Cavum velum interpositum cyst causing symptomatic trapped ventricle: A case report

Transcription

1 Cavum velum interpositum cyst causing symptomatic trapped ventricle: A case report Poster No: R-0286 Congress: 2014 CSM Type: Scientific Exhibit Authors: T Singh, S Dupre; NAMBOUR/AU Keywords: CNS, Neuroradiology brain, Anatomy, CT, MR, Endoscopy, Cerebrospinal fluid DOI: /ranzcr2014/R-0286 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply RANZCR/AIR/ACPSEM's endorsement, sponsorship or recommendation of the third party, information, product or service RANZCR/AIR/ ACPSEM is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited You agree to defend, indemnify, and hold RANZCR/AIR/ACPSEM harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages Please note: Links to movies, ppt slideshows, doc documents and any other multimedia files are not available in the pdf version of presentations Page 1 of 12

2 Aim To describe the embryology, anatomy and pathology of cavum velum interpositum (CVI) cysts, and to present a case of a CVI cyst resulting in a trapped lateral ventricle Methods and materials Thorough literature search for the terms "cavum velum interpositum" together with related search terms "cavum septum pellucidum" and "cavum vergae" was conducted, using various search engines Cavum velum interpositum : The velum interpositum space is the subarachnoid space between the connected fornix and its respective choroid plexus, and the choroid forming the roof of the third ventricle inferiorly It is an anterior extension of the quadrigeminal plate cistern located superior to the pineal gland If this potential space is dilated, then it is known as the cavum velum interpositum [1] The clinical symptoms reported in patients with CVI cysts include macro- crania, developmental delay, autism, epilepsy, seizures, and hydrocephalus In the absence of obstructive hydro-cephalus, the relationship of these symptoms to a CVI cyst found on imaging is not clear [2] Most cases of cavum velum interpositum occur in newborns [3] The differential diagnosis of these midline cystic brain lesions includes an enlarged third ventricle, a vein of Galen aneurysm, an interhemispheric cyst in relation to the agenesis of the corpus callosum, and a suprasellar arachnoid cyst [3,4] A typical axial MRI or CT scan will display a triangular-shaped CSF space between the lateral ventricles On sagittal images, a cavum velum interpositum appears like a slit with collections of CSF behind the foramen of Monro, below the fornices, and above the tela choroidea of the third ventricle [5] Cavum septum pellucidum: Page 2 of 12

3 When a septum pellucidum has a separation between its two leaflets this is termed a cavum septum pellucidum The corpus callosum forms from anterior to posterior, except the rostrum, which connects the genu and the lamina terminalis Because of this, the leaflets of the septum pellucidum are pulled towards the lamina terminalis, sealing the cavum from the posterior fornix to the rostrum of the corpus callosum, due to the frontalization of fibers in the genu portion by the seventh month [6] When the gap is not closed, then the condition remains [1] Cavum vergae: First described by Verga and sometimes referred to as Verga's ventricle Cavum vergae is an extension of a cavum septum pellucidum posteriorly past the columns of the fornix and foramina of Monro [1] This condition takes place when there is a separation of the leaflets of the septum pellucidum with posterior extension to the splenium of the corpus callosum The anterior columns of the fornix separate the anterior cavum septum pellucidum and the posterior cavum vergae [1] Results CVI is an uncommon incidental finding on imaging studies Cystic dilatation can occur, but there are very few reported cases of patients with symptoms, or ventricular obstruction attributable to the malformation We report a case with of a symptomatic trapped ventricle secondary to CVI cyst HISTORY: A 62 year old female presented to the emergency deprtment with a 1month history of headaches and truncal ataxia Non Contrast CT Head : Page 3 of 12

4 Cavum Vellum Interpositum cyst measuring 5cm AP x 42 cm transverse x 46cm craniocaudal, with mass effect resulting in a trapped lateral ventricle body, trigone and temporal horn [Fig 2] MRI Brain: Marked dilation of the posterior portion of the right lateral ventricle including the posterior horn and temporal horns The choroid plexus is deviated anteriorly and abutts the wall of the lateral trigone, with a septation just anterior to this No signal change in the surrounding parenchyma with loss of volume of the surrounding parenchyma, consistent with a chronic insult SURGERY: Right parietal burr hole, and durotomy was made With endoscopic approach fenestration of cyst into the left lateral ventricle and anteriorly into the right frontal horn was prformed POST OPERATIVE COURSE: The patient remained symptom free, and was discharged None of the symptoms persisted A CT head was performed four years post fall which revealed persisting dilatation of the right ventricular system (consistent with chronic dilatation and adjacent volume loss), with no transependymal CSF spread or other signs of CSF obstruction Images for this section: Page 4 of 12

5 Fig 1: Axial Non Contrast Image of the brain with dilation of the lateral ventricles ( more on the right) Page 5 of 12

6 Fig 2: Axial non-contrast images showing the margins of the CVI cyst Page 6 of 12

7 Fig 4: Sagittal non contrast CT demonstrating dilation of both temporal and occipital horns of the right lateral ventricle Page 7 of 12

8 Fig 6: Coronal Non Contrast CT Demonstrates dilation of right lateral ventricle Page 8 of 12

9 Fig 3: Axial T2 image showing the CVI cyst Page 9 of 12

10 Fig 5: Sagittal T2 image demonstrating dilation of both temporal and occipital horns of the right lateral ventricle Page 10 of 12

11 Conclusion Whilst Cavum Velum Interpositum is usually an asymtomatc incidental finding on imaging in adults Encystment can occur, which again is mostly asymptomatic Our case adds to the literature describing good response to fenestration surgery in symptomatic CVI Personal information Dr Thakur Manas Singh Radiology Registrar Nambour Hospital Queensland Dr Simon Dupre (FRANZCR) Consultant Radioilogist Nambour Hospital Queensland References 1 Tubbs RS, Krishnamurthy S, Verma K, Shoja MM, Loukas M, Mortazavi MM, CohenGadol AA: Cavum velum interpositum, cavum septum pellucidum, and cavum vergae: a review : Childs Nerv Syst (2011) 27: Tong CKW, Singhal A, Cochrane DD: Endoscopic fenestration of cavum velum interpositum cysts: a case study of two symptomatic patients: Page 11 of 12

12 Childs Nerv Syst (2012) 28: Eisenberg VH, Zalel Y, Hoffmann C, Feldman Z, Achiron R(2003) Prenatal diagnosis of cavum velum interpositum cysts: significance and outcome Prenat Diagn 23: Vergani P, Locatelli A, Piccoli MG, Ceruti P, Patane L, Paterlini G et al (1999) Ultrasonographic differential diagnosis of fetal intracranial interhemispheric cysts Am J Obstet Gynecol 180: Mourgela S, Sakellaropoulos A, Gouliamos A, Anagnostopoulou S (2010) Cavum veli interpositi: why this anatomical variant exists? Int J Anatomical Var 3:2-5 6 Larroche JC, Baudey J (1961) Cavum septi lucidi, cavum Vergae, cavum veli interpositi: cavities of the median line Anatomical and pneumoencephalographic study in the neonatal period Biol Neonat 3: Page 12 of 12