SUBMITTED 21 APR 22 1 REVISION REQ. 21 JUL 22; REVISION RECD. 2 AUG 22 2 ACCEPTED 24 AUG 22 3 ONLINE-FIRST: September 2022 4 DOI: https://doi.org/10.18295/squmj.9.2022.055 5 6 Imaging Features of Dyke-Davidoff-Masson Syndrome 7 Asma AlHatmi,1 Talal Almashaikhi,2 *Eiman Al Ajmi3 8 1Department of Radiology, Ibri Hospital, Ibri, Oman; Departments of 2Clinical Physiology and 9 3Radiology and Molecular Imaging, Sultan Qaboos University Hospital, Muscat, Oman 10 *Corresponding Author’s e-mail: ealajmi@squ.edu.om 11 12 Introduction 13 A 42-year-old man presented to the adult epilepsy clinic in 2019 at Sultan Qaboos University 14 Hospital, Muscat, Oman, with right motor seizures with occasional generalization and loss of 15 consciousness, right-side hemiparesis, and low intellectual capacity since early childhood. The 16 patient had perinatal hypoxic ischemic injury due to a difficult delivery, which resulted in spastic 17 cerebral palsy. His developmental history revealed delayed milestones and learning difficulties at 18 school. His seizure episodes have increased in frequency over the years, requiring treatment with 19 multiple antiepileptics. Despite being on four antiepileptic drugs, the patient continued to 20 experience very frequent seizures. On examination, he had slurred speech and right facial 21 deviation. He was able to walk without support, with a circumduction gait. There was right-sided 22 spastic hemiparesis with brisk tendon reflexes and an extensor plantar response. 23 24 An electroencephalogram (EEG) was done and showed left hemispheric cerebral dysfunction 25 with left hemispheric onset focal motor seizures. Computed tomography (CT) and magnetic 26 resonance imaging (MRI) of the brain were done and revealed atrophy of the left cerebral 27 hemisphere with ipsilateral compensatory thickening of skull bones and hyperpneumatization of 28 the left frontal and sphenoidal sinuses. The diagnosis of Dyke-Davidoff-Masson (DDM) 29 syndrome was made based on clinical and radiological findings. The patient was managed with 30 antiepileptic medications, muscle relaxants, and physiotherapy. Due to his intractable seizures, 31 mailto:ealajmi@squ.edu.om he was offered surgical intervention at an outside facility. We present a case of DDM syndrome 32 with characteristic clinical and radiological findings. It is a rare entity with few reported cases in 33 literature. To best of our knowledge, this is the first case to be reported in our institution. 34 35 Informed patient consent for publication was obtained. 36 37 Comment 38 DDM syndrome is a rare condition that was described for the first time in 1933 by Dyke, 39 Davidoff, and Masson.1,2 Those researchers described the plain skull radiograph features of nine 40 patients who presented with seizures, hemiparesis, facial asymmetry, and mental retardation.1 41 42 There are two types of DDM syndrome: congenital and acquired.2 The congenital or infantile 43 type presents early in infancy, secondary to previous intrauterine brain insults like vascular 44 occlusion or anomaly of the middle cerebral artery mainly.2,3 The acquired type occurs later in 45 childhood secondary to variable causes affecting brain perfusion like infection, prolonged febrile 46 seizure, trauma, hemorrhage, or ischemia.2 Our patient presented with hemiplegia and seizures 47 since childhood, which is likely due to the hypoxic ischemic injury that he sustained during the 48 perinatal period. The classical imaging features of this condition are unilateral cerebral atrophy 49 with ipsilateral calvarial thickening and hyperpneumatization of the ipsilateral frontal sinus.1,3 50 Other reported findings are ipsilateral falcine displacement, elevation of the petrous ridge and 51 wing of sphenoid bone, atrophy of ipsilateral basal ganglia and brainstem and contralateral 52 cerebellum, and hyperpneumatization of ipsilateral mastoid air cells.2 53 54 Our patient has the classic clinical and imaging features described in the literature for DDM 55 syndrome. He had CT [Figure 1] and MRI [Figure 2] of the brain, which revealed unilateral left-56 sided cerebral atrophy with ipsilateral compensatory hypertrophic thickening of skull bones. 57 There was also hyperpneumatization of the left frontal and sphenoidal sinuses and the left 58 mastoid process. Atrophy of the ipsilateral thalamus, cerebral peduncle, and falttending of the 59 left anterior surface of the pons and medulla in keeping with Wallerian degeneration, and 60 contralateral cerebellar atrophy were present. On time-of-flight MR angiogram [Figure 3], the 61 left middle cerebral artery and its branches were smaller compared to the right side. It is 62 noteworthy to mention that the imaging findings of cerebral hemiatrophy, features of Wallerian 63 degeneration, and cossed cerebellar diaschisis due to impaired neuronal connections can be seen 64 after various major cerebral inulsts, commonly infarcts, at any time in life. The presence of the 65 findings varies depending on the severity of the insults. The presence of skull and sinus 66 hypertrophy is seen, however, in insults that happen early in life, as classically described in 67 DDM syndrome. 68 69 The most common differential diagnosis for this syndrome is chronic Rasmussen encephalitis, 70 Sturge-Weber syndrome, basal ganglia germinoma, and Fishman syndrome.1,2 However, 71 differentiation between them can be made by clinical and radiological findings. For example, 72 chronic Rasmussen encephalitis is a rare progressive inflammatory disease affecting children 73 who usually present with seizures and cognitive impairment. Imaging findings show unilateral 74 cerebral atrophy without associated skull changes.1 Patients with Sturge-Weber syndrome 75 usually present with seizures, mental retardation, and a typical port wine stain on the face in the 76 distribution of the ophthalmic division of the trigeminal nerve. On imaging, there will be 77 unilateral cerebral atrophy with increased angiomatosis and sometimes ipsilateral cortical tram 78 track calcifications.2,3 DDM syndrome has a wide spectrum of presentation, ranging from mild 79 symptoms to severely disabling symptoms. 80 81 Refractory seizures remain the most challenging complaint.4,5 Patients with refractory seizures 82 may benefit from surgical interventions like functional hemispherectomy, with a reported 83 success rate of 85% in selected cases.1,4 However, it is highly associated with long term adverse 84 effects like obstructive hydrocephalus and chronic subdural hygromas.2,4 Hemispherotomy is 85 another surgical option that is also effective and associated with fewer complications. 86 Rehabilitation, physiotherapy, speech therapy, and occupational therapy are important to 87 improve the quality of life.4,5 Our patient was managed with antiepileptic medications, muscle 88 relaxants, and physiotherapy. Due to his intractable seizures, he was offered surgical intervention 89 at an outside facility. 90 91 References: 92 1.Arora R, Rani JY. Dyke-davidoff-masson syndrome: imaging features with illustration of two 93 cases. Quant Imaging Med Surg 2015;5(3):469-471. doi: 10.3978/ j.issn.2223-4292.2014.11.17 94 2.Ayas ZÖ, Asil K, Öcal R. The clinico-radiological spectrum of Dyke-Davidoff-Masson 95 syndrome in adults. Neurol Sci. 2017;38(10):1823-1828. doi:10.1007/s10072-017-3074-7 96 3.Gökçe E, Beyhan M, Sade R. Radiological imaging findings of Dyke-Davidoff-Masson 97 syndrome. Acta Neurol Belg. 2017;117(4):885-893. doi:10.1007/s13760-017-0778-7 98 4.Kim JS, Park EK, Shim KW, Kim DS. Hemispherotomy and Functional Hemispherectomy: 99 Indications and Outcomes. J Epilepsy Res. 2018;8(1):1-5. Published 2018 Jun 30. 100 doi:10.14581/jer.18001 101 5.Kumar NV, Gugapriya TS, Guru AT, Kumari SN. Dyke-Davidoff-Masson syndrome. Int J 102 Appl Basic Med Res. 2016;6(1):57-59. doi:10.4103/2229-516X.174016 103 104 105 106 Figure 1: Axial unenhanced CT of the brain with brain and bone windows shows (A) severe left-107 side cerebral atrophy with ex-vacuo dilatation of the ipsilateral lateral ventricle, (B) left-side 108 compensatory calvarial hypertrophy (arrows), (C) hyperpneumatization and enlargement of the 109 left frontal sinus (long arrow) and left mastoid air cells (short arrow). 110 111 112 113 A B C 114 Figure 2: Axial (A,B) and coronal (C) T2 weighted images demonstrate severe atrophy of the 115 left cerebral hemisphere with (A) left thalamic atrophy (arrow), (B) left cerebral peduncle 116 atrophy (arrow) and (C) contralateral cerebellar atrophy (arrow). 117 118 119 120 Figure 3: Coronal time-of-flight MR angiogram: The left main cerebral artery and its branches 121 are smaller than the right side. (arrow). 122