Changes in cerebral perfusion hormone profile and cerebrospinal fluid flow across the third ventriculostomy after endoscopic third ventriculostomy in patients with aqueductal stenosis: a prospective study. Clinical article

Thyroid Hormones and Health-Related Quality of Life in Normal Pressure Hydrocephalus Patients before and after the Ventriculoperitoneal Shunt Surgery: A Longitudinal Study

Objective: The aim of this study was to explore the serum levels of thyroid-stimulating hormone (TSH), free thyroxine (FT4), and free triiodothyronine (FT3), and to correlate the hormone levels among iNPH patients with their self-reported quality of life before and three months after the surgery. Methods: Twenty-five patients (52% women), mean age 63.5 (SD 9.5) years, were operated on by inserting a VP shunt. Patients with FT3 level ≤3.34 pmol/L were diagnosed as having low T3 syndrome. Results: The changes in thyroid hormones resulted in a U-shaped curve throughout the follow-up period. The significant changes occurred the next day after the surgery, including a decrease in TSH, FT3, and an increase in FT4. Additionally, the decrease occurred in mean FT3 for six patients with preoperative low T3 syndrome. Three months after the surgery, thyroid hormones were restored to their baseline and/or normal values. All six patients with preoperative low T3 syndrome had significant improvement in all SF-36 subscales (except for the role emotional and physical). Patients with preoperative normal high FT3 and low FT4 had increased FT3/FT4 ratio which was associated with deterioration in all SF-36 subscales 3 months after the surgery. Conclusion: Routine assessment of the FT3/FT4 ratio might be a simple and effective tool for the risk stratification of iNPH patients before VP shunt surgery.

Iodine-123-Iomazenil SPECT Revealed Recovery of Neuronal Viability in Association with Improvement in Symptoms Following Treatment for Obstructive Hydrocephalus due to a Giant Posterior Cerebral Artery Aneurysm

BACKGROUND

Early and late images of ¹²³I-iomazenil (¹²³I-IMZ) single-photon emission computed tomography (SPECT) are considered to show cerebral blood flow and neuronal activity, respectively, and this modality may demonstrate temporal dysfunction of the frontal lobes in obstructive hydrocephalus. In this report, we examined ¹²³I-IMZ SPECT in a patient with chronic obstructive hydrocephalus owing to compression of the aqueduct by a partially thrombosed aneurysm of the left posterior cerebral artery for the first time.

CASE DESCRIPTION

A woman aged 77 years presented with progression of cognitive decline, gait disturbance, and urinary incontinence. She had a medical history of epilepsy and subarachnoid hemorrhage due to a ruptured left posterior cerebral artery aneurysm, treated conservatively when she was age 56 years. Magnetic resonance imaging revealed a mass lesion in the pineal region, which showed a target sign with gadolinium-based contrast agents, causing obstructive hydrocephalus owing to compression of the cerebral aqueduct. A right vertebral angiogram confirmed the presence of a partially thrombosed giant aneurysm at the left posterior cerebral artery. To rule out the involvement of nonconvulsive status epilepticus in her pathology, we performed ¹²³I-IMZ SPECT, and both early and late images demonstrated low uptake in the bilateral frontal cortex. After surgical trapping of the parent artery and resection of the aneurysm, hydrocephalus was relieved, and the symptoms disappeared along with improvement in early and late ¹²³I-IMZ SPECT images.

CONCLUSIONS

The findings in the present case indicate that ¹²³I-IMZ SPECT can detect reversible cerebral blood flow reduction and neuronal viability in the frontal lobes, which may affect the clinical manifestation of obstructive hydrocephalus.

Amenorrhea after Endoscopic Third Ventriculostomy for a Failed Shunt in Spina Bifida: Case Report and Review of the Literature

BACKGROUND

Secondary endoscopic third ventriculostomy (ETV) for the management of shunt failure may be efficacious, though it may be followed by more frequent complications (including endocrinological impairment, e.g., amenorrhea) compared to primary ETV. These complications are usually underreported in the literature.

AIM

We report a case of secondary amenorrhea after ETV for the management of shunt failure in a young woman with hydrocephalus associated with myelomeningocele.

METHODS

A 25-year-old woman affected by hydrocephalus and myelomeningocele was admitted for secondary ETV for the management of shunt failure. The endoscopic procedure was preferred over shunt revision based on good results of secondary ETV, especially in patients with hydrocephalus associated with Chiari II malformation and spina bifida.

RESULTS

Despite the surgery being uneventful, the patient had early (postoperative seizure) and late (secondary amenorrhea) complications. In the early postoperative period, she received external ventricular drainage followed by VP shunt reimplantation 2 weeks later. There was no neurological morbidity, but 1 month after the ETV she reported secondary amenorrhea and weight gain. Laboratory investigations ruled out hyperprolactinemia, which had been treated with cabergoline administration with no efficacy since the patient was still without regular periods 1 year later.

CONCLUSION

ETV may be followed by endocrinological complications like amenorrhea that are rarely reported.

Ventricular endoscopy in the pediatric population: review of indications

INTRODUCTION

Neuroendoscopy has greatly impacted pediatric neurosurgery over the past few decades. Improved optics and microsurgical tools have allowed neuroendoscopes to be used for a multitude of neurosurgical procedures.

DISCUSSION

In this review article, we present the breadth of intraventricular neuroendoscopic procedures for the treatment of conditions ranging from hydrocephalus and brain tumors to congenital cysts and other pathologies. We critically discuss treatment indications and reported success rates for neuroendoscopic procedures. We also present novel approaches, technical nuances, and variations from recently published literature and as practiced in the authors' institution.

Radiological findings in relation to the neurodevelopmental outcome in hydrocephalic children treated with shunt insertion or endoscopic third ventriculostomy

PURPOSE

The aim of the study was to compare the radiological indicators of effectiveness for hydrocephalus treatment in children operated on under the third year of age with the use of shunt insertion (SI) and endoscopic third ventriculostomy (ETV). The effectiveness was considered in terms of postoperative neurodevelopment in correlation to pre- and postoperative radiological findings.

METHODS

The examined group consisted of 46 children operated on for hydrocephalus in the Division of Pediatric Neurosurgery in Katowice, Poland. There were 21 children treated with SI and 25 with ETV. The radiographic assessment was carried out on the basis of MRI and CT examinations with the use of a linear estimate known as frontal and occipital horn ratio (FOR). The FOR values were calculated for the entire group and in correlation to the treatment method and to the children neurodevelopment evaluated with The Denver Developmental Screening Test.

RESULTS

No differences were recognized between initial FOR value in terms of the postoperative children neurodevelopment. In the successful ETV-treated subgroup, the mean change in FOR was 0.05 and in the SI-treated subgroup, the mean change in FOR 0.13. The patients with BFOR >0.1, developed normally more often than those in whom BFOR was lower than 0.1.

CONCLUSIONS

The initial FOR value probably does not affect the postoperative developmental outcome. Long-term change in ventricles size after surgery can correlate with psychomotor development of hydrocephalic children. Presumably, there are no differences between two treatment options according to initial FOR values and to changes in FOR values.

Endoscopic 3rd ventriculocisternostomy: procedural complications and long-term dysfunctions?

BACKGROUND AND PURPOSE

The endoscopic third ventriculostomy (ETV) has become the treatment of choice for managing non-communicating hydrocephalus. The aim of this study was to evaluate the efficacy and the morbi-mortality of this procedure and its long-term outcome.

PATIENTS AND METHODS

This retrospective study involved 82 consecutive patients treated for non-communicating hydrocephalus by ETV, in a single centre, between June 1999 and November 2008. The main criterion of efficacy was clinical improvement with shunt independence. The secondary criteria were the ventricular size (third and lateral ventricles) outcome and the procedural morbidity and mortality. In order to determine the predictive factors of dysfunction, a uni- and multivariate analysis was conducted.

RESULTS

Divided in two groups, the overall success rate was 65.4% in the paediatric group (n=26) and 83.9% in the adult group (n=56), after respectively a mean follow-up of 59.1±36.7 and 49.3±27.7 months. A procedural complication occurred in 5 patients (6.1%), with no procedure-related death. The predictive factors of ETV failure were an infectious aetiology and an age less than 16. Changes in ventricular size and success rate were independent.

CONCLUSIONS

ETV is an effective procedure at long-term for the management of non-communicating hydrocephalus with low morbidity. Therefore, it should be considered as first-line treatment. Cerebrospinal meningitis infection and young age both expose patients to possible dysfunction.

Application of phase-contrast cine magnetic resonance imaging in endoscopic aqueductoplasty

The aim of this study was to evaluate the application of phase-contrast cine magnetic resonance imaging (MRI) in endoscopic aqueductoplasty (EA) for patients with obstructive hydrocephalus. The clinical diagnosis of hydrocephalus caused by aqueduct obstruction in 23 patients was confirmed by phase-contrast cine MRI examination. The patients were treated with EA and MRI was repeated during the follow-up. The cerebrospinal fluid (CSF) flow velocity in the aqueduct was measured to determine whether the aqueduct was obstructed. The results of phase-contrast cine MRI examinations indicated that there was no CSF flow in the aqueduct for all patients prior to surgery. Aqueductoplasty was successfully performed in all patients. The results of phase-contrast cine MRI examinations performed a week after surgery demonstrated an average CSF flow velocity of 4.74±1.77 cm/sec. During the follow-up, intracranial hypertension recurred in two patients in whom CSF flow was not observed in the aqueduct by the phase-contrast cine MRI scan. Aqueduct re-occlusion was revealed by an endoscopic exploration. By measuring the CSF flow velocity, phase-contrast cine MRI accurately identifies aqueduct obstruction. Cine MRI is a nontraumatic, simple and reliable method for determining whether the aqueduct is successfully opened following aqueductoplasty.

Adjustment of the endoscopic third ventriculostomy entry point based on the anatomical relationship between coronal and sagittal sutures

Object

The coronal suture is often used as an empirical landmark for the entry point for endoscopic third ventriculostomy. The trajectory for the approach is often drawn based on midsagittal MRI findings. However, because the coronal suture is not perpendicular to the midline, this method may be inaccurate.

Methods

The junction of the coronal and sagittal sutures was exposed at the outer table of the cranium of 15 cadavers. An ideal coronal line was established perpendicular to the sagittal suture at the junction of the sagittal and coronal sutures. The distance from this ideal coronal line at the level of the coronal-sagittal junction to the actual coronal suture was measured at 1-cm intervals. The measured distance between the 2 planes was termed the distance to the coronal suture.

Results

The coronal suture bows forward as it moves from medial to lateral. From 1–6 cm lateral to the sagittal suture, the distance to the coronal suture was 0.1, 0.3, 0.5, 0.8, 1.0, and 1.4 cm, respectively. There was no significant difference between the right and left sides.

Conclusions

The position of a bur hole for endoscopic third ventriculostomy should be moved posteriorly with respect to the coronal suture the more laterally it is placed. Although the adjustment is small, it may be crucial. Failure to make this adjustment may result in suboptimal bur hole placement and increase the risk of morbidity.

Amenorrhea complicating endoscopic third ventriculostomy in the pediatric age group

Endoscopic third ventriculostomy (ETV) is an accepted option in the treatment of obstructive hydrocephalus in children and is considered by many pediatric neurosurgeons to be the treatment of choice in this population. The procedure involves perforation of the floor of the third ventricle, specifically, the tuber cinereum, which is part of the hypothalamic-pituitary axis of cerebral endocrine regulation. Endocrine dysfunction, such as amenorrhea, weight gain, and precocious puberty, which are recognized only months to years after the procedure, may be underreported because patients and physicians may not relate the endocrine sequelae to the ETV. Few detailed reports of endocrine-related complications following ETV exist to better understand these issues. In this study, the authors add to the literature with case descriptions of and correlative laboratory findings in 2 adolescent girls who underwent ETV for obstructive hydrocephalus and in whom amenorrhea subsequently developed.

Endoscopic transventricular third ventriculostomy through the lamina terminalis

Object

Endoscopic third ventriculostomy (ETV) has become a well-accepted option for obstructive hydrocephalus. However, standard ventriculostomy at the floor of the third ventricle might not be feasible under certain conditions. Here, the authors report in detail on their initial experience with an alternative option of endoscopic ventriculostomy through the lamina terminalis via a transventricular route.

Methods

Endoscopic third ventriculostomy through the lamina terminalis from a transventricular transforaminal route was evaluated in 4 cadaveric human heads and in 4 clinical cases.

Results

In all 4 human cadavers, an opening of the lamina terminalis via a transventricular approach could be achieved without injury to either the optic chiasm or the anterior cerebral arteries. In the 4 clinical cases, an accurate and reliable ventriculostomy was performed at the lamina terminalis. The bur hole was placed directly at the coronal suture 2 cm lateral from the midline. After identifying the optic chiasm and the anterior cerebral arteries, a blunt perforation was made just anterior to the optic chiasm by using perforation forceps and a balloon catheter. After the opening, the stoma was inspected with a 0° and 30° rod lens endoscope, and its patency as well as the preservation of vessels and optic nerves was checked. No complications occurred, although all patients suffered from a clinically silent fornical contusion at the foramen of Monro.

Conclusions

Endoscopic opening of the lamina terminalis via a transventricular transforaminal route appears to be feasible. No complications were observed. Although no conclusions on the clinical success rate can be drawn, the reliable anatomical opening and known success rate for anterior subfrontal approaches suggest that the technique represents an alternative in a small subgroup of patients in whom a standard ETV cannot be performed.

Minimally invasive neurosurgery for cerebrospinal fluid disorders

This article focuses on minimally invasive approaches used to address disorders of cerebrospinal fluid (CSF) circulation. The author covers the primary CSF disorders that are amenable to minimally invasive treatment, including aqueductal stenosis, fourth ventricular outlet obstruction (including Chiari malformation), isolated lateral ventricle, isolated fourth ventricle, multiloculated hydrocephalus, arachnoid cysts, and tumors that block CSF flow. General approaches to evaluating disorders of CSF circulation, including detailed imaging studies, are discussed. Approaches to minimally invasive management of such disorders are described in general, and for each specific entity. For each procedure, indications, surgical technique, and known outcomes are detailed. Specific complications as well as strategies for their avoidance and management are addressed. Lastly, future directions and the need for structured outcome studies are discussed.