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D Santamarta

Publications and source records attributed to D Santamarta.

16 recordsLinked to original sources
PubMed2005

Evolution of intracranial pressure during the immediate postoperative period after endoscopic third ventriculostomy.

OBJECTIVE: To establish a more accurate indication for endoscopic third ventriculostomy (ETV) in patients with noncommunicating hydrocephalus through the analysis of the evolution of postoperative mean intracranial pressure (ICPM). METHOD: Intracranial pressure (ICP) was recorded overnight during 8-hour periods with an intraventricular probe. A personal computer connected to the ICP monitor minutely recorded the values of ICP. Twenty-four patients were monitored from day 1 to day 3 after ETV. The evolution of ICPM was analysed with an ANOVA test for repeated measures. The relevance of different factors (age, etiology, size of the lesion leading to hydrocephalus, clinical course and outcome) on the evolution of ICPM was explored with a two-factor ANOVA. RESULTS: ICPM progressively decreased from day 1 to day 3 after ETV (p = 0.03). ICPM on the first postoperative day was 15.81 +/- 2.04 mm Hg (mean +/- standard error) and 13.43 +/- 1.44 mm Hg on the third postoperative day. Different patterns in the evolution of ICPM have been detected according to the age of the patient and the clinical course of hydrocephalus. CONCLUSION: ICPM progressively decreases after ETV. This pattern is not constant. It has been clearly detected in children and in acute forms of hydrocephalus.

Adolescent↗
PubMed2005

Outcome of endoscopic third ventriculostomy. Results from an unselected series with noncommunicating hydrocephalus.

BACKGROUND: Endoscopic third ventriculostomy (ETV) has gained acceptance as the treatment of choice for noncommunicating hydrocephalus despite a relatively high failure rate and a higher surgical risk than the placement of a shunt. The benefits of shunt independence overcome both drawbacks. This argument also serves to consider candidates for ETV patients with a poor chance of success, a fact which may to a certain degree explain failure rates higher than 20% in most unselected series of patients with noncommunicating hydrocephalus. METHOD: From 1997 to 2003 sixty-six patients with suspected noncommunicating hydrocephalus were treated with ETV. Male and female patients were equally distributed. It is an adult-based series (median age 53 years). The etiology of hydrocephalus was a space-occupying lesion in 39 patients (59%) and primary aqueductal stenosis in 27 (41%). Forty-seven patients presented an acute form of hydrocephalus (71%), the remainder presented a chronic form of hydrocephalus. The morbidity and outcome of the procedure were reviewed. Criteria for success was shunt independence and failure was considered when any surgical manoeuvre was further required for the treatment of hydrocephalus. The outcome was evaluated using the Kaplan-Meier survival method. FINDINGS: The probability of remaining with a functioning ETV at 5.7 years (mean follow-up period) is 71.6% (95% confidence interval: 60.5-82.8). Failure occurred in 18 patients (27.3%). If failure occurs, there is a cumulative probability of 90% (95% confidence interval: 84-97) that the failure declares itself during the first 16 days after surgery. There were transient complications in five patients (7.5%), permanent in one (1.5%) and no mortality related to the procedure. CONCLUSIONS: ETV had a 5-year success rate of 71.6% with a low rate of permanent complications. When ETV is successful, the result tends to hold up over time. Delayed failure is a rare event.

Adult↗
PubMed2005

[Skull base meningiomas: a predictive system to know the extent of their surgical resection and patient outcome].

OBJECTIVE: The aim of this study was to build a preoperative predictive system which could provide reliable information about: 1 degrees which skull base meningiomas can be total or partially removed, and 2 degrees their surgical outcome. METHOD: Patient histories and imaging data were reviewed retrospectively from 85 consecutive skull base meningiomas patients who underwent surgery from 1990 and 2002. From the preoperative data, nine variables were selected for conventional statistical analysis as regards their relationship with: 1 degrees total vs partial tumor resection and 2 degrees with patients outcome according to the degree of tumour removal. RESULTS: From the nine variables analysed only two had a statistical association with the type of tumour resection performed (total vs partial) and the patient outcome: 1) arteries encasement and 2) cranial nerves involvement. Upon correlating these two variables with the type of tumour resection performed (total vs partial) and with the Karnofsky'scale to evaluate patients surgical outcome, the following grading groups were identified: Grade I: skull base meningiomas which did not involve cranial nerves or artery or only encased one artery or one cranial nerve. In these cases the incidence of gross tumour resection was 98.3% (p< 0.0001) and the perspective to reach 70 points in the Karnofsky'scale was of 96.5% ( p=0.001). Grade II: skull base meningiomas which involved one cranial nerve and encased, at least, two main cerebral arteries. In these cases, the frequency of total resection, decreased to 83.3% (p<0.0001) and the probability to reach 70 points in the Karnofsky'scale was 70.6% (p=0.001). Grade III: skull base meningiomas which involved two or more cranial nerves and encased several arteries In this group, the frequency of a total resection was of 42.9% (p<0.0001) and the probability of reaching 70 points in the Karnofsky'scale was only 60% (p=0.001). CONCLUSIONS: We propose a preoperative grading system for skull base meningiomas that helps predicting both whether total or partial tumor removal will be achieved during surgery and the immediate postsurgical outcome of the patient. In applying this predictive system we will be able to reduce surgical morbidity, to advance the possibility of a radiosurgical treatment and give a more precise information to the patients and their families about our surgical decision-making process.

Adolescent↗
PubMed2004

[Endoscopic third ventriculostomy: risk factors for failure and evolution of ventricular size].

INTRODUCTION: Endoscopic third ventriculostomy is the treatment of choice for non communicating hydrocephalus at our institution. Several factors have been associated with failure of endoscopic third ventriculostomy. The goals of the study have been to evaluate the outcome, the influence of factors theoretically prone to failure of ventriculostomy and the evolution of ventricular size. MATERIAL AND METHODS: Fifty-six patients (mean age 48.5 yrs) treated with an endoscopic third ventriculostomy during the period 1997-2002 were analysed retrospectively. Hydrocephalus was classified as acute (68%) and chronic forms. Etiology was classified in space-occupying lesions (59%), primary aqueductal stenosis (34%) and Chiari malformation (7%). The presence of the following factors theoretically prone to failure was considered: age below one year, history of mielomeningocele, cerebrospinal fluid (CSF) infection, intracranial haemorrhage, radiotherapy, craniotomy and previous treatment of hydrocephalus with a shunt. Ventricular size was measured linearly with four ventricular index pre- and postoperatively. RESULTS: The global success rate was 71.4% (mean follow-up 26 months). Endoscopic third ventriculostomy for hydrocephalus secondary to cerebral metastases obstructing CSF pathways was associated with a higher risk of failure (p=0.006). None of the risk factors considered was associated with a higher risk of failure. The evolution of the ventricular size measured with linear methods is associated with outcome. Evans ratio, third ventricle index, cella media index and ventricular score decreased in patients whose outcome is satisfactory and increased in those cases deemed clinical failures (p< 0.05). CONCLUSION: The risk of failure increases in patients with cerebral metastases close to CSF pathways, likely due to the concurrence of mechanisms other than obstruction. Changes in ventricular size are associated with outcome.

Adolescent↗
PubMed2003

[Analysis of cerebrospinal fluid related complications (hydrocephalus, fistula, pseudomeningocele and infection) following surgery for posterior fossa tumors].

INTRODUCTION: Hydrocephalus, cerebrospinal fluid (CSF) leak, pseudomeningocele and CSF infection are potential complications related to surgical treatment of posterior fossa tumors. The objectives of this study were to review the incidence of such complications and to identify contributing factors related to them. MATERIAL AND METHODS: This study is based on a retrospective review of the medical records of 71 consecutive patients who underwent posterior fossa surgery for a tumor between the period January 1997 and December 2001. Postoperative hydrocephalus was defined as enlargement of the ventricles and the subsequent clinical worsening requiring surgical treatment. Criteria for CSF leakage were:observed leak of CSF through the wound, rhinorrhea or otorrhea. Pseudomeningocele was determined when there was a large epidural CSF collection diagnosed in the postoperative period or by magnetic resonance imaging performed at least three months after posterior fossa surgery. Finally, CSF infection was defined on clinical ground and positive biochemical examination, but not necessarily positive cultures. RESULTS: The series included 84 operations for resection of posterior fossa tumors on 71 patients. There were CSF related complications in 31% (26/84)with the following detailed incidence: 9.5% (8/84) postoperative hydrocephalus; 14.3% (12/84) CSF leak, 7.1% (6/84) pseudomeningocele; 8.3% (7/84) CSF infection. The mortality rate is 5.9% (5/84). The tumor size was the only statistically significant factor associated with the occurrence of CSF related complications (mean 39.43 mm, SD 18.51 mm vs.29.80 mm, SD 14.12 mm, p=0.015). In the subgroup of patients, in which hydrocephalus was managed preoperatively, the election of an external ventricular drain vs.other strategies (subcutaneous reservoir, definite shunt or endoscopic third ventriculostomy) was associated with a higher occurrence of CSF related complications (p=0.006). The mortality rate was associated with age (mean 63.60 years, SD 5.86 years vs.49.18 years, SD 16.39 years; p=0.002). The occurrence of CSF related complications also influenced mortality (p=0.030), particularly postoperative hydrocephalus (p< 0.001). Inpatient hospital stay was longer in the subgroup of patients who developed CSF related complications (p=0.002). CONCLUSIONS: Tumor size was the only factor associated with the development of CSF related complications after surgery for posterior fossa tumors. In the subgroup of patients in which hydrocephalus was surgically treated preoperatively, the election of an external ventricular drain compared to other surgical modalities was associated with a higher rate of CSF related complications. The development of such complications, particularly hydrocephalus, was related with mortality.

Bacterial Infections↗
PubMed2003

[Evaluation of microsurgical treatment in a series of 121 intracranial aneurysms].

OBJECTIVE: The results obtained with therapy of intracranial aneurysms, in terms of morbidity and mortality, are very important when the patient has to choose between microsurgical techniques or endovascular management. The aim of this paper is to review the information regarding current microsurgical treatment of intracranial aneurysms, and presenting our experience over the last five years. MATERIAL AND METHODS: We studied 101 consecutive patients with 121 intracranial aneurysms admitted between 1996 and 2000 with the initial diagnosis of subarachnoid hemorrhage. We paid special attention to the day of admission from the onset of the symptomatic hemorrhage to the grade of Hunt&Hess scale and the possibility of early or delayed microsurgical treatment. The diagnosis was based on four vessels cerebral angiography and in a few cases with CT-angiography. All patients were treated by microsurgical technique and such treatment was completed by nimodipine, intensive care unit management and in some cases of postoperative suspected vasospasm, induced arterial hypertension was applied. Post surgical angiography was carried out in all patients to confirm the clipping of the cerebral aneurysm. The 12 months assessment was based on the Glasgow Outcome Scale (GOS). RESULTS: The 92.1% of the patients were admitted with a grade equal or below III in the Hunt&Hess scale. A 80% were operated within the 72 hours of admission and in the remaining cases, the surgical treatment was delayed due to a grade IV or V or to a medical contraindication. Four patients died (3.9%). At 12 months follow up, 88.9% presented a score I or II in the GOS. CONCLUSION: According to our results, there are a substantial improvements in the microsurgical treatment of cerebral aneurysms, specially in patients admitted early after the onset of the symptoms of their hemorrhage, who have a grade I to III in the Hunt&Hess scale and showed a good level of consciousness. We think that the improvement of our results are due to: l. the high percentage of patients admitted with grades I to III. 2. the high percentage of patients operated within the first 72 hours from the onset of their symptomatic hemorrhage. 3. surgery was always carried out by the same two experienced vascular neurosurgeons. 4. intraoperative measures taken to prevent the rupture of the aneurysm. 5. early administration of nimodipine, ICU management, doppler studies and in seldom cases, induced hypertension therapy to treat the vasospasm and postoperative hypotension.

Adolescent↗
PubMed2001

Arachnoid cysts: entrapped collections of cerebrospinal fluid variably communicating with the subarachnoid space.

Despite decades of investigation and discussion of the mechanisms involved in the pathophysiology of arachnoid cysts, fundamental issues concerning these entities remain poorly defined and controversial. Cine-mode magnetic resonance imaging (MRI) has shown two patterns of cerebrospinal fluid (CSF) flow within the cavity in patients harbouring arachnoid cysts. Some cysts present a harmonic flow with a patent flow entry zone. All these patients had intermittent, non-progressive and non-localizing symptoms requiring no surgery according to our criteria. The second pattern of CSF flow is more chaotic and is characterized by the presence of swirls throughout the entire cardiac cycle. This pattern is associated with a more disabling clinical picture. Some of these patients required surgical treatment. During surgery, an endoscope was used for inspection purposes revealing, above all, that arachnoid cysts always and variably communicate with the subarachnoid space. The CSF enters the cyst either through a patent flow entry zone or through minute perforations in areas more loosely packed of the arachnoid network that behave as a flexible mesh able to modify the area of flowing CSF. The slipstreams of CSF within arachnoid cysts may not be channelled properly leading to possible damage of the surrounding brain parenchyma.

Adolescent↗
PubMed2001

First blood meal of Ctenocephalides canis (Siphonaptera: Pulicidae) on dogs: time to initiation of feeding and duration.

Two experiments were conducted on dogs to evaluate interval to initiation and duration of the first blood meal of Ctenocephalides canis (Curtis). Percentage of fed male and female fleas was calculated for fleas held on dogs for 5, 15, 30, 60 min, 6, and 24 hr. Duration of first blood meal was also measured for individual fleas confined on dogs. When fleas were free in the hair coat, 21.2% had begun blood feeding within 5 min. After 1 hr, 72.5% of fleas had fed. After 6 hr, 95.2% of males and 100% of females had taken a blood meal, and 24 hr after deposition all fleas had fed. There was no significant difference between the 2 sexes. The mean delay between deposition and biting for fleas that began feeding within 15 min was 2 min 52 sec +/- 3 min 2 sec for female fleas and 3 min 8 sec +/- 2 min 45 sec for males. The mean duration of female and male meals was 5 min 3 sec +/- 3 min 41 sec and 6 min 9 sec +/- 6 min 8 sec, respectively. There was no significant difference between the 2 sexes. The dog flea took its blood meal on dogs more slowly than the cat flea did on cats; this meal was significantly longer for Ctenocephalides felis felis (Bouche) than for C. canis.

Animals↗
PubMed2000

Camino intracranial pressure monitor: prospective study of accuracy and complications.

OBJECTIVES: The fibreoptic device is a type of intracranial pressure monitor which seems to offer certain advantages over conventional monitoring systems. This study was undertaken to analyse the accuracy, drift characteristics, and complications of the Camino fibreoptic device. METHODS: One hundred and eight Camino intracranial pressure (ICP) devices, in their three modalities, were implanted during 1997. The most frequent indication for monitoring was severe head injury due to road traffic accidents. RESULTS: Sixty eight probe tips were cultured; 13.2% of the cases had a positive culture without clinical signs of infection, and 2.9% had a positive culture with clinical signs of ventriculitis. The most common isolated pathogen was Staphylococcus epidermidis. All patients were under cephalosporin prophylaxis during monitoring. Haemorrhage rate in patients without coagulation disorders was 2.1% and 15.3% in patients with coagulation abnormalities. Drift characteristics were studied in 56 cases; there was no drifting from the values expected according to the manufacturer's specifications in 34 probes. There was no relation between direction of the drift and duration of placement, nor between drift and time. CONCLUSIONS: Although the complication and drift rates were similar to those reported elsewhere, there was no correlation between the direction of the drift and long term monitoring despite the fact that some published papers refer to overestimation of values with time with this type of device.

Adolescent↗
PubMed1997

Neuroendoscopic management of pineal region tumours.

The management of pineal tumours remains controversial. During 1994 we treated four consecutive adults (16-44 yrs) harbouring a pineal tumour with a neuroendoscopic procedure. All of them presented with hydrocephalus. Pre-operative workup included cranial computerized tomography (CT), craniospinal magnetic resonance imaging (MRI) and serum levels of biological tumour markers. The endoscopic procedure consisted of a third ventriculostomy followed by biopsy with a flexible, steerable neuroendoscope. Histological diagnosis was achieved in three patients who no longer required a shunt device. Recorded complications were: bleeding during ventriculostomy that prevented us from obtaining a good sample for biopsy, short-term memory loss that cleared over a two-week period, and transient increase of pre-operative hemiparesis. Complications and morbidity are emphasized so as to be avoided with further technical experience. Neuroendoscopy affords a minimally invasive way of reaching three objectives by one-step surgery in the management of pineal region lesions: 1) CSF sample for analysis of tumour markers. 2) Treatment of hydrocephalus by third ventriculostomy. 3) Several biopsy specimens can be obtained identifying tumours which will require further open surgery or adjuvant radiation and/or chemotherapy.

Adolescent↗
PubMed1995

The natural history of arachnoid cysts: endoscopic and cine-mode MRI evidence of a slit-valve mechanism.

Arachnoid cysts are space-occupying lesions filled with CSF-like content and surrounded by a membrane resembling arachnoid matter. They are regarded as a development abnormality of the arachnoid, originating from a splitting or duplication of this membrane. However, precise etiology and natural history remain controversial. Different hypotheses have been developed including agenesis of brain structures, arachnoiditis, active fluid secretion, and pulsatile pump. We present a review of the literature concerning these items and report one case of a suprasellar arachnoid cyst in which a slit-valve mechanism was observed by means of cine-mode MRI preoperatively and confirmed during the endoscopic intervention.

Arachnoid↗