Endoscopic observation of pathophysiology of ventricular diverticulum

Third ventricular diverticulum of the suprapineal recess can be a rare and confounding complication of chronic hydrocephalus: A case report with 2-year follow-up

PURPOSE

Chronic hydrocephalus is rarely seen in developed countries due to the widespread availability of CT scans for diagnosis and early treatment. In developing countries, it is more frequently encountered along with its rare complication of diverticulum formation.

METHODS

We report a case of a previously healthy 6 year old girl who presented with a 10 day history of headache, 3 day history of drowsiness and a single episode of generalized tonic clonic seizures. We review the literature on such cases and include imagining studies at follow up.

RESULTS

A CT scan done outside our hospital had been reported to be demonstrating a posterior fossa arachnoid cyst with resultant obstructive hydrocephalus. We first placed an external ventricular drain and performed an MRI of the brain to further characterize the lesion. It was again reported as an arachnoid cyst but on further scrutiny it was appreciated that it was in fact a third ventricular diverticulum of the suprapineal recess. She underwent ventriculoperitoneal shunt placement which led to resolution of the hydrocephalus as well as the diverticulum.

CONCLUSION

These diverticulae develop secondary to ventricular rupture in the setting of chronic untreated hydrocephalus. This pathology was first described in 1940 and over the years its identification has decreased due to a much lower incidence of chronic untreated hydrocephalus.

A Case of Spontaneous Third Ventriculocisternostomy to the Interpeduncular Fossa

BACKGROUND

Triventricular hydrocephalus is caused by an obstruction of cerebrospinal fluid flow causing increased intracranial pressure (ICP). Common treatment options include ventricular shunting or endoscopic third ventriculocisternostomy. Spontaneous third ventriculocisternostomy is a rare phenomenon in patients with obstructive triventricular hydrocephalus. We present the case of a patient with triventricular hydrocephalus and evidence of spontaneous third ventriculocisternostomy.

CASE DESCRIPTION

A 33-year-old female patient was referred to our outpatient clinic for triventricular hydrocephalus diagnosed on imaging. Magnetic resonance imaging (MRI) of her brain showed a triventricular obstructive hydrocephalus owing to a possible aqueductal stenosis. No clinical or diagnostic signs of elevated ICP were present. Repeat imaging showed no changes in cerebral ventricular size and MRI flow imaging demonstrated flow voids in the third ventricle extending through the floor of the third ventricle to the prepontine cistern. We concluded that the cause of hydrocephalus was likely to be a compensated aqueductal stenosis.

CONCLUSIONS

Spontaneous third ventriculocisternostomy is seen in patients with chronic hydrocephalus. MRI sensitive to flow artefacts can be useful in the diagnosis of patients with apparent compensated hydrocephalus, and phase-contrast imaging can prove cerebrospinal fluid flow across the stoma. Resolution of symptoms owing to elevated ICP is regularly observed in patients with a spontaneous ventriculocisternostomy.

Spontaneous third ventriculostomy 8 years after diagnosis of obstructive hydrocephalus

BACKGROUND

Spontaneous ventriculostomy is spontaneous rupture of membranes separating the ventricular system from the subarachnoid space in patients with chronic obstructive hydrocephalus that ends with resolution of symptoms. We present a case of spontaneous third ventriculostomy occurred in a 19-year-old girl 8 years after the initial diagnosis of hydrocephalus.

CASE DESCRIPTION

An 11-year-old girl applied to the clinic with intermittent headaches. She was neurologically stable with no visual problems. On her brain MRI, obstructive hydrocephalus was observed. Cerebrospinal fluid diversion procedures were recommended, yet the family denied any interventional procedure. She had routine follow-ups with occasional clinical admissions because of ongoing intermittent headaches. On her last clinical visit, 8 years after the first one, she was in well condition with improvement in her headache in the last 4 months. Her new brain MRI showed an active CSF flow between the basal cistern and the third ventricle.

DISCUSSION AND CONCLUSION

In patients with aqueductal stenosis and without any other mass lesion, wait and see protocol might be conveyed in case of mild symptoms of hydrocephalus. However, there is need for large-scaled studies to make a more comprehensive statement for benign obstructive hydrocephalus cases.

Intraparenchymal ventricular diverticula in chronic obstructive hydrocephalus: prevalence, imaging features and evolution

BACKGROUND

Intraparenchymal cavities communicating with the ventricles may appear in patients with chronic obstructive hydrocephalus despite no identifiable surgerical, vascular or traumatic causes. The rate, features, pathogenesis, evolution and clinical impact of intraparenchymal diverticula have not been outlined, yet.

METHODS

Brain MRIs of 130 patients (mean age: 11.3 years; age range: 0-67; 60 females) with chronic obstructive hydrocephalus were analyzed. The pathogenesis, neurosurgical treatment, ventricle size, signs of transependymal reabsorption and septum pellucidum integrity of the hydrocephalus were recorded. Subarachnoid outpouching of the ventricles, post-hemorrhagic parenchymal cavities, paths of ventricular shunting and cavities not communicating with the ventricles were excluded. Of patients with intraparenchymal diverticula, all previous available CT and MRI scans were evaluated.

RESULTS

Eight patients (6.2 %, mean age: 18.7 years; age range: 2-42) harbored 11 intraparenchymal diverticula sprouting from the temporal (6), occipital (3) or frontal (2) horns of the lateral ventricles. Intraparenchymal diverticula were more frequent in males (p = 0.04) and older patients (18.7 ± 12.7 vs 11.3 ± 9.8 years, p = 0.04). Their presence or evolution (mean neuroradiological follow-up 3.6 years; range: 0-8) showed a trend of association with hydrocephalus severity (bifrontal index) and did not correlate with the surgical treatment. In three patients the diverticula progressed during follow-up. One patient presented with hemiparesis consistent with the intraparenchymal lesion and improved after ventricular shunting. A DTI study revealed that the cortico-spinal tract was partly included in the septum between the ventricle and the intraparenchymal diverticulum.

CONCLUSIONS

Clinicians dealing with chronic severe obstructive hydrocephalus should be aware of ventricular intraparenchymal diverticulation. Studies aiming at clarifying their pathogenesis and proper management are warranted.

Neuroendoscopy Followed by Radiotherapy in Cystic Craniopharyngiomas--a Long-Term Follow-Up

BACKGROUND

Treatment of cystic craniopharyngiomas is often complicated because of adherence of craniopharyngiomas to adjacent brain structures. A strategy involving neuroendoscopic procedures followed by stereotactic radiotherapy is less invasive, avoiding brain damage. However, long-term follow-up of this strategy has not been investigated in depth.

METHODS

Cystic craniopharyngiomas in 9 patients were treated with neuroendoscopic cyst aspiration and fenestration, followed by fractionated stereotactic radiotherapy (FSRT). The neuroendoscopic procedure focused on widening of cyst fenestration and extensive irrigation of the cyst contents. FSRT was performed using 6 fixed beams, an 8-mm margin to cover the gross tumor volume with a 95% isodose line, and a target delivered dose of 50.4 Gy in 28 fractions.

RESULTS

The median follow-up period was 72.9 months. Tumor control was achieved in 8 of 9 patients (88.9%). Marked tumor volume reduction was obtained with the neuroendoscopic procedure alone (26.1%) at 6 months (20.4%), 1 year (11.0%), and 2 years (3.1%). One recurrent case showed multilobulated cysts, and a second surgery was required 1 year after the treatment. Clinical symptoms such as headache and visual disruption were rapidly alleviated after the neuroendoscopic procedure. No new visual disturbances, endocrinopathy, or hypothalamic dysfunction was observed during follow up.

CONCLUSIONS

Neuroendoscopic cyst aspiration and fenestration followed by FSRT is a less invasive, powerful strategy for treating adult cystic craniopharyngiomas.

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.

Relocation of ventricular catheter trough ventriculostomy due to congenital unilateral hydrocephalus: Nine year follow-up

Background:

Congenital unilateral hydrocephalus is an uncommon entity occurring almost exclusively in children. Atresia, stenosis, membranous occlusion and even functional obstruction of the foramen of Monro have been described to be the main cause of this type of hydrocephalus. There are two options available in the surgical management of unilateral hydrocephalus: one is the placement of shunt CSF diversion from the dilated ventricle and the other is fenestration of the occluded foramen of Monro or septum pellucidum by endoscopy or by stereotactic method. Migration of the ventriculoperitoneal (VP) shunt in or out of ventricles is not so uncommon, but the relocation of the ventricular tip of a catheter from the ventricle into the quadrigeminal cisterns and superior vermis in association with ventriculostomy is extremely rare. Spontaneous ventriculostomy is a rare event and results from spontaneous rupture of a ventricle into the subarachnoid space.

Case Description:

A 5½-month-old baby with a right-sided congenital unilateral hydrocephalus underwent a VP shunt andhad experienced an uneventful outcome. Four years later on an MR imaging examination, the tip of the ventricular catheter passing through the medial wall of the ventricle and the quadrigeminal cistern was found to be situated in the superior vermis. During the follow-up period, there were no neurological difficulties. The cognitive and motor skill development corresponded well with the child's age. It transpired that the hydrocephalic ventricle reduced its size dramatically to normal.

Conclusion:

We have described the extremely rare site of the relocation of the ventricular catheter after the treatment of the congenital unilateral hydrocephalus by VP shunting. Spontaneous ventriculostomy as a rare phenomenon may be the explanation of the relocation of the ventricular catheter.

Spontaneous third ventriculostomy: definition by endoscopy and cerebrospinal fluid dynamics

Chronic obstructive hydrocephalus is known to cause ventricular diverticula and, rarely, spontaneous ventriculostomy. The authors present the case of a patient in whom a spontaneous third ventriculostomy was identified with long-standing hydrocephalus secondary to aqueductal stenosis. To their knowledge, this is the first report in which a spontaneous stoma in the floor of the third ventricle was evaluated using endoscopy and cerebrospinal fluid dynamics studies. Both studies confirmed that the spontaneous stoma is similar in structure and function to surgical third ventriculostomy.