Usefulness of third ventricle volumetry in patients with normal pressure hydrocephalus.

OBJECTIVE: To use third ventricle morphometric variables as a tool for the selection of patients with idiopathic normal pressure hydrocephalus (iNPH) who are candidates for ventriculoperitoneal shunts (VPS). MATERIAL AND METHODS: Retrospective study enrolling patients with iNPH. Katzman infusion test was performed and a Rout > 12 mmHg/mL/min was considered a positive result. The transverse diameter and the volume of the third ventricle were measured in the preoperative MRI. Postoperative improvement was assessed with the NPH score. The results were analysed with SPSS software. RESULTS: 52 patients with a mean age of 76 years were analysed. There was no difference in the diameter of the third ventricle among patients with a positive result and those with a negative result in the infusion test (12.28 vs 11.68 mm; p = 0.14). Neither were difference detected in the ventricle volume of both groups (3.6 vs 3.5cc; p = 0.66). Those patients who improved after VPS had a smaller third ventricle compared to those who did not respond after surgery (11.85 mm vs. 12.96 mm; p = 0.009). Diameter and volume of third ventricle present a significant strong correlation (Pearson correlation coefficient = 0.72; p < 0.0001). CONCLUSION: Morphometric variables of third ventricle may be useful in predicting a good response to VPS in patients with idiopathic normal pressure hydrocephalus.

Spontaneous CSF fistula as a manifestation of idiopathic intracranial hypertension.

INTRODUCTION: Spontaneous cerebrospinal fluid (CSF) fistula, of unknown origin, is a rare condition whose aetiology is increasingly related to idiopathic intracranial hypertension (IIH). This study tries to raise awareness that they should not be considered as two different processes, but that fistulas can be a form of debut, requiring a study and subsequent treatment. Repair techniques are described, as well as the study of HII. RESULTS: We treated 8 patients, 5 women and three men, aged between 46 and 72 years, with a diagnosis of spontaneous CSF fistula, four nasal and four otics who underwent surgical treatment. After repair, a diagnostic study was performed for IIH by MRI and Angio-MRI, presenting in all cases a transverse venous sinus stenosis. The intracranial pressure values obtained by lumbar puncture showed values of 20mm Hg or higher. All patients were diagnosed with HII. The one-year follow-up did not reveal any recurrence of the fistulas, maintaining a control of the HII. CONCLUSION: Despite their low frequency of both cranial CSF fistula and IIH, an association of both conditions should be considered by continuing the study and surveillance of these patients after fistula closure.

Association between RS3763040 polymorphism of the AQP4 and idiopathic intracranial hypertension in a Spanish Caucasian population.

Background: Idiopathic intracranial hypertension (IIH) is a condition of increased intracranial pressure of unknown aetiology. Principal symptoms are headache, visual disturbances, and obesity, together with elevated intracranial pressure. Unspecified MRI, despite normal ventricle size, suggests alterations in the water flux cellular mediated by the brain water channel aquaporin-4 (AQP4). The association among IIH, cerebral spinal fluid malfunction, reabsorption, and functional or regulatory modifications of AQP4 is a hypothesis not confirmed. Methods: Blood samples were collected from 72 Spanish Caucasian patients with IIH. A genetic association study was performed with bi-allelic SNPs rs1049305 and rs10244884 in AQ1 and rs2075575, rs3763043, and rs3763040 in AQ4. Genetic data were compared with 94 healthy Caucasian control. Statistics studies were assessed by Pearson's χ 2 tests for 2 × 2 (alleles) or 3 × 2 (genotypes) contingency tables. A P value < 0.05 was considered to be statistically significant. Results: Statistically significant differences were found when comparing the results of the rs3763040 polymorphism of the AQ4 locus of IIH patients with controls, in genotypic frequencies (P = 0.0442) and allele frequencies (P = 0.0171). Furthermore, a statistically significant difference (P = 0.0207) was found in individuals carrying and not carrying the minor allele (GG + GA individuals vs GG homozygotes). No statistically significant differences were found when comparing allele and genotypic frequencies for SNPs rs1049305 and rs10244884 of AQ1 and rs2075575 and rs3763043 of AQ4. Conclusions: The association of AQP4 and specifically of its polymorphic variant rs3763040 with IIH should be validated in other ethnic groups in order to assess more precisely the role of AQP4 in the etiopathogenesis of IIH.

Endoscopic third ventriculostomy limited by artery of Percheron.

The irrigation of the thalamus depends mainly on the thalamoperforating arteries. There are many anatomical variations in these arteries, the best known being the artery of Percheron. We report a case of a 13-year-old male presented with headache and decline in his mental status. Imaging features showed obstructive hydrocephalus secondary to a mass at the level of the mesencephalon so an endoscopic third ventriculostomy was performed. During the procedure a thalamoperforating artery was encountered at the level of the tuber cinereum limiting the perforation of the third ventricle floor. The present case emphasizes the importance of knowing the anatomy of these arteries and the identification of their main variants during neurosurgical procedures.

Recurrent meningeal malignant tumor: Assessment of differences in the solitary fibrous tumor/hemangiopericytoma spectrum through a case report.

Solitary fibrous tumors (SFTs) are neoplasms that grow from mesenchymal fusiform cells. In the central nervous system, meninges are the common origin of these neoplasms. Although literature reports mostly SFT as benign neoplasm, malignancy data have been described in recurrences or metastatic lesions. Definitive diagnosis includes immunohistochemical profiles assessing cellular positivity for CD34, vimentin, CD99 and Bcl-2. Recent studies have demonstrated NAB2-STAT6 gene fusion as a distinct molecular feature of SFT with overexpression of the fusion protein NAB2-STAT6 in nuclei of these cells. Since several years, pathologists have grouped SFT and hemangiopericytomas (HPC) as different phenotypes of the same entity although both neoplasms do not share numerous features. This article, based on a case of a recurrent malignant SFT, aims to emphasize differences in the SFT/HPC spectrum due to the diagnostic, therapeutic and prognostic implications.

Evaluating the optimal number of burr-holes for treating chronic subdural haematomas: good results from a single burr-hole?

INTRODUCTION: Chronic subdural haematomas (cSDH) are one of the most common types of traumatic intracranial lesion. Burr-hole craniostomy followed by closed-system drainage has become the treatment of choice. However, there is no definitive indication as to the number of burr-holes needed. Our aim was to to assess clinical and radiological outcomes taking into account the number of burr-holes made. MATERIAL AND METHODS: A retrospective single-centre-study was performed including patients treated for cSDH by performing burr-hole craniostomy from 2012 to 2018. After collecting data regarding demographics, comorbidities, and clinical and radiological records, haematomas were grouped depending on the number of burr-holes made (Group 1: single burr-hole; Group 2: double burr-holes). Clinical and radiological outcomes were statistically compared between groups, as well as the main complications. RESULTS: After collecting 171 patients, 205 cSDHs were analysed. 173 were treated with a single burr-hole (we called these Group 1) and 32 with double burr-holes (Group 2). No differences in preoperative characteristics were found between the groups, except for diabetes mellitus and previous antiplatelet/anticoagulation treatment. No radiological differences were found regarding haematoma volume (p = 0.7) or thickness (p = 0.3). Surgical site infection (p = 0.13), recurrence (p = 0.6), acute rebleeding (p = 0.25) and mortality (p = 0.94) were assessed without evidencing statistically significant differences. At the time of hospital discharge, most patients showed a remarkable clinical improvement, regardless of the number of burr-holes made (p = 0.7). CONCLUSIONS: This study suggests that cSDH can be efficiently evacuated by a single burr-hole craniostomy, a less invasive and shorter surgical procedure with quite good clinical outcomes and a low rate of complications.

Decompressive Craniectomy in Pregnant Women.

Malignant middle cerebral artery (MCA) infarction warranting decompressive craniectomy (DC) is unusual in the population younger than 40 years. Specifically, only a few cases affecting pregnant women have been described in the literature. We present the case of a 39-year-old woman in the 24th week of pregnancy who suffered a right malignant MCA infarction that eventually required DC. The patient delivered a healthy baby and underwent a second surgery for cranioplasty 7 months later. We present both this case and a review of the literature, including all cases of DC in pregnant women published to date.

Evaluation of the safety and effectiveness of a sealant hemostatic patch for preventing cerebrospinal fluid leaks in cranial surgery.

BACKGROUND: Cerebrospinal fluid (CSF) leak remains a significant source of morbidity after neurosurgical procedures. The objective is to evaluate the effectiveness and safety of a polyethylene glycol-coated collagen patch (PCC) in different neurosurgical procedures. METHODS: A retrospective, single-center cohort study in patients who underwent a cranial neurosurgical procedure. After collecting multiple data variables, patients were divided into two groups depending on the use of PCC as sealant on dural closure following procedures. RESULTS: Data from 230 patients were collected (PCC, 128; control group, 102). Incidence of CSF leakage was significantly lower in the PCC group (p < .001). Complications that were significantly lower in PCC than the control group included surgical infection (p = .022), and hydrocephalus (p = .017), as well as reduced rates of reintervention (p < .001) and shorter hospital stays (p = .028). Factors associated with a higher incidence of CSF leakage included posterior fossa procedures, reinterventions, and the need for CSF drainage placement. PCC reduced the risk of suffering CSF leakage by more than 75% (p = .002) once adjusted for age, surgical approach, type of cranial opening, reintervention, CSF drainage, dural substitute, and dural defect coverage. CONCLUSIONS: Our findings confirm PCC as an effective means of preventing CSF leakage following cranial neurosurgery with fewer associated complications.

Three-sectioning method: A procedure for studying hard tissues and large pieces under light and electron microscopy.

The histological study of hard pieces such as tendons and calcified lesions and tissues is a field that has been gaining increased attention owing to the rapid development of implantable prostheses, among other factors. In these studies, serial sectioning is utilized to detect areas of interest throughout the entire piece, as it enables the application of the appropriate light and electron microscopy techniques in these areas. We propose the "three-sectioning method" that subjects the pieces to three consecutive cycles of embedding and sectioning to localize and study the areas of interest, as an efficient technique for these histological studies. The pieces were first embedded in epoxy resin and then cut into thick sections (approximately 300 µm) for the first cycle. Next, areas of interest selected on these thick sections were re-embedded in epoxy resin to be sectioned again (second sectioning) to obtain a series of semithin sections (1-3 µm). These semithin sections are usually studied using the most relevant techniques for light microscopy. Smaller areas of interest are selected to be cut into ultrathin sections (60-90 nm) for transmission electron microscopy. If necessary, the selected areas of the semithin sections can be embedded again, and then cut into new ultrathin sections. The different kinds of sections we have described here may also be studied using scanning electron microscopy. This systematic method facilitates correlative microscopy from lower to higher magnifications along with the usage of a broad variety of histological techniques including electron microscopy.

Spinal cord compression secondary to traumatic intradural arachnoid cyst. / Compresión medular secundaria a quiste aracnoideo intradural de etiología traumática.

Spinal arachnoid cysts are rare entities, most of which have a congenital or spontaneous etiology. Secondary cases are infrequent and can constitute a cause of neurological deterioration several months or years after spinal trauma. We present the case of a male patient with traumatic spinal arachnoid cyst, together with a review of the cases published to date. Finally, we explain the different surgical options for this pathology relating them to the physiopathological theories that try to explain the origin of these lesions.

Las Aquaporinas Y El Sistema Nervioso Central / Aquaporins And System Nervous Central

RESUMEN El descubrimiento de las acuaporinas, que constituyen una familia de proteínas integrales de membrana, ha supuesto un cambio con respecto a la comprensión del transporte de agua en las membranas biológicas. La más importante es la aquaporina 4 (AQP4) en la que nos centraremos a continuación, aunque existen otras dos acuaporinas la 1y la 9. Estas acuaporinas tienen una gran importancia en la fisiología del control del volumen celular y los mecanismos de control osmótico de las células. También en el control del flujo de glicerol y otros solutos. Además, las alteraciones en su funcionamiento se han relacionado con distintas enfermedades del sistema nervioso central como la neuromielitis óptica, el edema cerebral, la hipertensión intracraneal idiopática o la hidrocefalia crónica del adulto entre otras. Se realiza una revisión sobre este tema.

ABSTRACT The discovery of aquaporins, which constitute a family of integral membrane proteins, has meant a change with respect to the understanding of water transport in biological membranes. The most important is aquaporin 4 (AQP4) which we will focus on below, although there are two other aquaporins, 1 and 9. These aquaporins are of great importance in the physiology of cell volume control and osmotic control mechanisms of the cells. Also in the control of the flow of glycerol and other solutes. In addition, alterations in its functioning have been related to various diseases of the central nervous system such as neuromyelitis optics, cerebral edema, idiopathic intracranial hypertension or chronic hydrocephalus of the adult among others. A review is made on this topic.