The Neuroradiology Journal 22: 435-438, 2009
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Meningocerebral Angiodysplasia: Post-Mortem Magnetic Resonance Imaging and Autopsy A Case Report M. VANĚČKOVÁ*, Z. SEIDL*,*****, B. GOLDOVA**, I. VITKOVA**, A. BAXOVA***, P. CALDA**** * Department of Radiology; ** Department of Pathology; *** Institute of Biology and Department of Medical Genetics; **** Department of Obstetrics and Gynaecology, First Faculty of Medicine, General Teaching Hospital, Charles University in Prague; Prague, Czech Republic; ***** Medical College, Prague 5; Czech Republic
Key words: foetus, meningocerebral angiodysplasia, autopsy, magnetic resonance imaging
SUMMARY – This case report describes a finding of vascular malformation of an aborted foetus of gestational age of the 22nd week. This concerns meningocerebral angiodysplasia, located in the posterior fossa and around the thalami. This disease is rare and is often accompanied by renal agenesis. The finding was complicated by hydrocephalus. Our report compares all three diagnostic methods (prenatal ultrasonography, post-mortem MR and autopsy). Prenatal ultrasonography described only hydrocephalus and reduction of cerebral parenchyma. MR displayed the extent of the malformation, the exact diagnosis was however determined by histological examination. MR described agenesis of structures of midbrain, which was confirmed by autopsy.
Introduction It is necessary to determine a final diagnosis of malformation precisely to be able to provide parents with the relevant information on the type of congenital malformation of their foetus or newborn. Autopsy is the gold standard at present 1,2. Unfortunately there are situations where autopsy is insufficient. It is primarily in cases of pronounced dilatation of the ventricular system or presence of extended cysts (hydrocephalus, hydranencephaly, schizencephaly, porencephaly…), or if autolysis is already developed or it is not possible to perform fixation by formol 3. For this reason post-mortem MR becomes a complementary method to autopsy and in several cases the MR finding is the only method to determine diagnosis 1-4. Report A 33-year-old octigravida, septipara (five healthy children, one son died one month after birth because of a congenital malforma-
tion, another son died 2.5 months after birth because of a congenital malformation of CNS). This pregnancy had no complications. Sonographic evaluation of the fetal morfology in the 12th week did not show any abnormalities, the first trimester screening for Down syndrome was negative, MS-AFP evaluated in the 16th week was 0.66 MoM. Ultrasonography in the 22nd week described hydrocephalus, lateral ventricles were dilatated less than 21 mm, 4 mm of cerebral parenchyma remained (figure 1). The pregnant woman was informed about the finding of ultrasonography and requested to terminate pregnancy in accordance with the law. Abortion was induced in the 22nd week and post-mortem MR was performed immediately, followed by autopsy. MR was performed in all orthogonal planes in T2W image with parameters: TE 120 ms, TR 5272 ms, thickness of slide was 3 mm (THK 3.0/0.3). Post-mortem MR displayed triventricular hydrocephalus, fronto-occipital diameter (FOD) was 61 mm, cerebral biparietal diameter (BPD) 58 mm, bone BPD 59 mm, atrial diameter (AD) was 14mm, lateral 435
Meningocerebral Angiodysplasia: Post-Mortem Magnetic Resonance Imaging and Autopsy
Figure 1 Prenatal ultrasonography in the 22nd week, note dilatation of lateral ventricles and noticeable reduction of cerebral parenchyma.
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M. Vaneˇcˇková
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Figure 2 A-C) Post-mortem MR, sagittal scans in T2W. There is an irregular hyposignal structure corresponding to extensive vascular malformation around the brainstem, ventral and dorsal area, in the tentorial region and supratentorially around the thalami. The brainstem and occipital lobe are deconfigurated, most probably on basis of autolysis, in the area of the brainstem undoubtedly also because of extensive vascular malformation. C) Dilatation of the lateral ventricles.
diameter (DV3) 6 mm. In the area of the posterior fossa, mainly in the tentorial region, around the brainstem, ventral area in front of the pons and mesencephalon, and also in the 436
dorsal area, an irregular structure was visible, which was a hyposignal and in some places isosignal with cerebral parenchyma in T2W images. There was a similar structure of similar
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Figure 3 Post-mortem MR, transverse view, dilatation of the lateral ventricles is displayed. A hyposignal stripe is seen in lateral ventricles occipitally and in the subarachnoid space; the stripe corresponds to the decay products of haemoglobin. Bleeding could be the cause of extensive hydrocephalus.
The Neuroradiology Journal 22: 435-438, 2009
Figure 4 Histotopogram from the area of the pons and cerebellar hemispheres. There are multiple enlarged capillaries filled with blood in the cerebral and in cerebellar parenchyma, the pia matter is also affected in several places and corresponds to the pathologic unit of meningocerebral angiodysplasia.
Figure 5 Detail of the thalamus. HE stain; meningocerebral dysplasia.
MR signal present also around the thalami (figure 2A-C). There was a hyposignal stripe in the area of the lateral ventricles and also the third ventricle, which most probably corre-
spond to decay products of haemoglobin, and there was also subarachnoid bleeding (figure 3). We displayed neither corpus callosum nor septum pellucidum. Conclusion of post-mor437
Meningocerebral Angiodysplasia: Post-Mortem Magnetic Resonance Imaging and Autopsy
tem MR was triventricular hydrocephalus and extensive vascular malformation in the region of the posterior fossa and laterally around the thalami. Autopsy was performed immediately after post-mortem MR. Autopsy proved dilatation of all ventricles, septum pellucidum was not found. Dark red vascular tissue of maximal width of 2 mm was apparent around the thalami, pons and cerebellar hemispheres. Histological examination of all affected regions was similar and defined as meningocerebral angiodysplasia (figures 4, 5). The foetal karyotype determined by examination of amniotic fluid was normal, 46, XX. Discussion Post-mortem MR displayed an extensive vascular malformation, which was confirmed by autopsy, histologically specified as meningocerebral angiodysplasia. MR described that the midbrain is absent, and this was confirmed by autopsy. MR finding of interventricular haemorrhage could explain the cause of hydrocephalus. Prenatal ultrasonography described only extensive hydrocephalus with reduction of cerebral parenchyma. According to the new nomenclature, angiodysplasia is a unifying concept for all vascular malformations of different organ systems (musculoskeletal angodysplasia, visceral angiodysplasia, pulmonary angiodysplasia, central nervous system angiodysplasia) 5. There are four types of angiodysplasia in the CNS (arteriovenous malformation, cavernous malformations, venous malformations and teleangiectasias 5. According to the pathological classification,
M. Vaneˇcˇková
meningocerebral angiodysplasia and renal agenesis is a sporadic disease resulting in a minimal survival rate of newborns or premature infants. The histological signs are diffuse angiodysplasia, which is formed by enlarged capillaries and veins. They are located on the meninges, cortex, cerebellum and brainstem. The situation can be complicated by thrombosis and can result in infarctions, and bleeding, which could apply in this case. It can cause gliosis and calcification in cerebral parenchyma (in the cortex and also in white matter) 6. Potter’s facies, contraction deformities of the extremities, pulmonary hypoplasia and bilateral renal agenesis are connected with this unit. No renal agenesis or other pathologies with the exception of meningocerebral angiodysplasia were observed. The leptomeninges are extremely vascularized, which is the cause of the subarachnoid haemorrhage, in this case the bleeding was also interventricular. There was also cortical atrophy, cortical necrosis and necrosis of white matter as well as frequent calcifications or bleeding in connection with this unit 6. This malformation was diagnosed immediately following its inception, and the complications mentioned above had not yet been formed. Autopsy and post-mortem MR were performed to provide us with final information on the type of congenital malformation, a second no less important task was to specify prenatal ultrasonography on the basis of the feedback 1-3. Acknowledgement This study was supported by the grant MZOVFN2005, MSMTO21620849.
References 1 Whitby E, Paley MN, Cohen M et Al: Post-mortem fetal MRI: What do we learn from it? Eur J Radiol 57: 250-255, 2006. 2 Griffiths PD, Paley MNJ, Whitby EH: Post-mortem MRI as an adjunct to fetal or neonatal autopsy. Lancet 365: 1217-73, 2005. 3 Vaneckova M, Seidl Z, Goldova B et Al: Post-mortem magnetic resonance imaging and its irreplaceable role in determining CNS malformation (hydranencephaly). Case Report. Brain Devel DOI 10.1016/j.braindev. 2009.03.011, 2009. 4 Sebire NJ: Towards the minimally invasive autopsy? Ultrasound Obstet Gynecol 28: 865-867, 2006. 5 Lie JT: Angiodysplasia: New look at an old conundrum. Cardiovascular Pathology 6 (5): 247-259, 1997.
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6 Ellison D, Love S, Chimelli L et Al: Miscellaneous pediatric disorders. In: Neuropathology 2nd ed., Edinburgh, Scotland: Mosby Publishing 2004: 149- 151.
M. Vaněčková, MD, PhD MRI Unit, Department of Radiology 1st Faculty of Medicine Charles University in Prague Katerinska 30, 128 08 Praha 2 Czech Republic Tel.: +420 224965454 Fax: +420 224965058 E-mail:
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