A novel method for stereotactic, endoscope-assisted transtentorial placement of a shunt catheter into symptomatic posterior fossa cysts

Craniovertebral and spinal adhesive arachnoiditis: a late complication of ruptured vertebral and posterior inferior cerebellar arteries aneurysms

BACKGROUND

Adhesive arachnoiditis is a rare yet serious complication that may occur following subarachnoid hemorrhage (SAH). In this circumstance, it is mainly due to ruptured vertebral artery (VA) or posterior inferior artery (PICA) aneurysms. It disrupts cerebrospinal fluid (CSF) flow leading to complications such as spinal arachnoiditis, syringomyelia, trapped 4th ventricle, or a combination of these conditions. Evidence for effective treatment strategies is currently limited. We aimed to review the epidemiology, clinical characteristics, treatment, complications, outcomes, and prognosis of cranio-vertebral junction and spinal adhesive arachnoiditis resulting from ruptured VA and PICA aneurysms.

METHODS

This study involved a comprehensive literature review and complemented by our own case. We focused on adult cases of arachnoiditis, syringomyelia, and trapped 4th ventricle with SAH caused by ruptured VA or PICA aneurysms, excluding cases unrelated to these aneurysms and those with insufficient data.

RESULTS

The study included 22 patients, with a mean age of 52.4 years. Symptoms commonly manifest within the first year after SAH and timely diagnosis requires a high index of suspicion. Treatment approaches included lysis of adhesions and various shunt procedures. Most patients showed improvement post-treatment, though symptom recurrence is significant.

CONCLUSION

Adhesive arachnoiditis is a critical complication following SAH, most commonly from ruptured VA and PICA aneurysms. Early detection and individualized treatment based on the type of arachnoiditis and CSF flow impact are crucial for effective management. This study underscores the need for tailored treatment strategies and further research in this field.

Transcerebellar ventriculoperitoneal shunt for management of presumed arachnoid diverticulum in the fourth ventricle of a dog

OBJECTIVE

To describe the approach for placement of a transcerebellar fourth ventriculoperitoneal shunt for management of presumed fourth ventricle arachnoid diverticulum and secondary obstructive hydrocephalus of a dog. To describe the outcome of this procedure.

STUDY DESIGN

Case report.

ANIMALS

Male entire English springer spaniel, 3 years 9 months of age.

METHODS

The dog was initially presented for management of acute, progressive, and multifocal brainstem and forebrain dysfunction. Magnetic resonance imaging revealed internal obstructive hypertensive hydrocephalus. The dog was managed via ventriculoperitoneal shunting from the left lateral ventricle and made an excellent recovery. The dog acutely deteriorated 18 months after initial discharge and follow-up magnetic resonance imaging confirmed the ventricular shunt remained in situ with normal-sized lateral ventricles but revealed a cystlike lesion within the fourth ventricle, presumed to be a fourth ventricle arachnoid diverticulum. The diverticulum was causing mass effect and resultant compression of adjacent neuroparenchyma. A second ventriculoperitoneal shunt was subsequently placed into the fourth ventricle via the caudal cranial fossa and cerebellum. This was attached to a three-way connector, to which the existing shunt (within the left lateral ventricle) was also attached, and then secured to the existing medium-pressure valve.

RESULTS

Postoperatively, the dog immediately developed mild vestibular-cerebellar ataxia, with a marked improvement after 3 months. There were no shunt-associated complications. Long-term follow up at 40 months after the second surgical procedure revealed a normal neurological examination.

CONCLUSION

Transcerebellar ventriculoperitoneal shunt placement for treatment of a presumed fourth ventricle arachnoid diverticulum was performed and was associated with a favorable long-term outcome.

Surgical management of intracranial arachnoid cysts in pediatric patients: radiological and clinical outcome

OBJECTIVE

Congenital intracranial cysts account for a significant portion of intracranial lesions in the pediatric population. The efficiency of surgical treatment in a pediatric cohort with intracranial arachnoid cysts (ACs) at different locations regarding clinical symptoms and mass effect was evaluated.

METHODS

A retrospective study of all children who underwent surgical treatment of an intracranial AC during an 11-year period (2007-2018) was performed. Demographics, clinical symptoms, and radiological cyst size pre- and postoperatively, as well as the reoperation rate and possible treatment complications, were analyzed.

RESULTS

A total of 116 intracranial cysts at 8 different anatomical locations were surgically treated in 113 children (median age 5 years and 10 months) predominantly by endoscopic technique (84%). The complication rate was 3%, and the reoperation rate was 16%. Preoperative cyst enlargement was significantly more common in infants (p < 0.0001), as was the need for reoperation (p = 0.023). After a median radiological follow-up of 26 months, > 50% reduction of cyst volume was seen in 53 cysts (46%), and 47 cysts (40%) showed a 10%-50% reduction. Acute clinical symptoms improved: nausea and vomiting, accelerated head growth, and headaches improved at 100%, 92% and 89%, respectively. However, chronic symptoms responded less favorably after a median clinical follow-up of 26 months.

CONCLUSIONS

The strategy of predominantly endoscopic treatment with navigation planning is efficient to alleviate clinical symptoms and to significantly reduce the mass effect of pediatric intracranial cysts at different anatomical locations. The subgroup of infants requires close pre- and postoperative monitoring.

T-Connector Modification for Reducing Recurrent Distal Shunt Failure: Report of 2 Cases

BACKGROUND AND IMPORTANCE

Cerebrospinal fluid shunt placement is used to treat the various causes of hydrocephalus by redirecting the cerebrospinal fluid to the body, most commonly from the ventricle to the peritoneum. Distal catheter displacement from the peritoneal cavity can occur as a complication, necessitating reoperation.

CLINICAL PRESENTATION

We report 2 such cases in obese patients involving retropulsion of the distal tubing. To address this complication, we implanted a T-connector to the distal catheter construct.

CONCLUSION

This study supports the use of a T-connector catheter construct to decrease and prevent the possibility of distal peritoneal catheter retropulsion in cases of elevated intra-abdominal pressure, both prophylactically and in revisions.

Intra-catheter endoscopy for various shunting procedures-a retrospective analysis on surgical practicability, catheter placement, and failure rates

BACKGROUND

The long-term function of a cerebral shunt is directly influenced by the placement of the ventricle catheter. In this work, an intra-luminal endoscope for best possible catheter positioning was used. Practicability, postoperative imaging, and shunt failure rates were retrospectively evaluated.

METHODS

Between January 2012 and June 2016, an intra-catheter endoscope was applied in 71 procedures. Endoscopic technique was used for catheter placement in first-time shunting or cerebrospinal fluid reservoir insertion (n = 38), revision surgery in proximal shunt failure (n = 13), and various intraventricular stenting procedures (n = 20). Catheter positioning was graded on postoperative imaging using a four-point scale. All patients were regularly followed up (mean, 31.6 months) to recognize shunt failures.

RESULTS

Endoscopic application could be completed as intended in 68 of 71 procedures. Postoperative imaging could exclude complete misplacement of all catheters, but optimal positioning was only achieved in 64.7% (44/68 cases). Four catheters had to be revised due to malfunction (failure rate, 5.8%). Another five catheters had to be removed due to infectious complications or wound-healing disorders. Direct correlations between catheter complications and suboptimal catheter positioning were not seen. Slit or distorted ventricles also did not prove to be a risk factor for the observed complications.

CONCLUSIONS

Versatile application possibilities of the intra-catheter endoscope reflect the advantages of the technique. Independent of the performed procedure, unintended positionings or even complete catheter misplacements could be avoided. However, in more than one-third of all cases, suboptimal catheter placements became obvious. Interestingly, negative influences on later shunt failures were not seen.

Aqueductal stenting with an intra-catheter endoscope--a technical note

INTRODUCTION

Aqueductoplasty as well as aqueductal stenting is an accepted therapy option in short-segment aqueductal stenosis and isolated fourth ventricle. Over the years, different techniques with only slight modifications by using a conventional neuroendoscope with a working sheath to introduce different instruments have been presented. In summary, the use of Fogarty balloon catheters or flexible endoscopes to pass the narrowed aqueduct is recommended.

METHODS

This technical report describes a substantially new technique for this purpose. Six patients underwent aqueductal stenting with a new intracatheter endoscope.

RESULTS

Aqueductal stenting was possible in 4 out of 6 cases. No complications occurred. Handling of this new technique was good and easy without a prolonged learning curve. All four stents did work appropriately, and the procedure was considered to be successful. Of the two failures, the technique was abandoned and endoscopic third ventriculostomy (ETV) was performed in one. In the other case, suboccipital shunting was done.

CONCLUSION

This technical report describes a substantially new technique for aqueductal stenting. The combination of an intracatheter miniature endoscope and a prepared ventricular catheter enables careful and elegant aqueductal stenting. Large or flexible endoscopes, balloons, or special instruments to place a stent have become completely obsolete in selected cases.

Posterior fossa arachnoid cysts in adults: Surgical strategy: Case series

Introduction and Aim:

The management of posterior fossa arachnoid cyst (PFAC) in adults is controversial. To review our cases and literature, propose a practically useful surgical strategy, which gives excellent long-term outcome in management of PFAC.

Materials and Methods:

We analyzed our case records of 26 large intracranial arachnoid cysts in adults treated over 12 years. Of them, we had 7 patients with symptomatic PFAC. Reviewed the literature of 174 PFAC cases (1973–2012) and added 7 of our new cases with a follow-up ranging from 3 to 12 years.

Results:

In 6 cases the PFAC was located in the midline. In the 7^th case, it was located laterally in the cerebello-pontine (CP) angle. All patients were treated surgically. Excision of the cyst was performed in 5 of these cases. Among the two intra-fourth ventricular cysts, in both the cases cysto-peritoneal shunt was performed. Postoperative computed tomography/magnetic resonance imaging showed variable decrease in size of the cyst even though clinically all patients improved. We propose a surgical strategy for the management of these cases which would aid the surgeon in decision making.

Discussion:

We observed that these PFACs can occur either in the midline within the fourth ventricle or retroclival region or extra-fourth ventricular region. It can also develop laterally in the CP angle or behind the cerebellum or as intracerebellar cyst. Importance of this is except for Midline Intra-fourth ventricular cyst/retroclival cyst, the rest all can be safely excised with excellent long term outcome. The treatment strategy for Midline Intra-fourth ventricular cyst/retroclival cyst can be either cysto-peritoneal shunt or endoscopic fenestration of the cyst.

MRI characteristics of fourth ventricle arachnoid diverticula in five dogs

Intracranial arachnoid diverticula (cysts) are rare accumulations of cerebrospinal fluid (CSF) within the arachnoid membrane. The purpose of this retrospective study was to describe magnetic resonance imaging (MRI) characteristics of fourth ventricle arachnoid diverticula in a group of dogs. The hospital's medical records were searched for dogs with MRI studies of the brain and a diagnosis of fourth ventricle arachnoid diverticulum. Clinical characteristics were recorded from medical records and MRI studies were reinterpreted by a board-certified veterinary radiologist. Five pediatric dogs fulfilled inclusion criteria. Clinical signs included cervical hyperaesthesia, obtundation, tetraparesis, and/or central vestibular syndrome. In all five dogs, MRI findings were consistent with obstructive hydrocephalus, based on dilation of all ventricles and compression of the cerebellum and brainstem. All five dogs also had cervical syringohydromyelia, with T2-weighted hyperintensity of the gray matter of the cord adjacent to the syringohydromyelia. A signal void, interpreted as flow disturbance, was observed at the mesencephalic aqueduct in all dogs. Four dogs underwent surgical treatment with occipitalectomy and durotomy. A cystic lesion emerging from the fourth ventricle was detected in all four dogs during surgery and histopathology confirmed the diagnosis of arachnoid diverticula. Three dogs made excellent recovery but deteriorated shortly after surgery and were euthanized. Repeat MRI in two dogs revealed improved hydrocephalus but worsening of the syringohydromyelia. Findings from the current study supported theories that fourth ventricle arachnoid diverticula are secondary to partial obstruction of the central canal or lateral apertures and that arachnoid diverticula are developmental lesions in dogs.

Selective use of intra-catheter endoscopic-assisted ventricular catheter placement: indications and outcome

PURPOSE

In a previous well-controlled study, routine endoscopic-guided placement of ventricular catheters did not seem to decrease the rate of shunt failure or proximal shunt malfunction. Since this study was published, this technique does not seem to gain much acceptance. However, in selected cases, it may assist in accuracy and safety. We therefore have analyzed our experience with selective intra-catheter endoscopic use for ventricular hardware placement.

METHODS

We retrospectively collected clinical and radiological data on all children undergoing intra-catheter endoscopic-assisted ventricular catheter placement.

RESULTS

During 25 months, 16 children (ages 3 months-18 years) underwent 18 procedures using the above technique. Indications for surgery were: proximal shunt malfunction with relatively small ventricles (ten children), proximal shunt malfunction with intraventricular membranes (one child), proximal shunt malfunction with distorted ventricles (one child), new shunt with small to medium sized ventricles (two children), or large ventricles and a loculated fourth ventricle secondary to an aqueductal web (two children). Fourteen procedures were technically successful. The catheter was properly located on postoperative imaging in 13 procedures. Frameless navigation was used in three cases.

CONCLUSIONS

Selective use of intra-catheter endoscopic-assisted proximal shunt placement is useful and may be indicated in small or distorted ventricles and in cases when fenestration of an intraventricular membrane or aqueductal web is indicated. The main value of such a technique is the ability to accurately place the catheter tip within distorted or small ventricles. Larger series are needed to refine these indications.

Prenatal neurologic anomalies: sonographic diagnosis and treatment

The low prevalence of fetal CNS anomalies results in a restricted level of exposure to, and limited experience for most obstetricians involved in, prenatal ultrasound. Sonographic guidelines for screening the fetal brain in a systematic way may increase the detection rate of fetal CNS anomalies, thus promoting correct referral to tertiary care centers offering patients a multidisciplinary approach to the condition. The aim of this review is to elaborate on the prenatal sonographic diagnosis and outcome of various CNS malformations. Detailed neurosonographic investigation has become available through high-resolution vaginal ultrasound probes and the development of a variety of 3-dimensional (3D) ultrasound modalities, such as ultrasound tomographic imaging. In addition, fetal magnetic resonance imaging is particularly helpful in the detection of gyration and neurulation anomalies, and disorders of the gray and white matter. Isolated mild ventriculomegaly is a rather common finding with good overall outcome. With an increasing diameter of the atria, however, and especially with the presence of associated malformations, long-term neurodevelopmental and behavioral outcome is disturbed in about 15% or more of cases. In view of recent developments in fetal therapy for neural tube defects, there is a clear need for a high level of ultrasound screening, work-up and counseling in tertiary care centers to identify those cases that might benefit from in utero intervention. The failure of prosencephalic midline induction and development results in midline defects ranging from alobar holoprosencephaly to isolated corpus callosum defects. The detection of callosal abnormaties is enhanced by 3D ultrasound, but counseling on neurodevelopmental outcome remains challenging. The Dandy-Walker spectrum includes isolated megacisterna magna, Blake's pouch cyst, hypoplasia of the vermis and Dandy-Walker malformation. Except for complete agenesis of the vermis associated with fourth ventricle cyst formation, data on long-term outcomes for the various conditions is largely lacking. Congenital cytomegalovirus (CMV) results in the highest incidence of children born with, or developing, long-term neurologic conditions. If proof of fetal infection has been delivered, microcephaly, cortical malformations, and intraparenchymal cysts show a strong correlation with poor outcome. Fetuses with CMV-related ultrasound abnormalities might benefit from maternal transplacental treatment. The aneurysm of the vein of Galen, a vascular malformation of the brain, often results in high cardiac output failure. After neonatal arterial embolization, survival is about 50% with normal neurologic development in 36% of cases. Over 50% of intracranial tumors are teratomata, presenting as fast-growing heterogeneous solid-cystic masses with calcifications. Most intracranial hemorrhages are related to the ventricular system, and prognosis is often poor, particularly in cases involving parenchymal and subdural bleeding. Proliferation disorders of the brain are often characterized by microcephaly. Their etiology is heterogeneous and prenatal diagnosis is often made late in gestation.