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.

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.

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.

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.

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.

Direct Clipping of Paraclinoid Aneurysm in Conjunction with Extradural Anterior Clinoidectomy: Technical Nuance and Functional Outcome.

Objective Because of their anatomical features, treatment for paraclinoid aneurysms has remained to be challenging. Thus, the aim of this report is to prove the validity of our surgical method for unruptured paraclinoid aneurysms, together with surgical videos. Study Design Between August 2017 and November 2019, we were able to perform surgical clipping for 11 patients with unruptured paraclinoid aneurysm using a completely unified method. This study investigated the effect of surgery on multiple measures, including visual impairment, brain contusion, temporalis muscle atrophy, and multiple neurocognitive functions. Results Of the 67 unruptured aneurysms treated at our hospital, 17 were identified to be paraclinoid aneurysm, and 11 of them were treated by direct clipping using anterior clinoidectomy. Three were ophthalmic artery aneurysms, three were superior hypophyseal artery aneurysms, and five were anterior carotid wall aneurysms without branch projection. Only one patient had asymptomatic mild enlargement of the Marriott blind spots postoperatively. No brain contusion and temporalis muscle atrophy were observed in any cases. Only the Trail Making test (TMT) showed a significant worsening in the acute postoperative period: mean pre- and postoperative TMT scores were 59.1 ± 29.1 and 72.7 ± 37.3 for Part A ( p = 0.018) and 80.5 ± 35.5 and 93.8 ± 39.9 for Part B ( p = 0.030), respectively. However, it improved in the chronic phase. Conclusion We can conclude that our surgical method is safe and can be considered an acceptable treatment. Although surgical stress can cause temporary executive dysfunction shortly after surgery, this decline is temporary.

The Intersection Between the Oculomotor Nerve and the Internal Carotid Artery to Distinguish Extracavernous and Intracavernous Paraclinoid Aneurysms Using Anatomic Dissections-A New 3T Magnetic Resonance Imaging Protocol Confirmed by Three-Dimensionally Printed Biomodels.

OBJECTIVE: To evaluate the relationship between the oculomotor nerve (CNIII) and the internal carotid artery (ICA) as a new anatomic-radiologic landmark for distinguishing the exact location of a paraclinoid intracranial aneurysm (IA). METHODS: Microanatomic dissections were performed in 20 cavernous sinuses to evaluate the ICA paraclinoid region. Based on anatomic observations, a new magnetic resonance (MRI) protocol to classify paraclinoid aneurysms was proposed. MRI of 42 IAs from 34 patients was independently analyzed and classified as intracavernous, extracavernous, or transitional by 2 neuroradiologists. To validate the proposed MRI protocol, each IA was classified by a three-dimensionally (3D) printed biomodel and agreement with the radiologic classifications was evaluated. Of 42 IAs, 23 undergoing microsurgeries were also classified by direct visualization. RESULTS: We observed that the true cavernous sinus roof is defined by the carotid-oculomotor membrane, which has an intimate relationship with the intersection between the superior limit of the CNIII and the ICA. Based on this intersection, all 42 IAs were radiologically classified and agreement with the 3D printed biomodels was observed in 95% IAs. Concordance tests showed a statistically significant (P < 0.05) agreement between the classifications. All 23 IAs treated had the radiologic and 3D biomodel classification confirmed. CONCLUSIONS: The intersection between the ICA and the CNIII, which crosses it transversely in its entire diameter, is a reliable anatomic-radiologic landmark to correctly classify paraclinoid aneurysms. Through a new MRI protocol, it is possible to radiologically identify this intersection and to easily distinguish the intracavernous and extracavernous ICA paraclinoid aneurysms.

Intraoperative Angiogram Using C-Arm Fluoroscopy and Direct Common Carotid Artery Puncture During Surgical Treatment of Paraclinoid Aneurysms.

BACKGROUND: Intraoperative angiography (IOA) has been shown to be a useful adjunct in surgical treatment of cerebral aneurysms. However, its use can be limited by hybrid operating room availability. On the other hand, the use of C-arm fluoroscopy can add challenges to IOA during navigation of the aortic arch and selection of the great vessels. We aimed to describe a simple method of IOA that can be applied during surgery of paraclinoid aneurysms and can be performed in a normal operating room without the need to navigate the aortic arch. METHODS: In patients undergoing surgery for paraclinoid aneurysms with need for cervical carotid artery exposure, IOA was performed using a single plane C-arm fluoroscopy unit after direct puncture of the carotid artery. RESULTS: Five patients were included: 2 with subarachnoid hemorrhage, 2 with unruptured aneurysm and history of subarachnoid hemorrhage, and 1 with unruptured aneurysm. There were 2 internal carotid blister aneurysms, 2 ophthalmic artery aneurysms, and 1 superior hypophyseal artery aneurysm. IOA was performed using direct carotid puncture through the neck incision required for proximal control. In all cases, intraoperative images were of sufficient quality to determine the completeness of aneurysm occlusion as well as parent and branching vessel patency. There were no postoperative infarctions and no complications related to IOA. CONCLUSIONS: IOA using direct carotid puncture can be performed in a standard operating room with the use of a C-arm, eliminating the need to catheterize the great vessels of the aortic arch.

Endoscopic endonasal approach for simultaneously treating a pituitary adenoma coexisting with a paraclinoid aneurysm: illustrative case.

BACKGROUND: There is a certain incidence of pituitary adenomas coexisting with intracranial aneurysms, but a concurrent therapeutic strategy of tumor removal and aneurysm clipping via endoscopic endonasal approach is rarely reported. The indications and limitations of endoscopic endonasal approach surgery for this type of lesions are worth discussing. OBSERVATIONS: The case of a pituitary tumor coexisting with a paraclinoid aneurysm was reviewed. Using an endoscopic endonasal approach, the pituitary adenoma was completely excised with extrapseudocapsular separation technique, the aneurysm was clipped at the same time, and the skull base defect was reconstructed in multilayer fashion. No tumor recurrence was found, and aneurysm clipping was complete at the 6-month follow-up after surgery. LESSONS: For patients harboring a pituitary adenoma with a selected paraclinoid aneurysm, simultaneous tumor resection and aneurysm clipping via endoscopic endonasal approach are feasible. This strategy has the advantages of saving medical resources, promoting the patient's rapid postoperative recovery, and reducing possible antiplatelet therapy after interventional therapy. However, surgery needs to strictly follow the indications in experienced hands, and the therapeutic effect needs to be verified by more cases and longer follow-up results.

Increased Carotid Siphon Tortuosity Is a Risk Factor for Paraclinoid Aneurysms.

Background: Geometrical factors associated with the surrounding vasculature can affect the risk of aneurysm formation. The aim of this study was to determine the association between carotid siphon curvature and the formation and development of paraclinoid aneurysms of the internal carotid artery. Methods: Digital subtraction angiography (DSA) data from 42 patients with paraclinoid aneurysms (31 with non-aneurysmal contralateral sides) and 42 age- and gender-matched healthy controls were analyzed, retrospectively. Morphological characteristics of the carotid siphon [the posterior angle (α), anterior angle (ß), and Clinoid@Ophthalmic angle (γ)] were explored via three-dimensional rotational angiography (3D RA) multiplanar reconstruction. The association between carotid siphon morphology and the formation of paraclinoid aneurysms was assessed through univariate analysis. After this, logistic regression analysis was performed to identify independent risk factors for aneurysms. Results: Significantly smaller α, ß, and γ angles were reported in the aneurysmal carotid siphon group when compared with the non-aneurysmal contralateral healthy controls. The ß angle was best for discriminating between aneurysmal and non-aneurysmal carotid siphons, with an optimal threshold of 18.25°. By adjusting for hypertension, smoking habit, hyperlipidemia, and diabetes mellitus, logistic regression analysis demonstrated an independent association between the carotid siphons angles α [odds ratio (OR) 0.953; P < 0.05], ß (OR 0.690; P < 0.001), and γ (OR 0.958; P < 0.01) with the risk of paraclinoid aneurysms. Conclusions: The present findings provide evidence for the importance of morphological carotid siphon variations and the likelihood of paraclinoid aneurysms. These practical morphological parameters specific to paraclinoid aneurysms are easy to assess and may aid in risk assessment in these patients.

Stent-assisted coiling of unruptured paraclinoid aneurysms with wide neck or unfavorable dome-to-neck ratio: Results of ventral wall vs dorsal wall with propensity score matching analysis.

OBJECTIVE: This study aimed to evaluate the clinical safety and efficacy of stent-assisted coil embolization of unruptured wide-necked paraclinoid aneurysms based on the projection distribution. METHODS: Between November 2015 and September 2020, 267 unruptured paraclinod aneurysms in 236 patients were identified with a wide neck or unfavorable dome-to-neck ratio and treated with stent-assisted coiling technique. The classification of this segment aneurysms was simplified to the dorsal group (located on the anterior wall) and ventral group (Non-dorsal). Following propensity score matching analysis, the clinical and radiographic data were compared between the two groups. RESULTS: Among 267 aneurysms, 186 were located on the ventral wall and 81 were on the dorsal wall. Dorsal wall aneurysms had a larger size (p < .001), wider neck (p = .001), and higher dome-to-neck ratio (p = .023) compared with ventral wall aneurysms. Propensity score-matched analysis found that dorsal group had a significantly higher likelihood of unfavorable results in immediate (residual sac, 39.4% vs. 18.2%, p = .007) and follow-up angiography (residual sac, 14.8% vs. 1.9%, p = .037) compared with ventral group, with significant difference in recurrence rates (9.3% vs. 0%, p = .028). The rates of procedure-related complications were not significantly different, but one thromboembolic event occurred in the dorsal group with clinical deterioration. CONCLUSIONS: Traditional stent-assisted coiling can be given preference in paraclinoid aneurysms located on the ventral wall. The relatively high rate of recurrence in dorsal wall aneurysms with stent assistance may require other treatment options.

Hybrid Anterior Clinoidectomy in the Clipping of Paraclinoid Aneurysms: Technique, Utility and Case Illustration.

Background: Anterior clinoidectomy for aneurysm clipping is generally performed intradurally. Despite obvious advantages, accidental drill slippage or indirect damage from heat and bone dust remain major drawbacks. Objective: To demonstrate the surgical technique and utility of a combined extra- and intra-dural clinoidectomy in the clipping of dorsal wall paraclinoid internal carotid artery aneurysm. Material and Methods: A case of dorsal wall paraclinoid aneurysm which was stuck to the anterior clinoid process on preoperative angiogram is presented. The surgical technique is shown stepwise, and the intricacies of the technique are described. Results: The hybrid clinoidectomy allowed for proper delineation of the aneurysm, mobilization of the optic nerve and intracranial proximal control on the clinoidal segment by dint of "apparent" intracranial ICA lengthening. This allowed the aneurysm to be clipped successfully and the patient made an uneventful recovery. Conclusion: Hybrid clinoidectomy is a useful technique and must be learnt.

Endovascular treatment of medium and large intracranial aneurysms with large volume coils: A single-center experience.

BACKGROUND: Large volume coils are an alternative to conventional coils for the treatment of intracranial aneurysms. However, there are no published reports documenting occlusion and complication rates in medium and large intracranial aneurysms. Therefore, we present our results in this subgroup of aneurysms. METHODS: A single-center, retrospective analysis of consecutive patients treated with Penumbra coils 400 in aneurysms ≥7 mm was performed. Demographics, aneurysm features, procedural details, intraoperative complications, clinical outcomes, and occlusion rates were analyzed. RESULTS: Thirty-three patients were included for analysis, and a total of 33 intracranial aneurysms were analyzed. Mean age was 57.6 years (SD ± 12.4) and 85% of the patients were women. Large aneurysms represented 46% of cases. Paraclinoid (55%) followed by posterior communicating (30.3%) aneurysms was the most frequently treated. Ruptured and saccular aneurysms were found in 49% and 63% of the cases, respectively. The mean aneurysmal dimensions were 14.2 mm width, 11.9 mm length, 5.4 mm neck, and 2.4 dome-to-neck ratio. A dome-neck ratio <2 was identified in 39% of cases. The mean number of coils per aneurysm was 4.8. Immediate modified Raymond-Roy Grades 1, 2, and 3A were achieved in 15%, 21%, and 64%, respectively. Twenty-six patients were evaluated at a mean follow-up period of 11 months, with an adequate occlusion of 92% and a good clinical outcome (modified Rankin score ≤2) in 96% of patients. CONCLUSION: Endovascular treatment with PC400 coils is an effective and safe option for medium and large intracranial aneurysms with high occlusion rates, few complications, and good clinical outcomes at follow-up.

Large postoperative inflow area predictive of recurrence for paraclinoid aneurysms treated by simple coiling.

OBJECTIVES: This study aims to investigate recurrence risk factors of simply coiled unruptured paraclinoid aneurysms based on a porous medium model (POM). METHODS: Twenty unruptured coiled paraclinoid aneurysms with digital subtract angiography (DSA) follow-up were enrolled to analyze morphological and hemodynamic variables to predict recurrence. RESULTS: Recurrent aneurysms have larger neck areas than stable aneurysms (34.43 ± 21.46 mm2 vs. 16.12 ± 7.10 mm2; p = 0.048). For hemodynamic variables, recurrent aneurysms had larger preoperative (16.40 ± 11.38 mm2 vs. 7.87 ± 3.75 mm2; p = 0.048) and postoperative inflow areas (14.07 ± 6.80 mm2 versus 6.73 ± 4.20 mm2; p = 0.021) than the stable group. Only the postoperative inflow area (p = 0.031, OR = 1.289; 95% CI 1.024-1.624) was an independent predictor of recurrence after multivariate regression analysis. The receiver operating characteristic (ROC) curve analysis efficiently predicted recurrence (AUC = 0.833, p = 0.021) with an inflow area cutoff value (9.15 mm2; sensitivity, 0.833; specificity, 0.857). CONCLUSIONS: Neck area along with pre- and postoperative inflow areas were associated with aneurysm recurrence. These findings suggest that a large postoperative inflow area independently predicts the recurrence of coiled paraclinoid aneurysms.

Visual Impairment due to a large paraclinoid aneurysm treated with parent artery occlusion and bypass: A case report.

INTRODUCTION: Paraclinoid internal carotid artery (ICA) aneurysms can sometimes cause visual field disturbances due to their size, and it is challenging to treat either surgically or using endovascular techniques. Flow diverters generally have positive outcomes, but sometimes in symptomatic aneurysms, we see the thrombosed section becomes enlarged. Therefore, optimal treatment strategies are difficult to determine. CASE: A 68-year-old woman presented with a chief complaint of vision loss in the left eye. A large wide-necked saccular aneurysm was found on the left ICA paraclinoid portion. Under general anesthesia, a Pipeline Flex was inserted along with coil embolization. After treatment, the aneurysm showed thrombotic expansion, and the visual impairment worsened. One year later, aneurysm recanalization was evident; therefore, another Pipeline was inserted to overlap the stent. However, her visual impairment worsened again, and parent artery occlusion with high flow bypass was performed 20 months after her first treatment. Two weeks postoperatively, improved peripheral vision was confirmed. Further, no enlargement of the aneurysm was observed using magnetic resonance imaging 6 months later. CONCLUSION: This case examined a symptomatic, large paraclinoid aneurysm in a patient, which continued to enlarge after Pipeline stent placement, but was later treated successfully using direct parent artery occlusion in combination with high-flow bypass.