Endovascular Management of Iatrogenic Pseudoaneurysm of Internal Maxillary Artery after Dental Extraction

Pseudoaneurysm developing from the internal maxillary artery is a rare but potentially fatal condition. We describe a case of iatrogenic pseudoaneurysm of the internal maxillary artery developed during dental extraction and successful endovascular closure of the feeder artery. At 2-month follow-up, the patient remained well with persistent thrombosis of pseudoaneurysm.

Preoperative Endovascular Embolization of Glomus Jugulare Tumors: A Retrospective Case Series of 22 Embolizations in 20 Patients and Literature Review

Objective Glomus jugulare tumors, or tympanojugular paragangliomas, are rare, highly vascularized skull base tumors originated from paraganglion cells of the neural crest. With nonabsorbable embolic agents, embolization combined with surgery has become the norm. The authors assess the profile and outcomes of patients submitted to preoperative embolization in a Brazilian tertiary care hospital. Methods The present study is a single-center, retrospective analysis; between January 2008 and December 2019, 22 embolizations were performed in 20 patients in a preoperative character, and their medical records were analyzed for the present case series. Results Hearing loss was the most common symptom, present in 50% of the patients, while 40% had tinnitus, 30% had dysphagia, 25% had facial paralysis, 20% had hoarseness, and 10% had diplopia. In 7 out of 22 embolization procedures (31%) more than a single embolic agent was used; Gelfoam (Pfizer, New York, NY, USA) was used in 18 procedures (81%), in 12 of which as the single agent, followed by Embosphere (Merit Medical, South Jordan, UT, USA) (31%), Onyx (Medtronic, Minneapolis, MN, USA) (9%), and polyvynil alcohol (PVA) and Bead Block (Boston Scientific, Marlborough, MA, USA) in 4,5% each. The most common vessel involved was the ascending pharyngeal artery, involved in 90% of the patients, followed by the posterior auricular artery in 15%, the internal maxillary artery or the occipital artery in 10% each, and the superficial temporal or the lingual arteries, with 6% each. Only one patient had involvement of the internal carotid artery. No complications from embolization were recorded. Conclusions Preoperative embolization of glomus tumors is safe and reduces surgical time and complications, due to the decrease in size and bleeding.

A Novel Thromboplastin-Based Rat Model of Ischemic Stroke

The thromboembolic ischemia model is one of the most applicable for studying ischemic stroke in humans. The aim of this study was to develop a novel thromboembolic stroke model, allowing, by affordable tools, to reproduce cerebral infarction in rats. In the experimental group, the left common carotid artery, external carotid artery, and pterygopalatine branch of maxillary artery were ligated. A blood clot that was previously formed (during a 20 min period, in a catheter and syringe, by mixing with a thromboplastin solution and CaCl2) was injected into the left internal carotid artery. After 10 min, the catheter was removed, and the incision was sutured. The neurological status of the animals was evaluated using a 20-point scale. Histological examination of brain tissue was performed 6, 24, 72 h, and 6 days post-stroke. All groups showed motor and behavioral disturbances 24 h after surgery, which persisted throughout the study period. A histological examination revealed necrotic foci of varying severity in the cortex and subcortical regions of the ipsilateral hemisphere, for all experimental groups. A decrease in the density of hippocampal pyramidal neurons was revealed. Compared with existing models, the proposed ischemic stroke model significantly reduces surgical time, does not require an expensive operating microscope, and consistently reproduces brain infarction in the area of the middle cerebral artery supply.

Abstract 1122‐000148: Rare Anterior Inferior Cerebellar Artery Origin of Middle Meningeal Artery

Introduction : Middle meningeal artery (MMA) anatomy has very important surgical implications during endovascular and open based skull procedures. Various anatomical origins have been identified in the literature besides its most common origin as the largest branch of the maxillary artery. It runs parallel and close contact of the lateral skull face therefore during trauma to this area is prone to rupture resulting in subdural hemorrhage(SDH). In our case report, we present its peculiar origin from anterior inferior cerebellar artery which has never been reported before. The origin of MMA may reflects the risk involved with embolization therapy for chronic SDH. Methods : A case of MMA originated form AICA. A literature review was conducted of reports of MMA origins. Results : A 35‐year‐old male with a history of alcohol abuse presented to the ED after falling down from the stairs. In the ED, the patient had multiple episodes of seizures along with respiratory distress therefore was intubated due to concern of airway protection. CT head showed bilateral SDH. Patient underwent diagnostic angiogram for possible bilateral embolization of MMA. During the procedure, the left MMA origin was seen from the AICA whereas the right MMA arising from the external carotid artery. Embolization of the left MMA was aborted. Patient remained intubated and was later transferred to a long term care facility. Conclusions : In the last 80 years, the anatomy of the MMA has been part of the discussion of various literature. Seeger et.al, highlighted the embryological changes manifested as anastomosis between Sphenomaxillary artery and lateral pontine artery resulting in origin of MMA from Basilar artery along with absence of foramen spinosum. Since 1973, multiple literature highlighted the origin of MMA including the lacrimal artery, ICA, ascending pharyngeal artery, opthalmic and occipital arteries. Recently, In 2011 Kuruvuilla et.al showed the origin of MMA from posterior inferior cerebellar artery. MMA clinical significance can be seen in multiple diseases. Older populations with chronic subdural hematomas, embolization of MMA has shown to be a less invasive and cost effective procedure. In patients with anterior and middle cranial fossa meningiomas embolization of MMA has been a crucial part of management. Similarly, understanding of its anatomy is also important while treating MMA aneurysm or pseudoaneurysms. In our case, the origin of middle meningeal artery from AICA has been significant as it supplies the posterior fossa structures and was not reported in the literature before, hence the procedure was aborted. This anatomical variant has shown us a new light upon embryological evolution and has helped us widen the horizons of our approach towards brain vasculature. This finding will help the future Interventionists to develop new ways of embolization of the MMA and understanding its anatomy.

Shock Index as a Predictor for Angiographic Hemostasis in Life-Threatening Traumatic Oronasal Bleeding

The objective of this retrospective study was to identify predictors of angiographic hemostasis among patients with life-threatening traumatic oronasal bleeding (ONB) and determine the threshold for timely referral or intervention. The diagnosis of traumatic, life-threatening ONB was made if the patient suffered from craniofacial trauma presenting at triage with unstable hemodynamics or required a definitive airway due to ONB, without other major bleeding identified. There were 4404 craniofacial trauma patients between January 2015 and December 2019, of which 72 (1.6%) fulfilled the diagnosis of traumatic life-threatening ONB. Of these patients, 39 (54.2%) received trans-arterial embolization (TAE), 11 (15.3%) were treated with other methods, and 22 (30.5%) were excluded. Motor vehicle accidents were the most common cause of life-threatening ONB (52%), and the internal maxillary artery was the most commonly identified hemorrhaging artery requiring embolization (84%). Shock index (SI) was significantly higher in the angiographic hemostasis group (p < 0.001). The AUC-ROC was 0.87 (95% CI, 0.88–1.00) for SI to predict angiographic hemostasis. Early recognition and timely intervention are crucial in post-traumatic, life-threatening ONB management. Patients initially presenting with SI > 0.95 were more likely to receive TAE, with the TAE group having statistically higher SI than the non-TAE group whilst receiving significantly more packed red blood cells. Hence, for patients presenting with life-threatening traumatic ONB and a SI > 0.95, TAE should be considered if preliminary attempts at hemostasis have failed.

Anatomy of the Middle Meningeal Artery

Introduction The middle meningeal artery (MMA) is an important artery in neurosurgery. As the largest branch of the maxillary artery, it provides nutrition to the meninges and to the frontal and parietal regions. Diseases, including dural arteriovenous fistula (DAVF), pseudoaneurysm, true aneurysm, traumatic arteriovenous fistula (TAVF), Moya-Moya disease (MMD), recurrent chronic subdural hematoma (CSDH), migraine, and meningioma, may be related to the MMA. The aim of the present study is to describe the anatomy of the MMA and to correlate it with brain diseases. Methods A literature review was performed using the PubMed, Scielo, Scientific Direct, Ebsco, LILACS, TripDataBase and Cochrane databases, with the following descriptors: neurosurgery, neuroanatomy, meninges and blood supply. Discussion The MMA is embedded in a cranial groove, and traumatic or iatrogenic factors can result in MMA-associated pseudoaneurysms or arteriovenous fistulas (AVFs). In hemodynamic stress, true aneurysms can develop. Arteriovenous fistulas, pseudoaneurysms, and true aneurysms can be effectively treated by endovascular or surgical removal. In MMD, the MMA plays a role in the development and in the improvement of collateral circulation. Finally, in cases of CSDH, when standard surgery and drainage fail, MMA embolization can constitute a great alternative. Conclusion The MMA is a relevant structure for the understanding of neurosurgical diseases. In conclusion, every neurosurgeon must know the anatomy of the MMA sufficiently to correlate it with the diagnosed pathology, thus obtaining treatment effectiveness and preventing brain lesion.

EquineReview

Introduction: The Equine Review highlights three recently published papers from other journals. This issue's edition describes three studies regarding the role of herpesvirus in pulmonary fibrosis in both horses and humans; the role of symmetric dimethylarginine levels in kidney function analysis in dehydrated horses and the feasibility of balloon catheter occlusion of the maxillary artery, internal and external carotid artery in standing horses.