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Juan Sahuquillo

Publications and source records attributed to Juan Sahuquillo.

At least 19 recordsLinked to original sources
PubMed2006

Functional and magnetic resonance imaging correlates of corpus callosum in normal pressure hydrocephalus before and after shunting.

BACKGROUND: Normal pressure hydrocephalus (NPH) is associated with corpus callosum abnormalities. OBJECTIVES: To study the clinical and neuropsychological effect of callosal thinning in 18 patients with idiopathic NPH and to investigate the postsurgical callosal changes in 14 patients. METHODS: Global corpus callosum size and seven callosal subdivisions were measured. Neuropsychological assessment included an extensive battery assessing memory, psychomotor speed, visuospatial and frontal lobe functioning. RESULTS: After surgery, patients showed improvements in memory, visuospatial and frontal lobe functions, and psychomotor speed. Two frontal corpus callosum areas, the genu and the rostral body, were the regions most related to the clinical and neuropsychological dysfunction. After surgery, total corpus callosum and four of the seven subdivisions presented a significant increase in size, which was related to poorer neuropsychological and clinical outcome. CONCLUSION: The postsurgical corpus callosum increase might be the result of decompression, re-expansion and increase of interstitial fluid, although it may also be caused by differences in shape due to cerebral reorganisation.

Aged↗
PubMed2006

Neuroprotection in malignant MCA infarction.

Massive unilateral hemispheric infarction often develops progressive postischemic edema that leads to a malignant course of stroke with mortality of up to 80% with conventional medical therapies. Hypothermia and decompressive hemicraniectomy have shown neuroprotective effects in several animal models of focal transient and permanent MCA occlusion by reducing infarct size and improving neurological outcome. Our aim in this paper was to review the possible mechanisms of both therapies as well as the optimal time window and duration of application of each treatment in animal model and in human malignant MCA infarction reported in the literature.

Animals↗
PubMed2006

Differences in visual vs. verbal memory impairments as a result of focal temporal lobe damage in patients with traumatic brain injury.

PRIMARY OBJECTIVE: The aim of the present study was to determine whether the type of lesion in a sample of moderate and severe traumatic brain injury (TBI) was related to material-specific memory impairment. METHODS AND PROCEDURES: Fifty-nine patients with TBI were classified into three groups according to whether the site of the lesion was right temporal, left temporal or diffuse. Six-months post-injury, visual (Warrington's Facial Recognition Memory Test and Rey's Complex Figure Test) and verbal (Rey's Auditory Verbal Learning Test) memories were assessed. MAIN OUTCOME AND RESULTS: Visual memory deficits assessed by facial memory were associated with right temporal lobe lesion, whereas verbal memory performance assessed with a list of words was related to left temporal lobe lesion. The group with diffuse injury showed both verbal and visual memory impairment. CONCLUSIONS: These results suggest a material-specific memory impairment in moderate and severe TBI after focal temporal lesions and a non-specific memory impairment after diffuse damage.

Adolescent↗
PubMed2006

Percutaneous implantation of cerebral microdialysis catheters by twist-drill craniostomy in neurocritical patients: description of the technique and results of a feasibility study in 97 patients.

Cerebral microdialysis is increasingly used to monitor several types of neurocritical patients. This study presents the technique used in our unit for percutaneous implantation of cerebral microdialysis catheters using a small twist-drill craniostomy that can be performed in the intensive care unit (ICU). We also present the results of this technique in 89 head-injured patients and in eight patients with a malignant middle cerebral artery (MCA) infarction. One hundred and twenty-two cerebral microdialysis catheters were implanted in the 97 patients included in this study. One cerebral microdialysis catheter was implanted in the less damaged hemisphere of 67 head-injured patients with a diffuse brain injury. An additional microdialysis catheter was inserted in the pericontusional parenchyma of 22 patients with brain contusions. In five of the eight patients with a malignant MCA infarction, only one microdialysis probe was inserted in the penumbral zone. In the remaining three patients, two cerebral microdialysis catheters were implanted in the same hemisphere (one in the ischemic core and the other in the penumbra). Technical problems were detected in 18 (15%) of the 122 microdialysis catheters implanted and were more frequent during the initial period of using microdialysis in our unit. In four patients (3% of implanted catheters), follow-up computed tomography (CT) scans showed a small intracerebral blood collection (always <or=1 cc) around the microdialysis catheter. There were no microdialysis-related infections. In conclusion, percutaneous insertion of single or multiple microdialysis catheters in neurocritical patients by using twist drill craniostomy is feasible, fast, and safe.

Adolescent↗
PubMed2006

Influence of Angiotensin-converting enzyme polymorphism on neuropsychological subacute performance in moderate and severe traumatic brain injury.

Traumatic brain injury (TBI) frequently results in cerebrovascular lesions that may increase secondary damage and cause neuropsychological impairment. Previous studies suggest an association among the insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme (ACE), cardiovascular disease, and cognitive performance. Clinical and experimental studies have demonstrated the beneficial effects of ACE inhibitor treatment on vascular injury, hypertension, brain ischemia, and cognitive functioning. In a sample of 73 moderate and severe TBI patients, the authors assessed whether cognitive sequelae differed in relation to the ACE I/D polymorphism. D allele carrier patients performed worse than those with I/I polymorphism on tests involving attention and processing speed. Findings suggest that the physiopathological changes associated with TBI may have greater consequences in ACE D allele carriers.

Adolescent↗
PubMed2006

Posture-induced changes in intracranial pressure: a comparative study in patients with and without a cerebrospinal fluid block at the craniovertebral junction.

OBJECTIVE: The aim of this study was to determine posture-induced changes in intracranial pressure (ICP) when patients with hydrocephalus or idiopathic intracranial hypertension remained supine for 1 hour and then sat up and remained sitting for 3 hours. METHODS: Continuous ICP was monitored using a fiberoptic extradural sensor in: 1) 259 patients with hydrocephalus or idiopathic intracranial hypertension with free cerebrospinal fluid (CSF) flow through the craniovertebral junction and Sylvian aqueduct, 2) 20 patients with hydrocephalus secondary to aqueductal stenosis with free CSF flow through the craniovertebral junction, and 3) 97 patients with hydrocephalus associated with Chiari malformation. The maximum ICP difference (DeltaICP) was calculated as the difference between mean ICP in the supine position and minimum ICP value after changing body position. The mean ICP difference (DeltaICPmean) was calculated as the difference between the mean ICP in the supine position and the mean ICP while the patient was in a sitting position. RESULTS: In the complete sample, the median of DeltaICP was 13 mm Hg (interquartile range 10-17). The median of DeltaICPmean was 8 mm Hg (interquartile range 5-11). Both DeltaICP and DeltaICPmean were significantly greater in patients without obstruction in the craniospinal junction than in those with Chiari malformation (P = 0.005 and P = 0.014, respectively). No differences were found in DeltaICP or DeltaICPmean between patients with Sylvian aqueduct stenosis and those without (P = 0.777 and P = 0.346, respectively). CONCLUSION: ICP reduction after a change in body position is significantly greater in patients with free CSF flow through the craniospinal junction than in those with Chiari malformation, indicating the difficulty or impossibility of CSF displacement into the spinal canal in the latter.

Adult↗
PubMed2005

Corpus callosum functioning in patients with normal pressure hydrocephalus before and after surgery.

OBJECTIVES: Our aim was to evaluate corpus callosum functioning in a group of patients with normal pressure hydrocephalus (NPH) before and after shunting. METHODS: Left ear-extinction under a dichotic listening task was evaluated in twenty-three patients with NPH, 30 patients with Alzheimer's disease and 30 aged controls. RESULTS: Patients with NPH had higher levels of left ear extinction than the control and Alzheimer's groups. Sixty-one percent of NPH patients exhibited left ear suppression, compared with 13% of Alzheimer's patients and 17% of controls. Following surgery, NPH patients showed a significant change in the degree of asymmetry in the dichotic listening task. CONCLUSIONS: Hydrocephalus was associated with left-ear extinction,which diminished after surgery. Our results may indicate reversible functional damage in the corpus callosum.

Aged↗
PubMed2005

Hippocampal head atrophy after traumatic brain injury.

Traumatic brain injury (TBI) causes hippocampal damage. The hippocampus can be macroscopically divided into the head, body and tail, which differ in terms of their sensitivity to excitability and also in terms of their cortical connections. We investigated whether damage also varies according to the hippocampal area involved, and studied the relationship of hippocampal reductions with memory performance. Twenty TBI patients and matched controls were examined. MRI measurements were performed separately for the hippocampal head, body and tail. Memory outcome was measured by Rey's auditory verbal learning test, Rey's complex figure test and a modified version of Warrington's facial recognition memory test. Group comparison showed that patients had bilateral hippocampal atrophy, mainly involving the hippocampal head. Moreover, TBI subjects showed verbal memory deficits which presented slight correlations with left hippocampal head atrophy.

Adolescent↗
PubMed2005

Angiotensin I converting enzyme polymorphism effects in patients with normal pressure hydrocephalus syndrome before and after surgery.

Previous reports have suggested an association between the insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme (ACE), cardiovascular disease, and cognitive performance. Normal pressure hydrocephalus (NPH) is considered to be an example of reversible dementia although the clinical improvement after shunting varies from subject to subject. An association has been suggested between vascular risk factors and the development of NPH. The ACE plays a major role in vascular pathology and physiology. In the present study we investigated the distribution of an ACE gene insertion/deletion polymorphism in 112 patients diagnosed with NPH and in 124 controls. We also evaluated the role of this genetic polymorphism in cognitive functioning before and following surgery in a subgroup of 72 patients. No differences in genetic or allele distributions were found between patients and healthy subjects, but among patients, carriers of D/D or D/I genotypes obtained less cognitive benefit following shunt surgery, especially on measures of memory and frontal function. Our data support previous findings in other conditions indicating that possession of at least one D allele is associated with poorer cognitive performance.

Aged↗
PubMed2005

Ventricular enlargement after moderate or severe head injury: a frequent and neglected problem.

The primary goal of this study was to determine the incidence of post-traumatic ventriculomegaly (Evans' index > or = 0.30) in 95 head-injured patients with a Glasgow Coma Scale (GCS) score of < or =13 at admission. Additional objectives were to determine the relationship between an increase in ventricular size and several clinical and radiological features and outcome. A planimetric study was carried out in the sequential control computed tomography (CT) scans of 34 moderately head-injured (GCS 9-13) and 61 severely head-injured (GCS 3-8) patients with a minimum follow-up of 2 months. Between two and six CT scans were evaluated in each patient. The presence of subarachnoid hemorrhage (SAH) was registered. Evans' index was determined in all CT scans. In the final CT scan of each patient, ventricular size was related to the admission GCS score, age, the presence of SAH in the initial CT scans, type of brain lesion (classified according to the final diagnosis in the Traumatic Coma Data Bank classification), and outcome. Ventriculomegaly was found in 39.3% of patients with severe head injury and in 27.3% of those with a moderate head injury. Increased ventricular size was evident 4 weeks after injury in 57.6% and 2 months after injury in 69.7%. No relationship was found between post-traumatic ventriculomegaly and age, initial GCS score, the presence of SAH, or type of lesion (focal or diffuse). Post-traumatic ventriculomegaly was significantly correlated with outcome. Post-traumatic ventriculomegaly is a frequent and early finding in patients with moderate or severe traumatic brain injury.

Adolescent↗
PubMed2005

Short-term medical management of hydrocephalus.

Hydrocephalus is an excess accumulation of cerebrospinal fluid in or around the brain that can be produced by a broad spectrum of disorders. It can develop at any age and its incidence is increasing, both in infants and adults. Although the standard treatment of hydrocephalus is cerebrospinal fluid shunting, there are certain circumstances in which medical treatment, alone or in combination with shunting, has been suggested as an alternative. This review aims to present and discuss the indications for pharmacological treatment in the medical management of hydrocephalus, and the drugs most frequently used. Carbonic anhydrase inhibitors, loop diuretic agents, osmotic agents and fibrinolytic therapy are discussed. The most suitable drug seems to be acetazolamide, alone or in combination with furosemide. At present, osmotic agents are no longer used in the treatment of hydrocephalus. Fibrinolytic therapy administered directly into the ventricular system may not avoid the need for shunt placement, but may help in the management of hydrocephalus by preventing or reducing the rate of catheter obstruction and accelerating clot resolution.

Acetazolamide↗
PubMed2005

Good outcome in patients with normal-pressure hydrocephalus and factors indicating poor prognosis.

OBJECT: The authors set out to describe the outcome in a subgroup of patients with normal-pressure hydrocephalus (NPH) in whom prognostic factors were poor. This subgroup of patients who had received shunts was selected according to strict criteria. METHODS: From a cohort of 56 patients with NPH in whom shunts were placed, the authors selected a subgroup with four of the factors traditionally considered to indicate poor prognosis: idiopathic type, cortical atrophy, longstanding symptoms, and presence of dementia in addition to old age. Twelve patients met the inclusion criteria. After receiving shunts, 92% of the patients showed clinical improvement on the NPH scale; gait improved in 100% of patients, sphincter control in 90%, and dementia in 33%. Improvement was significant for gait and sphincter control, general NPH score, and most daily life activity scales. No significant differences regarding clinical, cognitive, or functional changes following surgery were found in comparison with the rest of patients (the good prognosis subgroup). CONCLUSIONS: The clinical condition of patients with NPH who present with traditionally accepted markers of poor prognosis can improve after surgery, especially as regards gait and sphincter control. The authors assert that the presence of these markers should not be considered to be an absolute criterion for ruling out shunt surgery in cases of NPH syndrome.

Age Factors↗
PubMed2004

Consensus meeting on microdialysis in neurointensive care.

BACKGROUND: Microdialysis is used in many European neurointensive care units to monitor brain chemistry in patients suffering subarachnoid hemorrhage (SAH) or traumatic brain injury (TBI). DISCUSSION: We present a consensus agreement achieved at a meeting in Stockholm by a group of experienced users of microdialysis in neurointensive care, defining the use of microdialysis, placement of catheters, unreliable values, chemical markers, and clinical use in SAH and in TBI. CONCLUSIONS: As microdialysis is maturing into a clinically useful technique for early detection of cerebral ischemia and secondary brain damage, there is a need to following such definition regarding when and how to use microdialysis after SAH and TBI.

Brain Injuries↗
PubMed2004

Influence of extraneurological insults on ventricular enlargement and neuropsychological functioning after moderate and severe traumatic brain injury.

Extraneurological insults secondary to TBI such as hypotension or hypoxia have been associated with mortality and morbidity. The purpose of this study was to investigate the influence of systemic complications on both neuropsychological outcome and cerebral atrophy. Fifty-seven patients selected from 122 consecutive admissions were studied. Data on the type and severity of injury as well as other systemic insults were collected prior to and during the first 3 days of hospitalization. These data included the presence or absence of a hypoxic episode during the pre-hospital period, the presence and degree of hypoxia, hypercapnia, anemia, hypotension and intracranial hypertension, pupillary reactivity, Glasgow Coma Scale score and coma duration. From the last control CT scan image, performed 6 months post-injury, four different indexes of ventricular dilatation were calculated. Neuropsychological assessment at 6 months included tests of verbal and visual memory, visuoconstructive functions, fine motor speed, and frontal lobe functions. Our results showed that hypoxia and hypotension were related to neuropsychological outcome and long-term ventricular enlargement. Hypoxic episodes prior to hospitalization were related to third ventricle dilatation and to adverse neurological and cognitive outcomes, especially to attention, motor speed, mental flexibility, fluency and verbal memory impairments, suggesting fronto-striatal and hippocampal dysfunction. We conclude that the effect of extraneurological insults on brain structure and function may be as important as the severity of the primary injury.

Adolescent↗
PubMed2004

Prospective study of methodological issues in intracranial pressure monitoring in patients with hydrocephalus.

OBJECT: Continuous intracranial pressure (ICP) monitoring is performed in selected patients with hydrocephalus to determine whether shunt placement is required. The mean ICP is usually calculated from end-hour readings manually recorded by nurses. The aim of this study was to evaluate the accuracy of manual recordings by comparing nurses' end-hour ICP readings with those of an online computerized ICP monitoring system that records one ICP value per second. METHODS: Continuous ICP monitoring was performed using a fiberoptic extradural sensor in 115 patients with hydrocephalus of different origins. A notebook computer was connected to an ICP monitor and was programmed to register one ICP value per second. In all patients, mean ICP values were calculated from data recorded manually by nurses at the end of every hour and from data recorded by the computer within the preselected time period. The two methods were compared using correlation analysis and the Bland and Altman method. The median number of ICP values noted manually by the nurses in each patient was 17 (interquartile range 15-18 readings), and that recorded by the software was 61,200 (interquartile range 54,000-64,800 readings). The correlation coefficient of the mean ICP values recorded by both methods was r = 0.99 (p < 0.001). The Bland and Altman analysis revealed a mean difference of 0.3 +/- 1.26 mm Hg between the two methods and that they were equally valid with all mean ICP values. CONCLUSIONS: The recording of end-hour ICP values by nurses is an accurate method of calculating the mean ICP after prolonged ICP monitoring in patients with hydrocephalus.

Adolescent↗
PubMed2004

Is the placement of shunts in patients with idiopathic normal-pressure hydrocephalus worth the risk? Results of a study based on continuous monitoring of intracranial pressure.

OBJECT: Data from many studies have demonstrated that shunt insertion in patients with idiopathic normal-pressure hydrocephalus (NPH) is associated with high morbidity and a lack of significant improvement; however, the use of strict diagnostic and treatment protocols can improve the results of surgery in these patients. The primary aim in this prospective study was to analyze the results of shunt placement in 43 patients with idiopathic NPH. A secondary aim was to determine the relationship between several clinical and neuroimaging factors, and patient outcome after surgery. METHODS: Thirty men and 13 women with a mean age of 71.1 +/- 6.9 years participated in this study. All patients underwent clinical, neuropsychological, and radiological assessment before and 6 months after surgery. In all patients continuous monitoring of intracranial pressure was performed using a fiberoptic extradural sensor. In 31 patients cerebrospinal fluid dynamics were also determined. Eighty-six percent of patients showed clinical improvement after shunt insertion, 11.6% showed no change, and 2.3% exhibited some worsening. Gait improved in 81.4% of the patients, sphincter control in 69.8%, and cognitive dysfunction in 39.5%. There was no treatment-related death. Early or late postsurgical complications occurred in six patients (14%), although all of these complications were minor or were satisfactorily resolved. The complete clinical triad, cortical sulci size, and periventricular lucencies were related to outcome, whereas patient age, symptom duration, ventricular dilation, and the degree of presurgical dementia were unrelated to outcome. CONCLUSIONS: Given the correct diagnosis, shunt insertion can produce marked improvement in patients with idiopathic NPH syndrome, causing few deaths and few clinically relevant complications.

Aged↗
PubMed2004

Hypothermia.

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Brain Injuries↗