Speckle Tracking in Transcranial Ultrasound Allows Noninvasive Analysis of Pulsation Patterns of the Third Ventricle

Cerebrospinal fluid (CSF) flow is sensitive to many cerebral disorders. We aimed to develop a noninvasive bedside method to detect physiological and pathological CSF phenomena by measuring pulsation patterns of the third ventricle. By transcranial B-mode ultrasound, electrocardiography (ECG)-gated video loops of the third ventricle were acquired. "Speckle tracking" software was used to quantify the relative change of its width. We conducted measurements of nine cardiac cycles in 11 healthy subjects in sitting and in supine position during Valsalva maneuver to investigate the influence of an increased intracranial pressure on the relative deformation of the third ventricle. In one patient with occlusive hydrocephalus, 19 cardiac cycles were measured in sitting position before and after removal of a tumorous obstruction of the aqueduct of Sylvius. Healthy subjects expressed a pulse-related increased width of the third ventricle ([Formula: see text]: +5.69, 95% confidence interval [CI] = [4.38, 7.00]). No significant difference was found between the sitting and the supine position in healthy adults. In the preoperative state of occlusive hydrocephalus, we found a negative, pulse-related deformation ([Formula: see text]: -1.86, 95% CI = [-2.15, -1.58]) with delayed onset. After surgery, the deformation pattern resembled that of our healthy controls. The difference between pre- and postoperative condition was significant (p < 0.001). Transcranial B-mode sonography can be used to record small movements of the sidewalls of the third ventricle. This noninvasive bedside method is suitable to assess CSF pulsatility within the third ventricle and might be able to distinguish between physiological and pathological flows.

CSF flow pathways through the ventricle-cistern interfaces in kaolin-induced hydrocephalus rats-laboratory investigation

PURPOSE

The goal of this study was to identify direct cerebrospinal fluid (CSF) pathways in the interface between ventricles and cisterns. Such routes are hypothesized to be involved in alternative CSF flows in abnormal circumstances of CSF circulation.

METHODS

Chronic obstructive hydrocephalus models were induced in ten Sprague-Dawley rats with kaolin injection into the cisterna magna. Three weeks after the kaolin injection, when thick arachnoid fibrosis obliterated the fourth ventricular outlets, cationized ferritin was stereotactically infused as a tracer into the lateral ventricle in order to observe the pathways from the ventricles to the subarachnoid space. Animals were killed in 48 h and brains were sectioned. CSF flow pathways were traced by the staining of ferritin with ferrocyanide.

RESULTS

Eight out of ten rats developed hydrocephalus. The subarachnoid membranes of the convexity and basal cisterns were severely adhered such that most of the ferritin remained in the ventricles whereas basal and convexity cisterns were clear of ferritin. In six out of the eight hydrocephalus rats, ferritin leaked from the third ventricle into the quadrigeminal cistern, and from the lateral ventricle into the ambient cistern.

CONCLUSIONS

The interfaces between the third ventricle and the quadrigeminal cistern, and between the lateral ventricle and the ambient cistern appear to be alternative CSF pathways in a pathologic condition such as obstructive hydrocephalus.

Symptomatic colloid cysts in the third ventricle of monozygotic twins

In this case report we describe colloid cysts in the third ventricles of monozygotic twin sisters. They were 26 years old when their condition was discovered. One woman was admitted to us on an emergency basis, with signs of high intracranial pressure such as unconsciousness and extension posturing. Her sister was also brought to the hospital since she had a history of attacks of headache. They were both operated with removal of the colloid cysts, and the clinical courses are described in the case report. In reviewing the literature another 30 familial cases were found. Of these were two pairs of monozygotic and one pair of dizygotic twins.

Voluntary exercise induces neurogenesis in the hypothalamus and ependymal lining of the third ventricle

In the adult hypothalamus and ependymal lining of the third ventricle, tanycytes function as multipotential progenitor cells that enable continuous neurogenesis, suggesting that tanycytes may be able to mediate the restoration of homeostatic function after stroke. Voluntary wheel running has been shown to alter neurochemistry and neuronal function and to increase neurogenesis in rodents. In the present study, we found that voluntary exercise improved the survival rate and energy balance of stroke-prone spontaneously hypertensive rats (SHRSP/Kpo). We also investigated the effect of exercise on the proliferation and differentiation of hypothalamic cells using immunoreactivity for tanycytes and neural markers. The proliferation of elongated cells, which may be the tanycytes, was enhanced in exercising SHRSP compared to sedentary rats before and after stroke. In addition, the proliferation of cells was correlated with the induction of fibroblast growth factor-2 in the subependymal cells of the third ventricle and in the cerebrospinal fluid. Some of the newborn cells of exercising SHRSP showed differentiation into mature neurons after stroke. Our results suggest that voluntary exercise correlates with hypothalamic neurogenesis, leading to recovery of homeostatic functions in the adult brain after stroke.

[Transcranial dopplerography in the combination with echopulsography in the assessment of intracranial and cerebral perfusion pressure in patients with intracranial hemorrhages]

OBJECTIVE

To study the possibilities of common ultrasound diagnostic methods in the evaluation of intracranial pressure (ICP) and central perfusion pressure (CPP) and to search for the ways of increasing the accuracy of these methods.

MATERIAL AND METHODS

Thirty-eight patients, aged 28-66 years admitted to a neuroreanimation department of a hospital due to acute intracranial vascular and traumatic hemorrhages were examined. An instrumental study included transcranial dopplerography (TCDG) and digital echoencephalography. Accuracy of measurement was evaluated for ICP and CPP in clinical conditions.

RESULTS

The data obtained confirm the possibility of quantitative assessment of ICP and CPP using TCDG. We suggest a new formula for more precise calculation of CPP.

CONCLUSION

The complex use of noninvasive ultrasound methods allow in most cases to measure with acceptable accuracy and assess the degree of intensity of ICP and CPP changes at the acute stage of intracranial hemorrhages.

Endoscopic third ventriculostomy in the presence of large or giant basilar artery aneurysms

BACKGROUND

Endoscopic third ventriculostomy (ETV) is an effective treatment of obstructive hydrocephalus (OH). However, the presence of a large or giant basilar aneurysm is generally considered a contra-indication to ETV for treating hydrocephalus. We report the feasibility and efficacy of ETV for the treatment of hydrocephalus in the presence of such aneurysms.

METHODS

We performed a retrospective chart analysis of patients that underwent ETV for large or giant basilar aneurysm-associated hydrocephalus between January 2003 and January 2011.

RESULTS

During this period, 78 patients were treated by ETV. Of these, three patients presented with symptomatic hydrocephalus associated with a large giant basilar aneurysm (n = 3). Two of those patients had a history of previous subarachnoid hemorrhage (SAH) with intraventricular hemorrhage (IVH) 11 years and 13 years before ETV. Both aneurysms were embolized preoperatively. The third patient presented with OH due to an unruptured basilar artery aneurysm. There was no operative complication and symptoms resolution was observed in all patients at last follow-up.

CONCLUSIONS

ETV is a safe and effective alternative to ventriculo-peritoneal shunting in patients with hydrocephalus caused by large or giant basilar artery aneurysms. In addition, a history of SAH/IVH should not be considered a contra-indication to ETV.

[Identification of highly specific electroencephalographic patterns in patients with neuroepithelial tumors of the III ventricle by algorithmic methods]

An algorithm was suggested for identifying highly specific electroencephalographic (EEG) patterns in neurooncologic patients. The algorithm provides selection of patients with their further classification into main and control groups based on the already existing database of EEG indicators; requests to it; generation of mono-indicator candidates for EEG-patterns on the basis of a 4-dipole table for selecting and verifying sensitive and specific EEG patterns and outlining the best ones. Our material included 368 patients with basal-diencephalic tumors. Algorithmic methods revealed new EEG patterns in patients with different anatomical and topographical variants of neuroepithelial tumors in the III ventricle. We think it reasonable to use the revealed syndromes to improve diagnosis and identify pathophysiological basis of clinical syndromes.

New ependymal cells are born postnatally in two discrete regions of the mouse brain and support ventricular enlargement in hydrocephalus

A heterogeneous population of ependymal cells lines the brain ventricles. The evidence about the origin and birth dates of these cell populations is scarce. Furthermore, the possibility that mature ependymal cells are born (ependymogenesis) or self-renewed (ependymal proliferation) postnatally is controversial. The present study was designed to investigate both phenomena in wild-type (wt) and hydrocephalic α-SNAP mutant (hyh) mice at different postnatal stages. In wt mice, proliferating cells in the ventricular zone (VZ) were only found in two distinct regions: the dorsal walls of the third ventricle and Sylvian aqueduct (SA). Most proliferating cells were monociliated and nestin+, likely corresponding to radial glial cells. Postnatal cumulative BrdU-labeling showed that most daughter cells remained in the VZ of both regions and they lost nestin-immunoreactivity. Furthermore, some labeled cells became multiciliated and GLUT-1+, indicating they were ependymal cells born postnatally. Postnatal pulse BrdU-labeling and Ki-67 immunostaining further demonstrated the presence of cycling multiciliated ependymal cells. In hydrocephalic mutants, the dorsal walls of the third ventricle and SA expanded enormously and showed neither ependymal disruption nor ventriculostomies. This phenomenon was sustained by an increased ependymogenesis. Consequently, in addition to the physical and geometrical mechanisms traditionally explaining ventricular enlargement in fetal-onset hydrocephalus, we propose that postnatal ependymogenesis could also play a role. Furthermore, as generation of new ependymal cells during postnatal stages was observed in distinct regions of the ventricular walls, such as the roof of the third ventricle, it may be a key mechanism involved in the development of human type 1 interhemispheric cysts.

Structural pathology underlying neuroendocrine dysfunction in schizophrenia

Polydipsic hyponatremic schizophrenic (PHS) patients exhibit altered neuroendocrine activity that has been linked to their life-threatening water imbalance, as well as to impaired function and reduced volume of the anterior hippocampus. Polydipsic patients without hyponatremia (polydipsic normonatremic schizophrenics: PNS) exhibit similar, albeit less marked, changes in neuroendocrine activity and anterior hippocampal function, but not reduced anterior hippocampal volume. Indeed, reduced anterior hippocampal volume is seen in patients with normal water balance (nonpolydipsic normonatremic schizophrenics: NNS) whose neuroendocrine activity and anterior hippocampal function differ markedly from those with polydipsia. In an effort to reconcile these findings we measured hippocampal, amygdala and 3rd ventricle shapes in 26 schizophrenic patients (10 PNS, 7 PHS, 9 NNS) and 12 healthy controls matched for age and gender. Bilateral inward deformations were localized to the anterior lateral hippocampal surface (part of a neurocircuit which modulates neuroendocrine responses to psychological stimuli) in PHS and to a lesser extent in PNS, while deformations in NNS were restricted to the medial surface. Proportional deformations of the right medial amygdala, a key segment of this neurocircuit, were seen in both polydipsic groups, and correlated with the volume of the 3rd ventricle, which lies adjacent to the neuroendocrine nuclei. Finally, these structural findings were most marked in those with impaired hippocampal-mediated stress responses. These results reconcile previously conflicting data, and support the view that anterior lateral hippocampal pathology disrupts neuroendocrine function in polydipsic patients with and without hyponatremia. The relationship of these findings to the underlying mental illness remains to be established.

Visual field deficit due to downward displacement of optic chiasm

Visual disturbance in hydrocephalus is typically due to raised intracranial pressure. We describe a patient who presented with marked loss of peripheral visual fields, but without features suggestive of raised intracranial pressure. MR scan showed an enlarged third ventricle and a downward displacement of the optic chiasm, Chiari II malformation. These radiological changes and the visual field deficits reversed after endoscopic third ventriculostomy and foramen magnum decompression. These observations support the view that the treatment of the hydrocephalus in such patients can help to reverse the change in the position of the optic chiasm and the visual field deficits.

Endoscopic third ventriculostomy for malfunction in previously shunted infants

INTRODUCTION

The usage of endoscopic third ventriculostomy (ETV) as an alternative to shunt revision in the management of shunt malfunction is gaining popularity.

METHODS

We review the clinical data of 45 patients who underwent ETV because of ventriculopritoneal shunt malfunction at Hacettepe University School of Medicine Department of Neurosurgery between January 2002 and August 2007. Medical records of the patients were retrospectively studied.

RESULTS

Male-to-female ratio was 23/22. The cause of the hydrocephalus was aqueduct stenosis in 21 (46.9%) patients, newborn meningitis in nine (20%) patients, tumor in six (13.3%) patients, newborn intraventricular hemorrhage in four (8.8%) patients, myelomeningocele in three (6.6%), and trauma in two (2.2%) patients. Of the patients, 27 (60%) had triventricular and 18 (40%) had tetraventricular hydrocephalus at their radiologic evaluation. On admission, all patients had at least one episode of shunt dysfunction prior to ETV. Follow-up duration after surgery was 1-5 years (mean 2.46 +/- 1.64 years). Postoperative cerebrospinal fluid flow studies using the cine-PC MR imaging were performed on all patients. The overall success rate for ETV after shunt malfunction was 80% with 36 patients and failure rate was 20% with nine patients. All of these nine patients had undergone shunt insertion within 10 days-1 month after unsuccessful ETV.

CONCLUSION

Endoscopic third ventriculostomy is an effective treatment for shunt malfunction.

Rhinorrhoea from a frontal encephalocele after reduction of high intracranial pressure

Acquired non-traumatic frontal sinus encephaloceles are very rare lesions that are usually caused by a tumour or hydrocephalus. We present a 31-year-old woman with a frontal sinus encephalocele who developed rhinorrhoea after a ventriculo-peritoneal shunt to treat her hydrocephalus and underwent radiotherapy for a tectum tumour.

Reduced anterior hippocampal formation volume in hyponatremic schizophrenic patients

Diminished hippocampal volume occurs in the anterior segment of some schizophrenic patients, and in the posterior segment in others. The significance of hippocampal pathology in general and these segmental differences in specific is not known. Several lines of evidence suggest anterior hippocampal pathology underlies the life-threatening hyponatremia seen in a subgroup of patients with schizophrenia; therefore our goal was to determine if this region was preferentially diminished in hyponatremic patients. We studied seven polydipsic hyponatremic, ten polydipsic normonatremic, and nine nonpolydipsic normonatremic schizophrenic inpatients, as well as 12 healthy controls. All underwent structural scanning on a high resolution (3.0 T) magnetic resonance imaging (MRI) scanner. Hippocampal formation, amygdala, and third ventricle volumes were manually traced in each subject. The hippocampus was divided at the posterior extent of the uncus, and all structural volumes were corrected for whole brain volume and other significant recognized factors (i.e., age, gender, height, parental education). Despite being overhydrated, anterior hippocampal formation volume was diminished in those with polydipsia and hyponatremia relative to each of the other three groups. Third ventricle volume was larger in this group than in healthy controls but similar to the two patient groups. Posterior hippocampal and amygdala volumes did not differ between groups. Other potential confounds (e.g., water imbalance) either had no effect or accentuated these differences. We conclude the anterior hippocampal formation is smaller in hyponatremic schizophrenic patients, thereby linking an important and objective clinical feature of schizophrenia to a neural pathway that can be investigated in animal models. The findings strengthen the hypothesis that anterior hippocampal formation pathology disrupts functional connectivity with other limbic structures in schizophrenia.

Neuro-endoscopic management of intraventricular neurocysticercosis (NCC)

OBJECTIVE

Various approaches including endoscopy have been used for the treatment of intraventricular and cisternal NCC. We present our technique of Neuro-endoscopic management of intraventricular NCC.

METHODS

Twenty-one cases, 13 females and 8 males (age range 12-50 years; mean, 25.7 years), of intraventricular NCC [lateral (n = 6), third (n = 6), fourth (n = 10) ventricles including a patient with both lateral and third ventricular cysts] producing obstructive hydrocephalus formed the group of study. Gaab Universal Endoscope System along with 4 mm 0 degrees and 30 degrees rigid telescopes were used through a frontal burr-hole for removal of intraventricular including intra-fourth ventricular (n = 10) NCC. Endoscopic third ventriculostomy (ETV) was done for internal cerebrospinal fluid (CSF) diversion. Average follow up was 18 months.

RESULTS

Complete (n = 18) or partial (n = 2) removal of NCC was done in 20 patients, while a cyst located at foramen of Monro slipped and migrated to occipital or temporal horn in 1 patient. Thirty-degree 4-mm rigid telescope provided excellent image quality with ability to address even intra-fourth ventricular NCC through the dilated aqueduct using a curved tip catheter. No patient required further surgery for their hydrocephalus. There was no operative complication and post-operative ventriculitis was not seen in any case despite partial removal of NCC.

CONCLUSION

Neuro-endoscopic surgery is an effective treatment modality for patients with intraventricular NCC. It effectively restores CSF flow and is capable of removing cysts completely or partially from accessible locations causing mass effect. Partial removal or rupture of the cyst does not affect the clinical outcome of the patients.

Neuroendoscopic management of a solitary pineal region tumor. Case report of an adenocarcinoma metastasis

The present case describes a two-step endoscopic management of hydrocephalus and diagnosis of a single pineal region metastasis arising from a gastric adenocarcinoma. A 62-year-old man presenting with signs of subacute obstructive hydrocephalus from a pineal region mass had at first been treated with an endoscopic third ventriculostomy. As cerebrospinal fluid tumor markers (alpha-fetoprotein, beta-human chorionic gonadotropin) were negative, an endoscopic biopsy of the pineal region tumor was performed through a more anterior frontal burr hole. Pathology showed an adenocarcinoma and primary tumor work-up revealed an unsuspected gastric tumor, the pathology of which matched with the intracranial metastasis. The present report emphasizes the role of neuroendoscopy in pineal region tumors and reports a rare case of a solitary gastric adenocarcinoma metastasis in this location.

Transcavum septum pellucidum interforniceal approach for the colloid cyst of the third ventricle

BACKGROUND

Despite their unfavorable locations, lesions of the third ventricle can be successfully removed via an interhemispheric, transcallosal approach. In cases with normal ventricular anatomy, this approach requires unilateral or bilateral identification of the foramen of Monro.

TECHNIQUE

However, in the presence of abnormal ventricular configuration such as cavum septum pellucidum (CSP), this basic knowledge needs to be modified. After routine callosotomy, there may be a confusion while entering the CSP due to the invisualization of ventricular landmarks such as the foramen of Monro, thalamostriate vein, and choroid plexus. The floor of the CSP is formed by the fornices, and a direct approach to the interforniceal area is easier via the CSP. But the interforniceal approach is not a routine way to reach the third ventricle, which has higher risks than other modalities.

CONCLUSION

This approach should be planned and used in selected cases of the CSP. Opening of the walls of CSP is recommended both to expose both the foramen of Monro and to gain safe access to the third ventricle before manipulating the interforniceal area.

Two-stage treatment of a tectal ganglioglioma: Endoscopic third ventriculostomy followed by surgical resection

Tumours of the quadrigeminal plate in adults are usually benign. Nevertheless, obstructive hydrocephalus due to compression of the Sylvian aqueduct is an almost invariable early finding. Whether or not direct excision is undertaken, temporary or permanent treatment of the hydrocephalus is warranted. Endoscopic third ventriculostomy is an alternative to insertion of a shunt and provides both acute and long-term relief of hydrocephalus-related symptoms. We chose a two-stage approach for treating a tectal ganglioglioma in an adult: endoscopic third ventriculostomy followed by surgical excision. The advantages and disadvantages of each therapeutic strategy are discussed.

Delayed pneumocephalus following shunting for hydrocephalus

Delayed pneumocephalus is a rare but well-reported complication of cerebrospinal fluid diversion procedures. In most cases the air enters the intracranial cavity via a skull base defect. We report a case of hydrocephalus secondary to aqueduct stenosis. The patient developed pneumocephalus 2 months after successful placement of a ventriculoperitoneal shunt. We describe an attempt at endoscopic diagnosis and repair of the fistula. This was unsuccessful, presumably because the defect was too small to localize even with the use of intrathecal fluorescein. We subsequently performed a conventional craniotomy and anterior fossa repair with placement of an antisiphon device. We suggest that in certain cases, when patients present with long-standing hydrocephalus, it may be advisable to insert either a high-pressure valve or antisiphon device as a primary measure.

Neurofiberscopic biopsy of tumors of the pineal region and posterior third ventricle: indications, technique, complications, and results

OBJECTIVE

Evaluation of results of the neurofiberscopic biopsy of tumors of the pineal region and posterior third ventricle.

METHODS

From 2001 to 2004, 23 patients (mean age, 30.6 yr) with tumors located in the pineal region or posterior third ventricle underwent neurofiberscopic biopsy with simultaneous third ventriculostomy. The procedure was indicated for verification of the histological diagnosis of the neoplasm, which was planned to be treated by radiotherapy and/or chemotherapy without open surgery (eight patients), establishment of the pathological diagnosis for further choice of the most appropriate treatment strategy (11 patients), differentiation of the recurrent neoplasm and radiation necrosis (two patients), and decompression of the large tumor-associated cyst (two patients). In six previously shunted patients, substitution of the ventriculoperitoneal shunt on the third ventricle stoma was performed.

RESULTS

There was no postoperative mortality or permanent morbidity. In all cases, the obtained tissue sample was sufficient for pathological diagnosis. Transient postoperative complications included fever (15 patients), nausea and vomiting (three patients), and diplopia (one patient). On the long-term follow-up, delayed third ventricular stoma failure caused by tumor regrowth and scar formation was found in one patient, and dissemination of the malignant glioma through the subarachnoid space was found in another patient.

CONCLUSION

Neurofiberscopic biopsy represents a useful method for sampling of tumors of the pineal region and posterior third ventricle, which can be effectively used in both previously shunted and shunt-free patients.

Study of tryptophan metabolism via serotonin in cerebrospinal fluid of patients with noncommunicating hydrocephalus using a new endoscopic technique

By a recent minimally invasive neuroendoscopic technique, the cerebral ventricles have been reached in a quick, reliable, and harmless way, making possible the study of cerebrospinal fluid (CSF) of the lateral ventricles and, above all, the CSF adjacent to the walls of the third ventricle. Tryptophan, 5-hydroxytryptophan, serotonin (5-HT), and 5-hydroxyindoleacetic acid (5-HIAA) were measured in CSF by HPLC equipment. Twenty-six patients affected with noncommunicating hydrocephalus were enrolled in the study and, as controls, 28 subjects not suffering from any neurological disease. The concentrations of tryptophan were higher in right ventricular CSF than in lumbar CSF (P < 0.01). 5-HT was detectable in the CSF of the right ventricle of hydrocephalic patients. 5-HIAA was higher in right ventricular CSF than in cisternal and lumbar CSF (P < 0.01), both in controls and in hydrocephalic patients. However, there was a higher concentration of 5-HIAA in right ventricular (P < 0.05) and cisternal (P < 0.01) CSF in hydrocephalic patients in comparison with controls. In the CSF samples withdrawn during neuroendoscopy, 5-HT presented the highest concentrations in the pineal recess. The highest amounts of 5-HIAA were found in the choroid plexus, third and right ventricles, pituitary recess, and aqueduct, and the lowest in pineal recess, subarachnoid space, infundibulum, and interpeduncolar cistern. These results provide new insight into the fate of tryptophan and its metabolites via serotonin in the CSF and suggest the feasibility of the new neuroendoscopic technique for brain metabolic studies.

Outcome Prediction of Third Ventriculostomy: A Proposed Hydrocephalus Grading System

An important factor in making a recommendation for different treatment modalities in hydrocephalus patients (VP shunt versus endoscopic third ventriculostomy) is the definition of the underlying pathology which determines the prognosis/outcome of the surgical procedure. Third ventriculostomies (3rd VS) are successful mainly in obstructive hydrocephalus but also in some subtypes of communicating hydrocephalus. A simple, easily applicable grading system that is designed to predict the outcome of 3rd VS is proposed. The hydrocephalus is graded on the basis of the extent of downward bulging of the floor of the third ventricle, which reflects the pressure gradient between the 3rd ventricle and the basal cisterns, presence of directly visualised CSF pathway obstruction in MRI, and the progression of the clinical symptoms resulting in five different grades. In this proposed grading system, grade 1 hydrocephalus subtype shows no downward bulged floor of the 3rd ventricle, no obstruction of the CSF pathway, and no progressive symptoms of hydrocephalus. There is no indication for 3rd VS. Grades 2 to 4 show different combinations of the described parameters. Grade 5 subtype shows a markedly downward bulged floor of the 3rd ventricle and direct detection of the CSF pathway obstruction (i.e., aqueductal stenosis) with progressive clinical deterioration. Retrospective application of this grading scheme to a series of 72 3rd VS has demonstrated a high correlation with the outcome: The success rate in grade 3 reached 40%, in grade 4: 58%, and in grade 5: 95%. This standardised grading system predicts the outcome of 3rd VS and helps in decision making for 3rd VS versus VP shunting.

The effects of fenestration of the interpeduncular cistern membrane arousted to the opening of lamina terminalis in patients with ruptured ACoA aneurysms: a prospective, comparative study

BACKGROUND

The incidence of chronic hydrocephalus requiring shunt placement is a well-known and common complication of aneurysmal subarachnoid hemorrhage (aSAH). It was suggested that fenestration of the lamina terminalis (LT) during microsurgery for aSAH may be associated with a reduced rate of shunt-dependent chronic hydrocephalus (SDCH). We analyzed that, fenestrations of the LT and Liliequist membrane (LM) would reduce rate of SDCH and improve rate of favorable outcome.

METHODS

145 patients who were analyzed in the study were treated in our department with ruptured anterior communicating artery (ACoA) aneurysms. We compared the rate of shunting and clinical outcome in patients in whom only fenestration of the LT (Group 1) was performed with that in patients in whom fenestrations of both the LT and LM (Group 2) were performed.

RESULTS

Chronic hydrocephalus requiring shunting amounted to 9.8% (7 patients) in Group 1 and 4% (3 patients) in Group 2 (p=0.203). Also, there were no differences in the rate of shunt dependent hydrocephalus between the two groups in patients with Fisher's CT grades 3 (p=0.343) and 4 (p=0.667), and HH grades 4 (p=0.306) and 5 (p=0.361). Favorable clinical outcomes were observed with rates of 74.6% in Group 1 and 79.7% in Group 2 (p=0.693). Also there were no differences in the rates of favorable clinical outcome between the two groups in patients with Fisher's CT grades 3-4, HH grades 4-5.

CONCLUSIONS

Our study shows that fenestration of the LM coupled with the opening of the LT reduced-relatively-the incidence of SDCH; this however was not significant. This positive effect was particularly noticeable in patients in whom a cisternal "overflow" was observed at surgery when opening the LM. This corresponded to cases with ventricular dilatation and a IVth ventricle with clots.

Cavernoma of the foramen of Monro

✓The authors report on a patient who presented with an intraventricular mass located at the level of the foramen of Monro. The clinical presentation and neuroimaging appearance of the mass led to an initial diagnosis of colloid cyst. A neuroendoscopic approach offered a direct view of the ventricular lesion, which was found to be a cavernous angioma partially occluding the foramen of Monro. The lesion was then removed using microsurgery. In this report the authors highlight possible pitfalls in the diagnosis of some lesions of the third ventricle, and the possible advantages of using a combined endoscopic and microsurgical technique when approaching such lesions.

A Probabilistic Functional Atlas of the VIM Nucleus Constructed from Pre-, Intra- and Postoperative Electrophysiological and Neuroimaging Data Acquired during the Surgical Treatment of Parkinson’s Disease Patients

We have previously introduced a concept of a probabilistic functional atlas (PFA) to overcome limitations of the current electronic stereotactic brain atlases: anatomical nature, spatial sparseness, inconsistency and lack of population information. The PFA for the STN has already been developed. This work addresses construction of the PFA for the ventrointermediate nucleus (PFA-VIM). The PFA-VIM is constructed from pre-, intra- and postoperative electrophysiological and neuroimaging data acquired during the surgical treatment of Parkinson's disease patients. The data contain the positions of the chronically implanted electrodes and their best contacts. For each patient, the intercommissural distance, height of the thalamus and width of the third ventricle were measured. An algorithm was developed to convert these data into the PFA-VIM, and to present them on axial, coronal and sagittal planes and in 3-D. The PFA-VIM gives a spatial distribution of the best contacts, and its probability is proportional to best contact concentration in a given location. The region with the highest probability corresponds to the best target. The PFA-VIM is calculated with 0.25-mm3 resolution from 107 best contacts in two situations: with and without lateral compensation against the width of the third ventricle. For the PFA-VIM compensated laterally, the anterior, lateral and dorsal coordinates of the mean value are (in mm) 6.24, 13.83, 1.68 for the left VIM and 6.54, -13.84, 2.10 for the right VIM. The coordinates of the mean value of the highest probability region along with the highest number of the best contacts (P) are: 6.25, 14.25, 1.75, P = 16, for the left VIM, and 6.0, -14.0, 1.00, P = 18, for the right VIM. The coordinate system origin is at the posterior commissure. For the PFA-VIM not compensated laterally, the coordinates of the mean value are 6.24, 13.99, 1.68 for the left VIM and 6.53, -14.13, 2.10 for the right VIM. The coordinates of the mean value of the highest probability region along with the highest number of the best contacts are 5.58, 13.67, 1.33, P = 14, for the left VIM, and 6.36, -14.03, 1.11, P = 17, for the right VIM. The PFA-VIM atlas overcomes several limitations of the current anatomical atlases and can improve targeting of thalamotomies and thalamic stimulations. It is dynamic and can easily be extended with new cases.

Intracranial retrograde dissemination in filum terminale myxopapillary ependymomas

Myxopapillary ependymomas (ME) are considered benign tumours (WHO grade I) of the central nervous system with long term survival rates and a tendency to local recurrence. However an aggressive course has occasionally been described, leading to CSF dissemination and even systemic metastases. We describe the case of a 23-year-old man diagnosed with intracranial subarachnoid dissemination of a filum terminale ME three years after the initial diagnosis. We have performed a careful review of the literature on CSF dissemination in ME and finally propose treatment of these cases.

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.

Endoscopic third ventriculostomy in a series of 36 adult patients

Endoscopic third ventriculostomy (ETV) has gained popularity and has become the treatment of choice for certain pediatric and adult hydrocephalic conditions. The authors report their experience with 36 adult patients and evaluate the long-term outcome and safety of ETV. They discuss several improvements to the surgical techniques that they have developed based on their experience, including the use of intraoperative Doppler imaging before fenestration to trace the location of vessels underlying the floor of the third ventricle. They also report the use of a Rickham reservoir and endoventricular stent in selected cases and discuss the indications for their use. In cases of obstructive hydrocephalus due to congenital or acquired aqueductal stenosis in adults, the success rate of ETV in avoidance of shunt placement is 72%. Twenty-two percent of the patients in this series in whom ETV was initially successful later experienced closure of the fenestration and recurrent symptoms at a mean interval of 3.75 years. Thus, in patients who undergo this treatment, long-term periodic follow-up review should be performed.

Neuroendoscopy: past, present, and future

Neuroendoscopy began with a desire to visualize the ventricles and deeper structures of the brain. Unfortunately, the technology available to early neuroendoscopists was not sufficient in most cases for these purposes. The unique perspective that neuroendoscopy offered was not fully realized until key technological advances made reliable and accurate visualization of the brain and ventricles possible. After this technology was incorporated into the device, neuroendoscopic procedures were rediscovered by neurosurgeons. Endoscopic third ventriculostomy and other related procedures are now commonly used to treat a wide array of neurosurgically managed conditions. A seemingly limitless number of neurosurgical applications await the endoscope. In the future, endoscopy is expected to become routine in modern neurosurgical practice and training.

Endoscopic third ventriculostomy

The traditional treatment for all forms of hydrocephalus has been the implantation of ventricular shunt systems; however, these systems have inherent tendencies toward complications such as malfunction and infection. A significant advance in the treatment of hydrocephalus has been the evolution of endoscopy. The recent technological advances in this field have led to a renewed interest in endoscopic third ventriculostomy as the treatment of choice for obstructive hydrocephalus. Although several different endoscopes are available, the authors favor a rigid one to perform a blunt fenestration of the third ventricle floor. This description of the technique stresses the nuances for successful completion of this procedure.

Endoscopic third ventriculostomy for tumor-related hydrocephalus in a pediatric population

OBJECT

Endoscopic third ventriculostomy (ETV) has become a common alternative for managing hydrocephalus in select patients. Nevertheless, there is still controversy regarding the indications for ETV as the primary procedure, given its variable success rates. The purpose of this study is to review the authors' experience with ETV for a variety of patients.

METHODS

A total of 43 children underwent ETV between July 1992 and June 2003. Their medical records, operative reports, and imaging studies, when available, were retrospectively reviewed with regard to outcome, complications, and patency rate. Treatment failure was defined as the need to place a shunt within 4 weeks of performing ETV in the patient. There were 20 male and 23 female patients with a mean age of 9.6 years (range 8 weeks-21 years). The overall success rate was 69.8%, and the mean follow-up duration was 24.6 months. Six patients underwent eight repeated ETVs at a mean interval of 25 months, with a patency rate of 62.5% after the second procedure. Only two surgeries were aborted for anatomical reasons. The highest success rates (100% in each instance) were achieved for obstructive hydrocephalus resulting from midbrain/tectal tumor (four patients) and pineal tumor (three patients).

CONCLUSIONS

The ETV procedure is an effective management tool for obstructive hydrocephalus in children. It should be considered the primary procedure, rather than ventriculoperitoneal shunts, in carefully selected children. The success rate is dependent on the origin of the hydrocephalus.

Retrospective analysis of 400 neuroendoscopic interventions: the Hungarian experience

Object

The authors present the results of 400 consecutive neuroendoscopic interventions performed by a single surgeon in 373 patients during the last 8 years.

Methods

The study is based on a retrospective analysis of a continuously updated electronic database that includes patient history and radiological files. The success rate of the interventions is calculated.

Conclusions

The underlying pathological condition was hydrocephalus of various origins. The success rate within patient groups is given and the factors leading to successful surgery are emphasized. Recommendations on indications for neuroendoscopic operations are discussed.

Functional analysis of third ventriculostomy patency by quantification of CSF stroke volume by using cine phase-contrast MR imaging

OBJECTIVE

Endoscopic third ventriculostomy (ETV) is increasingly used as alternative treatment for obstructive hydrocephalus. The aim of this study was to determine the utility of quantitative and qualitative examinations with cine phase-contrast MR imaging to determine the efficacy of ventriculostomy across time and whether CSF pulsation is restored after ETV.

METHODS

Thirty-eight patients treated with ETV were evaluated with cine phase-contrast MR within 1 month after surgery. Follow-up studies were performed after 1 year in 25 patients and after 2 years in 12. We evaluated flow void changes in the floor of the third ventricle and quantified the stroke volume at the site of the ventriculostomy. We also recorded changes in ventricular size and clinical outcome. To determine the restoration of CSF pulsation, we compared the CSF waveform at the ventriculostomy with the CSF waveform at the aqueduct in a healthy control group.

RESULTS

After ventriculostomy, restoration of pulsate motion characteristics of CSF circulation was observed. The stroke volume registered at ventriculostomy was maintained with time. There was a statistically significant relationship between clinical outcome and stroke volume. Overall flow magnitude was the most effective variable to determine which patients would improve after surgery. Values >75 mm3 showed a sensitivity of 76.7% and a specificity of 87.5% There was no relationship between ventricular size changes and clinical outcome. Patients with primary aqueduct stenosis had the best response to surgery, whereas patients with Arnold Chiari malformation or communicating hydrocephalus had the worst response.

CONCLUSION

Quantitative analysis with phase-contrast MR imaging indicates that ETV is an efficient technique for restoring CSF pulsation, with efficacy being maintained during the follow-up controls. Quantification of stroke volume at ventriculostomy is a good indicator of the functional status of ETV, and a high stroke volume in the ventriculostomy appears to be a positive predictor of favorable clinical outcome.

Intraventricular haemorrhage from a renal cell carcinoma pituitary metastasis

Symptomatic pituitary metastasis and intraventricular haemorrhage from a cerebral metastasis are exceptional events in the natural history of a renal cell carcinoma. We report the first case of a metastatic renal cell carcinoma to the pituitary gland presenting with intraventricular haemorrhage. The origin of intraventricular haemorrhage and its association with renal cell carcinoma pituitary metastasis are discussed.

Third ventricular cavernous haemangioma

We report a case of a third ventricular cavernous haemangioma (cavernoma). Cavernomas rarely occur within the ventricular system. Only 47 well-documented cases have been reported in the literature, 21 of which were located in the third ventricle. Cavernomas should be considered in the differential diagnosis of third ventricular lesions. Ventriculoscopy is very useful in establishing the diagnosis.

Spontaneous ventriculostomy in a patient with obstructive hydrocephalus

BACKGROUND

Spontaneous ventriculostomy related to progressive obstructive hydrocephalus is rare. Radiologic demonstration of such a phenomenon can be delineated with magnetic resonance imaging (MRI) and cine MRI.

CASE PRESENTATION

A 59-year-old woman with a known tectal glioma and symptoms of chronic hydrocephalus developed progressively worsening headaches. During follow-up, she noted spontaneous relief of her headaches. Follow-up cine MRI demonstrated a spontaneous ventriculostomy via the floor of the third ventricle.

INTERPRETATION

Clinicians should be aware of spontaneous ventriculostomy demonstrable on cine MRI because it may obviate the need for a CSF diversion procedure.

Endoscopic third ventriculostomy for chronic hydrocephalus after tuberculous meningitis

BACKGROUND

Cerebrospinal fluid diversion procedures are indicated in patients with hydrocephalus after tuberculous meningitis (TBM). We present 2 patients with hydrocephalus after TBM who were successfully treated with endoscopic third ventriculostomy (ETV).

METHODS

Two patients had been diagnosed with hydrocephalus after TBM and had undergone ventriculoperitoneal shunt surgery for the same. They presented with multiple episodes of shunt dysfunction. Endoscopic third ventriculostomy was performed (twice for one patient), and the patients were evaluated clinically and radiologically after the procedure.

RESULTS

On long-term clinical follow-up (3 and 2 years, respectively), both patients were asymptomatic after the ETV. The first patient was radiologically evaluated 7 months after the procedure and the second patient 2 years after the procedure. The first patient showed a decrease in ventricular size. The second patient did not show any significant change in the ventricular size.

CONCLUSION

Endoscopic third ventriculostomy can be considered as a safe and long-lasting solution for hydrocephalus after chronic TBM.

Characterization of brain plasticity in schizophrenia using template deformation

RATIONALE AND OBJECTIVE

Abnormal neurodevelopment may play a role in the pathophysiology of schizophrenia. We used deformation-based morphometry to examine voxel-wise age-related changes in patients with schizophrenia compared with healthy brains.

MATERIALS AND METHODS

We used a set of skull-stripped brains from an image database of cranial magnetic resonance images. We then deformed a template brain to the rest of the brains creating a set of deformation fields. Using the Jacobian values of these deformation fields, we calculated the voxel-wise t-score for comparison of controls with patients. We also calculated the voxel-wise Pearson correlation of Jacobian with age for both controls and patients.

RESULTS

By examining the volume renderings of these statistical fields, we found that healthy people undergo age-related expansion of the ventricles, the surrounding periventricular white matter, and a corresponding decline in the frontal lobes and cingulate gyrus. In contrast, patients show much less of this age-related expansion of the ventricles and less atrophy in the cerebral cortex. In addition, patients have larger ventricles and reduced volume in the frontal/parietal lobes.

CONCLUSION

These constellations of findings suggest that otherwise normal age-related ventricular enlargement and cortical loss occurs in schizophrenia patients, albeit at an earlier age.

[Complications and failures of endoscopic ventriculostomy of the third ventricle]

The study was undertaken to elucidate the poor outcomes of endoscopic ventriculostomy of the third ventricle (EVTV), including complications and dysfunctions. A series of 249 consecutive EVTV (the mean age of 15 years in 247 patients) made at the Institute of Neurosurgery in 1995 to 2003 was analyzed. The causes of hydrocephalus were benign tumors in 95 (38%) patients, stenosis of the aqueduct of the cerebrum in 73 (29%), malignant tumors in 63 (25%), and other causes in 18 (7%) cases. Obstruction in the posterior cranial fossa was present in 12 (5%); prior to EVTV, 24 (10%) and 36 (15%) patients had undergone craniotomy and bypass surgery, respectively; 12 (5%) patients had sustained subarachnoidal or intraventricular hemorrhage, 21 (8%) had intracranial infections. The follow-up averaged 16 months. Its results showed that 40 complications occurred in 34 (14%) patients. Seven (3%) patients required unplanned operations; transient and persistent neurological deficits were present in 15 (6%) and 2 (1%), respectively; there were no surgery-related deaths. Meningitis occurred in 14 (6%) cases; its risk was higher in patients having a history of intracranial infections (p = 0.02); meningitis was absent in patients with benign tumors (p < 0.01). Intracranial hemorrhages occurred in 7 (3%) cases; 2 of them required surgical treatment. Moreover, there were 6 (2%) wound complications (4 cases of wound cerebrospinal fluid discharge); 5 (2%) EVTVs were prematurely discontinued; isolated neurological deficit occurred in 6 (2%), single seizures were observed in 2 (1%). There were early dysfunctions in 16 (6%) cases; their risk was associated with obstruction in the posterior cranial fossa (p = 0.04) and with the technical result of an operation (p < 0.01). Late dysfunctions occurred in 21 (8%) cases, on the average, after 12 months of EVTV; their risk was higher in patients with malignant tumors (p = 0.04). It is concluded that indications for EVTV should be substantiated by the good chance of having a steady-state surgical success, by an overall prognosis, and staffs experience. The history of intracranial infections requires careful preoperative studies. Obstruction at the level of the posterior intracranial fossa is a relative contraindication to EVTV due to a low chance of having a success. The high risk for late dysfunctions in patients with malignant tumors requires a more strict choice of indications in this group. If there is anastomotic dysfunction, EVTV may be a good alternative to shunt revision.

Multilocated mature teratoma: a case report and review of the literature

Mature teratomas are rare inclusion tumors, which have benign behaviors. Different locations of the tumor were reported in the literature. However, multiple tumor locations are extremely rare. An eight year old patient presented with an intraventricularly mature teratoma. During the six year follow up-period, two separately located masses were observed in the chest area and in the right iliac region, and both tumors were histologically diagnosed as mature teratomas. In this study, this unique case of mature teratoma presented with multiple locations in three separate body compartments. Furthermore, intraventricular dissemination with sellar and parasellar extension was observed in the third ventricle.

Reactive gliosis in areas around third ventricle in association with epileptogenesis in amygdaloid-kindled rat

Repeated focal electrical stimulation of the brain is known to produce epileptogenesis, and this phenomenon is recognized as kindling. It is also considered to be a model of temporal lobe epilepsy. In the present study, morphological changes in areas around third ventricle in rat brain were examined according to the progression of kindling stage. Very few Glial Fibrillary Acidic Protein (GFAP)-positive astrocytes were present in ependymal cell layer at C0 stage. However, there was a specific increase in GFAP-positive cells in ependymal cell layer at stage C3 as compared to stage C0. Furthermore, GFAP-positive cells showed migration to subependymal zone (SEZ). By stage C5, almost all GFAP-positive cells had migrated to SEZ. While the precise mechanism of this cell migration is not clear, the results suggest a relationship between progression of kindling stage and astrogliosis.

Hypothesis about the physiopathology of acute deterioration and sudden death caused by colloid cysts of the third ventricle

In this paper, the authors review the mechanisms of acute deterioration and sudden death caused by colloid cysts (CCs). These dreaded events are widely recognized complications of CC, however the mechanism(s) in cause has been subject to controversy. Increased intracranial pressure (ICP) is a common event associated with many cerebral disorders, including colloid cysts, though compensatory mechanisms may allow ICP to remain at normal levels. However, a compensated system might decompensate for many factors such as intracranial haemorrhage, acute hydrocephalus, brain oedema, or an increase in sagittal sinus pressure (SSP). The sagittal sinus in adults with brain tumours appears to respond unpredictably when ICP increases and in some patients, when ICP increased the SSP increased too due to the fact that their sinuses collapse. We therefore speculate that the mechanism of acute deterioration and sudden death is a multifactorial and dynamic process, in which the increase in sagittal sinus pressure would appear to be an important element. It seems possible that acute deterioration is initiated by an increase in sagittal sinus pressure, which provokes acute brain swelling, with a series of often-irreversible events, leading to sudden death. Since the majority of cases of acute deterioration and death are due to CCs of the third ventricle, the authors suggest that surgical resection should be carried out on diagnosed CCs measuring over 1 cm, because sudden death has not been reported as having been caused by colloid cysts measuring less than this dimension.

Colloid cyst of the third ventricle: cytomorphologic features on stereotactic fine-needle aspiration

Stereotactic brain fine-needle aspiration (FNA) is a valuable diagnostic modality for evaluating space-occupying central nervous system disorders. Colloid cyst (CC) is a rare nonneoplastic lesion thought to arise from misplaced endodermal tissue in the anterosuperior portion of the third ventricle. This study summarizes cytomorphologic features of CC on FNA along with clinical, radiologic, and histopathologic correlation. Ten cases of CC of the third ventricle diagnosed on FNA were retrospectively reviewed for a period of 12 yr (1989-2000). Material was obtained under stereotactic radiologic guidance. Smears were stained with Diff-Quik and Papanicolaou stains and cell block sections with hematoxylin and eosin. The aspirates showed a characteristic sticky and viscous quality on gross examination. Smears showed abundant, amorphous, proteinaceous material with staining qualities similar to colloid aspirated from thyroid. This included a purplish, filmlike coating of the slide with occasional "cracking" artifact; thick, globular, eosinophilic fragments; and granular, ropelike, and somewhat viscous, mucinous material. Pathognomonic radiating hyphae-like structures were not seen. The cellular components varied from isolated cuboidal/columnar cells to large tissue fragments of glandular-type epithelium with focal ciliated border. Goblet cells were frequently identifiable, as were fragments of collagenous cyst wall. Stereotactic FNA of the CC of the third ventricle is an accurate and cost-effective diagnostic modality. Cytomorphology coupled with the radiologic features is sufficiently unique for the diagnosis of this rare pathologic entity.

Tissue resonance analysis; a novel method for noninvasive monitoring of intracranial pressure. Technical note

A number of noninvasive methods used to measure intracranial pressure (ICP) have been proposed in the literature. For a variety of reasons, however, none of these have displayed significant practical applicability. The authors describe their development of a new, computerized, portable device based on tissue resonance analysis (TRA) technology for the noninvasive monitoring and measurement of ICP. In response to the heart beat, the soft tissue and fluid compartments of the brain each exhibit characteristic vibration and mechanical resonant responses that radiate through the organs and tissues of the body. Patterns of vibration and mechanical resonance of various body organs and tissues are different and provide the possibility of extracting new and specific information in a noninvasive fashion. According to the TRA approach, ICP is dependent on the value of the dominant secondary (mechanical) resonance level of brain tissue. By digitally processing a reflected ultrasound signal (by using a concave ultrasonography probe with a carrier frequency of 1 MHz) from the third ventricle, the authors obtained a digital high-resolution echopulsogram, which visually is equivalent to ICP waves that are obtained invasively. The fast Fourier relationship of electrocardiogram and echopulsogram waves allowed the derivation of the secondary mechanical resonance levels. The authors developed a formula for a quantitative, noninvasive measurement of ICP, which uses information regarding multiple components of the intracranial space-both mechanical (secondary resonance) and physiological (time required for transfer of arterial blood to venous blood through brain tissue)-and the relationship between these components. A comparison of invasive and noninvasive ICP measurements was made during blinded trials in 40 patients with various diseases of the central nervous system, and ranges of ICP were measured from I to 66 mm Hg. The ICP values obtained using the two methods were highly correlated (r = 0.99), without a statistically significant difference between simultaneously obtained readings (p = 1). By using an integrative approach that reflects all components of the intracranial compartment, TRA allows for accurate noninvasive recordings of ICP. This method has significant advantages over other noninvasive technologies reported to date.

High risk of acute deterioration in patients harboring symptomatic colloid cysts of the third ventricle

OBJECT

Patients harboring colloid cysts of the third ventricle can present with acute neurological deterioration, or the first indication of the lesion may appear when the patient suddenly dies. The risk of such an occurrence in a patient already identified as harboring a colloid cyst is unknown. The goal of this study was to estimate the risk of acute deterioration in patients with colloid cysts.

METHODS

A retrospective study was made of a cohort of patients with newly diagnosed colloid cysts who were recruited in The Netherlands between January 1, 1993, and December 31, 1997. Seventy-eight patients were identified, all of whom displayed symptoms. Twenty-five patients (32%) presented with symptoms of acute deterioration; four patients died suddenly and the cysts were discovered at autopsy. The overall mortality rate was 12%. Results of a multivariate logistic regression analysis demonstrated that no subgroup of patients presenting without acute deterioration could be identified on the basis of patient age, duration of symptoms, cyst size, or the presence of hydrocephalus. The national incidence of colloid cysts in The Netherlands is 1/10(6) person-years; the prevalence was estimated to be 1800 asymptomatic colloid cysts.

CONCLUSIONS

Acute deterioration was a frequent presentation among a national cohort of Dutch patients harboring symptomatic colloid cysts. The risk of acute deterioration in a symptomatic patient with a colloid cyst in The Netherlands is estimated to be 34%. The estimated risk for an asymptomatic patient with an incidental colloid cyst is significantly lower. These results strongly advocate the selection of surgical treatment for patients with symptomatic colloid cysts.

Association of prolonged fever and hypernatremia: rare presentation of hypothalamic/third ventricle tumor in a toddler

The authors describe a 2-year-old boy with a clinical presentation of prolonged fever of unknown origin and severe hypernatremia. This rare association was the result of a hypothalamic/third ventricle tumor. The lesion was removed and was found to be a low-grade neuronal tumor. After surgery, the child did generally well, but hypothalamic thermoregulatory and osmoregulatory functions were not restored. These presenting symptoms, their pathophysiology, and the implications for pediatric practice are discussed.