Visual dysfunction and neurodegeneration caused by severe inflammatory optic neuropathy after coil embolization of a paraclinoid aneurysm: illustrative case.

BACKGROUND: Visual impairment due to delayed optic neuropathy is a rare complication of the endovascular treatment of paraclinoid aneurysms. An inflammatory response induced in the treated aneurysm wall is a known mechanism underlying this pathophysiology. The authors describe a case with severe and progressive optic neuropathy leading to neuronal degeneration and severe visual dysfunction. OBSERVATIONS: A 42-year-old female with a history of surgical clipping for a paraclinoid aneurysm presented with a recurrence. Although the patient was unaware of any visual dysfunction, a preoperative ophthalmological examination revealed mild inferior quadrantanopia in the left eye. The coil embolization procedure was uneventful; however, the following day, the patient experienced progressive visual impairment, which worsened despite the initiation of steroid therapy. Ophthalmological examination revealed a severe decrease in visual acuity and further deterioration of the visual field. Magnetic resonance imaging showed remarkable swelling and edema of the left optic nerve adjacent to the treated aneurysm. Despite continued steroid therapy, the patient's visual function did not recover well due to subsequent optic nerve degeneration. LESSONS: Optic neuropathy after endovascular procedures can lead to severe visual dysfunction. Careful management is essential, particularly when treating a symptomatic paraclinoid aneurysm, even if symptoms are only apparent on detailed examination.

Bone anatomic variations of the parasellar region and its technical implications in para clinoid and posterior communicating segment aneurysms microsurgical clipping - Technical note.

Background: Microsurgical treatment of paraclinoid aneurysms is a complex task that generally requires anterior clinoid process (ACP) removal to obtain adequate surgical exposure. This procedure poses a considerable technical difficulty due to the association of the ACP to critical neurovascular structures. Furthermore, anatomical variations in the parasellar region, such as the caroticoclinoid foramen (CCF) or an interclinoid bridge (ICB), may impose additional challenges and increase surgical complications. The present study aims to briefly review some anatomic variations in the parasellar region and describe a step-by-step surgical technique for a hybrid anterior clinoidectomy based on the senior author's experience. Methods: We present two cases with bone variations on the parasellar region in patients with a paraclinoid aneurysm and another with a posterior communicating segment aneurysm treated by microsurgical clipping at our hospital. Results: We focused on safely dealing with these variations during surgery, without further complications, and with good postoperative results. Patients were discharged with no significant deficit. Postoperative control, computed tomography angiography showed complete exclusion of aneurysms. Conclusion: Although anatomical variations in the parasellar region can complicate surgical clipping of these aneurysms, it is essential to ensure the best possible surgical outcome to conduct thorough preoperative and radiological evaluations.

Case report: Mirror paraclinoid aneurysm associated with mirror clinoidal meningioma.

Introduction: Clinoidal meningiomas and paraclinoid aneurysms are individually uncommon, with the coexistence of mirror paraclinoid aneurysms and clinoidal meningiomas presenting an even rarer scenario. While the association between meningiomas and aneurysms is documented, the simultaneous presence of mirror lesions for both pathologies is not reported in the literature. Clinical presentation: We report a 62-year-old female with a three-month history of moderate bifrontal headaches. Magnetic Resonance Angiography (MRA) revealed mirror paraclinoid aneurysms, prompting surgical intervention. During the procedure, mirror clinoidal meningiomas were incidentally discovered. The left aneurysm was addressed first due to higher rupture risk, followed by the right aneurysm 3 months later. Both meningiomas were confirmed as Transitional Meningiomas (Grade 1; OMS, 2021). The aneurysms were successfully clipped, and the patient had an excellent postoperative outcome. Conclusion: This case represents a unique occurrence of mirror ophthalmic segment internal carotid artery aneurysms associated with mirror clinoidal meningiomas, a combination not previously reported. Despite the limitations of MRA in detecting small meningiomas, it remains a valuable non-invasive screening tool for neurovascular diseases. The case underscores the need for further research to elucidate the association between cerebral aneurysms and meningiomas.

Frequency and Characteristics of Paraclinoid Aneurysm in Ruptured Cerebral Aneurysms.

OBJECTIVE: This study aimed to determine the frequency of paraclinoid aneurysms among ruptured cerebral aneurysms and compare paraclinoid aneurysms with other aneurysms to clarify the characteristics of ruptured paraclinoid aneurysms. METHODS: This study included 970 ruptured cerebral aneurysms treated at our hospital between 2003 and 2020. RESULTS: There were 15 cases (1.3%) of paraclinoid aneurysms with maximum diameters of 5-22 mm (mean±standard deviation [SD], 11.6±5.4 mm). Treatment consisted of clipping in four patients and endovascular treatment in 11. Factors significantly different in multivariate analysis for paraclinoid aneurysms compared with those for other aneurysms were a history of hypertension (odds ratio [OR], 1.2-9.8; p=0.021) and aneurysm ≥10 mm (OR, 7.5-390.3; p<0.001). The sites of paraclinoid aneurysm were ophthalmic artery type in nine patients, anterior wall type in five, medial wall type in one, and ventral wall type in zero. The medial wall type (22 mm) was significantly larger than the ophthalmic artery type (mean±SD, 7.2±2.0 mm) (p=0.003), and the anterior wall type (mean±SD, 12.2±4.8 mm) was significantly larger than the ophthalmic artery type (p=0.024). CONCLUSION: This study showed a low frequency of paraclinoid aneurysms among ruptured cerebral aneurysms. Most were upward-facing with relatively large aneurysms, and no aneurysms were smaller than 5 mm. With recent advances in endovascular treatment devices, paraclinoid aneurysms are easily treatable. However, the treatment indication of each paraclinoid aneurysm should be carefully considered.

Clipping of Bilateral Ophthalmic Artery Aneurysms Through a Single Craniotomy.

Bilateral ophthalmic aneurysms are rare and involve two aneurysms in the ophthalmic arteries, one on each, leading to potential symptoms such as vision loss and headaches. The treatment options for aneurysms, ranging from surgery and endovascular embolization to observation, depend on various factors, including aneurysm size and the patient's health. Microsurgery, while presenting complexities due to the intricate anatomy of the anterior clinoid region, offers potential advantages such as enhanced decompression rates and reduced aneurysm recurrence. The presented surgical video illustrates the treatment of bilateral ophthalmic artery aneurysms via a single craniotomy. This method reduces surgical duration and trauma, facilitating quicker patient recovery. However, this method bears potential risks, especially to both optic nerves. As underscored in the video, the utmost anatomical understanding in the anterior clinoid area is pivotal for successful outcomes and reduced complications.

Paraclinoid internal carotid artery aneurysm with delayed stent occlusion after deployment of a flow diverter stent involving the orifice of the anterior cerebral artery: illustrative case.

BACKGROUND: In-stent thrombotic occlusion is a serious ischemic complication that can also result in ischemia in the distal perfusion territory and the territory of side branches for the artery in which the flow diverter (FD) stent is deployed. OBSERVATIONS: A 49-year-old female with a large paraclinoid internal carotid artery (ICA) aneurysm was treated with an FD involving the orifice of the anterior cerebral artery (ACA). The antiplatelet dose was reduced because of an increased clopidogrel response postintervention. The patient developed aphasia 2 months later. Emergency magnetic resonance imaging and digital subtraction angiography of the brain indicated FD stent occlusion and a small infarct in the distal vascular territory of the ipsilateral ICA, but the anterior choroidal artery (AChoA) territory was preserved by collateral flow. Emergency superficial temporal artery to middle cerebral artery anastomosis was performed, and she was discharged without neurological deficit 2 weeks after the second operation. LESSONS: In-stent occlusion after FD deployment involving the orifice of the ACA can cause severe cerebral ischemia that requires an adequate antiplatelet effect and careful follow-up. The AChoA territory can be preserved by collateral blood flow even in cases of in-stent occlusion.

Combined endoscopic endonasal and transcranial approach for internal carotid artery aneurysms: usefulness and safety of endonasal proximal control.

It is necessary to secure both the proximal and distal sides of the parent artery to prevent premature rupture when clipping cerebral aneurysms. Herein, we describe four cases in which the proximal internal carotid artery (ICA), affected by a paraclinoid aneurysm, was secured using an endoscopic endonasal approach. We used various tools, including a surgical video, cadaver dissection picture, artist's illustration, and intraoperative photographs, to elucidate the process. No patient experienced postoperative complications at our institution. Compared to the cervical or cavernous ICA, the ICA adjacent to the clivus (paraclival ICA) can be anatomically safely and easily exposed using an endoscopic endonasal approach because there is no need to consider cerebrospinal fluid leakage or hemorrhage from the cavernous sinus. Securing the proximal side of the parent artery using an endoscopic endonasal approach may be a viable method for clipping selected ICA aneurysms, such as paraclinoid aneurysms especially for upward or outward aneurysms of the C2 portion.

Paraclinoid aneurysms clipping through an extradural sphenoid ridge keyhole approach.

BACKGROUND: Paraclinoid aneurysms represent a challenge for neurosurgeons due to the anatomical complexity of this region. Then, innovative techniques such as the extradural sphenoid ridge approach are suitable for a safe microsurgical clipping. METHOD: A description of the surgical technique was made by the senior author, a vascular neurosurgeon experienced with the use of this approach in the management of paraclinoid aneurysms exemplified through a clinical case. CONCLUSION: Microsurgical clipping through an extradural sphenoid ridge keyhole approach for small and midsize paraclinoid aneurysms is an excellent treatment modality with good clinical and surgical results.

A Six-Surface System to Describe Anatomy of Anterior Clinoid Process and Its Application in Anterior Clinoidectomy and Resection of Paraclinoid Meningioma.

OBJECTIVE: The anterior clinoid process (ACP) is surrounded by nerves and vessels that, together, constitute an intricate anatomical structure with variations that challenges the performance of individualized anterior clinoidectomy in treating lesions with different extents of invasion. In the present study, we established a 6-surface system for the ACP based on anatomical landmarks and analyzed its value in guiding ACP drilling and resection of paraclinoid meningiomas. METHODS: Using the anatomical characteristics of 10 dry skull specimens, we set 9 anatomical landmarks to delineate the ACP into 6 surfaces. Guided by our 6-surface system and eggshell technique, 5 colored silicone-injected anatomical specimens were dissected via a frontotemporal craniotomy to perform anterior clinoidectomy. Next, 3 typical cases of paraclinoid meningioma were selected to determine the value of using our 6-surface system in tumor resection. RESULTS: Nine points (A-H and T) were proposed to delineate the ACP surface into frontal, temporal, optic nerve, internal carotid artery, cranial nerve III, and optic strut surfaces according to the adjacent tissues. Either intradurally or extradurally, the frontal and temporal surfaces could be identified and drilled into depth, followed by skeletonization of the optic nerve, cranial nerve III, internal carotid artery, and optic strut surfaces. After the residual bone was removed, the ACP was drilled off. In surgery of paraclinoid meningiomas, our 6-surface system provided great benefit in locating the dura, nerves, and vessels, thus, increasing the safety of opening the optic canal and relaxing the oculomotor or optic nerves and allowing for individualized ACP drilling for meningioma removal. CONCLUSIONS: Our 6-surface system adds much anatomical information to the classic Dolenc triangle and can help neurosurgeons, especially junior ones, to increase their understanding of the paraclinoid spatial structure and accomplish individualized surgical procedures with high safety and minimal invasiveness.

Endovascular Treatment and Microsurgical Clipping for the Management of Paraclinoid Intracranial Aneurysms: A Systematic Review and Meta-Analysis.

OBJECTIVE: We aimed to compare the efficacy and safety of microsurgical clipping versus endovascular treatment (EVT) for paraclinoid aneurysms. METHODS: A systematic search for studies including patients with paraclinoid aneurysms treated with a microsurgical or endovascular technique was conducted in 6 databases from inception to February 2022. Efficacy outcomes included complete angiographic occlusion at last follow-up, favorable functional outcome, and recurrence of the aneurysm. For safety, we assessed a composite of intraoperative and postoperative complications. Data were pooled using a random-effects model. RESULTS: A total of 95 studies including 6711 patients, 3029 in the surgical group and 3682 in the EVT group were found. Pooled rates of complete occlusion were 94% (95% CI 91%-96%; I2 = 0%) in the surgical group and 69% (95% CI 63%-74%; I2 = 79%) in the EVT group, respectively. The favorable functional outcome rate was 86% (95% CI 76%-92%; I2 = 72%) with surgical treatment and 95% (95% CI 92%-97%; I2 = 61%) with EVT. The rate of aneurysm recurrence with surgical treatment was 1% (95% CI 0%-4%; I2 = 0%) and 12% (95% CI 9%-16%; I2 = 57%) with EVT. The composite safety outcome rate in the surgical group was 24% (95% CI 18%-30%; I2 = 90%) and 10% (95% CI 8%-13%; I2 = 71%) in the EVT group. CONCLUSIONS: Our findings suggest that microsurgical clipping seems to have a higher efficacy than EVT in terms of angiographic occlusion and aneurysm recurrence; however, EVT seems to be safer in terms of intraoperative and postoperative complications. Considering the heterogeneity and low-level evidence of the data available, further prospective randomized studies are warranted to confirm our findings.

Supraorbital keyhole approach for paraclinoid aneurysms clipping: A case series with literature review.

Background: Paraclinoid aneurysms (PcAs) are challenging aneurysms due to the complexity of their relation to the surrounding bony and neurovascular structures. Although over the past decade, their management strategy has shifted from transcranial to endovascular approaches; here, we try to revolve around a subcategory to which minimal invasive supraorbital keyhole (SOK) surgery is feasible depending on specific radiological criteria with a literature review. Methods: A group of unruptured PcAs was managed surgically, with a subset that was clipped through the SOK approach. They were selected by preoperative simulation images using 3D computed tomography (CT) angiography (CTA). We also conducted an extensive literature review based on a database available on PubMed and Google Scholar, the yielded cases from the literature review plus our cases were analyzed according to six parameters including their size, location, dome direction, need for clinoidectomy and proximal cervical control, and surgical outcome. Results: From February 2009 to August 2022, 49 cases of unruptured PcAs were managed by clipping, and of these, four cases were clipped by the SOK approach, in addition, four cases were yielded through the literature review. The sizes of the PcAs ranged from 3 to 8 mm. Their location fluctuated from anterior to the superomedial wall and their domes pointed superiorly except for one which points posteriorly. Six of eight cases required anterior clinoidectomy, the outcome was uneventful. Conclusion: A subset of unruptured PcAs are amenable to SOK with criteria such as unruptured small aneurysm (<10 mm) and projected superiorly. These characteristics can be determined preoperatively using CTA.

Enterprise stents versus low-profile visualized intraluminal support stents for stent-assisted coiling of unruptured paraclinoid aneurysms.

BACKGROUND: The microsurgical treatment of paraclinoid aneurysms can be challenging due to the anatomical structures that surround them. OBJECTIVE: This study compared the clinical and angiographic outcomes of unruptured paraclinoid aneurysms treated with enterprise (EP) stents and low-profile visualized intraluminal support (LVIS) stents. METHODS: A retrospective analysis of the clinical and radiological data from 133 patients with 139 unruptured paraclinoid aneurysms, who received an EP or an LVIS stent between January 2017 and June 2021 at Taizhou People's Hospital, was performed. Immediate postoperative and follow-up angiographic results were analyzed retrospectively using the Raymond-Roy occlusion classification (RROC). Any complications following the procedure and the patients' clinical outcomes were noted. RESULTS: Enterprise stents were used for stent-assisted coiling in 64 patients with 68 aneurysms and LVIS stents were used in 69 patients with 71 aneurysms. Both groups exhibited an increase in the proportion of aneurysms meeting the criteria for RROC class I, but the LVIS group demonstrated a higher rate of aneurysms meeting the class I criteria compared with the EP group, both on immediate postoperative angiography (45.1% vs. 11.8%, p< 0.001) and on follow-up angiography (94.9% vs. 80.6%, p= 0.025). Procedure-related complications were experienced by 9.4% of patients in the EP group (one coil prolapse, two parent artery occlusions, and three thromboembolic events), and 8.7% of patients in the LVIS group (three stent-related thrombosis and three thromboembolic events). There were no statistically significant differences between the two groups in relation to perioperative complications (p= 0.746) or favorable clinical outcomes (p= 0.492). CONCLUSION: A greater proportion of aneurysms in the LVIS group met the criteria for RROC class I compared with the EP group. There is no significant difference in procedural complications or clinical outcomes between EP and LVIS stents. Although no aneurysm recurrence was observed during the short follow-up period, continued monitoring is required.

Endoscopic endonasal clipping of a medial paraclinoid aneurysm with roadmapping assistance: Two-dimensional operative video.

Background: Advancements in endoscopic endonasal approaches (EEAs) allow the treatment of a wide variety of diseases including vascular pathology. Case Description: A 56-year-old woman presented with thunderclap headache due to two aneurysms: Communicating segment of left internal carotid artery (ICA) and medial paraclinoid (Baramii IIIB). The ICA aneurysm was clipped through a conventional transcranial approach; the paraclinoid aneurysm was successfully clipped using an EEA guided with roadmapping assistance. Conclusion: EEA is useful to treat aneurysms in selected cases and the use of adjuvant angiographical techniques such as roadmapping or proximal balloon control allow excellent control during the procedure.

Visualization balloon occlusion-assisted technique in the treatment of large or giant paraclinoid aneurysms: A study of 17 cases series.

Objective: Although balloon-assisted techniques are valuable in aneurysm clipping, repeated angiography and fluoroscopy are required to understand the location and shape of the balloon. This study investigated the value of visualization balloon occlusion-assisted techniques in aneurysm hybridization procedures. Methods: We propose a visualization balloon technique that injects methylene blue into the balloon, allowing it to be well visualized under a microscope without repeated angiography. This study retrospects the medical records of 17 large or giant paraclinoid aneurysms treated by a visualization balloon occlusion-assisted technique in a hybrid operating room. Intraoperative surgical techniques, postoperative complications, and immediate and long-term angiographic findings are highlighted. Results: All 17 patients had safe and successful aneurysm clipping surgery with complete angiographic occlusion. Under the microscope, the balloon injected with methylene blue is visible through the arterial wall. The position and shape of the balloon can be monitored in real time without repeated angiography and fluoroscopic guidance. Two cases of intraoperative visualization balloon shift and slip into the aneurysm cavity were detected in time, and there were no cases of balloon misclipping or difficult removal. Of 17 patients, four patients (23.5%) experienced short-term complications, including pulmonary infection (11.8%), abducens nerve paralysis (5.9%), and thalamus hemorrhage (5.9%). The rate of vision recovery among patients with previous visual deficits was 70% (7 of 10 patients). The mean follow-up duration was 32.76 months. No aneurysms or neurological deficits recurred among all patients who completed the follow-up. Conclusion: Our study indicates that microsurgical clipping with the visualization balloon occlusion-assisted technique seems to be a safe and effective method for patients with large or giant paraclinoid aneurysms to reduce the surgical difficulty and simplify the operation process of microsurgical treatment alone.

How I do it: The microsurgical clipping of the giant paraclinoid aneurysm using the retrograde suction decompression technique.

BACKGROUND: Paraclinoid aneurysms account for 5.4% of all intracranial aneurysms. Giant aneurysms are found in 49% of these cases. The 5-year cumulative rupture risk is 40%. Microsurgical treatment of paraclinoid aneurysms is a complex challenge that requires a personalized approach. METHOD: Extradural anterior clinoidectomy and optic canal unroofing were performed in addition to orbitopterional craniotomy. Falciform ligament and distal dural ring transection provided the internal carotid artery and optic nerve mobilization. Retrograde suction decompression was used to soften the aneurysm. Clip reconstruction was performed using tandem angled fenestration and parallel clipping techniques. CONCLUSION: Orbitopterional approach with extradural anterior clinoidectomy combined with retrograde suction decompression technique is a safe and effective modality for treatment of giant paraclinoid aneurysms.

Efficacy of 3D evaluation of unruptured paraclinoid aneurysms within Leksell GammaPlan® for determination of their intradural localization.

BACKGROUND: Determination of the intradural unruptured paraclinoid aneurysm localization is difficult, but critical for selection of the optimal treatment strategy. OBJECTIVE: To assess efficacy of the three-dimensional (3D) evaluation of unruptured paraclinoid aneurysms within Leksell GammaPlan® (LGP; Elekta AB; Stockholm, Sweden) for determination of their intradural localization. METHODS: Overall, 125 incidentally diagnosed unruptured paraclinoid aneurysms in 118 patients (mean age, 55 years) underwent 3D evaluation of their localization within LGP using post-contrast thin-slice constructive interference in steady state (CISS) images, which in 41 cases were additionally co-registered and fused with the axial computed tomography angiography (CTA) source images. RESULTS: According to the evaluation within LGP, paraclinoid aneurysms were considered intradural, transitional, and extradural in 75, 25, and 25 cases respectively. Overall, 51 of 75 aneurysms deemed to be intradural, underwent microsurgical management, and intraoperative visual inspection confirmed their intradural localization in 45 cases, whereas it was transitional in 3, and extradural in 3. If during preoperative 3D evaluation within LGP only post-contrast CISS images were used, prediction of the pure intradural localization of aneurysm was correct in 88 % of cases (95 % CI: 79-97 %), and of the pure or partial (i.e., transitional) intradural localization in 94 % of cases (95 % CI: 88-100 %), whereas it was 100 % if co-registration and fusion of the contrast-enhanced CISS and CTA source images was done. CONCLUSION: Intradural localization of the unruptured paraclinoid aneurysms may be effectively predicted based on their 3D evaluation within LGP using post-contrast thin-slice CISS and CTA source images, which may help with clinical decision-making.

Risk factors for intraoperative in-stent thrombosis during stent-assisted coiling of paraclinoid aneurysms.

Objectives: To identify independent risk factors for intraoperative in-stent thrombosis (IST) in paraclinoid aneurysms (PAs). Methods: 172 PA patents undergoing stent-assisted coiling (SAC) were divided into an IST group (n = 12) and a non-IST group (n = 160). Clinical characteristics, aneurysm morphologies, and laboratory parameters were measured. We performed independent t tests (for normally distributed data) or non-parametric tests (for non-normally distributed data) to compare continuous parameters. Multivariate logistic regression analysis with a stepwise forward method was conducted to determine independent risk factors. Receiver operating characteristic curves were generated, and the Delong test was employed for comparisons. Results: Independent risk factors for IST included size ratio (SR) (p < 0.001, odds ratio [OR] = 3.909, confidence interval [CI] = 1.925-7.939), adenosine diphosphate (ADP) inhibition (p = 0.028, OR = 0.967, CI = 0.938-0.996), and reaction time (R) (p = 0.006, OR = 0.326, CI = 0.147-0.725). The combined factors (SR, ADP inhibition, and R) exhibited area under the curves of 0.870, 0.720, 0.716, and 0.697, with cutoff values of 2.46, 69.90%, and 4.65, respectively. Conclusion: The SR, ADP inhibition, and R values were independent risk factors for the IST in the PAs undergoing SAC. For PAs with a large SR, surgeons could prepare for long-term dual antiplatelet therapy before SAC.

Enterprise 2 Stent-Assisted Embolization of Paraclinoid Aneurysms: A Single Center Preliminary Study.

Objective: Enterprise stent has been widely used for assisted embolization in wide-necked aneurysms while delayed ischemia or thromboembolic complications for its incomplete stent apposition. The purpose of this study was to summarize and analyze the clinical experience of using Enterprise 2 (EP2) stent-assisted embolization in the treatment of paraclinoid aneurysms. Methods: From January 2019 to December 2020, the clinical and imaging data of 98 patients with paraclinoid aneurysms treated with EP2 stent-assisted embolization were enrolled retrospectively. Preliminary experience and follow-up outcomes of EP2 stent-assisted embolization of paraclinoid aneurysms were assessed by using the Raymond grade and modified Rankin Scale. Results: Of the 98 aneurysms, all stents were released satisfactorily. The immediate postprocedural angiography revealed a complete occlusion of the aneurysms with 77.55% of the (76/98) patients, and the last follow-up angiograms showed complete occlusion with 83.67% of the (82/98) patients. The average aneurysm size was (4.11 ± 1.25) mm, the aneurysm diameter was (4.41 ± 1.37) mm, the vessel radius was (3.87 ± 0.32) mm, the diameter at the distal of stent was (3.23 ± 0.21) mm, and the proximal was (4.18 ± 0.23) mm. Among the 98 aneurysms, 13 cases had incomplete stent apposition, 3 cases had intraoperative knotting, and the stents were improved post adjusted; 2 cases had vasospasm and 1 case had stenosis during operation, the symptoms were improved after symptomatic treatment. The result demonstrated that stent length and inner bending radius of parent artery were the pivotal factors affecting incomplete stent apposition (P < 0.01). Conclusion: The EP2 stent for the treatment of paraclinoid aneurysms is safe and effective, however, the length of the stent and the inner bending radius of parent artery are important factors affecting incomplete stent apposition.

Magnetic resonance imaging finding of coexistence of bilateral paraclinoid aneurysms in a patient with a nonfunctioning macroadenoma, simultaneous resection, and clipping: illustrative case.

BACKGROUND: Unruptured incidental intracranial aneurysm can coexist with pituitary adenoma, however, the occurrence is extremely rare. Timely diagnosis of asymptomatic intracranial aneurysms with pituitary adenoma may lead to planning a tailored surgical strategy to deal with both pathologies simultaneously. A case of a patient who underwent transcranial resection of a pituitary adenoma with clipping of two mirror aneurysms is reported. OBSERVATIONS: A 55-year-old female presented with deterioration of visual acuity that progressed over 1 year, as well as presence of right eyelid ptosis. Magnetic resonance imaging of the head showed the presence of an intrasellar pituitary macroadenoma. Bilateral paraclinoid aneurysms were documented to be in contact with the pituitary tumor. The patient underwent surgery with simultaneous aneurysm clipping and tumor resection through a standard pterional approach with intradural clinoidectomy. The aneurysms were successfully clipped after the tumoral debulking. After clipping, the pseudocapsule was fully resected. LESSONS: Various treatment options are available. Although endovascular securing of the aneurysms prior to the tumor resection would be ideal, in cases in which this resource is not readily available at all times, the surgeon must be prepared to solve pathologies with an elevated level of complexity.

Endoscopic Techniques in Vascular Neurosurgery.

This section reviews the selection criteria and best practices for endoscopic cerebrovascular surgery, focusing on purely endoscopic endonasal approaches. Although these approaches still play a limited role in open vascular neurosurgery, they offer a robust and potentially safer technique for establishing visualization and vascular control of particular, well-selected pathologies, such as aneurysms of the proximal circulation; this requires strong, multidisciplinary experience with endoscopic anatomy and surgical technique, advanced reconstruction techniques, and instruments designed to be maneuvered within this relatively novel corridor and application.