Bilateral abducent and facial nerve palsies following fourth ventricle shunting: two case reports

Odd presentation of shunt malfunction: a case series and review of literature

OBJECTIVE

Children with previous ventriculoperitoneal shunt (VPS) insertion due to hydrocephalus may refer to the hospital with various clinical complaints. Shunt malfunction is frequently diagnosed in these children necessitating shunt revision. Although increased head circumference, setting sun eye in younger children, and headache, nausea/vomiting, loss of consciousness, visual disturbance, and other signs of intracranial hypertension are common clinical manifestations of shunt malfunction, some patients may present with odd or unusual symptoms. Here, we present a series of patients with shunted hydrocephalus who presented with odd and unexpected clinical manifestations of shunt malfunction.

METHODS

Eight children with shunt malfunction were enrolled in this series. The age, sex, age of shunting, etiology of hydrocephalus and management, post-shunt insertion symptoms/sign, revision surgery, outcome, and follow-up were evaluated.

RESULTS

Patients were aged from 1 to 13 years (mean, 6.38 years). There were 5 males and 3 females. The odd presentation associated with shunt malfunction included facial palsy in three children, ptosis in 3 children, and torticollis and dystonia each in one child. All patients underwent shunt revision except for one patient in whom a new shunt was inserted. Follow-up showed improvement of the symptoms in all patients.

CONCLUSION

In this series, we reported eight patients with unusual signs and symptoms following shunt malfunction that were successfully diagnosed and managed.

Clinical Outcome of Endoscopic Procedure in Patients with Shunt Malfunction

OBJECTIVE

The goal of this study was to analyze the clinical outcomes of endoscopic third ventriculostomy (ETV) and endoscopic septostomy when shunt malfunction occurs in a patient who has previously undergone placement of a ventriculoperitoneal shunt.

METHODS

From 2001 to 2020 at Seoul National University Children's Hospital, patients who underwent ETV or endoscopic septostomy for shunt malfunction were retrospectively analyzed. Initial diagnosis (etiology of hydrocephalus), age at first shunt insertion, age at endoscopic procedure, magnetic resonance or computed tomography image, subsequent shunting data, and follow-up period were included.

RESULTS

Thirty-six patients were included in this retrospective study. Twenty-nine patients, 18 males and 11 females, with shunt malfunction underwent ETV. At the time of shunting, the age ranged from 1 day to 15.4 years (mean, 2.4 years). The mean age at the time of ETV was 13.1 years (range, 0.7 to 29.6 years). Nineteen patients remained shunt revision free. The 5-year shunt revisionfree survival rate was 69% (95% confidence interval [CI], 0.54-0.88). Seven patients, three males and four females, with shunt malfunction underwent endoscopic septostomy. At the time of shunting, the age ranged from 0.2 to 12 years (mean, 3.9 years). The mean age at the time of endoscopic septostomy was 11.9 years (range, 0.5 to 29.5 years). Four patients remained free of shunt revision or addition. The 5-year shunt revision-free survival rate was 57% (95% CI, 0.3-1.0). There were no complications associated with the endoscopic procedures.

CONCLUSION

The results of our study demonstrate that ETV or endoscopic septostomy can be effective and safe in patients with shunt malfunction.

Trapped Fourth Ventricle: Pathophysiology, History and Treatment Strategies

Trapped fourth ventricle is a clinic-radiological entity characterised by progressive neurological symptoms due to enlargement and dilatation of fourth ventricle secondary to obstruction to its outflow. There are several causative mechanisms for the development of trapped fourth ventricle, including previous haemorrhage, infection or inflammatory processes. However, this condition is most commonly observed in ex preterm paediatric patients shunted for a post-haemorrhagic or post-infective hydrocephalus. Until the introduction of endoscopic aqueductoplasty and stent placement, treatment of trapped fourth ventricle was associated with high rates of reoperation and complications resulting in morbidity. With the advent of new endoscopic techniques, supratentorial and infratentorial approaches for aqueductoplasty and stent insertion have revolutionised the treatment of trapped fourth ventricle. Fourth ventricular fenestration and direct shunting remain viable options in cases where aqueduct anatomy and length of obstruction is not surgically favourable for endoscopic approaches. In this book chapter, we explore the background, historical developments,$ and surgical treatment strategies in the management of this challenging condition.

The entity of the trapped fourth ventricle: A review of its history, pathophysiology, and treatment options

An isolated or trapped fourth ventricle is a relatively rare, although serious, adverse effect of hemorrhagic, infectious, or inflammatory processes that involve the central nervous system. This entity usually occurs after successful shunting of the lateral ventricles and may become clinically evident with the development of delayed clinical deterioration. This decline of the neurological status of the patient is evident after an initial period of improvement of the relevant symptoms. Surgical treatment options include cerebrospinal fluid shunting procedures, along with open surgical and endoscopic approaches. Complications related to its management are common and are related with obstruction of the fourth ventricular catheter, along with cranial nerve or brainstem dysfunction. We used the keywords: "isolated fourth ventricle," and "trapped fourth ventricle," in PubMed^® and Web of Science^®. Treatment of the trapped fourth ventricle remains a surgical challenge, although the neurosurgical treatment armamentarium has broadened. However, prompt recognition of the clinical and neurological findings that accompany any individual patient, in conjunction with the relevant imaging findings, is mandatory to organize our treatment plan on an individual basis. The current experience suggests that any individual intervention plan should be mainly based on the underlying pathological substrate of hydrocephalus. This could help us to preserve the patient's life, on an emergent basis, as well as to ensure an uneventful neurological outcome, maintaining at least the preexisting level of neurological function.

Endoscopic antegrade aqueductoplasty and stenting with panventricular catheter in management of trapped fourth ventricle in patients with inadequately functioning supratentorial shunt

Background:

Trapped fourth ventricle (TFV) usually develops as a complication of supratentorial ventricular CSF shunting, especially when hydrocephalus is caused by intraventricular hemorrhage and/or infection. This study aimed to assess the feasibility of endoscopic aqueduct stenting using a single refashioned shunt tube to treat cases presenting with both TFV and shunt malfunction.

Methods:

We retrospectively collected and analyzed data from patients presenting with TFV and supratentorial shunt malfunction who underwent endoscopic aqueduct stenting using a refashioned shunt tube. All cases were treated at our institution between January 2010 and July 2019. The surgical technique is described.

Results:

Eighteen patients were enrolled in our study. There were ten males and eight females. The mean age was 11.2 years (range = 1–33 years). Headache, nausea, and vomiting were the most common clinical presentations. The mean duration of follow-up was 22.1 months (range = 6–60 months). All cases showed clinical and radiological improvement after surgery.

Conclusion:

Endoscopic antegrade aqueductoplasty and stenting with the refashioned panventricular shunt catheter are an adequate treatment option for both TFV and supratentorial shunt malfuncion.

Endoscopic Fourth Ventriculostomy: Suboccipital Transaqueductal Approach for Fenestration of Isolated Fourth Ventricle: Case Report and Technical Note

BACKGROUND

Trapped or isolated fourth ventricle is a known, late sequela after lateral ventricular shunt placement for hydrocephalus, particularly after infection or hemorrhage. It may cause brainstem compression and insidiously present with ataxia, dysarthria, and intracranial hypertension, further delaying diagnosis. There is no universally agreed on treatment algorithm, and options include open fenestration through a suboccipital craniotomy, fourth ventricle shunting, and minimally invasive options including endoscopic stenting and fenestration through a precoronal approach.

CASE DESCRIPTION

We describe a young child with epilepsy and symptomatic brainstem compression from a dilated fourth ventricle, with a history of streptococcal parietal abscess and posthemorrhagic hydrocephalus requiring shunt placement. Given his history of infection and nearly neurologically intact examination, we pursued minimally invasive endoscopy through a suboccipital, transaqueductal approach to fenestrate his fourth ventricle.

CONCLUSIONS

Magnetic resonance imaging (MRI) demonstrated complex, loculated hydrocephalus and a dilated fourth ventricle. Under electromagnetic navigation, we endoscopically fenestrated his fourth ventricle using a rarely described suboccipital, transaqueductal approach. He tolerated the procedure without complication and improved neurologically, although his follow-up MRI demonstrated no change in fourth ventricular dilation at 1 year. Although there was no decrease in size of the fourth ventricle on follow-up MRI, we describe an alternative, well-tolerated, suboccipital approach for the management of a trapped fourth ventricle. Fenestration of a web of tissue in the aqueduct of Sylvius provided long-term clinical improvement and may provide a rescue approach for patients who are not candidates for standard approaches.

Reversible Progressive Multiple Cranial Nerve Paresis in the Isolated Fourth Ventricle following Placement of Fourth Ventricle Shunt: Case Report and Review of the Literature

BACKGROUND/AIMS

Multiple lower cranial nerve paresis occurring after placement of a fourth ventricle shunt for an isolated fourth ventricle is an uncommon complication in the postoperative period. Of the various etiologies, direct brain stem injury by the catheter and rapid decompression of the fourth ventricle by the shunt causing traction on the cranial nerves have been reported in the literature.

METHODS

We report the case of a 9-year-old girl with an isolated fourth ventricle who developed bilateral facial and multiple lower cranial nerve paresis with bilateral internuclear ophthalmoplegia a month after placement of a ventriculoperitoneal shunt. The postprocedure MRI showed a well-decompressed fourth ventricle with catheter tip located along the long axis of the fourth ventricle.

RESULTS

She was managed non-operatively. She improved gradually in her cranial nerve paresis over the next 3 months and completely recovered at 9 months.

CONCLUSION

We believe the reversible multiple cranial nerve neuropathies resulted from acute decompression of the fourth ventricle following the shunt insertion. A gradual decompression of the dilated fourth ventricle by an aqueductal stent or a high-pressure shunting system could prevent this potential complication.

Transtentorial Distortion Syndrome: Consistent Complication Following Lateral and Fourth Ventricular Shunting in Adults

BACKGROUND

Complex hydrocephalus affecting lateral and fourth ventricles separately is occasionally managed with cerebrospinal fluid diversion via supratentorial and infratentorial ventricular catheters. The optimal configuration to reduce complications is currently unknown in adults. We describe a consistently similar clinical presentation of patients with complex hydrocephalus and a fourth ventricle separately drained by infratentorial shunt insertion.

METHODS

This was a retrospective single-center case series. Medical notes were reviewed for clinical presentation, brain imaging, and neurophysiologic tests results. All patients underwent intracranial pressure monitoring (ICPM). Outcomes were determined by ventricular appearance on brain imaging computed tomography and symptomatic improvements postoperatively.

RESULTS

Five adult patients referred to the hydrocephalus service had separate infratentorial and supratentorial shunt systems. A common clinical presentation was observed, including lower motor neuron facial palsy (confirmed with electrophysiology), ophthalmoplegia, dysarthria, impaired gait headache, and nausea. We refer to this as transtentorial distortion syndrome. Twenty-four-hour ICPM demonstrated clear low pressures. All patients underwent shunt revision connecting the transtentorial shunts via a Y-connector and the addition of a distal valve. All subjects had improved ventricular appearance on computed tomography scans post revision, and normalization of ICPM was observed. In the follow-up period of 6 months, no patient required further shunt revision.

CONCLUSION

To prevent transtentorial distortion syndrome, supratentorial and infratentorial shunt constructs in adults with encysted fourth ventricles should be similar to the shunt systems widely known in the pediatric population with Dandy-Walker syndrome (i.e., joint output to a single valve distal to the connection of the 2 proximal drainage catheters).

Cranial nerve palsies after shunting of an isolated fourth ventricle

An isolated fourth ventricle is characterised by cerebrospinal fluid (CSF) trapping in the fourth ventricle. Although there is no consensus regarding treatment, ventriculoperitoneal (VP) shunting of the fourth ventricle is an option. Complications include infection, mechanical irritation of the brainstem, malfunction and overdrainage. Cranial nerve palsy is a rare complication and has been mostly described in children. We present two adult cases of abducens and facial nerve palsies occurring secondary to this procedure. Placement of a higher resistance valve brought about complete recovery in one patient while withdrawal of the catheter by a few millimetres led to complete recovery in the second patient.

Endoscopic transaqueductal or interventricular stent placement for the treatment of isolated fourth ventricle and pre-isolated fourth ventricle

OBJECT

The aim of our study is to evaluate the effectiveness of endoscopic transaqueductal or interventricular stent placement into the fourth ventricle for isolated fourth ventricle (IFV) and pre-isolated fourth ventricle (PIFV), in which occlusion of the fourth ventricle outlets and dilation of the fourth ventricle are seen while the aqueduct is still patent.

METHODS

We retrospectively analyzed pediatric patients who underwent endoscopic stent placement for IFV or PIFV.

RESULTS

Five patients with IFV and four patients with PIFV underwent endoscopic stent placement. The mean age was 11.5 months. Three patients with IFV underwent aqueductoplasty with stent connected to an extracranial shunt system. Two patients with IFV and supratentorially protruded fourth ventricle underwent interventriculostomy with stent. In these patients, the stent was not connected to the shunt system as functional shunt had been already placed using the contralateral ventricle. In four patients with PIFV, transaqueductal stent was placed and connected to the extracranial shunt system. In all patients, preoperative symptoms improved and magnetic resonance imaging demonstrated reduction of the size of the fourth ventricle. The mean follow-up period was 49.6 months (range 5 to 99 months). Three patients (33 %) underwent reoperation due to obstruction of the abdominal catheter, partial occlusion of the ventricular catheter, and retraction of the fourth ventricular catheter.

CONCLUSION

The endoscopic transaqueductal or interventricular stent placement into the fourth ventricle for the treatment of IFV is considered to be effective and safe. The transaqueductal stent placement for PIFV is also considered to be effective for resolution of symptoms and prevent progression into IFV.

Cranio-cervical decompression and expansile duroplasty for isolated fourth ventricle in a patient with Chiari II malformation

The management of isolated fourth ventricle in Chiari II malformation remains a complex challenge. Commonly accepted treatment options have been associated with high rates of complications and failure. Cranio-cervical decompression and autologous expansile duroplasty may be an effective primary intervention for this condition.

Neuroendoscopic treatment of multiloculated hydrocephalus in children

OBJECT

The authors performed a retrospective analysis of data obtained in a series of 30 patients suffering from multiloculated hydrocephalus and treated endoscopically. The goal of the study was to evaluate the effectiveness of neuroendoscopic treatment as an alternative to the placement of multiple shunts to relieve intracranial hypertension, to simplify the shunt system, and to reduce the high rate of shunt revision.

METHODS

The endoscopic procedures included intraventricular septum fenestration, aqueductoplasty, Monro foraminoplasty, and third ventriculostomy. The patients were divided into two groups: Group A included 23 children in whom a shunt was already in place at the time of endoscopy, and Group B included seven children in whom a shunt had never been placed. The control of hydrocephalus by a single shunt placement or the absence of a shunt was achieved in 25 (83.3%) of 30 children. In Group A, five children no longer had shunts, 14 needed a single shunt, three required two shunts, and one required three shunts. The mean preendoscopy shunt revision rate in this group decreased from 2.07/year to 0.35/ year following the endoscopic procedure. Seven patients required endoscopic reoperations (endoscopic reoperation rate 0.31/year, total reoperation rate [shunt revisions plus endoscopic reoperation] 0.66/year). In Group B, three children did not require shunts, three needed a single shunt, and one required two shunts. Two patients required repeated endoscopic surgery (endoscopic reoperation rate 0.19/year), and two patients required shunt revisions (shunt revision rate 0.07/year) (total operation rate 0.26/year).

CONCLUSIONS

Neuroendoscopic procedures are a valid alternative to shunt revision in the management of multiloculated hydrocephalus. Early diagnosis comprising close monitoring with high-resolution magnetic resonance imaging and early treatment are the keys of success.

Facial nerve palsy-an unusual complication after evacuation of a subdural haematoma or hygroma in children

OBJECTIVE

This paper reports and discusses on the possible etiology of postoperative contralateral facial nerve palsy after uneventful evacuation of a subdural haematoma or hygroma after mild head trauma in two children with pre-existing middle cranial fossa subarachnoid cysts.

RESULTS

Two 14- and 15-year-old boys had prolonged headaches after mild head injuries. CT showed a right-sided middle cranial fossa arachnoid cyst in each patient. In one patient, an ipsilateral subdural haematoma was identified, and in the other, bilateral hygromas were identified. Exacerbation of symptoms required emergency evacuation of the subdural haematoma in the first child, and bilateral external drainage of the hygroma in the other child. In both children the late postoperative period was complicated by peripheral facial nerve palsies contralateral to the arachnoid cyst.

CONCLUSION

Facial nerve palsy may be a complication of hygroma or haematoma drainage. The etiology is not clear; traction of the facial nerve due to displacement of the brainstem may be the most likely explanation.

Endoscopic aqueductoplasty and placement of a stent in the cerebral aqueduct in the management of isolated fourth ventricle in children

OBJECT

In this study the authors conducted a retrospective evaluation of the effectiveness of endoscopic aqueductoplasty, performed alone or accompanied by placement of a stent, in the treatment of an isolated fourth ventricle (IFV) in seven patients afflicted with loculated hydrocephalus after a hemorrhage or infection.

METHODS

Seven children with symptomatic IFV and membranous aqueductal stenosis underwent endoscopic aqueductoplasty alone or combined with placement of a stent in the cerebral aqueduct. The mean age of the patients at the time of surgery was 10 months. The mean duration of follow up was 26 months. In all patients a supratentorial shunt had already been implanted, and in five patients neuroendoscopy had already been performed because other isolated compartments had been present inside the ventricular system. Aqueductoplasty alone was performed in three patients and aqueductoplasty and aqueductal stent placement in four. A precoronal approach was performed in five patients and a suboccipital approach in two. Signs and symptoms of intracranial hypertension resolved in all cases. Stent placement was successful in all five cases, resulting in clinical and neuroimaging-confirmed improvements in the IFV. Restenosis of the aqueduct occurred in two patients in whom stents had not been placed. In one of these patients restenosis was managed by an endoscopic procedure, during which the aqueduct was reopened and a stent implanted; in the other patient a shunt was placed in the fourth ventricle. Hydrocephalus was controlled by a single shunt in six cases (86%) and by a double shunt in one case.

CONCLUSIONS

Endoscopic placement of a stent in the aqueduct is more effective in preventing the repeated occlusion of the aqueduct than aqueductoplasty alone and should be indicated as the initial treatment in each case of compatible anatomy.