In Reply: Middle Meningeal Artery Embolization for Primary Treatment of a Chronic Subdural Hematoma in a Pediatric Patient: A Systematic Review of the Literature and Case Report.

Abstract

To the Editor: We thank Lu et al1 for their interest in our article. Middle meningeal artery (MMA) embolization is becoming increasingly used in a subset of pediatric patients, and in the short time since the submission of our manuscript, an additional 2 case reports have been published.2,3 In their letter, Lu et al1 described several important considerations that will guide the selection of appropriate pediatric candidates for MMA embolization. Age—We agree that the age of the patient is an important factor. Among pediatric patients, chronic subdural hematomas are most commonly associated with abusive head trauma, anticoagulation/antiplatelet treatment for congenital cardiac disease, and ventricular shunt overdrainage.4 As a result, pediatric chronic subdural hematomas are often identified in infants and young children. Less common etiologies include neoplastic disease and arachnoid cysts, which can affect pediatric patients of any age. Pediatric patients at the younger end of the spectrum present several unique challenges because of the small caliber of their blood vessels, as well as the importance of limiting iodinated contrast and ionizing radiation.5 Despite these challenges, MMA embolization in young patients is feasible and can be a safe option in select patients when performed by experienced providers. Five of the 8 cases that have been described in the literature involved patients who were 2 years of age or younger.2,3,6-8 Etiology—As highlighted by Lu et al,1 2 patients in our systematic review underwent MMA embolization in the setting of a ruptured arachnoid cyst.9,10 We fully agree that subdural hygromas associated with arachnoid cysts can be treated nonsurgically11 and that even a certain subset of subdural hematomas can also be observed in this setting. As such, we agree that MMA embolization may not be the optimal first-line treatment in such cases. Indeed, both patients described in the literature only underwent MMA embolization after first undergoing either burr hole drainage or subdural-to-peritoneal shunt placement, with subsequent symptomatic recurrence of the hematoma.9,10 Timing—As alluded to above, the timing of intervention is controversial. Only 2 of the patients described in the literature underwent MMA embolization as a first-line treatment.7,12 Given the small number of cases that have been reported to date, we agree that MMA embolization is far from becoming the standard of care among pediatric patients with chronic subdural hematomas. Nevertheless, it represents yet another treatment option in the neurosurgeon's armamentarium and warrants additional study to determine its optimal role. We thank Lu et al1 for pointing out these important considerations and look forward to seeing the pediatric neurosurgical community continue to study the indications, efficacy, and risks of pediatric MMA embolization.