JOSS Rhombencephalosynapsis and Chiari II10.5005/jp-journals-10039-1143 Malformation with Spinal Deformities CASE REPORT Rhombencephalosynapsis and Chiari II Malformation with Spinal Deformities 1Abul Hasan, 2Sanjeev Shopra, 3Devendra K Purohit, 4Somnath Sharma ABSTRACT malformations or any other medical problems. He was Rhombencephalosynapsis is a rare congenital intracranial a full-term normal vaginal delivery, born with swell- malformation. Partial rhombencephalosynapsis is a variation of ing over the upper back. Patient’s mother did not have this anomaly with few reported cases. We report a unique case any antenatal medical supervision with no history of of a patient with partial rhombencephalosynapsis associated antenatal drug usage. Patient had episodes of cyanotic with Chiari II, and various spinal malformations, which is very spells in immediate postnatal period. Patient was oper- rare, and only few such cases have been reported in literature. ated for cervicothoracic meningomyelocele at the age of 1 These findings suggest that rhombencephalosynapsis can be associated with spinal malformations and, furthermore, that year, and now presented with complaints of progressive cases with the common features of rhombencephalosynapsis dorsal kyphoscoliosis and heaviness of right upper and and Chiari II malformation can exist. Such an association likely lower limbs, with abnormal gait pattern. On examination, represents a new anomaly of the hind brain with spine. patient’s stature corresponded to that of his father, but Keywords: Blocked vertebrae, Chiari II malformation, Kypho- having short neck with low-set ears and low posterior scoliosis, Rhombencephalosynapsis, Split cord. hairline, and with uneven shoulder blades and waist, as How to cite this article: Hasan A, Shopra S, Purohit DK, well as one hip higher than the other (Fig. 1). His neu- Sharma S. Rhombencephalosynapsis and Chiari II Malforma- rological examination was unremarkable except having tion with Spinal Deformities. J Spinal Surg 2017;4(3):123-125. slight right extensor hallucis longus weakness and gait Source of support: Nil abnormality due to severe kyphoscoliosis, has more Conflict of interest: None limited range of motion while walking with stiffer gait. On magnetic resonance imaging (MRI) brain, there was mild herniation of cerebellar tonsils in foramen INTRODUCTION magnum with peg-like appearance (Fig. 2), suggestive of Rhombencephalosynapsis is characterized by fusion of Chiari II malformation, with 4th ventricular compression the cerebellar hemispheres with vermian absence.1-10 It and proximal dilation of ventricles (Fig. 3). Dysplastic can be associated with various supratentorial anoma- cerebellum showing fusion across midline specially lies,1-10 and rarely with facial and hand anomalies;1,11,12 posteriorly suggested rhombencephalosynapsis (Fig. 4), however, its association with spinal anomalies as well as with septal agenesis. Splenium of corpus callosum was with cerebellar tonsillar herniations and tectal beaking hypoplastic. Rest brain imaging was normal. similar to that seen in Chiari II malformations13-15 has The MRI spine is suggestive of split cord at C6 to D2 not been reported previously. In this article, we report a (Fig. 5) with small syrinx in both hemicord, block verte- case with coexistent features of partial rhombencephalo- synapsis, Chiari II malformation, and spinal anomalies. CASE REPORT Our patient is a 14-year-old boy with normal mental status. He was the first child of a non-consanguineous couple. There was no family history of congenital 1Resident, 2Associate Professor, 3Senior Professor, 4Assistant Professor 1-4Department of Neurosurgery, S.M.S Medical College, Jaipur Rajasthan, India Corresponding Author: Abul Hasan, Resident, Department of Neurosurgery, S.M.S Medical College, Jaipur, Rajasthan, India Clinical photograph (short neck with, low hairline, Phone: +918955444516, e-mail: [email protected] Fig. 1: uneven shoulder blades and waist) The Journal of Spinal Surgery, July-September 2017;4(3):123-125 123 Abul Hasan et al Fig. 2: Saggital T2W MRI image showing herniation of Fig. 3: Axial MRI image showing dilatation of ventricles cerebellar tonsils in foramen magnum with peg-like appearance Fig. 4: Coronal T2W MRI image showing Dysplastic cerebellum Fig. 5: The MRI spine showing split cord with fusion across midline specially posteriorly brae seen at L2 to L3 levels with duplication of posterior elements and spina bifida. Evidence of split cord is also seen in lumbar region L2 to L3 levels (Fig. 6), cord is low lying and terminates at L4 level with tethering. Scoliosis at cervicothoracic junction and exaggerated dorsal scoliosis and lumbar lordosis is present. Segmentation anomaly in the form of block vertebrae was also noted from C7 to D2 level (Fig. 7). No features suggestive of atlantoaxial dislocation were present. Rest imaging and hematological tests were normal. The patient was advised customized brace and attached to follow-up. DISCUSSION Fig. 6: The MRI spine showing,split cord in lumbar region Rhombencephalosynapsis is a disorder of rhombencepha- lon. The most characteristic changes associated with the of aqueduct, hypoplastic or absent inferior olivary nuclei, condition include apposition or fusion of the dentate severe hypoplasia of the cerebellar hemispheres, and an nuclei and cerebellar hemispheric fusion, there is vermian isolated (trapped) fourth ventricle can be associated with agenesis. Absence of the nodulus results in a key hole- the condition.1-10 In our case, cerebellar changes mainly shaped fourth ventricle. Fusion of cerebellar peduncles posterior fusion were consistent with partial rhomben- and colliculi, gray matter heterotopia, stenosis or atresia cephalosynapsis with key hole-shaped fourth ventricle. 124 JOSS Rhombencephalosynapsis and Chiari II Malformation with Spinal Deformities is neural tube defect.9,10,13-16 Therefore, such wide spec- trum of spinal malformations are not found in patients of rhombencephalosynapsis. Tectal beaking, cerebellar tonsillar herniation, and meningomyelocele are consistent features of Chiari II malformation and are not previously reported with rhombencephalosynapsis; therefore, such coexistence of two embryologically different malforma- tion may represent a new anomaly. In conclusion, we report a patient who presented with features of partial rhombencephalosynapsis with Chiari II features and various spinal anomalies which is such a rare associa- tion. It may be a new anomaly of hindbrain with spine. REFERENCES Fig. 7: Segmentation anomaly 1. Truwit CL, Barkovich AJ, Shahanan R, Maroldo TV. MR imaging of rhombencephalosynapsis: report of three cases and review of the literature. AJNR Am J Neuroradiol 1991 The whole spectrum of supratentorial abnormalities Sep-Oct;12(5):957-965. associated with rhombencephalosynapsis is not present, 2. Demaerel P, Kendall BE, Wilms G, Halpin SF, Casaer P, only septal agenesis, with hypoplastic splenium of corpus Baert AL. 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