PDF(Pubmed)
Abstract：
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.
摘要：
大头畸形定义为头围异常增加，超过给定年龄和性别的平均值两个标准偏差。我们介绍了一个16个月大的男孩患有先天性进行性大头畸形的病例，他在13个月大的时候被诊断为脑积水，被转诊到我们医院进行脑室-腹腔分流术。患者在分流后12小时出现高热性癫痫发作，紧急CT检查显示心室塌陷和右额叶硬膜下集合，提示过度引流和颅内低血压。随后的脑电图（EEG）显示了一些异常，但患者在服用抗惊厥剂后，由于没有神经症状，两天后出院。由于反复发作，患者一周后返回医院。进一步的临床检查显示颅骨突出而曲折的静脉，在左侧枕区触诊。听诊时可听到惊动和左颈动脉杂音。随后进行了MR动脉造影和静脉造影的脑部MRI，以寻找脑积水的解释。序列提示硬脑膜动静脉瘘，经证实，然后在介入血管造影期间使用线圈进行治疗。两个月后进行了第二次手术以完成栓塞，随后的影像学随访显示手术成功。颅围的测量，它的定期评估，它的演变允许通过区分原发性和继发性大头畸形的分级诊断策略，进步与否。硬脑膜动静脉瘘（DAVF）是引起大头畸形的原因，在35%的病例中与之相关。颅内DAVFs是硬脑膜动脉和硬脑膜静脉窦之间的病理性分流，脑膜静脉,或者皮质静脉.DAVFs患者可能完全无症状。症状,当存在时,可能包括神经缺陷，癫痫发作,脑积水和致命性出血.症状取决于DAVF的位置以及静脉和引流模式。除非特别搜索，否则很难在常规MRI上识别它们，特别是在技术不理想的检查的情况下。我们旨在提供一种实用的方法来确定需要进一步研究的临床线索。关于大头畸形的管理存在几个具体的协议，一旦诊断已经达到，应该仔细遵循。但需要进一步的研究来整合更多的临床和神经影像学检查结果,以便于早期诊断.
