Brainstem diffuse gliomas: radiologic findings.

Transcription

1 Brainstem diffuse gliomas: radiologic findings. Poster No.: C-2220 Congress: ECR 2013 Type: Educational Exhibit Authors: E. GARCIA MARTINEZ 1, D. H. Jiménez 1, L. Navarro Vilar 2, C. P. Fernandez Ruiz 1, M. Atares 3, F. Menor 1 ; 1 VALENCIA/ES, 2 Valencia, Va/ES, 3 Picaña, Valencia/ES Keywords: DOI: Neoplasia, Contrast agent-intravenous, MR, CT, Pediatric, Oncology, Head and neck /ecr2013/C-2220 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 ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR 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 ECR 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 and any other multimedia files are not available in the pdf version of presentations. Page 1 of 10

2 Learning objectives Review the radiological findings in CT and MR in patients diagnosed with brainsterm diffuse glioma. Background Brainstem diffuse gliomas have a poor prognosis and is important to recognize their image findings. These tumors are infiltrating astrocitomas, and most frequently arise in the pons, typically present in childhood (3 to 10 years of age) and make up 10-15% of all paedriatric brain tumors and 20-30% of paedriatric posterior fossa tumors. Typically patients present with multiple cranial nerve palsies and signs of raised intracranial pressure.cerebellar signs may also be elicited including ataxia, dysarthria, nystagmus and sleep apnoea. These tumours can be divided by location in mesencephalic, pontine( most common 60-75% of all cases) or medullary. There is an association with neurofibromatosis type I, which however carries a better prognosis with a more indolent course. Due to the high rate of severe complications with biopsy treatment is usually commenced without histological confirmation. Treatment usually comprises of chemotherapy only. In children over 3 years of age (or preferably even older) then radiotherapy may be considered. Necrosis may result from radiotherapy, however it may also be seen as part of the natural course of the tumour. Initial response can be dramatic and falsely reassuring.in the sporadic form the prognosis is poor with 2 year survival being only 20% (median survival less than 1 year). Imaging findings OR Procedure details Page 2 of 10

3 The pons is enlarged Fig. 1 on page 3,with the basilar artery are displaced anteriorly against the clivus and potentially engulfed Fig. 6 on page 7.The floor of the fourth ventricle is flattened Fig. 5 on page 6 and obstructive hydrocephalus may be present. Occasionally the tumour is exophytic Fig. 6 on page 7, either outwards into the basal cisterns or centrally in the 4 ventricle. Usually the tumour is homogenous pre-treatment, however in a minority of patients areas of necrosis may be present. The findings in CT:Typically hypodense Fig. 4 on page 5, with little if any enhancement and MR: T1 decreased intensity,t2:heterogeneously increased Fig. 5 on page 6 T1C: usually minimal enhance (can enhance post radiotherapy),dwi:usually no restricted,occasionally mildly restricted. Fig. 3 on page 4 Images for this section: Fig. 1: 5 year old girl with progressive headache, with bradypsychia and language alterations. CT:hypodense mass in the pons partially occluding the 4th ventricle without hydrocephalus.(brainstem diffuse Glioma) Page 3 of 10

4 Fig. 2: The same patient figure 1. Transverse and sagital T1 weighted images (2a) and T1 gadolinium-enhanced images (2b). The images shows infiltrative-expansive pontine lesion;it has a discreetly heterogeneous signal intensity without contrast and no contrast enhancement(brainstem diffuse Glioma) Page 4 of 10

5 Fig. 3: The same patient Figure 1.Transverse T2 weighted images(3a),flair(3b),dwi(3c). No restriction lesion in diffusion sequence. The ventricular system is intact.(brainstem diffuse Glioma) Page 5 of 10

6 Fig. 4: 6 year old boy with 1 week movement alterations. CT: Hypodense infiltrative lesion located in the brainstem,specially in the left centre-lateral,with an exophytic component than occludes the prepontine cistern(pontine-midbrain diffused glioma) Page 6 of 10

7 Fig. 5: The same patient figure 4. Sagital T1 weighted image (5a) and sagital T2 image (5b). The images shows increased pons by infiltrative-expansive lesion occupying the prepontine cistern and deforms the floor of the third ventricle;it has a heterogeneous signal intensity, decreased intensity in T1 and heterogeneously increased in T2. Fig. 5. Page 7 of 10

8 Fig. 6: The same patient figure 4 Transverse T1 weighted(upper images,6a)and T2(lower images, 6b) Infiltrative lesion located in the brainstem, specially in the left centre-lateral portion with an exophytic component than occludes the prepontine cistern, and contacts in more than 180 degrees the basilar artery and extends cranially to the left midbrain. (Pontine-midbrain diffused glioma) Page 8 of 10

9 Fig. 7: The same patient Figure 4. Transverse T1 weighted(upper images 7a) and T1 gadolinium-enhanced( lower images 7b) This lesion has a heterogeneous enhancement with various nodular hyper enhanced areas in the periphery(pontine-midbrain diffuse glioma) Page 9 of 10

10 Conclusion Diffuse brainstem gliomas are infiltrating astrocytomas, and most frequently arise in the pons. These tumours presents in childhood (3 to 10 years of age).symtoms are cranial nerve palsies and signs of raised intracranial pressure. In the sporadic form the prognosis is poor with 2 year survival being only 20% (median survival less than 1 year). Typically findings are hipodense lesions at CT, decreased intensity in T1, heterogeneously increased at T2, usually minimal enhanced in T1 Contrast. References 1. Barkovich AJ. Pediatric neuroimaging. Lippincott Williams & Wilkins. (2005) ISBN: Koeller KK, Rushing EJ. From the archives of the AFIP: pilocytic astrocytoma: radiologic-pathologic correlation. Radiographics. 24 (6): Nelson MD, Soni D, Baram TZ. Necrosis in pontine gliomas: radiation induced or natural history? Radiology. 1994;191 (1): Helton KJ, Phillips NS, Khan RB et-al. Diffusion tensor imaging of tract involvement in children with pontine tumors. AJNR Am J Neuroradiol. 2006;27 (4): Keating RF, Goodrich JT, Packer RJ. Tumors of the pediatric central nervous system. George Thieme Verlag. (2001). Personal Information Page 10 of 10