent stroke, and arterial hypertension is controversial. METHODS: From 500 patients with ischemic or hemorrhagic stroke admitted to the Downtown Barcelona Stroke Registry between July 1992 and December 1994, we evaluated prospectively the prevalence of silent infarction in 249 patients who had a brain MRI. The association of risk factors with silent infarction was investigated with the use of logistic regression analysis. In a selected group of 43 patients with symptomatic lacunes, we performed at stroke follow-up transcranial Doppler sonography and 24-hour continuous blood pressure monitoring to evaluate whether blood pressure, cerebrovascular tone, and cerebral blood flow at rest and after the administration of 1 g acetazolamide correlated with silent infarction. RESULTS: A total of 147 silent infarctions were observed in 83 patients (33%). Most silent infarctions corresponded to small deep lesions in the territory of the lenticulostriate arteries. Patients with silent infarctions had higher systolic and diastolic blood pressure at stroke onset. However, on multivariate analysis, age greater than 60 years was the only risk factor associated with silent infarction. In a subgroup of 43 patients with symptomatic lacunes and patent extracranial vessels, systolic and diastolic pressure at stroke onset and diastolic pressure and vascular resistance at stroke follow-up were higher when silent infarctions co-existed. However, cerebral blood flow at rest and after acetazolamide injection were unrelated to silent infarction. CONCLUSIONS: Silent ischemia in patients with symptomatic lacunar and nonlacunar stroke was only associated with aging. However, a history of arterial hypertension was perhaps unrecognized, since hemodynamic testing and continuous blood pressure monitoring in patients with lacunar stroke suggested that the coexistence of silent lesions indicated a more generalized cerebral arteriolosclerosis.

Acetazolamide↗
PubMed1996

Neurospectroscopic alterations and globus pallidus hyperintensity as related magnetic resonance markers of reversible hepatic encephalopathy.

In patients with chronic hepatic encephalopathy, proton magnetic resonance spectroscopy can be used to detect specific metabolic abnormalities in the brain; MRI shows a hyperintense globus pallidus on T1-weighted sequences. We investigated the relationship between these two MR findings in a series of 25 patients with the use of quantitative data and a multiple regression analysis model. The cerebral increase in glutamine compounds and the decrease in myoinositol and choline correlated separately with globus pallidus hyperintensity, and each was complementary in accounting for this imaging finding. Such as association suggests that spectroscopic and imaging alterations are two different expressions of the reversible events that occur in the brain of patients with hepatic encephalopathy in that both disappear after liver transplantation. Globus pallidus hyperintensity seems to be a global indicator of the cerebral metabolic disorder, and the spectroscopic pattern denotes the specific metabolic alterations.

Aged↗
PubMed1996

Presurgical identification of the primary sensorimotor cortex by functional magnetic resonance imaging.

The ability of functional magnetic resonance (MR) imaging to detect a selective sensorimotor cortex activation in healthy subjects and the feasibility of motor activation in patients with lesions around the central sulcus were investigated. Twenty-five healthy volunteers performed 100 motor activation trials, using a variety of motor tasks, which were monitored by several image analysis methods. The functional images were obtained using a 1.5-tesla standard MR imaging system magnet with blood oxygenation level-dependent contrast. Four patients were assessed using functional MR imaging and invasive cortical mapping. Rolandic cortex activation was observed in 98% of the trials performed on healthy subjects in which no head motion occurred. Nevertheless, the cortical response was not selective in a task-rest analysis due to concurrent activation of neighboring regions. Across-task comparison analyses were useful in cancelling nonrelevant activity in most cases (86%). In the patient group, the region identified as the sensorimotor cortex by invasive means corresponded accurately to the area that was activated in functional MR imaging. Present data support the feasibility of detecting selective activation of the rolandic cortex, even in the clinical setting, leading the authors to suggest the usefulness of this widely available technique in surgical planning.

Adult↗