Microsurgical management of large and giant paraclinoid aneurysms

Microsurgical treatment of ophthalmic artery aneurysm, a case series of 55 patients with long-term follow-up

BACKGROUND

Ophthalmic artery aneurysm (OAA) can be secured in endovascular or microsurgical approaches. Still there are controversies in technique selection and their long term outcomes.

METHODS

All the patients with OAA were treated microsurgically and followed. Demographic data, neurological status, physical examination findings, angiographic data, operation details, and intraoperative and postoperative events were recorded and analyzed. P < 0.05 was considered significant.

RESULTS

Among 55 patients, 38 were females (69.1%). Median preoperative glasgow coma scale (GCS), Fisher Grade, and Hunt and Hess(HH) scores were 15, 1 and 1, respectively. The most common neurologic manifestation was visual problems (n = 15). The most common anatomical projection was medial (43.6%) oriented lesions. 85.5% of them only had 1 ophthalmic aneurysm while multiple aneurysms were reported in 14.6%. In 52 patients temporary clip was used. in 21 patients (38.2%) intraoperative aneurysm rupture occurred. Larger aneurysm size and preoperative hydrocephalus were associated with higher rates of aneurysm rupture (P = 0.003 and 0.031). 28.5% of the patients with visual problems had clinical improvement in the postoperative period. The mean follow-up period was 5 years. Follow-up angiography showed a 100% obliteration rate with a 0.0% recurrence rate. Median values for follow-up glasgow outcome scale and modified Rankin scale were 5 and 0, respectively. favorable neurological outcomes were associated with better primary GCS and HH scores.

CONCLUSION

OAA microsurgery is an effective and safe procedure with significant improvement in both visual and neurological status. Low recurrence rate and excellent clinical recovery are the most important advantages of microsurgery in OAA treatment.

Optic Foraminotomy versus Anterior Clinoidectomy for Small Superior-Projecting Paraclinoid Aneurysms: Visual and Angiographic Outcome Evaluation

INTRODUCTION

Optic foraminotomy (OF) has been recently proposed as an alternative to anterior clinoidectomy (AC) for selected types of paraclinoid aneurysms. In this study, OF and AC were compared for small superior-projecting paraclinoid aneurysms assuming visual and angiographic results as outcome measures. Indications for OF are also discussed.

METHODS

Data of patients who underwent surgery for a paraclinoid aneurysm in the last 10 years were collected across 3 tertiary hospitals. Small to regular-size and superior projecting aneurysms were sorted. Multiple and complex aneurysms were excluded. Records of patients who went through OF were compared with those of patients who underwent AC. Neurologic outcome was reported as a modified Rankin Scale. Aneurysm complete occlusion rate and rate of approach-related worsened vision were selected as outcome measures of efficacy and safety, respectively, of the OF versus AC. Unpaired t test and χ2 test were used for numerical and categorical variables, respectively. A P value less than 0.05 was considered statistically significant.

RESULTS

OF and AC groups involved 18 and 25 patients, respectively. Complication rate, overall neurologic outcome, rate of approach-related worsened vision, and complete occlusion rate did not differ between the groups. The average follow-up was 51 ± 34 and 60 ± 41 months in the OF and AC groups, respectively.

CONCLUSIONS

Compared to AC, OF did not show either a higher rate of approach-related worsened vision or a lower aneurysm complete occlusion rate. OF can be considered a valid alternative to the AC for small superior-projecting dorsal ICA wall paraclinoid aneurysms.

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.

Avoiding Complications in Aneurysm Ligation: Operative Tips and Tricks

Preventing possible complications during brain aneurysm surgery is mandatory to ensure a better outcome for patients. Currently, it is possible to rely on some technologic innovations such as motor evoked potential, endoscope-assisted surgery, dye with indocyanine green, and video angiography capable of supporting the surgeon's work. The innovation process has mainly assisted the endovascular technique compared with surgery. The latter, apart from some new technical expedients, always requires anatomic knowledge and optimal technical preparation. A careful patient selection, adequate surgical exposure, use of microsurgical techniques in expert hands, and meticulous postoperative management represent the key to success for the surgical treatment of cerebral aneurysms.

Reproducibility of a new classification of the anterior clinoid process of the sphenoid bone

BACKGROUND

Pneumatization of the anterior clinoid process (ACP) affects paraclinoid region surgery, this anatomical variation occurs in 6.6-27.7% of individuals, making its preoperative recognition essential given the need for correction based on the anatomy of the pneumatized process. This study was conducted to evaluate the reproducibility of an optic strut-based ACP pneumatization classification by presenting radiological examinations to a group of surgeons.

METHODS

Thirty cranial computer tomography (CT) scans performed from 2013 to 2014 were selected for analysis by neurosurgery residents and neurosurgeons. The evaluators received Google Forms with questionnaires on each scan, DICOM files to be manipulated in the Horos software for multiplanar reconstruction, and a collection of slides demonstrating the steps for classifying each type of ACP pneumatization. Interobserver agreement was calculated by the Fleiss kappa test.

RESULTS

Thirty CT scans were analyzed by 37 evaluators, of whom 20 were neurosurgery residents and 17 were neurosurgeons. The overall reproducibility of the ACP pneumatization classification showed a Fleiss kappa index of 0.49 (95% confidence interval: 0.49-0.50). The interobserver agreement indices for the residents and neurosurgeons were 0.52 (0.51-0.53) and 0.49 (0.48-0.50), respectively, and the difference was statistically significant (P < 0.00001).

CONCLUSION

The optic strut-based classification of ACP pneumatization showed acceptable concordance. Minor differences were observed in the agreement between the residents and neurosurgeons. These differences could be explained by the residents' presumably higher familiarity with multiplanar reconstruction software.

An Anatomic Feasibility Study for Revascularization of the Ophthalmic Artery, Part I: Intracanalicular Segment

BACKGROUND

The anatomico-functional complexity of the ophthalmic segment aneurysms is attributable to the presence of critical neurovascular structures in the surgical field. Surgical clipping of the ophthalmic artery (OpA) aneurysms can result in postoperative visual deficit due to the complexity of the aneurysm, vasospasm, or optic nerve manipulation. In this study, we aimed to characterize the feasibility of an intracanalicular OpA (iOpA) revascularization with 2 donor vessels: an intracranial-intracranial (IC-IC) bypass using the anterior temporal artery (ATA) and an extracranial-intracranial (EC-IC) bypass using the superficial temporal artery (STA). We further discuss their potential role in "unclippable" OpA aneurysms.

METHODS

Twenty cadaveric specimens were used to evaluate the operative exposure of the intradural and intracanalicular OpA segments using an extradural-intradural intracanalicular approach. The arterial caliber and length at the anastomotic sites and required donor artery lengths were measured. The feasibility of the bypass using both donors was assessed.

RESULTS

The average length of the intradural and intracanalicular segment of the OpA was 9.5 ± 1.6 mm. The mean caliber of the iOpA was 1.5 ± 0.2 mm. The mean ATA length required for an ATA-OpA anastomosis was 26.7 ± 8.9 mm, with a mean caliber of 1.0 ± 0.1 mm. The mean length of STA required for the bypass was 89.9 ± 9.7 mm, with a mean caliber of 1.92 ± 0.4 mm.

CONCLUSIONS

This study confirms the feasibility of iOpA revascularization using IC-IC and EC-IC bypasses. These techniques could potentially be used for prophylactic or therapeutic neuroprotection from retinal ischemic injury while treating complex OpA aneurysms, infiltrative tumors, or intraoperative arterial injuries.

Autologous Transfusion of Blood Aspirated during Suction Decompression in Clipping of Large or Giant Cerebral Aneurysm

The suction decompression (SD) method, which proactively aspirates the blood flowing into the aneurysm and reduces the internal pressure of the aneurysm, is useful for clipping surgery of large and giant cerebral aneurysm. However, there has been little discussion on re-utilization of blood aspirated during SD. This study aimed to examine the safety, convenience, and usefulness of autologous transfusion of aspirated blood using a transfusion bag. At the time of craniotomy, the cervical carotid artery is fully exposed. An angiocatheter sheath was inserted into the carotid artery and placed in the internal carotid artery. In SD, blood was aspirated from the sheath at a constant speed and quickly stored in a blood transfusion storage bag. Blood aspiration was repeated with a new syringe; once the transfusion bag was full, the blood was re-administered to the patient. Changes in vital sign and hemoglobin/hematocrit values before and after SD were examined in five cases performed in this procedure. The aspirated blood volumes of five cases ranged from 130 to 400 mL, and all aspirated blood was successfully re-transfused. There was no critical change in vital sign, and no significant decrease in the hemoglobin/hematocrit value. No findings suggestive of complications of thrombus formation, infection, and hemolysis were noted. Re-transfusion of aspirated blood during SD using a transfusion bag is a simple and safe method, which can minimize potential risk of re-utilizing aspirated blood, and enables the safe and easy execution of SD regardless of aspirated blood volume.

Review of Avoidance of Complications in Cerebral Aneurysm Surgery: The Fujita Experience

Avoidance of complications during cerebral aneurysm surgery marks the future outcome in the patient. Various modalities such as adequate opening of the Sylvian fissure, motor-evoked potential, endoscope-assisted microsurgery, indocyanine green dye, and dual image video angiography are available to reduce these complications during surgery, either by prevention of injury to the small perforators or the parent artery. We present our experience at the Fujita Health University Banbuntane Hospital, Japan, of the cerebral aneurysm surgery along with the use of these modalities in our patients from September 2014 to December 2016 along with a brief review of the various techniques for avoidance of complications.

Early and midterm results of treatment of giant internal carotid artery paraclinoid aneurysms with trapping and flow diverters

BACKGROUND

Flow diverter devices (FDD) carry risks of postoperative complications when treating aneurysms with wide necks, stenosis, and severe tortuosity of the parent vessel. In this study, we evaluated early and midterm results for the treatment of giant paraclinoid aneurysms managed by trapping and endovascular deployment of FDD.

METHODS

Medical records were analyzed for patients with giant paraclinoid aneurysms treated between July 2008 and December 2017 at National Centre for Neurosurgery with either a flow diverter or by trapping the aneurysm with or without extracranial-intracranial (EC-IC) bypass surgery. We recorded age, sex, clinical presentation, treatment modality, morbidity, and mortality. Clinical outcomes were assessed using a modified Rankin scale (mRS).

RESULTS

Among 29 consecutive patients, 13 were treated with FDD, and 16 patients were managed by trapping the aneurysm, where 7/16 cases had preliminary EC-IC bypass. Of 16 trapping patients, six were trapped endovascularly and ten were trapped surgically. During the follow-up period (mean 33 months, range 6-96), total exclusion of the aneurysm from the circulation was observed 100% of aneurysms in the trapping group and 84.6% in the FDD group (P = 0.192). Early postoperative morbidity was observed in three (23%) cases in the FDD group, and four (25%) in trapping group (P = 0.525). The FDD group had one (7.7%) fatal complication due to stent occlusion and severe ischemic stroke after three months postoperatively, despite appropriate antiplatelet therapy. There were no mortalities in the trapping group (P = 0.149). The rate of mRS 0-2 did not differ significantly across groups at discharge (81.3% vs. 69.2%; P = 0.667), and all patients had mRS 0-2 at follow-up (P = 1.000).

CONCLUSIONS

FDD deployment for giant paraclinoid aneurysms results in comparable angiographic and clinical outcomes to aneurysm trapping. Despite implementation of modern endovascular treatment methods, aneurysm trapping remains a valuable treatment option in carefully selected patients with giant paraclinoid aneurysms.

Application of indocyanine green video angiography in vascular neurosurgery

Indocyanine green video angiography (ICG-VA) is a non-invasive, easy to use and very useful tool for various neurosurgical procedures. The first application was in neurovascular surgery, because it was born as an intravascular tracer for vessels visualization; this has been really useful in aneurysms, atero-venous malformations (AVMs) and dural fistulas surgery where identification, obliteration or patency of vessels is essential. Introduced in vascular neurosurgery since 2003, ICG-VA applications have broadened over time, both in vascular and in other neurosurgical fields. In 2003 Raabe et al. have been the first to describe the use of ICG-VA for intraoperative assessment of cerebral vascular flow, enabling visualization of vessel patency and aneurysm occlusion during aneurysm surgery. ICG-VA applications in vascular neurosurgery have significantly increased over time including complex aneurysms, bypass, atero-venous malformations (AVM) artero-venous fistulas (AVF), evaluation of cortical perfusion. The procedure can be easily repeated after 5-10 minutes. Adverse reactions are comparable to those of other types of contrast media, with frequencies of 0.05% (hypotension, arrhythmia, or, more rarely, anaphylactic shock) to 0.2% (nausea, pruritus, syncope, or skin eruptions. The aim of the present study was to systematically analyze ICG-VA applications in vascular neurosurgery, highlighting the reported advantages and disadvantages, and discussing future perspectives.

The 25th anniversary of the retrograde suction decompression technique (Dallas technique) for the surgical management of paraclinoid aneurysms: historical background, systematic review, and pooled analysis of the literature

OBJECTIVE

Paraclinoid internal carotid artery (ICA) aneurysms frequently require temporary occlusion to facilitate safe clipping. Brisk retrograde flow through the ophthalmic artery and cavernous ICA branches make simple trapping inadequate to soften the aneurysm. The retrograde suction decompression (RSD), or Dallas RSD, technique was described in 1990 in an attempt to overcome some of those treatment limitations. A frequent criticism of the RSD technique is an allegedly high risk of cervical ICA dissection. An endovascular modification was introduced in 1991 (endovascular RSD) but no studies have compared the 2 RSD variations.

METHODS

The authors performed a systematic review of MEDLINE/PubMed and Web of Science and identified all studies from 1990-2016 in which either Dallas RSD or endovascular RSD was used for treatment of paraclinoid aneurysms. A pooled analysis of the data was completed to identify important demographic and treatment-specific variables. The primary outcome measure was defined as successful aneurysm obliteration. Secondary outcome variables were divided into overall and RSD-specific morbidity and mortality rates.

RESULTS

Twenty-six RSD studies met the inclusion criteria (525 patients, 78.9% female). The mean patient age was 53.5 years. Most aneurysms were unruptured (56.6%) and giant (49%). The most common presentations were subarachnoid hemorrhage (43.6%) and vision changes (25.3%). The aneurysm obliteration rate was 95%. The mean temporary occlusion time was 12.7 minutes. Transient or permanent morbidity was seen in 19.9% of the patients. The RSD-specific complication rate was low (1.3%). The overall mortality rate was 4.2%, with 2 deaths (0.4%) attributable to the RSD technique itself. Good or fair outcome were reported in 90.7% of the patients.Aneurysm obliteration rates were similar in the 2 subgroups (Dallas RSD 94.3%, endovascular RSD 96.3%, p = 0.33). Despite a higher frequency of complex (giant or ruptured) aneurysms, Dallas RSD was associated with lower RSD-related morbidity (0.6% vs 2.9%, p = 0.03), compared with the endovascular RSD subgroup. There was a trend toward higher mortality in the endovascular RSD subgroup (6.4% vs 3.1%, p = 0.08). The proportion of patients with poor neurological outcome at last follow-up was significantly higher in the endovascular RSD group (15.4% vs 7.2%, p < 0.01).

CONCLUSIONS

The treatment of paraclinoid ICA aneurysms using the RSD technique is associated with high aneurysm obliteration rates, good long-term neurological outcome, and low RSD-related morbidity and mortality. Review of the RSD literature showed no evidence of a higher complication rate associated with the Dallas technique compared with similar endovascular methods. On a subgroup analysis of Dallas RSD and endovascular RSD, both groups achieved similar obliteration rates, but a lower RSD-related morbidity was seen in the Dallas technique subgroup. Twenty-five years after its initial publication, RSD remains a useful neurosurgical technique for the management of large and giant paraclinoid aneurysms.

The role of indocyanine green videoangiography with FLOW 800 analysis for the surgical management of central nervous system tumors: an update

OBJECTIVE

Indocyanine green videoangiography (ICG-VA) is an intraoperative technique used to highlight vessels in neurovascular surgery. Its application in the study of the vascular pathophysiology in CNS tumors and its role in their surgical management are still rather limited. A recent innovation of ICG-VA (i.e., the FLOW 800 algorithm integrated in the surgical microscope) allows a semiquantitative evaluation of cerebral blood flow. The aim of this study was to evaluate for the first time the systematic application of ICG-VA and FLOW 800 analysis during surgical removal of CNS tumors.

METHODS

Between May 2011 and December 2017, all cases in which ICG-VA and FLOW 800 analysis were used at least one time before, during, or after the tumor resection, and in which surgical videos were available, were retrospectively reviewed. Results of the histological analysis were analyzed together with the intraoperative ICG-VA with FLOW 800 in order to investigate the tumor-related videoangiographic features.

RESULTS

Seventy-one patients who underwent surgery for cerebral and spinal tumors were intraoperatively analyzed using ICG-VA with FLOW 800, either before or after tumor resection, for a total of 93 videoangiographic studies. The histological diagnosis was meningioma in 25 cases, glioma in 14, metastasis in 7, pineal region tumor in 5, hemangioblastoma in 4, chordoma in 3, and other histological types in 13 cases. The authors identified 4 possible applications of ICG-VA and FLOW 800 in CNS tumor surgery: extradural surveys allowed exploration of sinus patency and the course of veins before dural opening; preresection surveys helped in identifying pathological vascularization (arteriovenous fistulas and neo-angiogenesis) and regional venous outflow, and in performing temporary venous clipping tests, when necessary; postresection surveys were conducted to evaluate arterial and venous patency and parenchymal perfusion after tumor removal; and a premyelotomy survey was conducted in intramedullary tumors to highlight the posterior median sulcus.

CONCLUSIONS

The authors found ICG-VA with FLOW 800 to be a useful method to monitor blood flow in the exposed vessels and parenchyma during microsurgical removal of CNS tumors in selected cases. In particular, a preresection survey provides useful information about pathophysiological changes of brain vasculature related to the tumor and aids in the individuation of helpful landmarks for the surgical approach, and the postresection survey helps to prevent potential complications associated with the resection (such as local hypoperfusion or venous infarction).

Entire Orifice Blocking-Assisted Microsurgical Treatment: Clipping of Intracranial Giant Wide-Neck Paraclinoid Aneurysms

OBJECTIVE

Giant wide-neck paraclinoid aneurysms remain a formidable challenge for neurosurgeons due to the brisk retrograde blood flow during surgical clipping. Theoretically, Entire orifice blockade (EOB) by placing a longitudinal intracarotid balloon catheter across the aneurysm neck could achieve a good vascular control in treating cerebral aneurysms, but related studies have been scarce. The aim of this study was to evaluate the safety and efficiency of the EOB-assisted microsurgical technique for treating giant wide-neck paraclinoid aneurysms.

METHODS

Clinical data and treatment summaries of patients with giant wide-neck paraclinoid aneurysms who underwent EOB-assisted microsurgical clipping were retrospectively reviewed.

RESULTS

A total of 26 patients were analyzed. All but 3 patients harbored unruptured aneurysms. The mean largest diameter of the aneurysms was 26.8±2.0 mm, and the mean neck size was 12.5±2.4 mm. All lesions were successfully clipped without residual aneurysms. Post-operative images revealed no major branch occlusion due to thromboembolic complications. Four patients presented neurologic deficits caused by vasospasm, 3 of which were completely resolved by postoperative treatment. At a mean follow-up time of 1.86 ± 0.95 years (range, 0.5-3.5 years), none of the patients died, and 96.2% (n = 25) of the patients had favorable clinical outcomes with modified Rankin Scale values of 0-2.

CONCLUSIONS

For patients with giant wide-neck paraclinoid aneurysms, EOB-assisted microsurgical clipping is a safe and useful procedure for obtaining vascular control, for softening and shrinking the aneurysm sac and for providing a wide and clean operative field that allows the clip to be effectively placed.

Vision outcomes in patients with paraclinoid aneurysms treated with clipping, coiling, or flow diversion: a systematic review and meta-analysis

OBJECTIVE

Patients with paraclinoid aneurysms commonly present with visual impairment. They have traditionally been treated with clipping or coiling, but flow diversion (FD) has recently been introduced as an alternative treatment modality. Although there is still initial aneurysm thrombosis, FD is hypothesized to reduce mass effect, which may decompress the optic nerve when treating patients with visually symptomatic paraclinoid aneurysms. The authors performed a meta-analysis to compare vision outcomes following clipping, coiling, or FD of paraclinoid aneurysms in patients who presented with visual impairment.

METHODS

A systematic literature review was performed using the PubMed and Web of Science databases. Studies published in English between 1980 and 2016 were included if they reported preoperative and postoperative visual function in at least 5 patients with visually symptomatic paraclinoid aneurysms (cavernous segment through ophthalmic segment) treated with clipping, coiling, or FD. Neuroophthalmological assessment was used when reported, but subjective patient reports or objective visual examination findings were also acceptable.

RESULTS

Thirty-nine studies that included a total of 2458 patients (520 of whom presented with visual symptoms) met the inclusion criteria, including 307 visually symptomatic cases treated with clipping (mean follow-up 26 months), 149 treated with coiling (mean follow-up 17 months), and 64 treated with FD (mean follow-up 11 months). Postoperative vision in these patients was classified as improved, unchanged, or worsened compared with preoperative vision. A pooled analysis showed preoperative visual symptoms in 38% (95% CI 28%–50%) of patients with paraclinoid aneurysms. The authors found that vision improved in 58% (95% CI 48%–68%) of patients after clipping, 49% (95% CI 38%–59%) after coiling, and 71% (95% CI 55%–84%) after FD. Vision worsened in 11% (95% CI 7%–17%) of patients after clipping, 9% (95% CI 2%–18%) after coiling, and 5% (95% CI 0%–20%) after FD. New visual deficits were found in patients with intact baseline vision at a rate of 1% (95% CI 0%–3%) for clipping, 0% (95% CI 0%–2%) for coiling, and 0% (95% CI 0%–2%) for FD.

CONCLUSIONS

To the authors’ knowledge, this is the first meta-analysis to assess vision outcomes after treatment for paraclinoid aneurysms. The authors found that 38% of patients with these aneurysms presented with visual impairment. These data also demonstrated a high rate of visual improvement after FD without a significant difference in the rate of worsened vision or iatrogenic visual impairment compared with clipping and coiling. These findings suggest that FD is an effective option for treatment of visually symptomatic paraclinoid aneurysms.

A long-term study of durability and risk factors for aneurysm recurrence after microsurgical clip ligation

OBJECTIVE

With the recent evolution of endovascular therapies, objective evaluation of the efficacy of clip ligation for cerebral aneurysms should be performed. This study was undertaken to evaluate the durability of microsurgical clip ligation, identify risk factors for recurrence, and assess the need for long-term follow-up imaging.

METHODS

A retrospective review of medical records identified 616 consecutive patients (156 male and 460 female patients; mean age 48.4 ± 12.4 years; range 6–90 years) who underwent microsurgical clip ligation and follow-up imaging at least 1 year after discharge between 1990 and 2010 at our institution. Of a total of 926 aneurysms in 616 patients, 758 aneurysms were microsurgically clip-ligated. At presentation, 431 of these aneurysms were ruptured and 327 aneurysms were unruptured. All patients underwent postoperative baseline imaging within the 1st month of their operation. A logistic regression analysis was performed to identify which variables are more likely to predict recurrence.

RESULTS

Late follow-up angiographic imaging was obtained at a mean of 7.2 ± 4.7 years postdischarge (median 5.7 years; range 1–23 years). Of the 699 clipped aneurysms without residua, late follow-up angiography revealed only 1 (0.14%) recurrent aneurysm. Of the 59 residual aneurysms that remained after initial clip ligation on early postoperative imaging, 8 (13.6%) demonstrated growth. All of these aneurysms required treatment. None of the recurrences were due to broken or delayed displacement of clips. A total of 111 patients presented with multiple aneurysms. De novo aneurysm formation occurred in 8 (0.97%) patients, all of whom initially presented with multiple aneurysms.

CONCLUSIONS

This study provides additional evidence to support the long-term efficacy of aneurysm clip ligation. The chance of aneurysm recurrence after complete clip ligation is very small. However, there is a regrowth risk of 1.83% per year for aneurysm remnants after incomplete clip ligation. These findings support the necessity for continued followup, late angiographic imaging, and the potential need for further intervention of incompletely ligated aneurysms. Furthermore, completely clip-ligated aneurysms may not require additional surveillance imaging unless multiple aneurysms were evident at presentation.

The outcome of a surgical protocol based on ischemia overprotection in large and giant aneurysms of the anterior cerebral circulation

Aiming to define the optimal treatment of large and giant aneurysms (LGAs) in the anterior circulation, we present our surgical protocol and patient outcome. A series of 42 patients with intracavernous LGAs (n = 16), paraclinoid (C2) LGAs (n = 17), and peripheral (middle cerebral artery—MCA or anterior cerebral artery—ACA) LGAs (n = 9) were treated after bypass under motor evoked potential (MEP) monitoring. Preoperatively, three categories of ischemic tolerance during internal carotid artery (ICA) occlusion were defined on conventional angiography: optimal, suboptimal, and insufficient collaterals. Accordingly, three types of bypass: low flow (LFB), middle flow (MFB) and high flow (HFB) were applied for the cases with optimal, suboptimal, and insufficient collaterals, respectively. Outcome was evaluated by the Glasgow Outcome Scale (GOS). All patients had excellent GOS score except one, who suffered a major ischemic stroke immediately after surgery for a paraclinoid lesion. Forty-one patients were followed up for 87.1 ± 40.1 months (range 13–144 months). Intracavernous LGAs were all treated by proximal occlusion with bypass surgery. Of paraclinoid LGA patients, 15 patients had direct clipping under suction decompression and other 2 patients with recurrent aneurysms had ICA (C2) proximal clipping with HFB. MEP monitoring guided for temporary clipping time and clip repositioning, observing significant MEP changes for up to 6 min duration. Of 9 peripheral LGAs patients 7 MCA LGAs had reconstructive clipping (n = 4) or trapping (n = 3) with bypass including LFB in 3 cases, MFB in 1 and HFB in 1. Two ACA LGAs had clipping (n = 1) or trapping (n = 1) with A3-A3 bypass. The applied protocol provided excellent results in intracavernous, paraclinoid, and peripheral thrombosed LGAs of the anterior circulation.

Endoscopic endonasal control of the paraclival internal carotid artery by Fogarty balloon catheter inflation: an anatomical study

OBJECTIVE Neurosurgical management of many vascular and neoplastic lesions necessitates control of the internal carotid artery (ICA). The aim of this study was to investigate the feasibility of achieving control of the ICA through the endoscopic endonasal approach by temporary occlusion with a Fogarty balloon catheter. METHODS Ten endoscopic endonasal paraseptal approaches were performed on cadaveric specimens. A Fogarty balloon catheter was inserted through a sellar bony opening and pushed laterally and posteriorly extraarterially along the paraclival carotid artery. The balloon was then inflated, thus achieving temporary occlusion of the vessel. The position of the catheter was confirmed with CT scans, and occlusion of the ICA was demonstrated with angiography. The technique was performed in 2 surgical cases of pituitary macroadenoma with cavernous sinus invasion. RESULTS Positioning the Fogarty balloon catheter at the level of the paraclival ICA was achieved in all cadaveric dissections and surgical cases through a minimally invasive, quick, and safe approach. Inflation of the Fogarty balloon caused interruption of blood flow in 100% of cases. CONCLUSIONS Temporary occlusion of the paraclival ICA performed through the endoscopic endonasal route with the aid of a Fogarty balloon catheter may be another maneuver for dealing with intraoperative ICA control. Further clinical studies are required to prove the efficacy of this method.

Emergency Non-occlusive High Capacity Bypass Surgery for Ruptured Giant Internal Carotid Artery Aneurysms

AIM

Managing ruptured giant internal carotid artery (ICA) aneurysms in an emergency situation is very challenging. By reporting two cases, we discuss the role of the Excimer Laser-assisted Non-occlusive Anastomosis (ELANA) technique as an armamentarium for cerebrovascular surgeons dealing with giant ICA aneurysms presenting with subarachnoid hemorrhage (SAH).

MATERIALS AND METHODS

The management of two consecutive patients treated with ELANA bypass during a 6-month period (June- December 2013) for ruptured giant ICA aneurysms in an emergency setting is presented.

RESULTS

The two patients presented with SAH and newly diagnosed giant ICA aneurysms (both Fisher 3; WFNS scores 2 and 4, respectively). Both patients received an emergent high-capacity extra- to intracranial (EC-IC) bypass with interposition of a saphenous vein graft between the external carotid artery (ECA) and the ICA-termination. The intracranial anastomosis was performed by the use of the non-occlusive ELANA technique. The aneurysms were successfully trapped, and there were no major complications and no major persistent morbidity in either patient. A good clinical outcome was obtained with a modified Rankin scale of 2 at the last follow-up in both patients.

CONCLUSION

Emergency ELANA bypass surgery is a useful instrument for managing patients with giant ICA aneurysms presenting with SAH. In experienced hands, the technique does not seem to carry increased risk and may expand the surgical options due to its non-occlusive nature.

Visual outcomes of endovascular and microsurgical treatment for large or giant paraclinoid aneurysms

BACKGROUND

The optimal treatment for large or giant paraclinoid aneurysms is still controversial. The present study evaluated the results of endovascular coiling and microsurgical clipping with special reference to visual outcomes.

METHODS

The clinical data and treatment outcomes of 39 cases of large (>15 mm) paraclinoid aneurysms were retrospectively reviewed. Presenting symptoms were subarachnoid hemorrhage in 16 aneurysms and visual impairment in 18. Twenty-one aneurysms were treated by endovascular therapy and 18 were treated by direct surgery.

RESULTS

Maximal aneurysm diameter ≥25 mm and preoperative visual acuity <20/100 were significantly related to poor visual outcome in univariate analysis. However, preoperative visual acuity was the only significant prognostic factor in multivariate analysis (odds ratio [OR] 0.12, 95 % confidence interval [CI] 0.01-0.95, p = 0.04). Although patients treated with endovascular coiling tended to have more favorable outcome than those with surgical clipping, adjustment for other confounding factors reduced the OR of favorable outcome following each treatment modality to nearly one (OR 1.14, 95 % CI 0.17-7.46, p = 0.89). Deteriorations in the visual field showed different patterns: upper visual field deficit after endovascular coiling, and inferior nasal quadrantanopia after microsurgical clipping.

CONCLUSIONS

Preoperative visual acuity was the only independent predictor of visual outcome in patients with large paraclinoid aneurysms. Although adjusted visual outcomes with microsurgical clipping and endovascular coiling were almost the same, selection of the optimal treatment for each aneurysm is essential with recognition of the potential risks and mechanisms of visual impairment.

Endovascular treatment of the distal internal carotid artery large aneurysm

Objective

According to the development of endovascular technique and devices, larger aneurysms on the distal internal carotid artery (ICA) can be treated using a less invasive method. The authors report on clinical and angiographic outcomes of these aneurysms treated using an endovascular technique.

Materials and Methods

Data on 21 patients with large aneurysms at distal ICA treated by endovascular method between January 2005 and December 2012 were included in this retrospective analysis.

Results

Clinical outcome of patients showed strong correlation with the initial neurologic status (p < 0.05). Aneurysm morphology showed saccular, fusiform, and wide-neck in 12, six and three patients. Six patients underwent stent assisted coiling and the other 15 patients underwent simple coiling. Aneurysm occlusion was performed immediately after embolization with near-complete (Raymond class 1-2) in 20 patients (95.2%) and incomplete (Raymond class 3) in one patient (4.8%). Delayed thrombotic occlusion occurred in two patients and their clinical result was fatal. Another five patients died in the hospital, from massive brain edema and/or increased intracranial pressure due to initial subarachnoid hemorrhage. Overall mortality was 30% (seven out of 21). Fatal complication related to the endovascular procedure occurred in two patients with thrombosis at middle cerebral artery (one with stent, the other without it).

Conclusion

Recent developed endovascular device and technique is safe enough and a less invasive method for distal large or giant aneurysms. Based on our analysis of the study, we suspect that coil embolization of large distal ICA aneurysms (with or without stenting) is effective and safe.

Clinical outcome of paraclinoid internal carotid artery aneurysms after microsurgical neck clipping in comparison with endovascular embolization

OBJECTIVE

Because of the complex anatomical association among vascular, dural, and bony structures, paraclinoid internal carotid artery (ICA) aneurysms remain a major challenge for vascular neurosurgeons. We studied the clinical outcomes of 61 paraclinoid ICA aneurysms after microsurgical clipping in comparison with endovascular coiling.

MATERIALS AND METHODS

Between January 2008 and December 2012, we treated 61 paraclinoid ICA aneurysms created by surgical clipping or endovascular coiling. Preoperative neurologic status and postoperative outcome were evaluated using the Glasgow coma scale (GCS) and the modified Rankin scale (mRS). Postoperative hydrocephalus and vasospasm were reviewed using the patients' medical charts.

RESULTS

Most patients were in good clinical condition before the operations and had good treatment outcomes. Clinical vasospasm was observed after the operation in five patients, and hydrocephalus occurred in six patients. No statistically significant difference regarding aneurysm size, sex, GCS score, H-H grade, and mRS was observed between the surgical clipping group and the endovascular coiling group. In addition, the treatment results and complications did not show statistically significant difference in either group.

CONCLUSION

Surgical occlusion of paraclinoid ICA aneurysms is difficult; however, no significant differences were observed in the treatment results or complications when compared with coil embolization. In particular, use of an adequate surgical technique may lead to better outcomes than those for coil embolization in the treatment of large and/or wide-neck paraclinoid ICA aneurysms.

Efficacy and outcomes of perioperative anesthetic management of extracranial to intracranial bypass for complex intracranial aneurysm in the absence of advanced neurological monitoring

Background and Aims:

Anesthetic management of extracranial to intracranial (EC-IC) bypass for complex intracranial aneurysms is challenging as the goals involve balancing the cerebral perfusion during parent artery clamping and avoiding factors that predispose to rupture of the unsecured aneurysm. There is very sparse literature available on anesthetic management for this procedure.

Materials and Methods:

A retrospective review of the records of 20 patients undergoing EC-IC bypass was performed with an objective of assessing the efficacy and outcomes of anesthetic management in the absence of advanced neurological monitoring.

Results:

A total of 20 patients underwent EC-IC bypass as an adjunct cerebral revascularization in the management of complex intracranial aneurysms. Intraoperatively normotension and normocarbia were maintained. During the EC-IC bypass, when the temporary clamp was applied, mild hypertension (increase from baseline by 20%) and hypervolemia (central venous pressure increased to 12 mmHg) were maintained. Cerebral protection during temporary clipping of intracranial vessel was provided using moderate hypothermia to 34°C and intravenous thiopentone. Temporary clip time ranged from 15 min to 54 min (mean-25 min). All patients except one were extubated post-operatively (19/20 = 95%). None of the patients had rupture of aneurysm in the peri-operative period. Three patients developed neurologic events (3/20 = 15%). One patient had cerebral vasospasm and two patients developed cerebral infarction. Two patient subsequently improved and one succumbed to the neurological deterioration (mortality 1/20 = 5%).

Conclusion:

Adherence to the principal goals for the procedure, avoidance of hemodynamic fluctuations such as hypotension and hypertension, maintenance of normocarbia, and cerebral protection, result in favorable neurological outcome even in the absence of advanced neuromonitoring.

Carotid artery occlusion for the treatment of symptomatic giant carotid aneurysms: a proposal of classification and surgical protocol

Giant intracranial aneurysms are rare disorders that represent only 5% of all intracranial aneurysms; they have a wide variety of presentations including rupture, embolic effects, and mass effect symptoms that can mislead the diagnosis to tumors rather than aneurysms. Their treatment is difficult and carries higher morbidity and mortality than usual aneurysms due to their complex nature. This study involved retrospective analysis of data of 28 patients, managed between 2006 and 2012, suffering from giant internal carotid artery (ICA) aneurysms with various presenting symptoms, none of which was hemorrhage. They were all evaluated by BOT prior to any intervention; they were subjected to various treatment strategies including selective coiling, parent artery occlusion with or without bypass, aneurysm trapping with or without bypass, and patients were followed for a period ranging from 6 months to 5 years. Out of 26 patients with giant aneurysms with mass effects, 16 patients showed full recovery (61.5 %), 5 showed partial improvement (19.2 %), and 5 showed no change in mass effect symptoms (19.2 %). One patient died (3.5 %). Symptoms such as TIA or epistaxis showed complete recovery. This study shows that a well-designed protocol aiming at parent artery sacrifice will yield good to excellent results in managing ICA giant aneurysms, and it also shows that parent artery sacrifice is superior to other forms of treatment of these lesions regarding recurrence rates, morbidity, and mortality.

Internal carotid artery reconstruction using multiple fenestrated clips for complete occlusion of large paraclinoid aneurysms

Objective

Although surgical techniques for clipping paraclinoid aneurysms have evolved significantly in recent times, direct microsurgical clipping of large and giant paraclinoid aneurysms remains a formidable surgical challenge. We review here our surgical experiences in direct surgical clipping of large and giant paraclinoid aneurysms, especially in dealing with anterior clinoidectomy, distal dural ring resection, optic canal unroofing, clipping techniques, and surgical complications.

Methods

Between September 2001 and February 2012, we directly obliterated ten large and giant paraclinoid aneurysms. In all cases, tailored orbito-zygomatic craniotomies with extradural and/or intradural clinoidectomy were performed. The efficacy of surgical clipping was evaluated with postoperative digital subtraction angiography and computed tomographic angiography.

Results

Of the ten cases reported, five each were of ruptured and unruptured aneurysms. Five aneurysms occurred in the carotid cave, two in the superior hypophyseal artery, two in the intracavernous, and one in the posterior wall. The mean diameter of the aneurysms sac was 18.8 mm in the greatest dimension. All large and giant paraclinoid aneurysms were obliterated with direct neck clipping without bypass. With the exception of the one intracavenous aneurysm, all large and giant paraclinoid aneurysms were occluded completely.

Conclusion

The key features of successful surgical clipping of large and giant paraclinoid aneurysms include enhancing exposure of proximal neck of aneurysms, establishing proximal control, and completely obliterating aneurysms with minimal manipulation of the optic nerve. Our results suggest that internal carotid artery reconstruction using multiple fenestrated clips without bypass may potentially achieve complete occlusion of large paraclinoid aneurysms.

Treatment strategies for complex intracranial aneurysms: review of a 12-year experience at the university of cincinnati

Complex intracranial aneurysms (CIAs) include those classified as giant, those located in brain regions of technically difficult access, or that involve arterial trunks/branches, and/or have complicated wall structure. We reviewed retrospectively our management of such lesions in a 12-year period. From 1997 to 2009, 192 patients were admitted with CIAs (133 females, 59 males; average age 55 years); 128 presented with subarachnoid hemorrhage (SAH) and 64 with unruptured, symptomatic CIAs. The SAH group had 73 anterior- and 55 posterior-circulation aneurysms. Most frequent location was middle cerebral artery. Treatment strategies included clipping (65.6%), coiling/stenting (28.1%), bypass (3.1%), no treatment (3.1%). Coiling/stenting was exclusively used for posterior-circulation aneurysms. Outcomes were good (modified Rankin Scale [mRS] 0 to 2) in 54 patients (42.2%), fair (mRS = 3 to 4) in 38 (29.7%), and poor (mRS = 5 to 6) in 36 (28.1%). Among unruptured CIAs, there were 47 anterior- and 17 posterior-circulation aneurysms. Most frequent location was ophthalmic. Thirty (46.9%) were clipped, 19 (29.7%) coiled, 6 (9.4%) by-passed, 2 (3.1%) wrapped, and 7 (10.9%) had no treatment. Outcomes were good in 57 patients (89%) and fair in 7 (11%). Good outcomes were obtained in unruptured CIAs using a multidisciplinary approach. Ruptured CIAs carry a significantly worse prognosis than overall SAH patients.

The role of intraoperative micro-Doppler ultrasound in verifying proper clip placement in intracranial aneurysm surgery

INTRODUCTION

Aneurysmal subarachnoid hemorrhage constitutes a clinical entity associated with high mortality and morbidity. It is widely accepted that improper clip placement may have as a result of incomplete aneurysm occlusion and/or partial or complete obstruction of an adjacent vessel. Various modalities, including intraoperative or postoperative digital subtracting angiography, near-infrared indocyanine green angiography, micro-Doppler ultrasonography (MDU), and neurophysiological studies, have been utilized for verifying proper clip placement. The aim of our study was to review the role of MDU during aneurysmal surgery.

METHODS

A literature search was performed using any possible combination of the following terms: "aneurysm," "brain," "cerebral," "clip," "clipping," "clip malpositioning," "clip repositioning," "clip suboptimal positioning," "Doppler," "intracranial," "microsurgery," "micro-Doppler," "residual neck," "ultrasonography," "ultrasound," and "vessel occlusion". Additionally, reference lists from the retrieved articles were reviewed for identifying any additional articles. Case reports and miniseries were excluded.

RESULTS

A total of 19 series employing intraoperative MDU during aneurysmal microsurgery were retrieved. All studies demonstrated that MDU accuracy is extremely high. The highest reported false-positive rate of MDU was 2 %, while the false-negative rate was reported as high as 1.6 %. It has been demonstrated that the presence of subarachnoid hemorrhage, specific anatomic locations, and large size may predispose to improper clip placement. Intraoperative MDU's technical limitations and weaknesses are adequately identified, in order to minimize the possibility of any misinterpretations.

CONCLUSION

Intraoperative MDU constitutes a safe, accurate, and low cost imaging modality for evaluating blood flow and for verifying proper clip placement during microsurgical clipping.

Giant intracranial aneurysms: evolution of management in a contemporary surgical series

BACKGROUND

Many significant microsurgical series of patients with giant aneurysms predate changes in practice during the endovascular era.

OBJECTIVE

A contemporary surgical experience is presented to examine changes in management relative to earlier reports, to establish the role of open microsurgery in the management strategy, and to quantify results for comparison with evolving endovascular therapies.

METHODS

During a 13-year period, 140 patients with 141 giant aneurysms were treated surgically. One hundred aneurysms (71%) were located in the anterior circulation, and 41 aneurysms were located in the posterior circulation.

RESULTS

One hundred eight aneurysms (77%) were completely occluded, 14 aneurysms (10%) had minimal residual aneurysm, and 16 aneurysms (11%) were incompletely occluded with reversed or diminished flow. Three patients with calcified aneurysms were coiled after unsuccessful clipping attempts. Eighteen patients died in the perioperative period (surgical mortality, 13%). Bypass-related complications resulted from bypass occlusion (7 patients), aneurysm hemorrhage due to incomplete aneurysm occlusion (4 patients), or aneurysm thrombosis with perforator or branch artery occlusion (4 patients). Thirteen patients were worse at late follow-up (permanent neurological morbidity, 9%; mean length of follow-up, 23 ± 1.9 months). Overall, good outcomes (Glasgow Outcome Score 5 or 4) were observed in 114 patients (81%), and 109 patients (78%) were improved or unchanged after therapy.

CONCLUSION

A heavy reliance on bypass techniques plus indirect giant aneurysm occlusion distinguishes this contemporary surgical experience from earlier ones, and obviates the need for hypothermic circulatory arrest. Experienced neurosurgeons can achieve excellent results with surgery as the "first-line" management approach and endovascular techniques as adjuncts to surgery.

Early and long-term outcome of surgically treated giant internal carotid artery aneurysms--comparison with smaller aneurysms

BACKGROUND

Internal carotid artery (ICA) is predominant localization of giant intracranial aneurysms (GIAs). The rupture of GIA is supposed to be related to higher risk of poor clinical outcome. Although endovascular techniques are still being developed, they seem to be unsatisfactory in the mean of GIAs.

METHODS

Included in the retrospective analysis were 78 giant and 250 smaller surgically treated ICA aneurysms. Exclusion criteria were multiple and blood blister-like aneurysms. Neurological deficit on admission, clinical and radiological presentation, gender, age, segment of ICA, surgical methods, accessory techniques and complications were analyzed. Death rate and short- and long-term outcome of giant aneurysms were compared with smaller aneurysms and risk factors for mortality, unfavorable short- and long-term outcome were determined.

RESULTS

There was no difference in general and surgical complications between ICA aneurysm size groups, as well as in occurrence of newly diagnosed neurological deficit after the operation. There were similar mortality rates, proportion of unfavorable outcome, and low health related quality of life for giant and smaller aneurysms. A 12.2% death rate for all ICA aneurysms was achieved. Trapping method as well as Fisher grades 3 and 4 increased mortality risk in the smaller aneurysm group. No significant factors were related to an unfavorable outcome in the ruptured giant aneurysm group. Patients older than 65, Hunt-Hess grades 4 and 5, Fisher grade 4, and newly diagnosed deficit after operation were connected with unfavorable outcome in the ruptured smaller aneurysm group. Newly diagnosed neurological deficit was also an unfavorable outcome risk factor in both giant and smaller ICA unruptured aneurysms. No difference was noted in long-term health-related quality of life between the giant and smaller ICA groups. Higher age and presence of concomitant disease were independent factors affecting quality of life, although obtained data were incomplete.

CONCLUSIONS

The study breaks the stereotype of unfavorable giant ICA aneurysms treatment results. Mortality rate, short- and long-term outcome after the operation of giant and smaller ICA aneurysms are similar. Higher age, patients' condition at admission, and the amount of extravasated blood and trapping method are poor prognostic factors in patients with smaller ICA aneurysm.