Biomedical subjects

A Lagares

Publications and source records attributed to A Lagares.

At least 19 recordsLinked to original sources

PubMed2006

[Magnetic resonance in moderate and severe head injury: comparative study of CT and MR findings. Characteristics related to the presence and location of diffuse axonal injury in MR].

INTRODUCTION: Cranial CT has been the most extended evaluation means for patients suffering head trauma. However, it has low sensitivity in the identification of diffuse axonal injury and posterior fossa lesions. Cranial MR is a potentially more sensitive test but difficult to perform in these patients, a fact that has hampered its generalised use. OBJECTIVE: To compare the identification capability of traumatic intracranial lesions by both diagnostic tests in patients with moderate and severe head injury and to determine which radiological characteristics are associated with the presence of diffuse injury in MR and their clinical severity. MATERIAL AND METHODS: 100 patients suffering moderate or severe head injury to whom a MR had been performed in the first 30 days after trauma were included. All clinical variables related to prognosis were registered, as well as the data from the initial CT following Marshall et al., classification. The MR was blindly evaluated by two neuroradiologists that were not aware of the initial CT results or the clinical situation of the patient. All lesions were registered as well as the classification following the classification of lesions related to DAI described by Adams et al. CT and MR findings were compared evaluating the sensitivities of each test. Factors related to the presence of diffuse injury in MR were studied by univariate analysis using chi2 test and simple correlations. RESULTS: MR is more sensitive than CT for lesions in cerebral white matter, corpus callosum and brainstem. It also detects a greater number of cerebral contussions. The presence of diffuse axonal injury depends on the mechanism of the trauma, being more frequent in higher energy trauma, specially in traffic accidents. Among the radiological characteristics associated to DAI the most clearly related is intraventricular haemorrhage. The presence of a deeper injury and a higher score in the scales of Adams is associated with a lower score in the GCS and motor GCS, and so with a worse level of consciousness and bigger severity of injury, confirming Ommaya's model.

Adolescent↗

PubMed2005

A comparison of different grading scales for predicting outcome after subarachnoid haemorrhage.

BACKGROUND: Most scales used to assess prognosis after subarachnoid haemorrhage (SAH) are based on the level of consciousness of the patient. Based on information from a logistic regression model, Ogilvy et al. developed a new grading scheme (Massachussetts General Hospital (MGH) Scale) which applied a simple scoring method to each prognostic factor considered relevant such as level of consciousness, age, quantity of blood in the first CT scan and size of the aneurysm. The purpose of this study is to introduce a modified version of the MGH scale, built up using factors applicable to every patient suffering SAH, and compare this new scale to the World Federation of Neurological Surgeons scale (WFNS), the Glasgow Coma Scale (GCS) scale for SAH and the MGH scale. METHOD: A series of 442 patients consecutively admitted to Hospital 12 de Octubre between January 1990 and September 2001 with the diagnosis of spontaneous SAH were retrospectively reviewed. Outcome was assessed by means of the Glasgow Outcome Scale measured six months after hospital discharge. Differences between grades of the WFNS, the GCS scale for SAH, the MGH scale and the new scale were computed by chi2 statistics. ROC curves were plotted for the different scales and their areas compared. FINDINGS: Both WFNS and GCS scales fail to present significant differences between most of their grades, while the proposed scale shows a constant inter-grade significant difference in predicting outcome. The proposed scale presents a significantly higher prognostic efficacy in the whole series of patients suffering spontaneous SAH, patients with idiopathic subarachnoid haemorrhage (ISAH) and patients with confirmed aneurysmal SAH. The MGH scale is not applicable to some groups of patients suffering SAH. INTERPRETATION: Grading scales including additional factors to the level of consciousness show higher prognostic efficacy. The proposed modification of the MGH scale makes it applicable to every patient suffering SAH without losing its prediction capability.

Adult↗

PubMed2005

Xanthogranuloma of the choroid plexus of the third ventricle: case report and literature review.

Xanthogranulomas of the choroids plexus (XG) are benign tumours of debatable etiology which become rarely symptomatic. Only few cases have been studied with MRI. A new case of xanthogranuloma of the third ventricle showing unusual features in the CT and MRI studies in a 47-year-old man with a 2-month history of gait and urinary disturbances and cognitive impairment is reported. The literature concerning clinical and neuroradiological presentation of intracranial xanthogranulomas is reviewed.

Choroid Plexus↗

PubMed2005

Acute subdural and intratemporal hematoma as a complication of percutaneous compression of the gasserian ganglion for trigeminal neuralgia.

The case of a 68 year-old man who developed a fatal intracranial hemorrhagic complication following percutaneous compression of the gasserian ganglion for trigeminal neuralgia is reported. The complication was likely related to improper placement of the Fogarty catheter into the temporal fossa out of the Meckel's cave. The anatomical structures at risk of damage by misplaced needle or catheter and some relevant technical details aimed to prevent extratrigeminal complications related with this and other percutaneous trigeminal lesioning procedures are analyzed.

Acute Disease↗

PubMed2005

Allergenic composition of the mite Suidasia medanensis and cross-reactivity with Blomia tropicalis.

BACKGROUND: Mites of the genus Suidasia are commonly found in house dust and may play an allergenic role in exposed populations. However, the allergenic potential and clinical impact of this genus has not been well established. The main objective of this project was to evaluate the allergenic role of the mite Suidasia medanensis. METHODS: An extract of S. medanensis was prepared and the allergen composition determined by immunoblot. Specific IgE antibody levels to S. medanensis and Blomia tropicalis were evaluated by radioallergosorbent (RAST) in the sera of 97 allergic asthmatic patients and 50 nonallergic subjects. Cross-reactivity between S. medanensis and the mite species B. tropicalis and Dermatophagoides farinae was investigated by RAST and immunoblot inhibitions. RESULTS: Seventy-one asthmatic patients sera (73.2%) had positive IgE reactivity to S. medanensis; 14 allergens with molecular weights ranging from 7.5 to 105 kDa were detected. The most frequently detected had molecular weights of 30-31 (54.8%), 24.5 (42%), 21 (38.7%), 47 (35%) and 58 kDa (35.5%). Blomia tropicalis extract inhibited IgE binding to nine of these identified allergens. Four B. tropicalis allergens were inhibited by S. medanensis extract. RAST inhibition results demonstrated a high degree of inhibition by B. tropicalis (87.2%) and D. farinae (90.9%) than by S. medanensis (32%). CONCLUSIONS: Sensitization to S. medanensis is common in asthmatic allergy patients in Cartagena. An important degree of cross-reactivity was established between S. medanensis and B. tropicalis, and D. farinae.

Animals↗

PubMed2005

[Value of serial CT scanning and intracranial pressure monitoring for detecting new intracranial mass effect in severe head injury patients showing lesions type I-II in the initial CT scan].

OBJECTIVE: To determine the incidence of pathological and intracranial pressure (ICP) changes during the acute posttraumatic period in severe head injury patients presenting with lesions Types I-II (TCDB classification) in the admission CT scan with the aim of defining the most appropriate strategy of sequential CT scanning and ICP monitoring for detecting new intra-cranial mass effect and improving the final outcome. MATERIAL AND METHODS: 56 patients (ages 15-80 years) consecutively admitted during a 2 years period were included. All had the initial CT scan < 24 hours after injury (mean interval = 150 min), several CT controls within the first days of the course and ICP monitoring after admission. Different epidemiological, clinical and radiological variables were recorded and deterioration defined as the development of sustained ICP over 20 mmHg requiring aggressive medical and/or surgical treatment was considered the dependent variable. Uni and multivariate analyses were made for determining the correlation between different parameters and the occurrence of deterioration and the final outcome as assessed with the GOS. RESULTS: The mean GCS score was 5 and 37% of the patients showed pupillary changes; 52.3% had peritraumatic hypotension-hypoxemia, 16.1% anemia and 12.3% coagulation changes. 50% of the patients showed petechial hemorrhages in the white matter or the brainstem, 66% SAH, 40% HIV, 39.3% brain contusion and 21.4% small extraaxial hematomas. 57.1% of the patients showed CT changes through the acute post-traumatic period consisting of new contusion (26.8% of the cases), growing of previous contusion (68.2%) or previous extraaxial hematoma (10.7%), and generalized brain swelling (10.7%). 64.9% of the patients made a favourable and 35.7% an unfavourable outcome. Overall, 27 (48.9%) patients developed deterioration, 21 (37.5%) with concurrent CT changes and 6 (10.7%) without new pathology as seen by the CT control. The remaining 29 (51.7%) patients in this series did not develop deterioration in spite that 11(19.6%) showed CT changes. The age, the initial score, the occurrence of peritraumatic hypotension-hypoxemia and coagulation disorders did not correlate with the risk of deterioration. By contrast, the presence of contusion at the initial CT scan (p= 0.01) and the occurrence of CT change (only generalized brain swelling, p= 0.003) significantly correlated with the risk of deterioration; in his turn deterioration increased by a factor of 10 (OR = 9.8) the risk of death and 7 out of the 8 patients who died developed intractable intracranial hypertension. The 8 (14.2%) patients requiring surgery showed simultaneous ICP deterioration and CT changes, but another 11 patients in a similar condition could be managed without surgery. With or without ICP deterioration, patients showing CT changes had a worse outcome than those without new pathologies, but the difference did not reach statistical significance, DISCUSSION AND CONCLUSIONS: Over 50% of the patients with initial Type I-II lesions developed new CT changes and nearly 50% showed intracranial hypertension during the acute posttraumatic period. Considering the high incidences of ICP and CT deterioration through the course, along with the absence of strong predictors and the discordances between CT and ICP changes (which were seen in 30.3% of the cases) we recommend ICP monitoring after admission in all patients and serial CT scanning at 2-4, 12, 24, 48 and 72 hours after injury with additional controls as indicated by clinical or ICP changes in all cases. Though it is clear that the presence of severe intra-cranial hypertension significantly increased the risk of death, the small size of the sample in this series prevented to assess to what extent the occurrence of new mass effect and/or raised ICP contributed to the development of moderate and severe disability in the survivors which were mainly due to the occurrence of diffuse axonal injury. Finally, demonstrating that sequential CT scanning and ICP monitoring improve the final outcome in this type of patients would require a prospective randomized trial which is impracticable for different reasons, among them the ethical ones.

Adolescent↗

PubMed2004

Lhermitte-Duclos disease and Cowden disease: clinical and genetic study in five patients with Lhermitte-Duclos disease and literature review.

BACKGROUND: Lhermitte-Duclos Disease (LDD) is an infrequent cerebellar disorder characterized by focal or diffuse enlargement of cerebellar folia presenting as a slowly growing mass in the posterior fossa. Over the past decade its association with Cowden disease (CD) has been recognized with increasing frequency. This latter disease is a genetic condition leading to the presence of multiple hamartomas and neoplasias which affect mainly the skin, thyroid, breast and genito-urinary and gastro-intestinal tracts. It has even been hypothesized that LDD and CD constitute a single entity. This work is aimed to analyse to what extent this association was present in patients treated for LDD at our institution. METHOD: We reviewed the medical records of five patients and performed clinical studies for CD manifestations, among them, genetic investigation for PTEN mutations. The International Cowden Consortium Criteria were applied for the diagnosis of CD. FINDINGS: Four of the five patients treated for LDD were also diagnosed of CD. The genetic study found PTEN mutations in two of them. Interpretation. LDD has been found to be closely related to CD in this series, in accordance with previous literature. However, the absence of CD diagnosis in one of the patients led us to suggest that, despite the strong association between these two diseases, LDD can also appear as an isolated condition.

Adult↗

PubMed2004

Meningiomas of the basal posterior fossa. Surgical experience in 80 cases.

INTRODUCTION: Despite recent improvements in microsurgical and radiotherapy techniques, treatment of basal posterior fossa meningiomas still carries an elevated risk of morbidity. We present our results in a series of patients with this type of tumor and review the recent literature looking for the results obtained with different approaches and the new tendencies and algorithms proposed for managing these challenging lesions. MATERIAL AND METHODS: We analyzed retrospectively the clinical presentation and outcome of 80 patients consecutively operated between 1979 and 2003 for basal posterior fossa meningioma (foramen magnum tumors excluded). All patients had preoperative CT scans and the majority MRI studies. A total of 114 operations were performed including two-stage operations, reoperation for recurrence, CSF diversion, and XII-VII anastomosis. The most commonly used approaches were lateral suboccipital retrosigmoid, subtemporal-transtentorial, frontotemporal pterional and supra-infratentorial presigmoid. Thirteen patients received postoperative radiotherapy. RESULTS: There were 59 (73.7%) women and 21 men (mean age = 51.5 years; range = 18-78 yrs). Most common presenting symptoms were cranial nerve dysfunction, gait disturbances and intracranial hypertension. The mean duration of symptoms was 2.9 years. 70% of the tumors were over 3 cm in size. Fifty patients (62.5%) had a complete resection, 22 (27.5%) subtotal resection (> 90% tumor volume removed), and 8 (10%) only partial resection. Postoperative complications included hematoma, CSF leak, and infection. Fifty four (67.5%) patients developed new or increased cranial nerve deficits and 12.5% somatomotor, somatosensory or cerebellar deficits immediately after surgery with subsequent improvement in most cases. Following initial surgery 67 patients made a good recovery, 10 developed variable degrees of disability and 3 died. Eleven patients died later in the course for tumor recurrence with or without reoperation, malignant meningioma or unrelated causes. There were 9 recurrences in the subgroup of patients having complete resection initially (mean follow-up = 8.6 years). The majority of patients having initial subtotal or partial resections have been managed without reoperation during a mean follow-up period of 6.5 years (radiosurgery and/or observation). DISCUSSION AND CONCLUSION: Current microsurgical and radiotherapy techniques allow either a cure or an acceptable control of basal posterior fossa meningiomas. In patients with tumor invasion of the cavernous sinus, extracranial extension, violation of the arachnoidal membranes in front of the brainstem, or encasement and infiltration of major arteries, a subtotal excision seems preferable followed by observation and/ or radiosurgical treatment. Apart from the patients age and the clinical presentation (symptomatic or not), the size and secondary extensions of the tumor must be taken into account for planning treatment in the individual patient.

Adolescent↗

PubMed2004

Unruptured dural arteriovenous malformation of the transverse-sigmoid sinus presenting with focal symptoms and coma.

We are presenting the case of a 63 year-old man with a dural arteriovenous malformation of the transverse sigmoid sinus who developed focal deficits followed by less localized symptoms such a disorientation, lethargy and eventually comatose status. Initial cerebral angiography showed retrograde filling of the cortical and deep cerebral venous system with marked delay in venous empting. Following embolization clinical symptoms completely cleared at the time that control angiography showed retrograde venous flow turning anterograde. Patient's symptoms recurred four months later when there was a relapse of retrograde cerebral venous drainage at the time he developed thrombosis of the superior longitudinal and right transverse sinuses. Sinus thrombosis and thrombosis of the central retinal artery were coincidental with hypercoagulability related to hyperhomocysteinemia. Since control angiography still showed persistence of the AV shunting radical excision of the involved dural sinuses was performed. The final outcome was excellent. The physiopathological mechanism responsible for neurological deficits in our patient most likely was ischemia of venous origin secondary to venous hypertension resulting from retrograde cerebral venous drainage. The clinical and angiographic presentation in few similar cases reported in the literature is reviewed.

Carotid Arteries↗

PubMed2004

Oligodendroglioma and multiple sclerosis. A case report.

BACKGROUND: The concurrence of multiple sclerosis (MS) and glioma is uncommon. Approximately 30 cases have been reported, but in only six of them the tumour was pure or mixed oligodendroglioma. The appearance of new neurological symptoms and signs in a patient with multiple sclerosis is usually attributed to a relapse of this disease and neuroradiological studies are not always performed. When done, the finding of a new focal mass lesion is usually interpreted as a pseudotumoural plaque. CASE REPORT: A 37-year-old man was admitted because of partial simple seizures and an enlarging intracranial mass. He had been diagnosed of MS eleven years earlier. A MRI study performed eight years before admission showed a large mass in the right frontal lobe which was thought to be a pseudotumoural plaque. Two years later, he developed simple partial motor seizures that were initially controlled with valproic acid. He remained well until three months before admission, when seizures reappeared with a poor response to valproic acid. A new MRI study showed an heterogeneous right frontal enlarging mass lesion. A primary neoplasm was suspected and a subtotal removal was performed. The pathological diagnosis was oligodendroglioma with a periferic demyelinating area. CONCLUSION: Atypical MRI lesions in a patient with MS must be carefully interpreted. Pseudotumoural plaques have been described both clinically and radiologically to be hardly distinguishable from a tumoural lesion and histological confirmation is often required. The association between MS and glioma is uncommon but it must be kept in mind when a mass lesion develops in a patient with MS.

Adult↗

PubMed2004

[Silent corticotroph adenomas: presentation of two cases that presented with pituitary apoplexy].

Among the group of pituitary adenomas surgically treated, about 25-30% are not associated with clinical or analytical findings of hormonal hypersecretion. The development of immunohistochemical techniques has allowed the demonstration of a subgroup of adenomas that show immunoreactivity against several hormones among the group of, apparently, non-functioning adenomas. This subgroup has been called silent adenomas. Silent adenomas positive for ACTH show a singular clinical picture and different from those adenomas producing Cushing's disease, as they present more frequently as macroadenomas, with more frequent pituitary apoplexy, invasion of cavernous or sphenoidal sinus and recurrences. We present two new cases of silent corticotroph adenomas in two female patients that presented with pituitary apoplexy, one of them after giving birth after a normal full-term pregnancy. Both of them presented with macroadenomas that invaded the sphenoidal and cavernous sinus. Although both tumors were immunoreactive for ACTH, none of the patients presented clinical or analytical findings compatible with Cushing's disease.

Adenoma↗

PubMed2004

[Postraumatic subdural collections: case report and review of the literature].

Posttraumatic and postcraniectomy subdural fluid collections have been usually described with the general term of hygroma. Recently, different clinical entities have been described, such as simple or complex hygroma, subdural effusion or external hydrocephalus, based on the mechanisms of formation of the fluid collection, its biochemical composition or the characteristics exhibited in modern imaging studies. However, there is no agreement in the literature regarding the use of these terms. We report a new case of a mixed posttraumatic and postcraniectomy subdural fluid collection and review the literature concerning these entities.

Brain Injuries↗

PubMed2003

Posterior fossa subdural hematoma mimicking intracerebellar hemorrhage.

Subdural hematomas of the posterior fossa are very rare and most cases are related to head injury. The influence of anticoagulation in cases of spontaneous development is well known. Although diagnosis is easily achieved by CT sean, atypical forms may lead to the wrong diagnosis of cerebellar hematoma. We present a case of a posterior fossa acute subdural hematoma occurring in an anticoagulated patient who was preoperatively misdiagnosed as an intracerebellar hemorrhage.

Aged↗

PubMed2003

[The new residency program in neurological surgery in Spain].

A new Residency Program in Neurological Surgery has been recently elaborated by the "Comisión Nacional de Neurocirugía" following the requirement of the National Council of Specialities. This new Program, which will replace the one proposed in 1992, has been designed in a similar way as those applied in countries providing the best neurosurgical training. Changes included deal with the definition of the speciality, and the introduction of new rotations,a resident Log Book, a Tutor with a well defined profil and commitments, a structured planning of academic and clinical objectives, a rotation or training in research, and a planning for continuous evaluation of the progress of the resident. It is likely that an appropriate application of the new Program in Spanish neurosurgical units with accreditation for training will result in formation of highly competent neurosurgeons. However, there are new challenges for improving neurosurgical training and the development of our speciality in Spain, as those related with new legislation regulating resident working hours, or some political decisions changing the mechanisms for controlling the number of resident positions per year.

Curriculum↗

PubMed2002

Construction of a Sinorhizobium meliloti strain carrying a stable and non-transmissible chromosomal single copy of the green fluorescent protein GFP-P64L/S65T.

A single copy of the green fluorescent protein (GFP)-encoding gene gfp-P64L/S65T under the control of the constitutive nptII promoter was introduced in a neutral region of the Sinorhizobium meliloti chromosome, between the genes recA and alaS. Within the same chromosomal region downstream of gfp-P64L/S65T a tetracycline (Tc) resistant cassette was also inserted. Both markers were very stable during at least 40 bacterial generations without any selective pressure. Similarly, the gfp-Tc cassette was stable and functional in all rhizobia that were recovered from alfalfa nodules. The GFP-associated fluorescence derived from the (single copy) chromosomal gfp-P64L/S65T allowed detection of rhizobia during the colonisation of the root, infection thread formation, and nodule development. The gfp-Tc rhizobia showed indistinguishable phenotypes for nodulation, competitiveness, and nitrogen-fixation from the parental strain. The labelling system described here can be used for the stable fluorescent tagging of S. meliloti strains allowing their detection in biologically complex soil environments.

Chromosomes, Bacterial↗

PubMed2002

Intratumoural bleomycin as a treatment for recurrent cystic craniopharyngioma. Case report and review of the literature.

INTRODUCTION: The majority of craniopharyngioma (CF) have a cystic component and only 10% are completely solid. In tumors with a large cystic component, stereotactic drainage or instillation of radioctive and/or chemotherapeutic agents have been used. Only several authors have reported the use of bleomycin for the treatment of cystic CF. CASE REPORT: The authors present the case of a nineteen years old patient with a recurrent cystic CF who was treated with intratumoral injections of bleomycin. The patient had been operated on three times before because of regrowth of the tumor. This last time he had a severe disturbance of his visual acuity and a huge regrowth of the cystic CF. An intracystic catheter stereotactically placed was connected to an Ommaya reservoir and, after assuring the impermeability of the cyst, bleomycin was administered through the reservoir up to a total dose of 45mg distributed in six doses. No complications were detected during and after the procedure. A MR performed 4 months after treatment showed a clear reduction in the size of the cyst but 10 months later a new regrowth of the cyst was detected by MR with no new signs or symptoms. A total dose of 30 mg divided in six doses was administered. No complications occurred. The MR 18 months after the first treatment showed the reduction in size of the tumor. The ophtalmological study showed almost normal visual acuity in both eyes. DISCUSSION: Although there is not an stablished protocol for the indication and the form of application of intracystic bleomycin, results with this treatment for cystic CF seem good in the literature. However, the risk of local complications after the administration of intratumoural bleomycin in these patients is around 10%, and some fatal toxic reactions have been recently reported. CONCLUSION: Intracystic administration of bleomycin is a valid option as adjuvant therapy for CF in patients with recurrences that are not surgical candidates because of the high risk of complications. The role of bleomycin as a primary treatment for CF and treatment protocols remain to be stablished with additional studies.

Adult↗

PubMed2002

[Arteriovenous malformation of the middle and posterior third section of the corpus callosum treated with embolization and surgery].

We are presenting the case of a 58 year-old woman with an arteriovenous malformation (AVM) of the middle and posterior thirds of the corpus callosum which had produced two episodes of bleeding before admission to our Department, when the patient was neurologically intact. The nidus was fed by the anterior and posterior pericallosal arteries draining through the left medial atrial vein to the vein of Galen, by parasagittal cortical veins to the superior sagittal sinus and by right temporal veins to the sphenoparietal sinus. The patient underwent embolization of the anterior and posterior feeders in two sessions separated by a week interval, and then the AVM was removed through a left paramedial parietooccipital craniotomy in a single stage. The patient showed transient mild short term memory deficit, but the final outcome was excellent.

Agenesis of Corpus Callosum↗

PubMed2002

[Idiopathic subarachnoid hemorrhage; comparison of different bleeding patterns and long-term outcome].

INTRODUCTION: Idiopathic subarachnoid haemorrhage (ISAH) represents approximately 15-30% of all subarachnoid haemorrhages. On the basis of the diagnostic CT and depending on the location of the subarachnoid bleeding, patients with ISAH may be classified into three groups: a) Patients with normal CT and diagnosis made by lumbar puncture (ISAHNCT); b) patients with a pure perimesencephalic pattern (ISAHPM) and c) patients with a bleeding pattern resembling that of aneurismatic rupture (ISAHA). This classification could permit the establishment of differences in the management and prognosis. OBJECTIVES: To describe the clinical and radiological characteristics of these three classes of patients and analyse their medium and long term outcome and moreover, compare these with those observed in patients suffering aneurysmal subarachnoid haemorrhage (ASAH). MATERIAL AND METHODS: A series of 122 patients consecutively admitted to Hospital 12 de Octubre Madrid between 1990 and 2000 with the diagnosis of ISAH were retrospectively reviewed. Patients were considered to have suffered ISAH when the first complete four vessel angiography did not show the presence of any aneurysm or vascular lesion responsible for the bleeding. Patients were classified depending on the pattern of bleeding into ISAHNCT, ISAHPM as described by Van Gijn et al., and ISAHA. The angiography study was repeated when: a) the first study was incomplete or had poor quality, b) vasospasm was present, c) in those patients who had an aneurysmal pattern of bleeding in the initial CT. Different clinical and radiological characteristics were recorded as well as complications that occurred during the hospital stay. Final outcome was evaluated by means of the Glasgow Outcome Score (GOS). With the purpose of comparing these clinical and radiological characteristics and the outcome of patients with ISAH with those suffering aneurysmal subarachnoid haemorrhage (ASAH), 294 patients diagnosed with ASAH during the same study period were also reviewed. RESULTS: 27% of patients admitted to our hospital with the diagnosis of non-traumatic subarachnoid hemorrhaged were diagnosed as ISAH. Of these, 41% presented with a ISAHA pattern, 39% ISAHPM and 20% ISAHNCT. The average age was similar in the different subgroups of SAH, being around 55 years. There was a greater frequency of male patients in the ISAHNCT and ISAHPM groups. In comparison with ASAH, ISAH characterises by patients presenting with less frequency a bad clinical grade and also loss of consciousness at stroke. There are fewer complications in patients with ISAH than ASAH, with a frequency of rebleeding and ischemia much less (5 and 6% respectively). Within the ISAH group, patients with ISAHA pattern of bleeding present more complications. Outcome is excellent for patients with ISAHNCT and ISAHPM, and rather worse for patients with ISAHA (median followup 5.8 years). CONCLUSIONS: This study confirms that the frequency of ISAH in our environment reaches the higher limit of that shown previously in the literature, replicating the results previously published by our group. Patients with ISAH have a better prognosis and a smaller risk of complications than patients with ASAH, the prognosis of patients with ISAHCTN and ISAHPM being particularly good. Patients with ISAHA present initially with a severe clinical situation, probably related to the bigger amount of bleeding, as well as a higher frequency of systemic complications, cerebral ischemia and hydrocephalus. However, if the absence of vascular lesions is confirmed, the long term prognosis is similar to that of the other subgroups of ISAH.

Aneurysm, Ruptured↗