Dandy-Walker variant: a diagnosis by clinical and CT evaluation in a tertiary hospital in Nepal

<p class="abstract">Dandy-Walker variant (DWV) has been used to describe a combination of cystic dilation of the fourth ventricle and hypoplastic cerebellar vermis in the absence of an enlargement of the posterior fossa. Magnetic resonance imaging (MRI) is the modality of choice for diagnosing DWV. But it can also be diagnosed by evaluating the subject clinically and by CT scans. We presented here a case report of a patient with DWV who was diagnosed by clinical evaluation and CT scans. A 15 years old girl presented with the symptoms of pain and ear discharge from both ears. She had developmental delay, mental retardation and poor nutritional status. The CT scan of the patient showed a posterior fossa cyst with hypoplastic vermis and communicating hydrocephalus without obvious enlargement of the posterior fossa. Hence, a diagnosis of DWV was made. For the ear pathology, she underwent modified radical mastoidectomy and other medical treatments.</p>

Posterior Fossa Cyst and Hydrocephalus

A Dandy-Walker malformation is an anatomical triad characterized by a large posterior fossa, agenesis of the cerebellar vermis, and dilation of the 4th ventricle. Up to 90% of patients will have hydrocephalus secondary to obstruction of fourth ventricular outflow through the foramen of Luschka and Magendie. The differential diagnosis of Dandy-Walker malformation includes Blake’s pouch cyst, a cystic structure originating within the roof of the 4th ventricle that herniates into the cisterna magna, and posterior fossa arachnoid cysts, which typically displace both the cerebellum and 4th ventricle anteriorly and demonstrate a propensity to enlarge. Brain MRI is the best diagnostic imaging modality to evaluate posterior fossa anatomy and cystic structures. Not all posterior fossa cysts require treatment. Indications for surgical intervention include enlargement, symptomatic mass effect and/or hydrocephalus.

Endoscopic Management of Arachnoid Cysts

Object: Arachnoid cysts are developmental space-occupying lesions filled with CSF-like content and surrounded by a membrane resembling arachnoid mater, with controversial etiology and natural history. Endoscopy has been successfully used for decades to treat a variety of pathologies within thecentral nervous system. Methods: Thirteen patients who underwent endoscopic fenestration for treatment of arachnoid cyst were selected for this study. The surgical indications and techniques were reviewed, and surgical success rates and patient outcomes were assessed. Results: Five patients had middle fossa cysts; 2 a posterior fossa cyst; 3 a quadrigeminal cistern arachnoid cyst and 3 a suprasellar arachnoid cyst. Endoscopic management consisted in a cystoventriculostomy in 8 patients and cystocisternotomy in 5 patients. There was neither mortality nor operative morbidity. Discussion: Arachnoid cysts are a relatively benign pathological entity that can be managed by performing endoscopically guided cyst wall fenestrations into the ventricular system or cerebrospinal fluid containing cisterns. Conclusion: Proper patient selection, preoperative planning of endoscope trajectory, use of frameless navigation, and advances in endoscope lens technology and light intensitycombine to make this a safe procedure with excellent outcomes.

Early ultrasound prenatal diagnosis of the Meckel — Gruber syndrome in combination with 47,XYY

Meckel — Gruber syndrome (MGS) is a rare lethal autosomal recessive disorder characterised by occipital encephalocele, polydactyly and bilateral dysplastic cystic kidneys. A case of prenatal diagnosis of MGS at 12 weeks of gestation is described. The previous pregnancy was terminated at 20 weeks due to polycystic kidneys of the fetus. The transabdominal scan of the present pregnancy revealed occipital encephalocele of the fetus. There was no oligohydramnios, but the fetal urinary bladder was not visualised and both kidneys were enlarged. The transvaginal sonogram demonstrated intracranial space dilatation (6 mm) and encepalocele with posterior fossa cyst, protrunding from the occipital bone deffect. The kidneys had the polycystic structure suggesting cystic dysplasia and there was no evidence of the hands and feet polydactyly. Based on these findings the diagnosis of the MGS was made. Chorionic villus sampling revealed 47,XYY. The family elected to terminate pregnancy and the diagnosis was confirmed by autopsy.

A Case Study on Dandy Walker Syndrome: Early Intervention and Rehabilitation

Dandy Walker Syndrome is hydrocephalus associated with a posterior fossa cyst and dysgenesis of the cerebellum.1 It is a rare abnormality of CNS with reported incidence of 1 in 25000 live births.2 This is a case of 5 year old male case with truncal attaxia, dysarthric, scanning speech, hypotonia, occular dysmetria, poor pursuit, poor fine motor control and poor balance and coordination. An early diagnosis resulted in early intervention in motor, speech, psychological and pre academics skills at child development centre. This case is successfully managed with conservative rehabilitation plan preparing him for normal school.

DANDY-WALKER SYNDROME;

Introduction: Dandy-Walker Malformation is an inborn condition that includesthe triumvirate of cystic enlargement of the fourth ventricle, posterior fossa distension with riseof the tentorium and agenesis of cerebellar vermis. The purpose of this study is to determinethe Clinical presentation and associated complications, mortality and morbidity of patientundergoing placement of shunt with Y- connector in Dandy Walker Malformation. StudyDesign: Case Series comprised of 85 cases. Setting: Neurosurgery Ward of Tertiary CareHospital in Karachi. Period: February 2011 to December 2015. Methodology: All patients whowere presented in OPD with complaints reminiscent of DWM with accompanied Hydrocephalusand then underwent CT scan Brain without contrast to confirm the diagnosis were admitted.The patients who have previous history of operation and other co-morbid anomalies wereomitted. These patients undergo drainage of Ventricular system and Posterior Fossa cyst wasdone mutually via Dual Shunt including Ventricular-peritoneal and Cysto-peritoneal shunt withY connector. There were few complications and mortality after this surgical intervention whichwas noted for a month. All records were recorded and evaluated by SPSS v.20. Result: Avast majority of patients included were Female. The average age of patients was 2.5 years+/- 1 Standard Deviation. The chief complaint was Hydrocephalus, existing in all patients,after that cerebellar signs in 55 (64.7%) and other signs in 10 (11.8%) patients. Others signsincludes; milestones were delayed, atypical gait and few patients were suffered from psychiatricproblems. Complications which were observed were shunt; Fracture/Dislocation in 10 (11.8%),shunt blockage in 8 (9.4%), malpositioning is also 8 (9.4%), Intracranial Hemorrhage in 7(8.24%) patients and Infection in 10 (11.8%). These complications were observed within amonth of surgery. Unfortunately, two (2.35%) patient were also expired after surgical approach.Conclusion: It is concluded that Dandy Walker Malformation is categorized by a triumvirate.Hydrocephalus is a most common symptom and principal cause of referral to hospitals. Thecommonest difficulty acknowledged after shunting is Malfunction and shunt infections. Thelowest mortality is related to Dual Shunt with Y connector when compared to other approachesfor management of shunt with Y-connector. Thus, it is found to be a worthy decision in givenDWM patients.