Angiographic study of the transdural collaterals at the anterior cranial fossa in patients with Moyamoya disease.

Unlike its parietal, temporal, and occipital counterparts, the frontal lobe has a broad basal surface directly facing the anterior cranial fossa dura mater which could permit establishment of transdural collaterals (TDCs) with the frontal lobe. Studies on the TDCs from the anterior cranial fossa in moyamoya disease (MMD) are scarce and inadequately investigated. A retrospective study of 100 hemispheres in 50 patients who were diagnosed with MMD by catheter angiography between January 2015 and June 2019 was performed in our institution. TDCs through the anterior ethmoid artery (AEA) or posterior ethmoid artery (PEA) were divided into 3 types respectively based on their respective angioarchitecture. Furthermore, we also studied TDCs to the temporal, parietal, and occipital lobes and collaterals from the posterior circulation to the territory of the anterior cerebral artery. TDCs through the AEA and PEA were identified in 89 (89/100, 89%) and 73 (73/100, 73%) of the hemispheres. The vascularization state of the frontal lobe was good in 89 (89/100, 89%) hemispheres. Rete mirabile and TDCs through the PEA were statistically different among patients with different Suzuki stages. No statistical difference was noted in TDCs through the AEA, frontal TDCs from other sources, and the vascularization state of the frontal lobe with regard to different Suzuki stages. TDCs through the AEA and PEA at the anterior cranial fossa play a very important role in compensating the ischemic frontal lobe. The frontal lobe could be well compensated in most of the patients with TDCs at the anterior cranial fossa.

Brainstem Venous Congestion Caused by Perimedullary Drainage in Anterior Cranial Fossa Dural Arteriovenous Fistula.

BACKGROUND: Myelopathy develops relatively rarely in intracranial dural arteriovenous fistula (DAVF); it has only been reported in posterior cranial fossa DAVF. Herein, we report the first, to our knowledge, case of anterior cranial fossa (ACF) DAVF with myelopathy. CASE DESCRIPTION: A 75-year-old man presented with dizziness, nausea, and gait disturbance. T2-weighted magnetic resonance imaging revealed a hyperintense area in the left cerebellum and medulla; a flow void was also detected around the medulla. The patient was first diagnosed with spinal DAVF, but the shunt point was detected at the anterior ethmoidal artery, flowing from the olfactory vein to the basal vein of Rosenthal and anterior/posterior spinal veins. The shunt point was clipped during craniotomy, and neurologic symptoms improved. CONCLUSIONS: Myelopathy because of intracranial DAVF potentially involves diagnostic pitfalls. Even in ACF DAVF, there is a possibility of myelopathy caused by perimedullary venous drainage.

Endovascular and surgical approaches of ethmoidal dural fistulas: a multicenter experience and a literature review.

Ethmoidal dural arteriovenous fistulae are rare vascular malformations associated with a high risk of bleeding. We present a multicenter contemporary series of patients treated with microsurgical and endovascular techniques. Sixteen consecutive patients were evaluated and/or treated between 2008 and 2015 at four centers with large experience in the endovascular and surgical treatment of cerebrovascular diseases. We analyzed demographic and clinical data, risk factors for dural fistulas, treatment type, peri- and post-operative morbidity, clinical and radiological outcomes, rates of occlusion, and long-term neurological outcome. Sixteen patients (81 % men, mean age of 58 years) with ethmoidal dural fistulas were included in the analysis. Seven patients had suffered an intracranial hemorrhage; the remaining presenting with neurological signs and symptoms or the fistula was an incidental finding. Three patients were managed conservatively. Among patients who underwent intervention (n = 13), 46.1 % were treated with endovascular therapy and 53.9 % were treated surgically. Complete angiographic obliteration was achieved in 100 % immediately after treatment and at last follow-up evaluation. All patients experienced a favorable neurological recovery (mRS 0-2) at the last follow-up visit (12 months). Ethmoidal dural AVFs are found mostly in male patients. Nowadays, due to wider use of non-invasive imaging, AVFs are discovered with increasing frequency in patients with minimal or no symptoms. Traditionally, these fistulas were considered "surgical." However, in the modern endovascular era, selected patients can be effectively and safely treated with embolization although surgical ligation continues to have an important role in their management.

Analysis of the Relationship between the Location of the Anterior Ethmoid Artery and Keros Classification.

Objective We sought to identify a relationship between skull base height and anterior ethmoid artery (AEA) anatomy. Study Design Retrospective radiologic chart review. Setting University of Arkansas for Medical Sciences. Subjects Patients seen in a tertiary rhinology clinic between September 2014 and October 2015. Methods Review of 101 maxillofacial computed tomography scans with institutional review board approval. Skull base height and AEA locations were measured on each side. Prevalence of the AEA outside of the skull base and distance of the AEA from skull base were calculated and compared with Keros classification using χ2 testing. Comparisons of skull base height between sexes and age and distance between skull base and the AEA among Keros 2 and Keros 3 patients were made using an unpaired, 2-tailed t test. Results The AEA was located below the skull base in 25.7% of cases and more often in Keros type 3 (55%) than in Keros type 2 (29.5%) or Keros type 1 (0%) ( P < .05). Male patients were significantly more likely to have a greater average skull base height (5.25 vs 4.28 mm) and to have AEAs below the skull base (38.4% vs 14.8%). In addition, the distance of the AEA from the skull base was significantly higher in Keros type 3 patients compared with Keros type 2 patients (4.55 vs 3.42 mm, P = .001). Conclusions Variations in the AEA pathway occur more in male patients and those with higher Keros classifications. The distance between the variant AEA and the skull base increases with higher Keros classification. Keros classification can yield insight to the location of the AEA.

Computer-assisted analysis of anatomical relationships of the ethmoidal foramina and optic canal along the medial orbital wall.

Typically, the medial orbital wall contains an anterior ethmoidal foramen (EF) and a posterior EF, but may also have multiple EFs transmitting the arteries and nerves between the orbit and the anterior cranial fossa. The aim of this study is to determine a patient-friendly landmark of the medial orbital wall and to specify a precise location of the ethmoidal foramens (EF) in order to standardize certain anatomical marks as safe ethmoidal arteries. Orientation points on the anterior ethmoidal foramen (AEF), posterior ethmoidal foramen (PEF) and middle ethmoidal foramen (MEF) were investigated in 262 orbits. Using a software program, distances between each foramen and the midpoint of the anterior lacrimal crest (ALC), the optic canal (OC), and some important angles were measured. The EFs were identified as single in 0.8%, double in 73.7%, triple 24,4% and quadruple in 1.1% specimens. The mean distances between ALC and AEF, ALC and PEF and ALC and MEF were 27.7, 10.6, and 12.95 mm, respectively. The distances from ALC-AEF, AEF-PEF, and PEF-OC were 27.7 ± 2.8, 10.6 ± 3.3, 5.4 ± 1 mm. The angles from the plane of the EF to the medial border of the OC were calculated as 13.2° and 153°, respectively. The angle from the AEF to the medial border of the OC was based on the plane between the ALC and AEF was 132°. The occurrence of multiple EF with an incidence of 25% narrows the borders of the safe region in the medial orbital wall. Safe distance of the ALC-EF was measured as 22.1 mm on medial wall. The line of the location of the EF was calculated 16.2 mm. In this study, it was possible to investigate the variability of the orbital orifice of the EF and the feasibility of the EA, to observe various angles of the orbital wall bones and to calculate the lengths of some parameters with the help of certain software.

Transfemoral venous approach for Onyx embolization of anterior fossa dural arteriovenous fistulae.

BACKGROUND: Dural arteriovenous fistulae (dAVF) of the anterior fossa have a malignant course since they exclusively drain into cortical frontal veins and warrant aggressive treatment. Classically, these lesions have been treated with microsurgical clipping of the fistulous connection. We describe a transvenous approach for Onyx embolization of these lesions that relies on distal venous access using a flexible new-generation guide catheter. METHODS: A retrospective review was performed of all patients with an anterior fossa dAVF treated at the Medical University of South Carolina since 2010. Charts, procedural records, angiographic images and follow-up were reviewed. Three patients were identified. RESULTS: Transfemoral venous access and distal transvenous sinus access was obtained in a retrograde fashion to at least the level of the right transverse sinus. Once a distal guide catheter position was obtained within the venous sinus system, a microcatheter was advanced into the predominant draining anterior frontal cortical vein in preparation for embolization. Onyx 34 embolization was then initiated from this position with the objective of achieving penetration across the vascular shunt. CONCLUSIONS: Our experience demonstrates that transvenous Onyx embolization offers an effective and safe alternative to the classic neurosurgical treatment of anterior fossa dAVF.

Transcervical double mandibular osteotomy approach to the infratemporal fossa.

BACKGROUND: In this study, we propose an alternative to the traditional transmandibular lower lip and chin splitting approach for exposing high infratemporal fossa and parapharyngeal space lesions involving the carotid canal and jugular foramen. METHODS: We present 2 cases of high skull base tumors removed transcervically with anterior and posterior segmental mandibulotomies preserving the mental nerve without the use of a lip or chin incision. RESULTS: Making the posterior osteotomy in an inverted L configuration is necessary so that the coronoid process does not prevent rotation of the mandible out of the visual field. Both patients had complete tumor resection with access to the carotid canal and jugular foramen and functional preservation of the mental nerve and marginal branch of the facial nerve. Neither patient had malocclusion or other dental complications from the approach. CONCLUSIONS: This novel technique is useful for providing excellent access to high infratemporal fossa or parapharyngeal space tumors. It avoids the traditional chin or lip incision and preserves the mental and facial nerves and is a useful procedure in the armamentarium of skull base/cerebrovascular neurosurgeons.

Endovascular management of anterior cranial fossa dural arteriovenous malformations. A technical report and anatomical discussion.

Dural arteriovenous fistulas (dAVFs) of the anterior cranial fossa have traditionally been treated by open surgical disconnection. Safe navigation through the ophthalmic artery or fragile cortical veins has historically provided a barrier to effective endovascular occlusion of these lesions. Using current microcatheter technology and embolic materials, safe positioning within the distal ophthalmic artery, beyond the origin of the central retinal artery, is achievable. We describe two cases in which anterior cranial fossa dAVFs were treated by exclusively endovascular strategies, and highlight the pertinent technical and anatomic considerations. We discuss the clinical symptoms resulting from the differing venous drainage patterns.

Ruptured anterior communicating artery aneurysm associated with anterior cranial fossa dural arteriovenous fistula--case report.

A 77-year-old man presented with an extremely rare association of anterior cranial fossa dural arteriovenous fistula (AVF) with anterior communicating artery (ACoA) aneurysm manifesting as consciousness deterioration due to intracerebral hemorrhage in the left frontal lobe and diffuse subarachnoid hemorrhage. Angiography confirmed the association of a dural AVF fed by both ethmoidal arteries and an ACoA aneurysm. Surgery for these two lesions was performed concurrently, and the ACoA aneurysm was found to be responsible for the hemorrhage. This association seems incidental, but is clinically significant since the preoperative determination of the bleeding point is difficult. We conclude that these two lesions should be treated simultaneously, to avoid leaving the ruptured point untreated.

Dural arteriovenous fistula of the anterior cranial fossa with carotid artery stenosis treated by simultaneous transarterial embolization and carotid artery stenting.

A 71-year-old male presented with a rare case of dural arteriovenous fistula (AVF) of the anterior cranial fossa associated with carotid artery stenosis manifesting as a transient visual disorder. The therapeutic strategy was complicated because the collateral network to the ischemic brain from the external carotid artery was associated with the dural AVF. Transarterial embolization of the shunt was performed simultaneously with carotid artery stent placement. The patient showed good recovery despite a tiny skin ulcer around his nose.

Anterior cranial fossa dural arteriovenous fistula with bilateral cortical drainers--case report.

A 58-year-old man presented with sudden onset of severe headache. Computed tomography demonstrated subarachnoid hemorrhage and right acute subdural hematoma. He had no neurological deficits. Cerebral angiography showed an anterior cranial fossa dural arteriovenous fistula (AVF) supplied by the bilateral ethmoidal arteries. A fistula was suggested on the right side, and the dural AVF drained into the superior sagittal sinus via the bilateral frontal cortical veins. Venous varix was observed at both drainage sites. Bifrontal craniotomy with right-side dural incision was performed and the fistula was interrupted. Postoperative angiography demonstrated a persistent fistula draining into the left cortical vein. Nineteen days later, bifrontal craniotomy with left-side dural incision was performed and the draining vein was completely coagulated with the aid of intraoperative angiography. Postoperatively, there was no detectable residual fistula. He was discharged without neurological deficits 2 weeks after surgery. The present case of anterior cranial fossa dural AVF with bilateral cortical drainers shows that drainer occlusion at two points may be needed for complete obliteration of the drainers because the fistulous connection may not be simple.

Arteriovenous fistula arising from the persistent primitive olfactory artery with dual supply from the bilateral anterior ethmoidal arteries.

A 59-year-old male presented with generalized seizure. The patient had not been aware of any traumatic head injuries or preceding infection, and had no contributory medical history. On admission, he was alert and well oriented, without neurological impairment or headache. He was afebrile and blood examination showed no abnormal findings. Computed tomography revealed an irregular intracerebral hematoma, 3 x 1.5 cm in diameter, in the left rectal gyrus. Cerebral angiography showed an arteriovenous fistula (AVF) in the anterior cranial fossa supplied only by the persistent primitive olfactory artery (PPOA) originating from the anterior cerebral artery, forming a shunt to an ascending cortical vein, and drained by the superior sagittal sinus. The patient underwent endovascular obliteration of the AVF via the transarterial route. Immediately after successful isolation, angiography showed that the bilateral anterior ethmoidal arteries supplied the AVF. The feeding branches from the left anterior ethmoidal artery were completely occluded via the ophthalmic artery, but introduction of the catheter into the right ophthalmic artery markedly decreased the stump pressure. Follow-up angiography performed at 3 and 8 weeks following embolization showed spontaneous resolution of the residual AVF without findings of recanalization or new abnormal channels. AVF arising in the anterior cranial fossa may be associated with an unusual pattern of the blood supply when including the PPOA.

Dural arteriovenous fistula in the anterior cranial fossa: four case reports.

Three of 4 cases of dural arteriovenous fistulas (DAVFs) in the anterior cranial fossa were detected incidentally by magnetic resonance (MR) imaging, and one case manifested as intracerebral hemorrhage. Cerebral angiography revealed fistulas located in the anterior cranial fossa. Three patients underwent surgery, and the fistulas were successfully obliterated. One patient with nonruptured DAVF requested conservative medical management. Incidental detection of asymptomatic or nonruptured DAVFs in the anterior cranial fossa has increased with the wider use of MR imaging. Increase in the size of a venous varix is the indicator for aggressive therapeutic intervention in a patient receiving conservative medical management for asymptomatic or nonruptured DAVFs in the anterior cranial fossa.

Intraorbital arteriovenous malformation: issues in surgical management.

Intraorbital arteriovenous malformations are infrequent but, when present, typically require complex surgical management. Computed tomography and magnetic resonance imaging help characterize lesion structure, location, and relationship to intraorbital anatomy. Frequently complex, intervention should be prompted by significant proptosis, increased intraocular pressure, pain, bleeding, ulceration, or high-output cardiac complications. For more controlled surgical debridement, angiographic embolization may help occlude the nidus and feeding vessels temporarily. Utmost caution must be taken to avoid injury to the optic nerve and ophthalmic artery. We present a rare case of complex, intraorbital arteriovenous malformation, as well as discuss aspects of management and relevant literature.

Venous aneurysm development associated with a dural arteriovenous fistula of the anterior cranial fossa with devastating hemorrhage--case report.

A 67-year-old man presented with devastating intracranial hemorrhage (ICH) from an anterior cranial fossa dural arteriovenous fistula (DAVF). Four years earlier, digital subtraction angiography had disclosed a DAVF at the right anterior cranial fossa fed mainly by the ethmoidal branches of the bilateral sphenopalatine arteries and slightly by the ethmoidal arteries of the bilateral ophthalmic arteries, and drained primarily by the sphenoparietal and cavernous sinuses via two dilated cortical veins and slightly by the superior sagittal sinus via a frontal ascending vein. Three-dimensional computed tomography angiography revealed the development of a venous aneurysm on the main draining vein over a 4-year period, but no other changes. Venous aneurysm development may be part of the natural history of DAVF with cortical venous drainage and may contribute to the occurrence of ICH.

Anterior ethmoidal artery aneurysm and intracerebral hemorrhage.

The association between the formation of intracranial aneurysms and situations of increased blood flow in certain areas of the brain is well accepted today. It has been seen in association with arteriovenous malformations of the brain, carotid occlusion, and Moyamoya disease. The occurrence of aneurysms in small arteries of the skull base, with the exception of the intracavernous carotid artery, however, is rare. We report a case of a 55-year-old woman who presented with an intracerebral hemorrhage caused by a ruptured anterior ethmoidal artery aneurysm. To the best of our knowledge, this is only the second case of documented intracranial bleeding from such a lesion.

The anatomic landmarks of ethmoidal arteries for the surgical approaches.

Knowledge of variations in the possible patterns of origins, courses, and distributions of the ethmoidal arteries are necessary for the diagnosis and important for the treatment of orbital disorders. Ethmoidal arteries are damaged in endonasal surgical interventions and in operations performed on the inner wall of the orbita.A description of the anatomic landmarks of the ethmoidal arteries and ethmoidal canals is presented, based on data from microdissection in 19 adult cadavers studied after injection of red-dyed latex into the arterial bed. In all subjects, each of ethmoidal arteries originated from ophthalmic artery. The anterior ethmoidal artery was observed in all specimens except for one case. The diameter of the artery thicker than the posterior ethmoidal artery was 0.92 +/- 0.2 mm on the right and 0.88 +/- 0.15 mm on the left. The branching of the anterior ethmoidal artery from the ophthalmic artery was determined in four different types. The diameter of the posterior ethmoidal artery was measured as 0.66 +/- 0.21 mm on the right and 0.63 +/- 0.19 mm on the left. The anterior ethmoidal canal was located between the second and third lamella in 29 of 38 cases. The mean distance between the limen nasi and anterior ethmoidal canal was 48.1 +/- 3.2 mm.The article confirms the well-known variability of the ethmoidal arteries and their topographic relation to the ethmoidal canals. Advances in surgical techniques, instrumentation, and regional arterial anatomy have resulted in functional operations of endoscopic sinus and orbital surgery with fewer complications.

Bilateral ethmoidal dural arteriovenous fistulae: a previously unreported entity: case report.

OBJECTIVE AND IMPORTANCE: Ethmoidal dural arteriovenous fistulas (AVFs) are rare intracranial lesions associated with a high risk of intracranial hemorrhage. Reported hemorrhage rates have ranged from 62 to 91%, and an aggressive clinical course is more likely than a benign clinical course. We describe the first case of a patient with bilateral ethmoidal dural AVFs. CLINICAL PRESENTATION: A 50-year-old man presented with posterior fossa subarachnoid hemorrhage and cerebellar intraparenchymal hemorrhage. Angiography revealed a tentorial AVF and a complex anterior ethmoidal dural AVF. INTERVENTION: The tentorial AVF was treated with preoperative embolization and surgical obliteration. On follow-up angiography, the ethmoidal dural AVF was not considered amenable to embolization. A right modified orbitozygomatic approach was performed and the right-sided fistula was interrupted. Intraoperative angiography revealed obliteration of the right-sided fistula, but a persistent fistula on the left. Further surgical exploration revealed this contralateral anterior ethmoidal dural AVF, which was clip ligated. No residual fistula was noted on intraoperative angiography. CONCLUSION: Anterior ethmoidal dural AVFs may occur bilaterally. Given their complex angiographic appearance, their presence bilaterally may not be readily apparent on preoperative angiography. Intraoperative angiography is crucial to identify a contralateral fistula and to verify that ligation has been curative.