Abstract: Objective: Meningiomas presented preferred intracranial distribution, which may reflect potential biological natures. This study aimed to analyze the preferred locations of meningioma according to different biological characteristics. Method: A total of 1,107 patients pathologically diagnosed with meningiomas between January 2012 and December 2016 were retrospectively analyzed. Preoperative MRI were normalized, and lesions were semiautomatically segmented. The stereospecific frequency and p value heatmaps were constructed to compare two biological phenotypes using two-tailed Fisher's exact test. Age, sex, WHO grades, extent of resection (EOR), recurrence, and immunohistochemical markers including p53, Ki67, epithelial membrane antigen (EMA), progesterone receptor (PR), and CD34 were statistically analyzed. Recurrence-free survival (RFS) were analyzed by Kaplan-Meier method. Result: Of 1,107 cases, convexity (20.8%), parasagittal (16.1%), and falx (11.4%) were the most predominant loci of meningiomas. The p-value heatmap suggested lesion predominance in the left frontal and occipital convexity among older patients while in the left sphenoid wing, and right falx, parasellar/cavernous sinus, and middle fossa among younger patients. Lesions located at anterior fossa and frontal structures were more frequently seen in the male while left parietal falx and tentorial regions, and right cerebellopontine angle in the female. Grades II and III lesions presented predominance in the frontal structures compared with grade I ones. Meningiomas at the left parasagittal sinus and falx, tentorium, intraventricular regions, and skull-base structures were significantly to receive subtotal resection. Lesions with p53 positivity were statistically located at the left frontal regions and parasellar/cavernous sinus, higher Ki67 index at the left frontal and bilateral parietal convexity and right parasellar/cavernous sinus, EMA negativity at the right olfactory groove and left middle fossa, and CD34 positivity at the sellar regions and right sphenoid wing. Tumor recurrence rates for grades I, II, and III were 2.8, 7.9, and 53.8%, respectively. Inferior RFS, higher Ki67 index, grades II and III, and a larger preoperative volume were observed in older patients. Recurrent meningiomas were more frequently found at the occipital convexity, tentorium, sellar regions, parasagittal sinus, and left sphenoid wing. Conclusion: The preferred locations of meningioma could be observed according to different biological characteristics, which might be helpful for clinical decisions.

Abstract: Meningiomas comprise the most frequent intracranial benign tumors accounting for approximately one third of all intracranial neoplasms, and generally follow an indolent disease course with a typically benign nature and slow-growing behaviour. Although majority of meningiomas may follow an indolent disease course, affected patients may suffer from a plethora of symptoms with regard to lesion location. Symptoms typically occur as a result of the mass effect leading to compression of critical neurovascular structures. Headache, focal seizures, weakness in the limbs, visual disturbances, loss of smell, impaired memory or hearing functions may be observed. Advances in neurosurgery may allow for an improved toxicity profile following surgical resection as the traditional and a leading mode of management for meningiomas located at accessible brain areas. Nevertheless, vigilance is required given the morbidity and mortality risks associated with meningioma surgery particularly for elderly patients. In this context, radiation therapy (RT) may offer a viable alternative or adjunctive modality of management for meningiomas. Management of cavernous sinus meningiomas in intricate association with critical neurovascular structures pose a formidable challenge to the treating physicians. Attempting at extensive surgical procedures may be associated with substantial morbidity and even mortality. In this context, selected patients may benefit from a tailored multimodality approach including less extensive surgical resection followed by subsequent irradiation. Primary advantages of this refined therapeutic strategy may include improved toxicity profile along with improved functionality and quality of life. Herein, we assess multimodality management of cavernous sinus meningiomas with less extensive surgery followed by subsequent irradiation.

Abstract: Objective Cavernous internal carotid artery (ICA) aneurysms are frequently diagnosed incidentally and the benign natural history of these lesions is well known, but there is limited information assessing the risk of growth in untreated patients. The authors sought to assess and analyze risk factors in patients with cavernous ICA aneurysms and compare them to those of patients with intracranial berry aneurysms in other locations. Methods Data from consecutive patients who were diagnosed with a cavernous ICA aneurysm were retrospectively reviewed. The authors evaluated patients for the incidence of cavernous ICA aneurysm growth and rupture. In addition, the authors analyzed risk factors for cavernous ICA aneurysm growth and compared them to risk factors in a population of patients diagnosed with intracranial berry aneurysms in locations other than the cavernous ICA during the same period. Results In 194 patients with 208 cavernous ICA aneurysms, the authors found a high risk of aneurysm growth (19.2% per patient-year) in patients with large/giant aneurysms. Size was significantly associated with higher risk of growth. Compared to patients with intracranial berry aneurysms in other locations, patients with cavernous ICA aneurysms were significantly more likely to be female and have a lower incidence of hypertension. Conclusions Aneurysms of the cavernous ICA are benign lesions with a negligible risk of rupture but a definite risk of growth. Aneurysm size was found to be associated with aneurysm growth, which can be associated with new onset of symptoms. Serial follow-up imaging of a cavernous ICA aneurysm might be indicated to monitor for asymptomatic growth, especially in patients with larger lesions.

Abstract: The parasellar region, located around the sella turcica, is an anatomically complex area representing a crossroads for important adjacent structures. Several lesions, including tumoral, inflammatory vascular, and infectious diseases may affect this area. Although invasive pituitary tumors are the most common neoplasms encountered within the parasellar region, other tumoral (and cystic) lesions can also be detected. Craniopharyngiomas, meningiomas, as well as Rathke's cleft cysts, chordomas, and ectopic pituitary tumors can primarily originate from the parasellar region. Except for hormone-producing ectopic pituitary tumors, signs and symptoms of these lesions are usually nonspecific, due to a mass effect on the surrounding anatomical structures (i.e., headache, visual defects), while a clinically relevant impairment of endocrine function (mainly anterior hypopituitarism and/or diabetes insipidus) can be present if the pituitary gland is displaced or compressed. Differential diagnosis of parasellar lesions mainly relies on magnetic resonance imaging, which should be interpreted by neuroradiologists skilled in base skull imaging. Neurosurgery is the main treatment, alone or in combination with radiotherapy. Of note, recent studies have identified gene mutations or signaling pathway modulators that represent potential candidates for the development of targeted therapies, particularly for craniopharyngiomas and meningiomas. In summary, parasellar lesions still represent a diagnostic and therapeutic challenge. A deeper knowledge of this complex anatomical site, the improvement of imaging tools, as well as novel insights into the pathophysiology of presenting lesions are strongly needed to improve the management of parasellar lesions.

Abstract: To evaluate the clinical features, management, and outcomes of orbital schwannomas. Retrospective study analyzing 20 orbital schwannomas in 18 patients managed in an orbital service over 26 years. Clinical, radiological, histological, and surgical procedural data were analyzed. Mean age of the study population was 40.89 ± 20.84 years. The most common nerve of origin was frontal nerve (50%), and majority of patients (70%) had a superior and/or posteriorly located tumor. Five patients (27.8%) had optic neuropathy at presentation, and 3 of them showed improved vision after intervention. Surgical resection was performed for all except for 1 patient who underwent fractionated stereotactic radiotherapy. Six subjects had extension of tumor into the cavernous sinus, and 3 of them underwent combined neurosurgical intervention with stereotactic neuronavigation. Outcomes were largely favorable with majority achieving complete excision. Two out of 6 incomplete resections experienced regrowth requiring second surgical intervention. Surgical complications include decreased vision, diplopia, ptosis, and mydriasis. Orbital schwannomas are uncommon slow-growing tumors which can result in visual loss. Prognosis can be favorable even in presence of pre-operative optic neuropathy if there is early intervention. Schwannomas confined to the orbit can usually be completely excised with good outcomes. Schwannomas extending intra-cranially may undergo incomplete excision to preserve vital structures, leaving residual disease, but generally have satisfactory results. Stereotactic neuronavigation and frozen section are useful intra-operative tool to aid management and minimize complications. Fractionated radiotherapy can be considered as an alternative or adjunctive treatment for patients not amenable for surgical resections.

Abstract: Ectopic pituitary adenomas (EPAs) are extremely rare pituitary adenomas located outside the sella turcica without any connection with intrasellar components. This study aims to review all the reported cases to date and describe the clinical characteristics of EPAs. In a retrospective chart review, 14 patients were identified with EPAs in our hospital. A literature review was performed, and 166 cases in the literature met the criteria. Clinical data were analyzed. Of 180 patients with EPAs, the mean age at diagnosis was 45.4 years, and 66.5% of the patients were females. EPAs were mainly located in the sphenoid sinus (34.4%) and suprasellar region (25.6%), followed by the clivus (15.6%), cavernous sinus (13.3%) and nasopharynx (5.6%). Adrenocorticotropic hormone (ACTH)-secreting (38.9%) and nonfunctioning (27.2%) adenomas were predominant. Patients with suprasellar EPAs were more likely to present menstrual disorders and visual changes, while patients with clival EPAs were more likely to suffer from headaches. EPAs in the cavernous sinus and suprasellar space were more likely to be initially misdiagnosed as a suspicious intrasellar mass on imaging examination. The complete tumor resection rates for EPAs in the sphenoid sinus, suprasellar region, clivus, cavernous sinus and nasopharynx were 72.3%, 88.6%, 45.0%, 73.3% and 88.9%, respectively. EPA clinical characteristics varied across different tumor locations and hormone-secreting types. In addition to comprehensive hormone evaluation and careful review of imaging data, nuclear medicine and surgical biopsy should also be considered when facing differential difficulty. EPA management should be individualized.

Abstract: The clinical course of pituitary adenoma can be highly variable. Aggressive pituitary tumours may require multimodal therapy with multiple operations. Even standard pituitary adenomas exhibit relatively high long-term recurrence rates and delayed intervention is often required. The indications for revision surgery in the endoscopic era are expanding for both functioning and nonfunctioning tumours, including access to the cavernous sinus and intracranial compartments. Although revision surgery can be challenging, it has been demonstrated to be both safe and effective. The question of the use of early radiotherapy in pituitary adenoma remains controversial. Our increasing understanding of pituitary tumour biology facilitates individualized treatment and surveillance protocols, with early intervention in high-risk adenoma subtypes. In this review, we discuss the treatment options for recurring pituitary tumours and focus on the role of revision surgery.

Abstract: Although the sphenoidal emissary foramen (SEF) and its content are anatomically and clinically relevant, accurate description of them in the modern literature is lacking. This study aimed to examine and describe the SEF and its content (the sphenoidal emissary vein [SEV]). We analyzed 1,000 computed tomography (CT) images, 170 dry skulls, 50 formalin-fixed specimens, and three specimens (heads) following guidelines proposed by Dr. Albert L. Rhoton Jr. MD for latex injection. SEV morphology was determined by histological staining and electron microscopy. The SEF was observed in 46.8% of the CTs studied (25.4% bilateral and 21.4% unilateral), and 45.2% of the dry skulls (18.8% bilateral and 26.4% unilateral). In 9.5% of CTs and 21.1% of dry skulls there was a blind channel in the external surface of the cranial base; since there was no communication with the cranial cavity, it was not considered as the SEF. During the dissections, the SEF was found in seven individuals. In three of them, the SEV was an alternative route for venous drainage of the venous plexus of the foramen ovale. Its walls were composed of collagen fibers and its endothelium contained rhomboid cells resembling those commonly found in the superior sagittal sinus. The presence of the SEF and SEV can anatomically explain the spread of certain cranial base pathologies from or toward Meckel's cave or the cavernous sinus, and should be taken into account during procedures in the middle cranial fossa, percutaneous approaches, odontological procedures, and treatment of dural arteriovenous fistulas. Clin. Anat., 33:767-781, 2020. © 2019 Wiley Periodicals, Inc.

Abstract: Meningioma arising in the inner third of the sphenoidal wing has been well recognized since the origin of neurosurgery, yet it still poses a formidable challenge for the surgeon Treatment strategies can be optimized through a tailored approach to surgical timing and use of a non-surgical armamentarium The aim of this study was to evaluate the long-term effect of different strategies on progression-free survival and overall survival We examined the clinical records of brain tumor patients to assess determinants for surgery (extent of tumor removal, postoperative complications) and for progression-free survival and overall survival in relation to timing of surgery eventually followed by stereotactic radiosurgery (SRS) The records of 60 patients were retrospectively reviewed, from preoperative assessment to a median follow-up of 104 months All were symptomatic with prevalently visual symptoms (422%), large tumors (median diameter 344 cm), extension into the cavernous sinus (383%), and severe vascular involvement of one or more encased or narrowed vessels (50%) Subtotal removal was achieved in 40% of cases, mainly determined by cavernous sinus and vascular involvement; neurological complications occurred in 183% (persistent in 67% due to oculomotor and vascular injury) The overall rate of symptom improvement was 323% at 3 months and 495% at 12 months Radiological monitoring prevented clinical progression; tumor progression occurred in 117% of cases There were significant differences in progression-free survival between patients with (median 46 months) and those without (median 104 months) recurrence (p = 0002): 125% after total removal, 62% after subtotal removal and adjuvant SRS, and 285% after subtotal removal and observation The related Kaplan-Meier survival curve showed no significant difference between the three strategies Further, disease progression after recurrence was noted in 286% of cases, but overall survival was not influenced by either tumor recurrence or type of treatment Treatment failure was recorded in four cases (67%): one perioperative death and three later on Surgery is the mainstay for the treatment of symptomatic meningioma and to restore neurological function; however, resectability is limited by vascular and cavernous sinus involvement Careful postoperative monitoring prevented clinical progression and adjuvant or adjunctive SRS proved effective in tumor control A low surgical complication rate and excellent long-term outcomes were achieved with this strategy

Abstract: Aggresssive pituitary tumors are defined as radiologically invasive, exhibiting a rapid growth and a poor response to the medical and surgical treatment options. The role of magnetic resonance imaging (MRI) is fundamental to assess tumor aggressiveness before surgical exploration. Distinction between cavernous sinus invasion and cavernous sinus compression is often challenging and cannot be solved always by using the Knosp criteria. Ideally, T2W images demonstrating the ruptured internal dural wall of cavernous sinus is the ultimate proof of cavernous sinus invasion. Subtle tumor volume increase in a short time can be shown when sequential MR images are rigorously replicable. A microcystic pattern observed on T2W images frequently reflects a potentially aggressive tumor as observed in silent corticotroph pituitary adenomas.

Abstract: Compression of the internal carotid artery (ICA) in the cavernous sinus area is a rare event and is mostly associated with pituitary adenomas and meningiomas. Other causes of ICA compression are less well known. We present a rare case of granulomatous hypophysitis causing compression of the ICA, which was treated successfully with immune-suppressive agents. The electronic database MEDLINE (PubMed) was searched systematically and other cases with ICA compression were identified and analyzed. A female patient with a history of two previous transsphenoidal operations for suspected pituitary adenoma and post-operative complete pituitary insufficiency presented with severe headaches, nausea, fatigue, and diplopia. Pituitary MRI scan suggested relapse of the pituitary lesion with atypical bilateral infiltration of cavernous sinuses and compression of ICAs. After histological reevaluation of her previous pituitary operations, granulomatous hypophysitis was diagnosed. Treatment was started with high doses of prednisolone. With decreasing doses of prednisolone, symptoms recurred, and azathioprine was started, followed by administration of rituximab resulting in clinical recovery and regression of ICA compression. Literature analysis disclosed 36 case reports with ICA compression in the cavernous sinus region (12 pituitary adenoma, 6 meningioma, 7 hypophysitis, 5 other tumors, and 4 other etiologies). Two cases of hypophysitis recovered completely; five cases improved only partly. In the case of ICA compression, clinical signs, onset of symptoms, radiological findings and pituitary insufficiencies should be thoroughly evaluated, and hypophysitis should be considered as a possible cause. In our patient, treatment with azathioprine and, finally, rituximab was successful.

Abstract: Large to giant sphenoid wing meningiomas (SWMs) remain surgically challenging due to frequent vascular encasement and a tendency for tumoral invasion of the cavernous sinus and optic canal. We aimed to study the quality of resection, postoperative clinical evolution, and recurrence rate of large SWMs. This retrospective study enrolled 21 patients who underwent surgery between January 2014 and December 2019 for SWMs > 5 cm in diameter (average 6.3 cm). Tumor association with cerebral edema, extension into the cavernous sinus or optic canal, degree of encasement of the major intracranial arteries, and tumor resection grade were recorded. Cognitive decline was the most common symptom (65% of patients), followed by visual decline (52%). Infiltration of the cavernous sinus and optical canal were identified in five and six patients, respectively. Varying degrees of arterial encasement were seen. Gross total resection was achieved in 67% of patients. Long-term follow-up revealed improvement in 17 patients (81%), deterioration in two patients (9.5%), and one death (4.7%) directly related to the surgical procedure. Seven patients displayed postoperative tumor progression and two required reintervention 3 years post initial surgery. Tumor size, vascular encasement, and skull base invasion mean that, despite technological advancements, surgical results are dependent on surgical strategy and skill. Appropriate microsurgical techniques can adequately solve arterial encasement but tumor progression remains an issue.

Abstract: OBJECTIVE Gamma Knife surgery (GKS) obliterates 65%-87% of cavernous sinus dural arteriovenous fistulas (CSDAVFs). However, the hemodynamic effect on GKS outcomes is relatively unknown. The authors thus used the classification scheme developed by Suh et al. to explore this effect. METHODS The authors retrospectively (1993-2016) included 123 patients with CSDAVFs who received GKS alone at the institute and classified them as proliferative type (PT; n = 23), restrictive type (RT; n = 61), or late restrictive type (LRT; n = 39) after analyzing their pre-GKS angiography images. Treatment parameters, the presence of numerous arterial feeders, and venous drainage numbers were compared across the CSDAVF types. Patients' follow-up MR images were evaluated for the presence of complete obliteration. A Kaplan-Meier analysis was conducted to determine the correlation between CSDAVF types and outcomes. RESULTS The 36-month probability of complete obliteration was 74.3% for all patients, with no significant differences across types (p = 0.56). PT had the largest radiation volume (6.5 cm3, p < 0.001), the most isocenters (5, p = 0.015) and venous drainage routes (3, p < 0.001), and the lowest peripheral dose (16.6 Gy, p = 0.011) and isodose level coverage (64.3%, p = 0.006). CSDAVFs presenting with ocular patterns were less likely to be completely obliterated (hazard ratio 0.531, p = 0.009). After adjustment for age, CSDAVFs with more venous drainage routes were less likely to be completely obliterated (hazard ratio 0.784, p = 0.039). CONCLUSIONS GKS is an equally effective treatment option for all 3 CSDAVF types. Furthermore, the number of venous drainage routes may help in predicting treatment outcomes and making therapeutic decisions.

Abstract: Thyrotropin-secreting pituitary adenoma is a rare disorder and was recently classified as an aggressive tumor in the World Health Organization guidelines. The number of available studies on cosecreting thyrotropin/growth hormone pituitary adenoma is especially limited. A single-center retrospective analysis of patients with thyrotropin/growth hormone pituitary adenoma was performed at Peking Union Medical College Hospital, one of the largest pituitary care centers in China, from January 2012 to January 2020. Additionally, data about cosecreting thyrotropin/growth hormone pituitary adenoma were collected and analyzed. The diagnosis, therapy and follow-up were all compared to that of solo-secreting thyrotropin pituitary macroadenoma. Twelve patients (10.81%) were identified with thyrotropin/growth hormone pituitary adenoma at Peking Union Medical College Hospital within 8 years, all of which were classified as macroadenoma. Compared with solo-secreting thyrotropin pituitary macroadenoma, thyrotropin/growth hormone pituitary adenoma presented with a higher proportion of cavernous sinus invasion (50%) and had a larger maximum tumor diameter. The patients had a lower surgical complete remission rate and a worse prognosis. Interestingly, they revealed a striking phenomenon of “solo part remission”. Thyrotropin/growth hormone pituitary adenoma is rare. Some patients do not present with the typical manifestations; however, the possibility of a cosecretion tumor should not be excluded. A preoperative comprehensive evaluation of anterior pituitary hormones is necessary. Thyrotropin/growth hormone pituitary adenoma revealed a high tendency of invasion, and the prognosis of patients with thyrotropin/growth hormone pituitary adenoma was poor. If necessary, timely postoperative drug administration or radiotherapy should be carried out.

Abstract: Cavernous sinus meningiomas are rare benign tumors arising from the dural wall of the cavernous sinus. These complex lesions are difficult to access surgically but can lead to cranial nerve palsies if left untreated. The case described in this video involved a 14-yr-old girl who presented initially with right ocular pain at 9 yr old. Strabismus of the right eye developed when she was 10 yr old; it was treated surgically without improvement. She developed ptosis and worsening strabismus at age 13 yr, at which time magnetic resonance imaging revealed a lesion in the anterior cavernous sinus and superior orbital fissure. Given the progressively worsening oculomotor palsy and potential for future tumor growth because of her young age, the patient's family wished to pursue surgical rather than radiation treatment. The patient underwent a right lateral orbitotomy for exploration and resection of the lesion. She tolerated the procedure well. Postoperatively, she experienced improvement in her ocular pain and persistent oculomotor nerve palsy without any new neurologic deficits. Her cosmetic results from this incision were satisfactory. Postoperative computed tomography demonstrated thinning of the right lateral orbital wall and removal of the tumor. The pathological analysis of the tissue was consistent with a grade 1 meningioma. This video demonstrates the opportunity to resect a lesion from the cavernous sinus that prevents progressive cranial neuropathies. Some cavernous meningiomas are well circumscribed and can be resected totally. The patient's parents provided consent for publication.

Abstract: The middle cranial fossa is bounded anteriorly by the sphenoid ridge, medially by the lateral wall of the cavernous sinus and Meckel's cave, posteriorly by the sphenoid wing and petrous bone, and laterally by the greater wing of sphenoid and squamous temporal bone. In normal individuals, unnamed venous channels within the dura and arachnoid granulations can be seen on the floor of this fossa by the operating surgeon. Meningiomas arising mainly from the dura of the floor are uncommon, and middle fossa meningiomas have been arbitrarily named so based on an attachment of more than 75% to this location. They tend to present clinically at a large size and require special considerations for surgical treatment.

Abstract: Introduction: Teeth displacement in the maxillary sinus is one of the most frequently described peri-extraction complications in oral surgery. Roots or whole teeth accidentally displaced during an avulsion process are the most common cause of foreign bodies in the maxillary sinus. It exposes the patient to more or less serious complications that can go as far as development of pneumonia or septic thrombosis of the cavernous sinus in rare cases. Several therapeutic solutions can be proposed to manage this complication, ranging from therapeutic abstention to the removal of the dental component using various techniques. Corpus: The pedagogical objectives of this article are to explain the main characteristics of this complication as well as its treatment. Through a systematic review of the literature according to the PRISMA methodology, the risk factors, prevention, diagnosis, complications, and management of teeth displacement will be discussed. A treatment decision tree will be proposed to guide practitioners in the management of a tooth or dental root displaced into the sinus. Conclusion: This article summarizes the importance of pre-extraction radiographic examinations for preventive purposes and their analysis to guide the practitioner in the choice of an appropriate surgical technique. Furthermore, the surgical management in almost all cases must be carried out early to prevent later infectious complications.

Abstract: Introduction: Isolated sphenoid sinus inflammatory diseases (ISSIDs) are responsible for about 75% of isolated sphenoid sinus opacifications. Computer tomography (CT) and magnetic resonance imaging (MRI) should be used in a complementary manner for the assessment of ISSIDs. This evaluation sheds some light on the extent of disease and intracranial and intra-orbital involvement. Materials and Methods: The current study aimed to evaluate the medication histories of 14 patients who underwent endoscopic sinus surgery (ESS) for ISSIDs within 2015-2018. This assessment was carried out to analyze the presenting symptoms, diagnostic work-up, additional therapies, and complications. Moreover, it can help us compare our data with pertinent literature. Results: As evidenced by the obtained results, ISSID lesions included bacterial sphenoiditis (42.9%), fungus ball (21.4%), invasive fungal sphenoiditis (14.3%), mucocele (14.3%), and retention cysts (7.1%). In addition, headache was found to be the major complaint, followed by nasal symptoms. Diplopia, and signs and symptoms of the involvement of other cranial nerves were less frequent. All patients underwent endoscopic transnasal sphenoidectomy. The overall survival rate was reported as 92.9% (13/14), and all patients with cranial nerve palsies demonstrated complete clinical remission. Conclusion: Both the review of related literature and our clinical cases were indicative of the dangerous consequences of ISSIDs. Their varied and unspecific presentation and the limited reliability of nasal endoscopy required the cooperation of ENT (ear, nose, and throat) team with other specialists to make an accurate diagnosis and decide on the most appropriate therapeutic choices. If the signs of intracranial complications were detected, surgery should be promptly performed to maximize the chances of recovery.

Abstract: Background and importance Carotid-cavernous fistulas (CCF) are pathological connections between carotid artery branches and the cavernous sinus. They can lead to a variety of symptoms, such as chemosis and double vision, or more insidious events, such as vision loss and intracranial hemorrhage. Although these patients are often treated by endovascular means, we describe a case in which the patient's CCF was not able to be accessed by usual methods and required an open surgical approach. Clinical presentation The patient had progressive chemosis, double vision, and periorbital pain. Angiogram showed an indirect type D CCF with cortical venous drainage with a large sylvian vein that was directly draining the fistula. The patient did not have a dilated superior ophthalmic vein, and the petrosal sinuses could not be catheterized. Therefore, because of the patient's increased risk for intracranial hemorrhage, she was taken to the operating room for an image guided burr hole for direct catheterization of the sylvian vein. From this point, the fistulous point could be catheterized, and the CCF was embolized using onyx. Follow-up angiogram showed complete occlusion. Conclusion This is the first report in literature of an indirect CCF being treated through a transsylvian approach with onyx. This combined open-surgical-and-endovascular approach was necessary to get full resolution of the lesion, and patient had rapid improvement of symptoms.

Abstract: A carotid-cavernous fistula (CCF) is an abnormal connection between the arteries and veins of the cavernous sinus. Iatrogenic CCFs have been described as potential complications following aneurysm coiling, balloon angioplasty, and transsphenoidal surgery. In this case report, we describe a rare case of an iatrogenic direct CCF following mechanical thrombectomy (MT) for acute ischemic stroke. A 78-year-old female presented to an outside hospital with a new onset of right-sided weakness and aphasia and underwent emergency MT for a left middle cerebral artery (MCA) occlusion. The procedure was complicated by iatrogenic injury to the left cavernous internal carotid artery (ICA), which resulted in a direct high-flow CCF. The patient was transferred to our hospital and the fistula was closed with transarterial coils. Ten days later, she returned with diplopia and cranial nerve VI palsy due to residual pseudoaneurysm and was treated with a flow-diverting stent. On follow-up, the patient was neurologically intact and imaging showed no residual fistula. As the frequency of MTs performed for acute ischemic stroke continues to rise, neurointerventionalists should be aware of this potential rare complication and be prepared to manage patients who develop symptomatic CCF.

Abstract: Background: In rare circumstances, patients with intracranial (dural arteriovenous fistulas) DAVFs could be complicated with brainstem engorgement, which might lead to delayed or false diagnosis and subsequent improper management. Methods: On July 2th, 2019, a systematic search was conducted in the PubMed database for patients with intracranial DAVFs complicated with brainstem engorgement. Results: Sixty-eight articles reporting of 86 patients were included for final analysis. The patients were aged from 20 to 76 years (57.10 ± 12.90, n = 82). The female to male ratio was 0.68 (35:51). Thirty-three (40.2%, 33/82) patients were initially misdiagnosed as other diseases. The specific location distributions were cranio-cervical junction, cavernous sinus, superior petrosal sinus, transverse and/or sigmoid sinus, tentorium, and other sites in 27 (32.5%), 11 (13.2%), 9 (10.8%), 10 (12.0%), 21 (25.3%), and 5 (6.0%) patients, respectively. The Cognard classification of DAVFs were II, III, IV, and V in 9 (10.7%, 9/84), 1 (1.2%, 1/84), 1 (1.2%, 1/84), and 73 (86.9%, 73/84) patients. Eighteen (22%, 18/82) patients were demonstrated to have stenosis or occlusion of the draining system distal to the fistula points. The mean follow-up period was 7.86 (n = 74, range 0-60 months) months. Fifty-four (70.1%, 54/77) patients experienced a good recovery according to the mRS score. Conclusions: Intracranial DAVFs complicated with brainstem engorgement are rare entities. Initial misdiagnosis and delayed definite diagnosis are common in the past three decades. The treatment outcome is still unsatisfactory at present. Early awareness of this rare entity and efficiently utilizing the up to date investigations are of utmost importance.

Abstract: A long tortuous course of the abducens nerve (ABN) crossing a highly curved siphon of the internal carotid artery is of interest to neurosurgeons for cavernous sinus surgery. Although a “straight” intracavernous carotid artery in fetuses can change into an adult-like siphon in infants, there is no information on when or how the unique course of ABN is established. Histological observations of 18 near-term fetuses (12 specimens of frontal sections and 6 specimens of sagittal sections) demonstrated the following: (I) the ABN consistently took a straight course crossing the lateral side of an almost straight intracavernous carotid artery; (II) the straight course was maintained when sympathetic nerves joined; (III) few parasellar veins of the developing cavernous sinus separated the ABN from the ophthalmic nerve; and (IV) immediately before the developing tendinous annulus for a common origin of extraocular recti, the ABN bent laterally to avoid a passage of the thick oculomotor nerve. Since the present observations strongly suggested morphologies at birth and in infants, major angulations of the ABN as well as the well-known course independent of the other nerves in the cavernous sinus seemed to be established during childhood. In the human body, the ABN might be a limited example showing a drastic postnatal change in course. Consequently, it might be important to know the unique course of ABN before performing endovascular interventions and skull base surgery for petroclival and cavernous sinus lesions without causing inadvertent neurovascular injuries to neonates or infants.

Abstract: Objective To describe the endoscopic and microsurgical anatomy of the cavernous sinus (CS) with focus on the surgical landmarks in microsurgical anatomy. Materials and methods Ten formalin-fixed central skull base specimens (20 CSs) with silicone-injected carotid arteries were examined through an extended endoscopic transsphenoidal approach. Fifteen formalin-fixed heads were dissected to simulate the surgical position in CS approaches. Results Endoscopic access enables identification of the anterior and posterior surgical corridors. Structures within the CS and on its lateral wall could be visualized and studied, but none of the triangular areas relevant to the transcranial microsurgical anatomy were fully visible through the endoscopic approach. Conclusion The endoscopic approach to the CS is an important surgical technique for the treatment of pathological conditions that affect this region. Correlating endoscopic findings with the conventional (transcranial) microsurgical anatomy is a useful way of applying the established knowledge into a more recent operative technique. Endoscope can provide access to the CS and to the structures it harbors.