The Dandy-Walker syndrome: diagnostic and surgical considerations

The Management of Hydrocephalus in Midline Posterior Fossa Cystic Collections: Surgical Outcome From a Retrospective Single-Center Case Series of 54 Consecutive Pediatric Patients

BACKGROUND

Hydrocephalus frequently occurs with midline posterior fossa cystic collections. The classification of this heterogeneous group of developmental anomalies, including Dandy-Walker malformation, persisting Blake's pouch, retrocerebellar arachnoid cysts, and mega cisterna magna, is subject of debate. The absence of diagnostic criteria is confusing regarding the ideal management of PFCC-related hydrocephalus.

OBJECTIVE

To decipher the surgical strategy for the treatment of children with PFCC-related hydrocephalus through a retrospective analysis of the surgical outcome driven by their clinical and radiological presentation.

METHODS

This study enrolled patients operated of symptomatic PFCC-related hydrocephalus. Clinical and MRI features were examined, as well as the surgical outcome. Unbiased subgroup classification of the patients was performed with multiple component analysis as a function of imaging characteristics and hierarchical clustering on principal component. Outcome was assessed with binomial logistic regression and Kaplan-Meier analysis.

RESULTS

Fifty-four patients were included between 2007 and 2021. Multiple component analysis suggested that cerebellar and vermian hypoplasia, vermian rotation, basal-tentorial angle, and fastigial angle were strongly correlated. Hierarchical clustering and the distribution of the patients in the bidimensional plot showed the clear segregation of 3 major clusters, which correlated with the radiological diagnosis ( P < .01). Binomial logistic regression and survival analysis showed that endoscopic third ventriculostomy was an effective treatment for patients with persisting Blake's pouch, while failing to control hydrocephalus in most of patients with Dandy-Walker malformation.

CONCLUSION

Preoperative MRI in patients with PFCC-related hydrocephalus is essential to better define the diagnosis. The choice of treatment strategy notably relies on correct radiological diagnosis.

Craniomegaly in Neonate and Infants Requiring Neurosurgical Intervention: An Experience at Tertiary Care Center

Background The identification of neurosurgical causes of craniomegaly and early institution of therapy requires for better clinical and functional outcomes.

Aims and Objectives The aim of this study was to evaluate the neurosurgical causes, managements, and outcomes of craniomegaly in neonate and infants.

Materials and Methods The cases with a history of head enlargement from neonatal period were included in this study. Their causes, managements, and outcomes were recorded retrospectively during the period of January 2010 to February 2013, in neurosurgery department at SGPGIMS Lucknow, and June 2018 to June 2020, at UPUMS, Saifai, Etawah, UP, India.

Results Out of 41 cases, there were 30 (73.14%) cases of hydrocephalus, 4 (9.76%) Dandy-Walker malformation, 2 (4.88%) subdural collection, 2 (4.88%) arachnoid cyst, 1 (2.44%) craniosynostosis, and 2 (4.88%) with tubercular meningitis. The age range of our cases was 18 to 178 days and the mean age was 102.54 ± 50.73. Preoperative head circumference range was 39 to 62 cm (mean: 55.27 ± 6.58cm). Majority of the cases (n = 32, 78.05%) were managed with ventriculoperitoneal shunt surgeries. Out of 41 cases, 33(80.49%) had improved outcomes, 7 (17.07%) stabilized, and mortality occurred in 1 (2.44%) case. Postoperatively, there was improvement in the head circumference (range: 39–60 cm and mean: 46.15 ± 5.83 cm) on 6 to 24 months (mean: 17.85 ± 5.18 months) of follow-up.

Conclusion Hydrocephalus was the commonest neurosurgical cause of head enlargement in neonate and infants. Shunt surgery was the most common form of management of these cases. Early detection, institution of therapy, and periodic follow-up program for diagnosing and treating complications were the key to successful outcomes in these patients.

Neuroimaging of Dandy-Walker malformation: new concepts

Dandy-Walker malformation (DWM) is the most common human cerebellar malformation, characterized by hypoplasia of the cerebellar vermis, cystic dilation of the fourth ventricle, and an enlarged posterior fossa with upward displacement of the lateral sinuses, tentorium, and torcular. Although its pathogenesis is not completely understood, there are several genetic loci related to DWM as well as syndromic malformations and congenital infections. Dandy-Walker malformation is associated with other central nervous system abnormalities, including dysgenesis of corpus callosum, ectopic brain tissue, holoprosencephaly, and neural tube defects. Hydrocephalus plays an important role in the development of symptoms and neurological outcome in patients with DWM, and the aim of surgical treatment is usually the control of hydrocephalus and the posterior fossa cyst. Imaging modalities, especially magnetic resonance imaging, are crucial for the diagnosis of DWM and distinguishing this disorder from other cystic posterior fossa lesions. Persistent Blake's cyst is seen as a retrocerebellar fluid collection with cerebrospinal fluid signal intensity and a median line communication with the fourth ventricle, commonly associated with hydrocephalus. Mega cisterna magna presents as an extraaxial fluid collection posteroinferior to an intact cerebellum. Retrocerebellar arachnoid cysts frequently compress the cerebellar hemispheres and the fourth ventricle. Patients with DWM show an enlarged posterior fossa filled with a cystic structure that communicates freely with the fourth ventricle and hypoplastic vermis. Comprehension of hindbrain embryology is of utmost importance for understanding the cerebellar malformations, including DWM, and other related entities.

Hydrocephalus in Dandy-Walker malformation

INTRODUCTION

Even if the first description of Dandy-Walker dates back 1887, difficulty in the establishment of correct diagnosis, especially concerning differential diagnosis with other types of posterior fossa CSF collection, still persists. Further confusion is added by the inclusion, in some classification, of different malformations with different prognosis and therapeutic strategy under the same label of "Dandy-Walker".

METHODS

An extensive literature review concerning embryologic, etiologic, pathogenetic, clinical and neuroradiological aspects has been performed. Therapeutic options, prognosis and intellectual outcome are also reviewed.

CONCLUSION

The correct interpretation of the modern neuroradiologic techniques, including CSF flow MR imaging, may help in identifying a "real" Dandy-Walker malformation. Among therapeutical strategies, single shunting (ventriculo-peritoneal or cyst-peritoneal shunts) appears effective in the control of both ventricle and cyst size. Endoscopic third ventriculostomy may be considered an acceptable alternative, especially in older children, with the aim to reduce the shunt-related problems. Prognosis and intellectual outcome mostly depend on the presence of associated malformations, the degree of vermian malformation and the adequate control of hydrocephalus.

Management of Dandy-Walker complex-associated infant hydrocephalus by combined endoscopic third ventriculostomy and choroid plexus cauterization

OBJECT

Dandy-Walker complex (DWC) is a continuum of congenital anomalies comprising Dandy-Walker malformation (DWM), Dandy-Walker variant (DWV), Blake pouch cyst, and mega cisterna magna (MCM). Hydrocephalus is variably associated with each of these, and DWC-associated hydrocephalus has mostly been treated by shunting, often with 2-compartment shunting. There are few reports of management by endoscopic third ventriculostomy (ETV). This study is the largest series of DWC or DWM-associated hydrocephalus treated by ETV, and the first report of treatment by combined ETV and choroid plexus cauterization (ETV/CPC) in young infants with this association.

METHODS

A retrospective review of the CURE Children's Hospital of Uganda clinical database between 2004 and 2010 identified 45 patients with DWC confirmed by CT scanning (25 with DWM, 17 with DWV, and 3 with MCM) who were treated for hydrocephalus by ETV/CPC. Three were excluded because of other potential causes of hydrocephalus (2 postinfectious and 1 posthemorrhagic).

RESULTS

The median age at treatment was 5 months (88% of patients were younger than 12 months). There was a 2.4:1 male predominance among patients with DWV. An ETV/CPC (ETV only in one) was successful with no further operations in 74% (mean and median follow-up 24.2 and 20 months, respectively [range 6-65 months]). The rate of success was 74% for DWM, 73% for DWV, and 100% for MCM; 95% had an open aqueduct, and none required posterior fossa shunting.

CONCLUSIONS

Endoscopic treatment of DWC-associated hydrocephalus should be strongly considered as the primary management in place of the historical standard of creating shunt dependence.

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

OBJECT

Posterior fossa cysts are usually divided into Dandy-Walker malformations, arachnoid cysts, and isolated and/or trapped fourth ventricles. Shunt placement is a mainstay treatment for decompression of these fluid collections when their expansion becomes symptomatic. Although several techniques to drain symptomatic posterior fossa cysts have been described, each method carries its own advantages and disadvantages. This article describes an alternative technique.

METHODS

In 10 patients, the authors used an alternative technique involving stereotactic and endoscopic methods to place a catheter in symptomatic posterior fossa cysts across the tentorium. Discussion of these cases is included, along with a review of various approaches to shunt placement in this region and recommendations regarding the proposed technique.

RESULTS

No patient suffered intracranial hemorrhage related to the procedure and catheter implantation. All 3 patients who underwent placement of a new transtentorial cystoperitoneal shunt and a new ventriculoperitoneal shunt did not suffer any postoperative complication; a decrease in the size of their posterior fossa cysts was evident on CT scans obtained during the 1st postoperative day. Follow-up CT scans demonstrated either stable findings or further interval decrease in the size of their cysts. In 1 patient, the postoperative head CT demonstrated that the transtentorial catheter terminated posterior to the right parietal occipital region without entering the retrocerebellar cyst. This patient underwent a repeat operation for proximal shunt revision, resulting in an acceptable catheter implantation. The patient in Case 8 suffered from a shunt infection and subsequently underwent hardware removal and aqueductoplasty with stent placement. The patient in Case 9 demonstrated a slight increase in fourth ventricle size and was returned to the operating room. Exploration revealed a kink in the tubing connecting the distal limb of the Y connector to the valve. The Y connector was replaced with a T connector, and 1 week later, CT scans exhibited interval decompression of the ventricles. This patient later presented with cranial wound breakdown and an exposed shunt. His shunt hardware was removed and he was treated with antibiotics. He later underwent reimplantation of a lateral ventricular and transtentorial shunt and suffered no other complications during a 3-year follow-up period.

CONCLUSIONS

The introduction of endoscopic and stereotactic techniques has expanded the available treatment possibilities for posterior fossa cysts.

Treatment options for Dandy-Walker malformation

OBJECT

The aim of this study was to assess the efficacy of various treatment options available for children with Dandy-Walker malformation (DWM) and to evaluate the role of endoscopic procedures in the treatment of this disorder.

METHODS

The authors conducted a retrospective review of 72 children who underwent surgical treatment for DWM during a 16-year period. All patients underwent computed tomography scanning, and 26 underwent magnetic resonance (MR) imaging. The initial surgical treatment included ventriculoperitoneal (VP) shunt placement in 21 patients, cystoperitoneal (CP) shunt placement in 24, and combined VP and CP shunt insertion in three. Twenty-one patients underwent endoscopic procedures (endoscopic third ventriculostomy [ETV] alone in 16 patients, ETV with aqueductal stent placement in three, and ETV with fenestration of the occluding membrane in two). Three patients underwent membrane excision via a posterior fossa craniectomy. In the 26 patients who had undergone preoperative MR imaging, aqueductal patency was noted in 23 and aqueductal obstruction in three. These three patients underwent placement of a stent from the third ventricle to the posterior fossa cyst in addition to the ETV procedure. During the follow-up period, 12 patients with a CP shunt and four with a VP shunt experienced shunt malfunctions that required revision. Four patients with a CP shunt also required placement of a VP shunt. In addition, five of the 21 ETVs failed, requiring VP shunt insertion. A reduction in ventricle size noted on postoperative images occurred more frequently in patients with a VP shunt, whereas a reduction in cyst size was more appreciable in patients with a CP shunt. Successful ETV resulted in a slight decrease in ventricle size and varying degrees of reduction in cyst size.

CONCLUSIONS

Endoscopic procedures may be considered an acceptable alternative in children with DWM. The authors propose a treatment protocol based on preoperative MR imaging findings of associated aqueductal stenosis.

Endoscopic, single-catheter treatment of Dandy-Walker syndrome hydrocephalus: technical case report and review of treatment options

Optimal treatment for hydrocephalus related to Dandy-Walker syndrome (DWS) remains elusive. Patients with DWS-related hydrocephalus often require combinations of shunting systems to effectively drain both the supratentorial ventricles and posterior fossa cyst. We describe an endoscopic technique, whereby a frontally placed, single-catheter shunting system effectively drained the supratentorial and infratentorial compartments. This reduces the complexity and potential risk associated with the combined shunting systems required by so many with DWS-related hydrocephalus.

Endoscopic third ventriculostomy with cystoventricular stent placement in the management of dandy-walker malformation: technical case report of three patients

OBJECTIVE AND IMPORTANCE

Dandy-Walker malformation has conventionally been managed with placement of cystoperitoneal or ventriculoperitoneal shunts. However, associated aqueductal obstruction requires simultaneous drainage of both the supratentorial and infratentorial compartments.

CLINICAL PRESENTATION

Three children with Dandy-Walker malformation and aqueductal obstruction were managed with endoscopic third ventriculostomy and placement of a stent from the third ventricle to the posterior fossa cyst.

INTERVENTION

After an endoscopic third ventriculostomy was performed, the stent was placed from the third ventricle to the posterior fossa cyst through the thinnest part of the posteroinferior wall of the aqueduct. There was no operative morbidity. In one patient, the stent was malpositioned, requiring a repositioning. The endoscopic third ventriculostomy was successful in two patients, whereas it failed in one, requiring a ventriculoperitoneal shunt placement.

CONCLUSION

Cystoventricular stent placement with endoscopic third ventriculostomy is a promising alternative in patients with Dandy-Walker malformation with aqueductal obstruction.

Dandy-walker malformation: prenatal diagnosis and outcome

Prenatal ultrasound identified Dandy-Walker malformation (DWM) in ten singleton pregnancies with concurrent central nervous system (CNS) anomalies and extra-CNS anomalies in eight cases. DWM was confirmed by postnatal magnetic resonance imaging (MRI) or pathological examination in nine cases. Karyotypes were normal in the seven infants tested. Postnatal neurological and developmental testing in the five survivors showed a spectrum of clinical outcome from minor defects to severe handicap. Postnatal investigation also disclosed additional CNS and extra-CNS findings not detected on ultrasound, as did autopsy in the other five infants. However, ultrasound diagnosis of DWM is accurate and is an indication for exhaustive screening for concurrent anomalies both within and outside the CNS and in chromosome structure and number, as the prognosis is heavily dependent on associated malformations and karyotype.

Bilateral optic atrophy with hydrocephalus

Images

Dandy-Walker syndrome presenting as opisthotonus: proposed pathophysiology

A patient with radiographically confirmed Dandy-Walker syndrome who presented with opisthotonus, a rarely reported clinical manifestation, is reported. From four separate pharmacologic trials (baclofen, diazepam, levodopa/carbidopa, and trihexyphenidyl), combination baclofen and diazepam therapy was determined to be most efficacious. Opisthotonus and extensor posturing remain only rudimentarily understood. We review the subject and propose a specific mechanism relating our patient's anatomic and physiologic conditions.

Brainstem tethering in Dandy-Walker syndrome: a complication of cystoperitoneal shunting. Case report

Treatment of the Dandy-Walker syndrome has included placement of a ventriculoperitoneal shunt alone or in combination with a posterior fossa cystoperitoneal shunt. Complications in shunting are common and are usually related to malfunction or infection. The authors present a case in which the patient developed headaches and focal cranial nerve deficits following infection caused by a cystoperitoneal shunt. Magnetic resonance imaging showed tethering of the brainstem. A posterior fossa craniotomy with microsurgical untethering and cyst fenestration achieved two goals: improvement of the focal cranial nerve deficits and elimination of the cystoperitoneal shunt.

Adult-onset presentation of Dandy-Walker variant in siblings

BACKGROUND

The Dandy-Walker syndrome and Dandy-Walker variant usually present as isolated cases of hydrocephalus in pediatric patients.

METHODS AND RESULTS

THis paper consists of a case report of the adult onset of symptoms in two sisters having Dandy-Walker variant. Such an occurrence has never before been reported in the medical literature. Both patients presented with headaches and progressive neurologic deficit. On computed tomography (CT scan) of the head, both were found to have hydrocephalus, with hypoplasia of the inferior vermis. Both patients were treated successfully with ventriculoperitoneal shunting. A third sister, with a similar history, elected not to undergo CT scanning or surgical treatment.

CONCLUSIONS

Variants of the Dandy-Walker syndrome may occasionally present clinically in the adult age group. Such an occurrence in siblings is consistent with an underlying genetic etiology.