Diagnostic Pitfalls of Macrocephaly and Intracranial Dural Arteriovenous Fistulas: Connecting the Dots With the Red Flags.

Macrocephaly is defined as an abnormal increase in head circumference greater than two standard deviations above the mean for a given age and sex. We present the case of a 16-month-old boy with congenital progressive macrocephaly, who was referred to our hospital for a ventriculoperitoneal shunt placement for external hydrocephalus diagnosed at 13 months of age. The patient had a febrile seizure 12 hours after the shunt was placed and the emergency CT exam revealed collapsed ventricles and a right frontal subdural collection, suggestive of an over-drainage and intracranial hypotension. A subsequent electroencephalogram (EEG) revealed some anomalies, but the patient was discharged two days later due to having no neurological symptoms after being placed on anticonvulsants. The patient returned to the hospital one week later due to recurrent seizures. Further clinical examination revealed prominent and tortuous veins of the skull, palpated in the left occipital region. A thrill and a left carotid murmur were heard during auscultation. A subsequent brain MRI with MR arteriography and venography was performed in search of an explanation for hydrocephaly. The sequences were suggestive of a dural arteriovenous fistula, which was confirmed and then treated using coils during an interventional angiography. A second procedure was performed two months later to complete the embolization, with subsequent imaging follow-ups showing the procedure to have been successful. The measurement of the cranial circumference, its regular evaluation, and its evolution allow a hierarchical diagnosis strategy by distinguishing primary and secondary macrocephaly, progressive or not. Dural arteriovenous fistulas (DAVF) are an under-appreciated cause of macrocephaly, with which they are associated in 35% of cases. Intracranial DAVFs are pathologic shunts between dural arteries and dural venous sinuses, meningeal veins, or cortical veins. Patients with DAVFs may be completely asymptomatic. Symptoms, when present, may range from neurological deficits, seizures, and hydrocephaly to fatal hemorrhage. The symptoms depend on the location and venous and drainage patterns of the DAVF. They can be difficult to identify on routine MRIs unless specifically searched for, especially in cases of technically suboptimal examinations. We aim to give a practical approach to identify the clinical clues that warrant further investigation. Several specific protocols exist regarding the management of macrocephaly and should be followed carefully once a diagnosis has been reached, but further studies are needed to integrate more clinical and neuroimaging findings to permit an early diagnosis.

A First Case of Acute Flaccid Myelitis Related to Enterovirus D68 in Belgium: Case Report.

Introduction: We describe the first case of acute flaccid myelitis (AFM) related to enterovirus D68 (EV-D68) infection in Belgium. The clinical and radiological presentation of AFM associated with EV-D68 although well described currently remains a challenging diagnosis. Through this interesting clinical case, we aimed to review the differential diagnosis of acute flaccid palsy in a child and discuss the specific point of interest related to AFM. Case Presentation: We present the case of a 4-year-old girl with a torticollis associated with an acute palsy of the right upper limb. The magnetic resonance imaging revealed an increased T2 signal intensity of the entire central gray matter of the cervical cord with involvement of the posterior brainstem. A polymerase chain reaction (PCR) conducted on a nasopharyngeal swab was found positive for EV-D68. The definition of AFM proposed by the Center for Disease Control and Prevention (CDC) is an acute-onset flaccid weakness of one or more limbs in the absence of a clear alternative diagnosis and the radiological evidence of gray matter involvement on an MRI picture, and our case fits these two criteria. A prompt and detailed workup is required to distinguish this emergent disease from other forms of acute flaccid palsy. The functional prognosis of AFM is poor, and there are no evidence-based treatment guidelines so far. Conclusion: AFM is an emerging pathology that requires the attention of pediatricians to quickly rule out differential diagnoses and adequately manage the patient. Further research is needed to optimize treatments, improve outcomes, and provide scientifically based guidelines.

Radiological characterization of pediatric intramedullary astrocytomas: Do they differ from adults?

Introduction: The incidence of intramedullary spinal cord tumors ranges from 2 to 4% of all central nervous system tumors. Only 6-8% are astrocytomas. The gold standard to diagnose a spinal cord tumor is the spinal cord MRI in toto. Specific radiological criteria orient the diagnosis of the intradural intramedullary lesion. Most of the authors studied adult populations of astrocytomas. However, pediatric astrocytomas present certain particularities. Research question: This work aims to determine if the usual radiological criteria of intramedullary astrocytomas (IMAs) are different depending on the patient's age. Material & methods: We evaluated the radiological features of IMAs in adult and pediatric groups through a retrospective study. Results: We collected 31 patients with IMAs (11 children and 20 adults). We observed some trends but we did not highlight any statistically significant difference between all the radiological criteria studied (sagittal and axial spinal cord localization, T1-and T2-weighted characteristics, contrast uptake, infiltrating character, presence of necrosis, heterogeneous lesion, necrotic, hemorrhagic, presence of edema) and the patient's age. Discussion & conclusion: Given the rarity of IMAs and the lack of large specific pediatric studies, it seems essential to routinely report all cases encountered and create multicentric pediatric databases to draw more robust conclusions.

Childhood craniopharyngioma: a retrospective study of children followed in Hôpital Universitaire de Bruxelles.

Introduction: Craniopharyngiomas (CPs) are benign brain tumors accounting for 5 - 11% of intracranial tumors in children. These tumors often recur and can cause severe morbidity. Postoperative radiotherapy efficiently controls and prevents progression and recurrence. Despite advancements in neurosurgery, endocrinological, visual, and neuropsychological complications are common and significantly lower the quality of life of patients. Methods: We performed a retrospective study, including all patients younger than sixteen diagnosed with CP between July 1989 and August 2022 and followed up in Hôpital Universitaire de Bruxelles. Results: Nineteen children with CP were included, with median age of 7 years at first symptoms and 7.5 at diagnosis. Common symptoms at diagnosis were increased intracranial pressure (63%), visual impairment (47%), growth failure (26%), polyuria/polydipsia (16%), and weight gain (10.5%). As clinical signs at diagnosis, growth failure was observed in 11/18 patients, starting with a median lag of 1 year and 4 months before diagnosis. On ophthalmological examination, 27% of patients had papillary edema and 79% had visual impairment. When visual disturbances were found, the average preoperative volume was higher (p=0.039). Only 6/19 patients had gross total surgical resection. After the first neurosurgery, 83% experienced tumor recurrence or progression at a median time of 22 months. Eleven patients (73%) underwent postsurgical radiotherapy. At diagnosis, growth hormone deficiency (GHD) was the most frequent endocrine deficit (8/17) and one year post surgery, AVP deficiency was the most frequent deficit (14/17). Obesity was present in 13% of patients at diagnosis, and in 40% six months after surgery. There was no significant change in body mass index over time (p=0.273) after the first six months post-surgery. Conclusion: CP is a challenging brain tumor that requires multimodal therapy and lifelong multidisciplinary follow-up including hormonal substitution therapy. Early recognition of symptoms is crucial for prompt surgical management. The management of long-term sequelae and morbidity are crucial parts of the clinical path of the patients. The results of this study highlight the fundamental importance of carrying out a complete assessment (ophthalmological, endocrinological, neurocognitive) at the time of diagnosis and during follow-up so that patients can benefit from the best possible care.

Clinicopathological and molecular characterization of a case classified by DNA­methylation profiling as "CNS embryonal tumor with BRD4-LEUTX fusion".

Central Nervous System (CNS) embryonal tumors represent a heterogeneous group of highly aggressive tumors occurring preferentially in children but also described in adolescents and adults. In 2021, the CNS World Health Organization (WHO) classification drastically changed the diagnosis of the other CNS embryonal tumors including new histo-molecular tumor types. Here, we report a pediatric case of a novel tumor type among the other CNS embryonal tumors classified within the methylation class "CNS Embryonal Tumor with BRD4-LEUTX Fusion". The patient was a 4-year girl with no previous history of disease. For a few weeks, she suffered from headaches, vomiting and mild fever associated with increasing asthenia and loss of weight leading to a global deterioration of health. MRI brain examination revealed a large, grossly well-circumscribed tumoral mass lesion located in the left parietal lobe, contralateral hydrocephalus and midline shift. Microscopic examination showed a highly cellular tumor with a polymorphic aspect. The majority of the tumor harbored neuroectodermal features composed of small cells with scant cytoplasm and hyperchromatic nuclei associated with small "medulloblastoma-like" cells characterized by syncytial arrangement and focally a streaming pattern. Tumor cells were diffusely positive for Synaptophysin, CD56, INI1 and SMARCA4 associated with negativity for GFAP, OLIG-2, EMA, BCOR, LIN28A and MIC-2. Additional IHC features included p53 protein expression in more than 10% of the tumor's cells and very interestingly, loss of H3K27me3 expression. The Heidelberg DNA-methylation classifier classified this case as "CNS Embryonal Tumor with BRD4:LEUTX Fusion". RNA-sequencing analyses confirmed the BRD4 (exon 13)-LEUTX (exon 2) fusion with no other molecular alterations found by DNA sequencing. Our case report confirmed that a new subgroup of CNS embryonal tumor with high aggressive potential, loss of H3K27me3 protein expression, BRDA4-LEUTX fusion, named "Embryonal CNS tumor with BRD4-LEUTX fusion", has to be considered into the new CNS WHO classification.

Posterior reversible encephalopathy syndrome revealing acute post-streptococcal glomerulonephritis.

A case of acute encephalopathy with posterior corticosubcortical vasogenic edema on magnetic resonance imaging is reported. Angiography showed cerebral arterial vasospasm. A diagnosis of acute post-streptococcal glomerulonephritis was made 2 days after admission. This report highlights the fact that acute post-streptococcal glomerulonephritis can be revealed by a posterior reversible encephalopathy syndrome and that cerebral vasospasm can concur with vasogenic edema in this condition.

Persistent hydrocephalus after early surgical management of posterior fossa tumors in children: is routine preoperative endoscopic third ventriculostomy justified?

OBJECT: The authors evaluate the incidence of persistent hydrocephalus after early surgical management of pediatric posterior fossa tumors and the indicators for routine preoperative endoscopic third ventriculostomy (ETV). METHODS: Between 1989 and 2004, 160 children with a posterior fossa tumor were treated at Erasme Hospital in Brussels, Belgium. Hydrocephalus was present at admission in 114 of the patients. Thirty-one patients had severe hydrocephalus (Evans index [EI] > 0.4). Twenty-four of these and the 83 patients with mild hydrocephalus (EI between 0.3 and 0.4) were treated with early posterior fossa surgery (Group 1; 107 patients). In this group, 93 patients underwent a total or subtotal tumor resection associated with external ventricular drainage (Group 1A), and 14 underwent a stereotactic biopsy associated with an ETV (Group 1B). The 53 remaining patients underwent elective posterior fossa surgery (Group 2). Early tumor resection (Group 1A) resolved hydrocephalus in 85 (91%) of 93 patients, whereas an ETV resolved intracranial hypertension in 11 patients (Group 1B). In Group 1, persistent hydrocephalus affected 11 (10%) of 107 patients, seven of whom had symptoms and were treated (three with shunts and four with ETVs). Persistent hydrocephalus was more frequent in children with severe preoperative hydrocephalus (p = 0.002) and with medulloblastomas (p = 0.0154). A total of 22 technically successful ETV procedures were performed. The ETV success rate for controlling hydrocephalus was 81% (18 of 22) and the rate of severe complications was 9% (two of 22). CONCLUSIONS: An ETV is an efficient procedure for controlling hydrocephalus associated with posterior fossa tumor. The authors confirm that a routine postoperative ETV is indicated for treating persistent hydrocephalus. For preventing it, however, they recommend early posterior fossa surgery whenever possible. The low rate of persistent hydrocephalus does not justify adopting routine preoperative ETVs.

Facial nerve palsy in posterior fossa arachnoid cysts: report of two cases.

CASE REPORT: Two patients with a posterior fossa arachnoid cyst responsible for isolated facial nerve palsy are reported. DISCUSSION: The relationships between the cyst and the facial nerve and between the facial nerve palsy and the size variation of the cyst are discussed and documented by pre- and postoperative magnetic resonance imaging.