Localization of Maxillary Artery for Cerebral Revascularization: L-Shaped Perpendicular Two-Step Drilling Technique Stretching from the Foramen Ovale to Rotundum.

BACKGROUND: The use of the maxillary artery (MA) as a donor has increasingly become an alternative method for cerebral revascularization. Localization difficulties emerge due to rich infratemporal anatomical variations and the complicated relationships of the MA with neuromuscular structures. We propose an alternative localization method via the interforaminal route along the middle fossa floor. METHODS: Five silicone-injected adult cadaver heads (10 sides) were dissected. Safe and effective localization of the MA was evaluated. RESULTS: The MA displayed anatomical variations in relation to the lateral pterygoid muscle (LPM) and the mandibular nerve branches. The proposed L-shaped perpendicular 2-step drilling technique revealed a long MA segment that allowed generous rotation to the intracranial area for an end-to-end anastomosis. The first step of drilling involved medial-to-lateral expansion of foramen ovale up to the lateral border of the superior head of the LPM. The second step of drilling extended at an angle approximately 90° to the initial path and reached anteriorly to the foramen rotundum. The MA was localized by gently retracting the upper head of the LPM medially in a posterior-to-anterior direction. CONCLUSIONS: Considering all anatomical variations, the L-shaped perpendicular 2-step drilling technique through the interforaminal space is an attainable method to release an adequate length of MA. The advantages of this technique include the early identification of precise landmarks for the areas to be drilled, preserving all mandibular nerve branches, the deep temporal arteries, and maintaining the continuity of the LPM.

Maxillary Nerve as Landmark for Exposure of the Internal Maxillary Artery in Extracranial-Intracranial Bypass Surgery.

OBJECTIVE: To establish a new method for fast exposure of the internal maxillary artery (IMA) during extracranial-intracranial bypass surgery. METHODS: To explore the positional relationship between the IMA and the maxillary nerve and pterygomaxillary fissure, 11 formalin-fixed cadaveric specimens were dissected. Three bone windows of the middle fossa were created for further analysis. Then the IMA length that could be pulled up above the middle fossa was measured after different degrees of removal of bony structure. The IMA branches under each bone window were also explored in detail. RESULTS: The top of the pterygomaxillary fissure was located 11.50 mm anterolateral to the foramen rotundum. The IMA could be identified just inferior to the infratemporal segment maxillary nerve in all specimens. After drilling of the first bone window, the IMA length that could be pulled above the middle fossa bone was 6.85 mm. After drilling of the second bone window and further mobilization, the IMA length that could be harvested was significantly longer (9.04 mm vs. 6.85 mm; P < 0.001). Removal of the third bone window did not significantly improve the IMA length that could be harvested. CONCLUSIONS: The maxillary nerve could be used as a reliable landmark for the exposure of the IMA in the pterygopalatine fossa. With our technique, the IMA could be easily exposed and sufficiently dissected without zygomatic osteotomy and extensive middle fossa floor removal.

Endoscope-Assisted Pedicled Maxillary Artery to Middle Cerebral Artery Bypass: An Anatomic Feasibility Study.

BACKGROUND: Extracranial to intracranial bypass is used to augment and/or replace the intracranial circulation for various pathologies. The superficial temporal artery is the mainstay donor for pedicled bypasses to the anterior circulation but can be limited by its variable size, low native flow rates, and potential scalp complications. Interposition grafts such as the radial artery or greater saphenous vein are alternatives but are sometimes limited by size mismatch, length needed to reach the extracranial circulation, and loss of inherent vascular elasticity. Interposition grafts between the maxillary artery (IMA) and middle cerebral artery (MCA) address these limitations. OBJECTIVE: To explore the feasibility of harvesting the IMA through an endoscopic transnasal, transmaxillary approach to perform a direct IMA to MCA bypass. METHODS: Combined transcranial and endoscopic endonasal dissections were performed in embalmed human cadavers to harvest the IMAs for intracranial transposition and direct anastomosis to the MCA. Donor and recipient vessel calibers were measured and recorded. RESULTS: A total of 8 procedures were performed using the largest and distal-most branches of the IMA (the sphenopalatine branch and the descending palatine branch) as pedicled conduits to second division of middle cerebral artery (M2) recipients. The mean diameter of the IMA donors was 1.89 mm (SD ± 0.42 mm), and the mean diameter of the recipient M2 vessels was 1.90 mm (SD ± 0.46 mm). CONCLUSION: Endoscopic harvest of the IMA using a transnasal, transmaxillary approach is a technically feasible option offering an excellent size match to the M2 divisions of the MCA and the advantages of a relatively short, pedicled donor vessel.

How I do it: internal maxillary artery to middle cerebral artery bypass to manage giant thrombosed internal carotid artery aneurysm.

BACKGROUND: Internal maxillary artery (IMA) bypass has become popularized due to its medium-to-high blood flow, short graft length, and well-matched arterial caliber between donor and recipient vessels. METHOD: We described an open surgery of a NEW "workhorse," the IMA bypass, to treat a giant, thrombosed cerebral aneurysm. The extracranial middle infratemporal fossa (EMITF) approach was used to unveil the pterygoid segment of the IMA for cerebral revascularization. CONCLUSION: Although this technique is technically challenging, the variations in IMA can be effectively identified and sufficiently exposed in this technique to achieve favorable clinical outcomes with a high bypass patency rate.

[Extra-intracranial bypass surgery using the orifice of maxillary artery in a patient with middle cerebral artery aneurysm. Case report and literature review]. / Pervyi opyt vypolneniya ekstra-intrakranial'nogo shuntirovaniya s ispol'zovaniem ust'ya verkhnechelyustnoi arterii u patsienta s anevrizmoi srednei mozgovoi arterii. Opisanie klinicheskogo sluchaya i obzor literatury.

OBJECTIVE: To present the technique of extra-intracranial bypass surgery using the orifice of maxillary artery bypass, to evaluate the advantages and disadvantages of this and alternative revascularization options. MATERIAL AND METHODS: Radial artery graft harvesting was performed at the 1st stage. Simultaneously, the second team of surgeons performed a combined (submandibular and anterior) access to the donor artery (mandibular segment of maxillary artery behind the ramus of the mandible). Craniotomy and mobilization of potential recipient arteries (M2-M3 segments of the middle cerebral artery) were performed at the 2nd stage. Distal anastomosis in end-to-side fashion was formed with M3 segment of the middle cerebral artery. At the 3rd stage, radial artery was passed through a subcutaneous tunnel in zygomatic region. The orifice of maxillary artery was resected together with distal external carotid artery (ECA) and orifice of superficial temporal artery. After transposition of ECA and orifice of maxillary artery, proximal end-to-end anastomosis was performed with radial artery. After that, the main surgical stage was performed, i.e. exclusion of M3 segment of the middle cerebral artery together with aneurysm. RESULTS: Harvesting of mandibular segment of the maxillary artery as a donor vessel reduces the length of bypass graft to 12-14 cm since this branch is localized close to the skull base. You can also form optimal proximal end-to-end anastomosis for intracranial redirecting blood flow maxillary artery. CONCLUSION: The described method makes it possible to form anastomosis with a short bypass graft and reduce the risk of thrombosis. This procedure is effective for cerebral bypass in patients with skull base tumors, complex aneurysms, and occlusive-stenotic lesions of carotid arteries.

Computed Tomography Perfusion Imaging Study of Intracranial Complex Aneurysms Treated by Internal Maxillary Artery Bypass Grafting.

BACKGROUND: Cerebral revascularization strategies through extracranial to intracranial bypass have been adopted in the management of complex intracranial aneurysms. The internal maxillary artery used as a donor in a bypass is an effective method. At present, there are few quantitative analyses of cerebral blood flow perfusion. The main focus of this study was to evaluate the effectiveness of blood perfusion after bypass grafting. METHODS: From April 2015 to December 2017, 19 patients who underwent internal maxillary artery radial artery middle cerebral artery bypass surgery with unobstructed bypass vessels were selected. Cerebral blood flow perfusion before and after bypass surgery was quantitatively evaluated by computed tomography perfusion imaging. The cerebral blood perfusion in the region of interest was measured by computed tomography perfusion. RESULTS: The aneurysms were excised after trapping in 2 cases with mass effects and neural compression. Proximal occlusion of the parent artery was performed in 9 cases of fusiform or giant dissecting aneurysms. Trapping was performed after bypass surgery in 8 cases. Within 3 months after surgery, 17 patients had good outcomes. After the hypothesis test, there was a significant difference between the preoperative △cerebral blood volume and postoperative △cerebral blood volume in the anterior area of the semioval center cross section (P = 0.001 < 0.05). CONCLUSIONS: The internal maxillary artery as a bypass donor is an effective method that can provide sufficient intracranial blood perfusion, and there is usually no cerebral ischemia in the surrounding area.

Preoperative Arterial Coil Embolization for Temporomandibular Joint (TMJ) Surgery in Children with TMJ Ankylosis.

ABSTRACT: Temporomandibular joint (TMJ) ankylosis in children can alter facial development and affect oral hygiene and function. Surgical release of the ankylosis is the mainstay of treatment. The authors hypothesize that preoperative arterial coil embolization is safe and effective in preventing major blood loss during TMJ surgery (loss prompting blood transfusion or hemodynamic instability requiring vasoactive medication administration) in children with TMJ ankylosis. Patients < 16 years who were diagnosed with TMJ ankylosis (<15 maximal interincisal opening) and had embolization before surgery in the last 5 years were included. Out of 9 initial search results, 3 patients were excluded (age > 16). Information gathered were patient demographics, diagnostic imaging, procedural details, complications, and clinical outcomes. Six patients, mean age 11.14 years (range 7-15 years) year and a mean weight of 40.8 ± 19 kg were included. Underlying etiologies for TMJ ankylosis: Pierre Robin Syndrome (n = 2), juvenile rheumatoid arthritis (n = 1), Goldenhar's syndrome (n = 1), trauma (n = 1), and micrognathia (n = 1). Neck computed tomography angiogram before embolization demonstrated an intimate approximation between the internal maxillary artery (IMAX) and/or external carotid artery and ankylotic mass in all patients. Eight successful embolizations were performed without procedural complication. In 1 patient with angiographic evidence of surgical internal maxillary artery ligation, embolization was performed via collaterals. Surgery was performed within 48 hours of embolization. Airway access during surgery was via nasal intubation (n = 4), oral intubation (n = 3). The estimated blood loss (EBL) during surgery was 78.33 ± 47.08 ml. Three patients had subsequent TMJ surgery with a mean estimated blood loss of 73.33 ± 46.18 ml. After a mean follow-up of 17 ± 15 months, patients showed a 13.8mm mean increment of maximal interincisal opening with 95% CI (5.74-21.9), P < 0.007.

Internal maxillary artery to middle cerebral artery bypass for a complex recurrent middle cerebral artery aneurysm: case report and technical considerations.

We report the case of a 41-year-old male who presented with an enlarging aneurysm neck one year after clipping. The patient underwent an IMAX-MCA bypass followed by endovascular coil occlusion of the aneurysm neck incorporating an MCA branch origin. To our knowledge, this case represents the first documented IMAX-MCA bypass from a European centre. This case demonstrates that for neurosurgeons experienced in EC-IC bypass surgery, IMAX-MCA bypass is feasible and can be performed safely as long as careful attention is paid to anatomical landmarks and vascular anastomosis principles. CTA-based neuronavigation and micro-Doppler are essential intraoperative tools for identifying the IMAX.

Cauterización transoral de la arteria maxilar interna en la fosa infratemporal: informe de un caso / Transoral cauterization of the internal maxillary artery in the infratemporal fossa: case report

Se describe el caso clínico de una paciente de 84 años que tuvo epistaxis recidivante por padecer enfermedad de Rendu-Osler-Weber. Tuvo antecedentes de diversos tratamientos quirúrgicos que incluyeron el cierre de la fosa nasal izquierda (operación de Young). Por la persistencia de epistaxis izquierda se indicó una angiografía y embolización. Esta última no se hizo porque se diagnosticaron anastomosis entre el sistema carotídeo externo y el interno. Se realizó un abordaje intraoral paramaxilar asistido con endoscopios para cauterizar la arteria maxilar interna en la fosa infratemporal y un abordaje externo para cauterizar la arteria etmoidal anterior solucionando la epistaxis. (AU)

The clinical case of an 84-year-old patient who had recurrent epistaxis due to Rendu-Osler- Weber disease is described. She had a history of various surgical treatments including closure of the left nostril (Young's operation).Due to the persistence of left epistaxis, angiography and embolization were indicated. The latter was not done because anastomosis between the external and internal carotid system was diagnosed. An intraoral paramaxillary approach assisted with endoscopes was performed to cauterize the internal maxillary artery in the infratemporal fossa and an external approach to cauterize the anterior ethmoidal artery solving the epistaxis. (AU)

Pseudoaneurysm of the Maxillary Artery With Prebleeding Warning Signs After Le Fort I Osteotomy.

ABSTRACT: Epistaxis after Le Fort I osteotomy is one of the relatively common postoperative complications. It can be controlled with conservative treatment, such as nasal packing, and will usually improve in a few days. However, if the epistaxis is repeated, the outcome can be life-threatening. A 22-year-old woman underwent Le Fort I osteotomy in order to correct her malocclusion. Postoperatively, pseudoaneurysm was formed in the descending palate artery, causing repeated epistaxis. Then, angiography and embolization were performed. Before the onset of epistaxis, there was discomfort around the nasal area. The patient remained asymptomatic during the 6-month follow-up. Some epistaxis after Le Fort I osteotomy is due to pseudoaneurysm formation in the maxillary artery. It is very rare. The epistaxis is delayed and recurrent. It can cause massive bleeding, and so, requires proper diagnosis and treatment. There may be signs of bleeding as in this case.

Endoscopic transorbital ligation of the maxillary artery through the inferior orbital fissure.

OBJECTIVE: Determine the feasibility of accessing the internal maxillary artery (IMA) through a transorbital endoscopic assisted approach through the inferior orbital fissure (IOF). MATERIALS AND METHODS: Six adult cadaveric specimens were injected intravascularly with colored latex and dissected on 12 sides. A transorbital endoscopic approach was used to expose the IOF and reach the IMA. RESULTS: The average length and width of the anterolateral segment of the IOF were 7.3 and 4 mm, respectively, on the right side and 6.7 and 3.8 mm, respectively, on the left side. Surgical exposure and modification of the IOF allowed the exposure and control of the IMA in all 12 sides. CONCLUSIONS: The IOF is a feasible portal to the IMA. The benefits of this approach include vascular control of the distal segment of the maxillary artery. It may provide access in clinical scenarios where endonasal access is not possible (e.g., extensive tumors) or serve as an alternative or complementary surgical route (e.g., control during a total or radical maxillectomy).

Delayed Bleeding of Sphenopalatine Artery as a Complication in Le Fort I Osteotomy.

ABSTRACT: Rates of severe complications in orthognathic surgery are low, but when they occur they can be fatal. This article reports a case of laceration of the junction of the posterior lateral nasal artery and the sphenopalatine artery, resulting in severe delayed bleeding. Patient undergoes a multiple segment Le Fort I osteotomy with no intraoperative or immediate postoperative complications. On the fourth postoperative day, he presents with epistaxis and intractable postnasal discharge, is admitted to emergency with signs of shock, and bleeding is detected endoscopically originating from the right sphenopalatine artery, which is treated with diathermocoagulation. The advantage of endoscopy in difficult areas is that bleeding complications can be solved with low morbidity.

Pterygo-Maxillary Fissure as a Landmark for Localization of Internal Maxillary Artery for Use in Extracranial-Intracranial Bypass.

BACKGROUND: Internal maxillary artery (IMax) is a relatively new donor vessel used in the extracranial-intracranial bypass surgery. However, unfamiliarity and relatively elaborate techniques of its harvest precluded its widespread use. OBJECTIVE: To present a simplified technique of IMax harvest based on constant anatomical landmarks without the need of extensive skull-base drilling while providing adequate space for proximal anastomosis. METHODS: Cadaveric dissection on 4 cadaveric heads (8 sides) was performed. Zygomatic osteotomy was performed and temporal muscle was dissected off the zygomatic process of the frontal bone and the frontal process of the zygomatic bone and reflected inferiorly into the bony gap created by the zygomatic osteotomy. Posterior wall of the maxilla (PWoM) was palpated. Following PWoM inferiorly leads to pterygo-maxillary fissure (PMF), which is a constant landmark IMax passes through. RESULTS: IMax was localized following this technique before its entrance into PMF in every specimen. Proximal dissection was carried on to the exposed adequate length of the vessel. Depending on the relationship with the lateral pterygoid muscle, this might need to be incised to allow for identification of the IMax. After its transection, proximal stump is mobilized superiorly into the surgical field. Clinical application of this technique was demonstrated on an aneurysm case. CONCLUSION: Using the palpation of the PWoM as a landmark for localization of PMF facilitates harvesting of IMax without need for extensive skull-base drilling and shortens the time of the surgery.

Arterial Embolization and Second-Look in Spindle Cell Oncocytoma of the Pituitary Gland: Case Report and Review of Literature.

BACKGROUND: Spindle cell oncocytomas are extremely rare neoplasms of the sellar, parasellar, and suprasellar regions that can frequently mimic pituitary adenomas. Fewer than 50 cases have been ever reported in the literature, and there is no consensus on best treatments to be provided. CASE DESCRIPTION: We hereby present a challenging case of sellar and suprasellar spindle cell oncocytoma in a patient of 64 years. The patient, who presented with hydrocephalus, hypopituitarism, and visual deficit, underwent urgent transsphenoidal (TNS) resection of the mass, which was aborted for massive life-threatening bleeding. The patient received ventriculoperitoneal shunt with relief of symptoms. An endovascular embolization of tumor feeders from the distal portion of the right internal maxillary artery, in particular the sphenopalatine artery, was then performed and a second-look TNS surgery was feasible. The patient was discharged in optimal clinical condition, recovered both endocrinologic and visual deficits, and is now in follow-up. CONCLUSIONS: We found that the oncocytoma was radiologically and clinically comparable with a pituitary adenoma, except for higher representation of vasculature. According to our recent experience and review of the literature, we believe that surgery (transsphenoidal or transcranial approach) is the recommended treatment in those who are symptomatic and preoperative embolization might be a suitable option to reduce intraoperative bleeding and increase radicality.

Estudio de la anastomosis del conducto alveolar superior anterior y posterior en pacientes con fisura labiopalatina / Prevalence of posterior superior alveolar canal anastomosis with anterior superior alveolar canal in patients with cleft lip and palate

OBJETIVOS: Describir la prevalencia y localización de la anastomosis intraósea (AIO) del conducto alveolar superior posterior (CASP) con el conducto alveolar superior anterior (CASA) en pacientes portadores de fisura labiopalatina, comparando el lado afectado por la fisura labiopalatina de tipo transforamen incisivo unilateral (FLP) con el contralateral no portador de fisura labiopalatina (NF). MATERIAL y MÉTODO: Fueron evaluadas 1500 tomografías computadorizadas de haz cónico (TCHC) y de acuerdo con criterios de inclusión, 95 TCHC fueron seleccionadas para análisis (52 hombres, 43 mujeres, edad media 27 años). La muestra fue conformada por: 1) pacientes con FLP en el lado derecho y NF en el lado izquierdo; y 2) pacientes con FLP en el lado izquierdo y NF en el lado derecho. El análisis fue dividido en 4 etapas: 1) calibración intra e interexaminador; 2) evaluación de la presencia/ausencia de la AIO del CASP con CASA; 3) localización de la AIO del CASP con CASA, tomando como referencia las caras mesiales de los dientes (17/27), (16/26), (15/5) y (14/24); y 4) comparar la simetría/asimetría de localización comparando el lado portador de FLP con el contralateral NF. RESULTADOS: La prevalencia total de la AIO fue de 67,9 %. La prevalencia de la AIO en el lado portador de FLP fue 71,6 % y en el lado NF fue 64,2 % (Test de Fisher > 0,35). La localización de la AIO en el lado portador de FLP fue más prevalente en las áreas (15/25), (16/26) y en el lado NF fue en el área (14/24) (Test Chi-cuadrado < 0.03). La AIO es asimétrico en el 71,5 % (Test de Fisher < 0.03), cuando se compara el lado FLP con el contralateral NF. CONCLUSIONES: La prevalencia de la AIO fue mayor en el lado portador de FLP (71,6 %) comparado con el lado NF (64,2 %). La localización de AIO en el lado portador de FLP fue dislocado hacia distal a diferencia de su contralateral NF. La AIO fue asimétrica en 71,5 % de los casos. Esta información es relevante en procedimientos quirúrgicos que son realizados en pacientes con fisuras labiopalatinas, que tienen por objetivo corregir las discrepancias maxilomandibulares

OBJECTIVES: The purpose of this study was to examine the prevalence of intraosseous anastomosis (AIO) between the posterior superior alveolar canal (CASP) and the anterior superior alveolar canal (CASA) in patients with cleft lip and palate, comparing the side affected by unilateral incisive trans-forame fissure (FLP) with the contralateral side not affected by fissure (NF). Material and method: A total of 1500 Cone Beam Computed Tomography (TCHC) were evaluated and, according to inclusion criteria, 95 TCHC were selected for analysis (52 men, 43 women, average age 27 years). The sample consisted of 1) patients with FLP on the right side and NF on the left side; and 2) patients with FLP on the left side and NF on the right side. The analysis was divided into 4 steps: 1) Intra and inter-rater calibration; 2) evaluating presence or absence of AIO anastomose between the CASP with CASA; 3) Location of the AIO anastomose between the CASP with CASA, as reference to the mesial aspect of each tooth (17/27), (16/26), (15/25) and (14/24); 4) Evaluated symmetry/asymmetry the localization of AIO, comparing them side with FLP, with the contralateral side NF. RESULTS: The total prevalence of AIO was 67.9 %. The prevalence in FLP side was 71.6 %, and NF side was 64.2 % (Fisher's test > 0.35). The location of the AIO in the FLP side was more than prevalent in the areas of (15/25), (16/26) and on the NF side, it was in the area (14/24) (Chi-square test < 0.03). The AIO was 71.5% (Fisher's test > 0.03) asymmetric comparative of the FLP side with the contralateral NF. CONCLUSIONS: The prevalence of AIO was higher in FLP side (71.6 %) comparing the NF side (64.2 %). The location of AIO, in the FLP side was dislocated distally when compared with the contralateral side NF. The AIO was asymmetric in 71.5% of the cases. This information is relevant in surgical procedures that are performed in patients with cleft lip and palate, which aim to correct maxillomandibular discrepancies

Surgical Anatomy of the Donor Arteries for Extracranial-Intracranial Bypass Surgery: An Anatomic and Radiologic Study.

OBJECTIVE: To review the microsurgical anatomy of the donor arteries for extracranial-intracranial bypass, namely, the superficial temporal artery (STA), occipital artery (OA), and internal maxillary artery (IMA). METHODS: Seven cadaveric specimens were dissected to identify the relationships between each artery and its surrounding structures. Nineteen computed tomographic angiographic images of Japanese adult patients (38 sides) were analyzed to examine the course of each artery and to measure the diameters and distances from various anatomic landmarks to each artery. RESULTS: The courses of the STA, OA, and IMA, which must be exposed during revascularization procedures, were shown via cadaver dissection with special reference to the following relationships to surrounding structures: STA, soft tissue layers of the temporoparietal region and facial nerve; OA, suboccipital muscles; and IMA, mandibular nerve. In addition, we measured the diameter of the anastomotic site for each artery and its relationship with surrounding muscles. CONCLUSIONS: A precise understanding of the anatomic characteristics of the donor arteries and their relationships with surrounding structures provides safe access to these arteries.

Endosteal blood supply of the mandible: anatomical study of nutrient vessels in the condylar neck accessory foramina.

PURPOSE: In the mandible, the condylar neck vascularization is commonly described as mainly periosteal; while the endosteal contribution is still debated, with very limited anatomical studies. Previous works have shown the contribution of nutrient vessels through accessory foramina and their contribution in the blood supply of other parts of the mandible. Our aim was to study the condylar neck's blood supply from nutrient foramina. METHODS: Six latex-injected heads were dissected and two hundred mandibular condyles were observed on dry mandibles searching for accessory bone foramina. RESULTS: Latex-injected dissections showed a direct condylar medular arterial supply through foramina. On dry mandibles, these foramina were most frequently observed in the pterygoid fovea in 91% of cases. However, two other accessory foramina areas were identified on the lateral and medial sides of the mandibular condylar process, confirming the vascular contribution of transverse facial and maxillary arteries. CONCLUSIONS: The maxillary artery indeed provided both endosteal and periosteal blood supply to the condylar neck, with three different branches: an intramedullary ascending artery (arising from the inferior alveolar artery), a direct nutrient branch and some pterygoid osteomuscular branches.