Even though fractures in children with immature spines occur predominantly in the upper cervical spine, isolated C-1 fractures are relatively rare. The fractures in almost all cases reported to date were considered stable due to the presence of the intact transverse ligament. The authors report the case of a young child who sustained a Jefferson fracture and in whom MR imaging revealed disruption of the transverse ligament. Although surgical treatment has been suggested as the treatment of choice for children with unstable atlantoaxial injuries, external immobilization alone allowed a full recovery in the patient with no evidence of instability at follow-up.
Marcelo D. Vilela and Eric C. Peterson
Eric C. Peterson and Roberto C. Heros
Sudheer Ambekar, Brandon G. Gaynor, Eric C. Peterson, and Mohamed Samy Elhammady
Dural arteriovenous fistulas (DAVFs) are complex lesions consisting of abnormal connections between meningeal arteries and dural venous sinuses and/or cerebral veins. The goal of treatment is surgical or endovascular occlusion of the fistula or fistulous nidus or at least the disconnection of the feeding vessels and the draining veins. Delayed angiographic data on previously embolized dural fistulas is lacking. The authors report their experience and the long-term angiographic results with embolization of intracranial DAVF using Onyx.
All cases of DAVF treated primarily with Onyx at the authors’ institution from 2006 to 2013 were retrospectively reviewed. Patient demographics, fistula characteristics, embolization details, and angiographic follow-up were analyzed.
Fifty-eight patients with DAVFs were treated during the study period. Twenty-two patients were treated with open surgery with or without prior embolization. Thirty-six patients were treated with embolization alone, of whom 26 underwent an attempt at curative embolization and are the subject of this review. All but 2 of these patients were treated in a single session. Angiographic “cure” was achieved in all cases following treatment. Follow-up angiography was performed in 21 patients at a mean of 14 months after treatment (range 2–39 months). Asymptomatic angiographic recurrence of the fistula was evident in 3 of the 21 patients (14.3%). On reviewing the procedural angiograms of the cases in which the DAVFs recurred, it was observed that the Onyx cast did not reach the venous portion in 1 case, whereas it did reach the vein in the other 2 cases.
Recurrence following initial angiographic cure of DAVF is not uncommon. Incomplete penetration of the embolic material into the proximal portion of the venous outlet may lead to delayed recurrence. Long-term angiographic follow-up is highly recommended.
Mohamed Samy Elhammady, Eric C. Peterson, and Mohammad Ali Aziz-Sultan
The treatment of indirect carotid cavernous fistulas (CCFs) is challenging and primarily accomplished by endovascular means utilizing a variety of embolic agents. Transvenous access to the cavernous sinus is the preferred method of embolizaiton of indirect CCFs as they are frequently associated with numerous small-caliber meningeal branches. Although the inferior petrosal sinus is the simplest, shortest, and most commonly used venous route to the cavernous sinus, the superior ophthalmic vein, superior petrosal sinus, basilar plexus, and pterygoid plexus present other endovenous options. Occasionally, however, use of these venous routes may not be possible due to vessel tortuosity or sinus thrombosis and occlusion.
The authors report a case of an indirect CCF that could not be treated endovascularly due to inability to access the cavernous sinus via a transfemoral transvenous approach. Angiography revealed a small, deeply located superior ophthalmic vein that was thought to be suboptimal for a direct cutdown. The cavernous sinus was cannulated directly via a transorbital approach using fluoroscopic guidance with a 3D skull reconstruction overlay. The fistula was subsequently obliterated using ethylene vinyl alcohol copolymer (Onyx). The technique and advantages of both 3D osseous reconstruction as well as Onyx embolization are discussed.
Eric C. Peterson and Roberto Heros
Part 1: Response to insult caused by arterial hypertension
Eric W. Peterson and Erico R. Cardoso
✓ In three groups of cats, the authors studied the effect of subarachnoid hemorrhage (SAH) on the permeability of the blood-brain barrier (BBB) to the penetration of Evans blue-protein complex. One group received arterial hypertension alone, one group SAH alone, and one group SAH followed by arterial hypertension. Animals subjected to arterial hypertension alone showed areas of BBB breakdown. However, when cats were rendered hypertensive after SAH, there were no demonstrable BBB lesions. The SAH was produced by intracisternal injection of whole blood and hypertension by the intravenous injection of metaraminol. The preservation of the BBB after SAH is discussed. Vasospasm is considered as a possible hemodynamic variable responsible for the protection of the BBB from hypertensive damage. The need for a new model is proposed to further investigate the state of the BBB after SAH.
Part 2: Response to mercuric chloride infusion
Eric W. Peterson and Erico R. Cardoso
✓ Under controlled physiological conditions, fresh blood was injected into the cisterna magna of 10 adult cats to produce subarachnoid hemorrhage (SAH). Damage to the blood-brain barrier (BBB) was induced 30 minutes after SAH by the intracarotid injection of a 6 × 10−5M solution of mercuric chloride (HgCl2). A control series of five cats received the same injection of HgCl2. Intravenously injected Evans blue dye was used to indicate areas of BBB damage. The lesions were confirmed by fluorescence microscopy. All control animals showed BBB damage in the hemisphere injected with HgCl2. Of the animals in the test group with SAH, 90% were free from lesions. When lesions were present, the distribution differed from that in the control group. These results bear a similarity to the reported absence of HgCl2 lesions during the acute stages after total cerebral ischemia. This suggests that the cellular components of the BBB participate in a general metabolic inhibition following SAH.
Joaquin E. Jimenez, Zachary C. Gersey, Jason Wagner, Brian Snelling, Sudheer Ambekar, and Eric C. Peterson
Pediatric patients are at risk for the recurrence of brain arteriovenous malformation (AVM) after resection. While there is general consensus on the importance of follow-up after surgical removal of an AVM, there is a lack of consistency in the duration of that follow-up. The object of this systematic review was to examine the role of follow-up imaging in detecting AVM recurrence early and preventing AVM rupture.
This systematic review was performed using articles obtained through a search of the literature contained in the MeSH database, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.
Search results revealed 1052 articles, 13 of which described 31 cases of AVM recurrence meeting the criteria for inclusion in this study. Detection of AVM occurred significantly earlier (mean ± SD, 3.56 ± 3.67 years) in patients with follow-up imaging than in those without (mean 8.86 ± 5.61 years; p = 0.0169). While 13.34% of patients who underwent follow-up imaging presented with rupture of a recurrent AVM, 57.14% of those without follow-up imaging presented with a ruptured recurrence (p = 0.0377).
Follow-up imaging has an integral role after AVM resection and is sometimes not performed for a sufficient period, leading to delayed detection of recurrence and an increased likelihood of a ruptured recurrent AVM.
Sumedh S. Shah, Zachary C. Gersey, Mohamed Nuh, Hesham T. Ghonim, Mohamed Samy Elhammady, and Eric C. Peterson
Blood-blister aneurysms (BBAs) of the internal carotid artery (ICA) have a poor natural history associated with high morbidity and mortality. Currently, both surgical and endovascular techniques are employed to treat BBAs; thus, the authors sought to perform a meta-analysis to compare the efficacy and safety of these approaches.
A literature search of PubMed, MEDLINE, and Google Scholar online databases was performed to include pertinent English-language studies from 2005 to 2015 that discussed the efficacy and safety of either surgical or endovascular therapies to treat BBAs.
Thirty-six papers describing 256 patients with BBAs treated endovascularly (122 procedures) or surgically (139 procedures) were examined for data related to therapeutic efficacy and safety. Pooled analysis of 9 papers demonstrated immediate and late (mean 20.9 months) aneurysm occlusion rates of 88.9% (95% CI 77.6%–94.8%) and 88.4% (95% CI 76.7%–94.6%), respectively, in surgically treated patients. Pooled analysis of 12 papers revealed immediate and late aneurysm obliteration rates of 63.9% (95% CI 52.3%–74.1%) and 75.9% (95% CI 65.9%–83.7%), respectively, in endovascularly treated aneurysms. Procedure-related complications and overall poor neurological outcomes were slightly greater in the surgically treated cases than in the endovascularly treated cases (27.8% [95% CI 19.6%–37.8%] vs 26.2% [95% CI 18.4%–35.8%]), indicating that endovascular therapy may provide better outcomes.
Blood-blister aneurysms are rare, challenging lesions with a poor prognosis. Although surgical management potentially offers superior aneurysm obliteration rates immediately after treatment and at the long-term follow-up, endovascular therapy may have a better safety profile and provide better functional outcomes than surgery. A registry of patients treated for BBAs may be warranted to better document the natural course of the disease as well as treatment outcomes.