Intracavernous Internal Carotid Artery Research Articles

Variants of the Anterior Subtemporal Approach to the Gasserian Ganglion and Related Structures: An Anatomical Study With Relevant Implications for Keyhole Surgery

The advantages and limitations of different craniotomy positions and approach trajectories to the gasserian ganglion (GG) and related structures using an anterior subtemporal approach have not been studied systematically. Knowledge of these features is of importance when planning keyhole anterior subtemporal (kAST) approaches to the GG to optimize access and minimize risks. Eight formalin-fixed heads were used bilaterally to assess temporal lobe retraction (TLR), trigeminal exposure, and relevant anatomical aspects of extra- and transdural classic anterior subtemporal (CLAST) approaches compared with slightly dorsally and ventrally allocated corridors. TLR to the GG and foramen ovale was found to be lower via the CLAST approach (P < 0.001). Using the ventral variant, TLR to access the foramen rotundum was minimized (P < 0.001). The overall TLR was maximal using the dorsal variant (P < 0.001) owing to interposition of the arcuate eminence. An extradural CLAST approach required wide exposure of the greater petrosal nerve (GPN) and middle meningeal artery (MMA) sacrifice. Both maneuvers were spared using a transdural approach. Using CLAST, medial dissection >39 mm can enter the Parkinson triangle, jeopardizing the intracavernous internal carotid artery. The ventral variant enabled access to the anterior portion of the GG and foramen ovale without the need for MMA sacrifice or GPN dissection. The CLAST approach provides high versatility to approach the trigeminal plexus, minimizing TLR. However, an extradural approach jeopardizes the GPN and requires MMA sacrifice. The risk of cavernous sinus violation exists when progressing medially beyond 4 cm. The ventral variant has some advantages to access the ventral structures and avoid MMA and GPN manipulation. In contrast, the usefulness of the dorsal variant is rather limited owing to the greater TLR required.

A Case of Large Intracavernous Internal Carotid Artery Aneurysm with Acute Spontaneous Thrombosis and Parent Artery Pseudo-occlusion

A Case of Large Intracavernous Internal Carotid Artery Aneurysm with Acute Spontaneous Thrombosis and Parent Artery Pseudo-occlusion

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.

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). 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. 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. 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.

Blood Supply of Cranial Nerves Passing Through the Cavernous Sinus: An Anatomical Study and Its Implications for Microsurgical and Endoscopic Cavernous Sinus Surgery.

BackgroundDespite improvements in surgical techniques, cranial nerve (CN) deficits remain the most frequent cause of disability following cavernous sinus (CS) surgery. The most common tumor affecting the CS is meningioma. They originate from lateral wall and have their blood supply from meningohypophyseal trunk (MHT) and inferolateral trunk (ILT). Pituitary adenomas commonly invade the CS through its medial wall and receive blood supply form medial branches of the internal carotid artery (ICA) (superior and inferior hypophyseal arteries). Some tumors may grow within the CS (e.g. trigeminal schwannomas, hemangiomas). These tumors are fed by all the intracavernous ICA branches. Tumors involving the CS may also displace the neurovascular structures, therefore, a better understanding of intracavernous neurovascular anatomy may reduce the postoperative morbidity associated with approaching CS tumors. In this anatomical study, the anatomic variations and their clinical implications of the intracavernous CNs’ blood supply were evaluated through transcranial and endonasal routes.MethodsTwenty sides of ten adult cadaveric formalin-fixed, latex-injected specimens were dissected in stepwise fashion under microscopic and endoscopic magnification. The origin and course of the intracavernous ICA branches supplying the intracavernous CNs are studied.ResultsThe proximal segment of the oculomotor nerve receives blood supply from the ILT in 85%, and the tentorial artery of the MHT in 15% of specimens. The distal segment is exclusively supplied by the ILT. The proximal trochlear nerve receives blood supply from the ILT (75%) and the tentorial artery (25%); the distal segment is exclusively supplied by the superior orbital branch. The proximal third of the abducens nerve receives its vascularity exclusively from the dorsal meningeal artery, and its middle and distal thirds from the ILT. The ophthalmic and proximal maxillary segments of the trigeminal nerve also receive blood supply from the ILT. The distal maxillary segment is supplied by the artery of the foramen rotundum. All ILT branches terminate on the inferomedial aspects of the intra-cavernous CNs. Extensive anastomoses are found between ILT branches and the branches arising from external carotid artery.ConclusionUnderstanding the anatomy of the intracavernous ICA’s branches is important to improving surgical outcomes with tumors involving the CS.

Microsurgical Anatomy of the Inferomedial Paraclival Triangle: Contents, Topographical Relationships and Anatomical Variations.

The inferomedial triangle is one of the two surgical triangles in the paraclival subregion of the skull base. It is delineated by the posterior clinoid process, the dural entrance of the trochlear nerve and the dural entrance of the abducens nerve. The aim of the present article is to describe the anatomical variations within the inferomedial triangle. Measurements of the triangle’s borders and area were supplemented by detailed observations of the topographical anatomy and various arrangements of its contents. Nine adult cadaveric heads (18 sides) and 28 sagittal head sections were studied. The mean area of the inferomedial triangle was estimated to be 60.7 mm2. The mean lengths of its medial, lateral and superior borders were 16.1 mm, 11.9 mm and 10.4 mm, respectively. The dorsal meningeal artery was identified within the inferomedial triangle in 37 out of 46 sides (80.4%). A well-developed petrosphenoidal ligament of Grüber was identified within the triangle on 36 sides (78.3%). Although some structures were variable, the constant contents of the inferomedial triangle were the posterior petroclinoid dural fold, the upper end of the petroclival suture, the gulfar segment of the abducens nerve and the posterior genu of the intracavernous internal carotid artery.

Temporary Clipping of the Intracavernous Internal Carotid Artery: A Novel Technique for Proximal Control.

Securing proximal control in complex paraclinoid aneurysm surgery through traditional techniques may be challenging and risky in certain situations. Advancements of anatomical knowledge of the cavernous sinus (CS) and hemostasis have made it more accessible as a surgical option. To describe the technique of temporary clipping of the horizontal segment of the intracavernous internal carotid artery (IC-ICA) in preparation for permanent clipping of complex paraclinoid aneurysms. Through an extradural pretemporal approach, the lateral wall of the CS is exposed. The dura between the trochlear nerve and V1 is opened, and access is made to the horizontal segment of the IC-ICA. After circumferential dissection, the temporary clip can be introduced to the artery, and the extradural clinoidectomy can be continued under secured proximal control. Seven patients with complex paraclinoid aneurysms were treated between May 2013 and May 2016 by the senior author. Temporary clipping of the IC-ICA was performed in all cases. Average time to achieve proximal control was 22.6 min (22.6±13.8). One patient developed transient oculomotor palsy postoperatively. There were no other complications. When the exposed clinoidal segment of the internal carotid artery does not offer sufficient proximal space for temporary clipping, the extradural approach can be extended to the horizontal portion of the IC-ICA. In our experience, this technique is a quick, reliable, and safe alternative to the classical modalities of temporary occlusion.

Intracavernous Internal Carotid Artery Aneurysm Presenting as Acute Diplopia: A Case Report

IntroductionDiplopia is an uncommon emergency department (ED) complaint representing only 0.1% of visits, but it has a large differential. One cause is a cranial nerve palsy, which may be from a benign or life-threatening process.Case ReportA 69-year-old female presented to the ED with two days of diplopia and dizziness. The physical exam revealed a sixth cranial nerve palsy isolated to the left eye. Imaging demonstrated an intracavernous internal carotid artery aneurysm. The patient was treated with embolization by neurointerventional radiology.DiscussionThe evaluation of diplopia is initially divided into monocular, usually from a lens problem, or binocular, indicating an extraocular process. Microangiopathic disease is the most common cause of sixth nerve palsy; however, more serious etiologies may be present, such as an intracavernous internal carotid artery aneurysm, as in the patient described. Imaging modalities may include computed tomography or magnetic resonance imaging.ConclusionSome causes of sixth nerve palsy are benign, while others will require more urgent attention, such as consideration of an intracavernous internal carotid artery aneurysm.

Complications Associated With Transsphenoidal Pituitary Surgery: Review of the Literature.

Complications Associated With Transsphenoidal Pituitary Surgery: Review of the Literature.

Review of the main surgical and angiographic-oriented classifications of the course of the internal carotid artery through a novel interactive 3D model

The course of the internal carotid artery (ICA) and its segment classifications were reviewed by means of a new and freely available 3D interactive model of the artery and the skull base, based on human neuroimages, that can be freely downloaded at the Public Repository of the University of Barcelona (http://diposit.ub.edu/dspace/handle/2445/112442) and runs under Acrobat Reader in Mac and Windows computers and Windows 10 tablets. The 3D-PDF allows zoom, rotation, selective visualization of structures, and a predefined sequence view. Illustrative images of the different classifications were obtained. Fischer (Zentralbl Neurochir 3:300-313, 1938) described five segments in the opposite direction to the blood flow. Gibo-Rothon (J Neurosurg 55:560-574, 1981) follow the blood flow, incorporated the cervical and petrous portions, and divided the subarachnoid course-supraclinoid-in ophthalmic, communicating, and choroidal segments, enhancing transcranial microscopic approaches. Bouthillier (Neurosurgery 38:425-433, 1996) divided the petrous portion describing the lacerum segment (exposed in transfacial procedures and exploration of Meckel's cave) and added the clinoid segment between the proximal and distal dural rings, of interest in cavernous sinus surgery. The Kassam's group (2014), with an endoscopic endonasal perspective, introduces the "paraclival segment," including the "lacerum segment" and part of the intracavernous ICA, and details surgical landmarks to minimize the risk of injury. Other classifications are also analyzed. This review through an interactive 3D tool provides virtual views of the ICA and becomes an innovative perspective to the segment classifications and neuroanatomy of the ICA and surrounding structures.

Pathophysiology of carotid-cavernous fistulas in vascular Ehlers-Danlos syndrome: a retrospective cohort and comprehensive review

BackgroundVascular Ehlers-Danlos syndrome (vEDS) is a rare condition characterized by connective tissue fragility. Direct spontaneous carotid-cavernous fistula (sCCF) is reportedly pathognomonic of vEDS. We conducted this study to understand the possible mechanisms of occurrence of sCCF in this subset of patients.MethodsWe conducted a retrospective analysis of a monocentric vEDS cohort along with a literature review regarding sCCF in this condition.ResultsOf 133 patients regularly followed in our centre between 2000 and 2017, 13 (9.8%) had a diagnosis of direct sCCF (92.3% female, median age 33.0 years, interquartile range (IQR) [26.0–39.5]). There were 7 Glycine missense and 6 splice-site variants but no variant leading to haploinsufficiency. The literature search identified 97 vEDS patients with direct sCCF (79.4% female, 7.2% sex not reported, median age 31.0 years, IQR [24.0–39.0]). Increased carotid circumferential wall stress, higher carotid distensibility and lower carotid intima-media thickness could contribute to a higher risk for direct sCCF in vEDS. There is no predictive factor for the occurrence of sCCF apart from female sex in vEDS.ConclusionsIn vEDS, anatomical and pathophysiological features of the intra-cavernous internal carotid artery make it prone to shunting in the cavernous sinus, due either to a spontaneous rupture or to a spontaneous dissection with pseudoaneurysm formation. Direct sCCF in seemingly healthy young individuals should be highly suggestive of vEDS and prompt further investigation.

Intra cavernous aneurysm of internal carotid artery masquerading as a pituitary adenoma: a case report

BackgroundPituitary dysfunction in adults are often associated with tumors of the gland and manifests with mass effects and hypopituitarism. MRI of pituitary region often provides confirmation of the diagnosis and assists in planning neurosurgery.Case presentationA 69 years old female evaluated for chronic headache was found to have a supra-sellar mass lesion that mimicked a pituitary tumor, with biochemical evidence of hypopituitarism. Cerebral angiogram confirmed the diagnosis of an aneurysm of the intracavernous internal carotid artery. She was successfully treated with coil embolization of the aneurysm and achieved resolution of symptoms and return of biochemistries to normal.ConclusionCarotid aneurysm can mimc pituitary tumours clinically and radiologically on MRI scan. This rare possibility should be considered in evaluating supra-sellar masses to avoid catastrophic consequences.

First Application of 7-T Magnetic Resonance Imaging in Endoscopic Endonasal Surgery of Skull Base Tumors

Successful endoscopic endonasal surgery for the resection of skull base tumors is reliant on preoperative imaging to delineate pathology from the surrounding anatomy. The increased signal-to-noise ratio afforded by 7-T MRI can be used to increase spatial and contrast resolution, which may lend itself to improved imaging of the skull base. In this study, we apply a 7-T imaging protocol to patients with skull base tumors and compare the images with clinical standard of care. Images were acquired at 7 T on 11 patients with skull base lesions. Two neuroradiologists evaluated clinical 1.5-, 3-, and 7-T scans for detection of intracavernous cranial nerves and internal carotid artery (ICA) branches. Detection rates were compared. Images were used for surgical planning and uploaded to a neuronavigation platform and used to guide surgery. Image analysis yielded improved detection rates of cranial nerves and ICA branches at 7 T. The 7-T images were successfully incorporated into preoperative planning and intraoperative neuronavigation. Our study represents the first application of 7-T MRI to the full neurosurgical workflow for endoscopic endonasal surgery. We detected higher rates of cranial nerves and ICA branches at 7-T MRI compared with 3- and 1.5-T MRI, and found that integration of 7 T into surgical planning and guidance was feasible. These results suggest a potential for 7-T MRI to reduce surgical complications. Future studies comparing standardized 7-, 3-, and 1.5-T MRI protocols in a larger number of patients are warranted to determine the relative benefit of 7-T MRI for endonasal endoscopic surgical efficacy.

Long-term results of cabergoline therapy for macroprolactinomas and analyses of factors associated with remission after withdrawal.

Withdrawal of cabergoline is generally challenging, especially in patients with large or invasive macroprolactinomas. Therefore, we aimed to assess long-term results of cabergoline therapy for macroprolactinomas and remission achievement results after withdrawal in patients with macroprolactinomas. We also investigated clinical characteristics and factors related to remission after withdrawal. This was an institutional review board-approved retrospective analysis. We studied 46 macroprolactinoma patients who had taken cabergoline during the period from 2003 through 2013. Administration of cabergoline was maintained for 5 years before withdrawal. Median follow-up after the initiation of cabergoline therapy was 54·3 (range 5·3 to 137·2) months. Recurrences of hyperprolactinaemia were observed in 3 of 11 (27%) postwithdrawal patients at a median time of 3·0 (range; 2·9-11·2) months, indicating that a high percentage (73%) maintained remission for at least 12 months after cabergoline cessation. Factors significantly associated with remission were analysed in 21 patients receiving long-term cabergoline administration. On multivariate analysis, the absence of cavernous sinus invasion on pretreatment MRI (≥3/4 tumour encasement of the intracavernous internal carotid artery) (HR; 21·94, 95% CI; 2·06-1071·0, P = 0·006), initial PRL <132·7 ng/ml (HR; 8·28, 95% CI; 1·24-199·6, P = 0·03) and nadir PRL <1·9 ng/ml during cabergoline therapy (HR; 5·14, 95% CI; 1·10-39·02, P = 0·04) showed statistically significant correlations with remission after withdrawal. Cabergoline therapy can achieve a high percentage (73% in this series) of remission maintenance for at least 12 months after cessation of a 5-year course of therapy, even in patients with macroprolactinomas. The absence of cavernous sinus invasion, serum PRL level lower than 132·7 ng/ml before cabergoline therapy or nadir serum PRL below 1·9 ng/ml were related to more frequent remission after withdrawal of cabergoline in patients receiving this medication for 5 years.

Posttraumatic Internal Carotid Artery Pseudoaneurysm: Endovascular Management by Stent–Graft Placement

Intracavernous internal carotid artery (ICA) pseudoaneurysms are extremely rare among isolated sphenoid fractures. We report a case of a 28-year-old man who suffered from neurotrauma due to a fall of the ceiling fan over the head and subsequently developed headache with recurrent episodes of profuse epistaxis for the next 10 days. Magnetic resonance angiography revealed a large pseudoaneurysm involving intracavernous ICA. The patient underwent emergent digital subtraction angiography and a covered stent graft was used to reconstruct the ICA. Patient was discharged 5 days later completely asymptomatic and was called up for follow-up after 3 months. This case report highlights the importance of high index of suspicion of vascular injury and emergent endovascular treatment to prevent mortality in base of skull fractures.

Primary Lymphomas of the Skull Base from a Neurosurgical Perspective: Review of the Literature and Personal Experience.

Primary lymphomas of the skull base are exceedingly rare and thus not commonly dealt with in everyday clinical practice. Primary diffuse large B cell lymphoma is the most commonly found (30-40% of primary non-Hodgkin lymphomas of the bone). This article reports a case of primary lymphoma of the skull base and reviews all the relevant literature in the PubMed, National Institutes of Health Library, and Google Scholar databases to outline the clinical, diagnostic, and surgical traits of this yet widely unexplored pathology. The incidence of cases peaks between 60 and 70 years of age; those affected tend to be mostly male. The clinical presentation of this pathology is usually abrupt with headache and acute deficit of cranial nerves that improves dramatically with intravenous corticosteroid therapy. The abducens nerve is most commonly involved. Imaging can be unclear because corticosteroid medications can significantly alter magnetic resonance imaging findings, at least in the early stages of the disease, similarly to what happens for primary brain lymphomas ("the ghost tumor"). Cavernous sinus, parasellar region, upper clivus, and Meckel cave are usually found to be already affected by the time a diagnosis can be made. The intracavernous internal carotid artery is usually encased by the lesion rather than displaced. Because of the anatomical pattern of primary lymphomas of the skull base and their well-known chemosensitivity, surgery is usually only used for diagnosis. Surgical approaches for primary lymphoma of the skull base include transcranial and transnasal-transsphenoidal endoscopy and microsurgery as well as other minimally invasive techniques. Due to the rarity of this neoplasm, there are no definitive data regarding the overall survival rate among patients.

Systematic Analysis of the Risk Factors Affecting the Recurrence of Traumatic Carotid-Cavernous Sinus Fistula

The current therapies for traumatic carotid-cavernous sinus fistula (tCCF) yield a variable rate of recurrence and produce different results. We analyzed factors among traumatic head injury to identify the risk factors in recurrent tCCFs. We retrospectively reviewed patients who were diagnosed with tCCFs from January 2004 to December 2014 in a tertiary referral center. The factors that were analyzed included age, sex, associated injury, clinical presentation, interval from injury to interventions, interventions for tCCFs, and pathologic characters of tCCFs under digital subtraction angiography. A total of 55 patients with 56 tCCFs (1 bilateral tCCF) were included. Thirty-nine patients (40 tCCFs) were treated successfully in single session of a procedure, whereas 16 patients (16 tCCFs) experienced a recurrence of tCCF. In multivariate analysis, we found that the involvement of C2 or C4 segments (Debrun classification) of intracavernous internal carotid artery is an independent risk factor (hazard ratio [HR] 2.95, 95% confidence interval [95% CI] 1.34-6.52; P < 0.01) for the recurrence of tCCFs. Endovascular coil embolization demonstrated superior efficacy in successful interventions of tCCFs compared with detachable balloons (HR 2.63, 95% CI 1.06-6.57; P<0.05) and other modalities (HR 3.06, 95% CI: 1.27-7.37; P< 0.05). A detachable coil is a favorable approach in the management of tCCFs when considering the rate of recurrence. In addition, the involvement of C2 or C4 segments (Debrun classification) served as an independent risk factor of the recurrence of tCCFs.

Curative Reconstruction of Giant Fusiform Intracranial Aneurysms with Flow-Diverter and Self-expanding Stents

To demonstrate the curative reconstruction of two giant fusiform aneurysms using a combination of flow-diverter stents and self-expanding stents for intracranial use. Two cases that would have been difficult to manage with standard methods: one patient with deficiencies of cranial nerves VI and VII on the left, acute diplopia, and an aneurysm of the vertebrobasilar bifurcation, the other with diplopia, deficiencies of cranial nerves III and VI, and an aneurysm of the intracavernous internal carotid artery. INTERVENTION OR TECHNIQUE: Complete reconstruction was achieved using a combination of flow-diverter and self-expandable stents. Follow-up investigations at 6 months demonstrated the complete reconstruction of the arteries and angiographically determined disappearance of the aneurysms with resolution of the clinical profile. The patients' outcome was excellent (modified Rankin Scale: 0). This technique enables safe and definitive treatment of lesions that would be difficult to manage with other methods. The greater metal surface does not seem to interfere with the perforating arteries originating from the segments involved.

Invasion of the cavernous sinus space in pituitary adenomas: endoscopic verification and its correlation with an MRI-based classification.

OBJECT An important prognostic factor for the surgical outcome and recurrence of a pituitary adenoma is its invasiveness into parasellar tissue, particularly into the space of the cavernous sinus (CS). The aims of this study were to reevaluate the existing parasellar classifications using an endoscopic technique and to evaluate the clinical and radiological outcomes associated with each grade. METHODS The authors investigated 137 pituitary macroadenomas classified radiologically at least on one side as Grade 1 or higher (parasellar extension) and correlated the surgical findings using an endoscopic technique, with special reference to the invasiveness of the tumor into the CS. In each case, postoperative MRI was performed to evaluate the gross-total resection (GTR) rate and the rate of endocrinological remission (ER) in functioning adenomas. RESULTS The authors found a 16% rate of CS invasion during surgery for these macroadenomas. Adenomas radiologically classified as Grade 1 were found to be invasive in 1.5%, and the GTR/ER rate was 83%/88%. For Grade 2 adenomas, the rate of invasion was 9.9%, and the GTR/ER rate was 71%/60%. For Grade 3 adenomas, the rate of invasion was 37.9%, and the GTR/ER rate was 75%/33%. When the superior compartment of the CS (Grade 3A) was involved, the authors found a rate of invasion that was lower (p < 0.001) than that when the inferior compartment was involved (Grade 3B). The rate of invasion in Grade 3A adenomas was 26.5% with a GTR/ER rate of 85%/67%, whereas for Grade 3B adenomas, the rate of surgically observed invasion was 70.6% with a GTR/ER rate of 64%/0%. All of the Grade 4 adenomas were invasive, and the GTR/ER rate was 0%. A comparison of microscopic and endoscopic techniques revealed no difference in adenomas with Grade 1 or 4 parasellar extension. In Grade 2 adenomas, however, the CS was found by the endoscopic technique to be invaded in 9.9% and by microscopic evaluation to be invaded in 88% (p < 0.001); in Grade 3 adenomas, the difference was 37.9% versus 86%, respectively (p = 0.002). Grade 4 adenomas had a statistically significant lower rate of GTR than those of all the other grades. In case of ER only, Grade 1 adenomas had a statistically significant higher rate of remission than did Grade 3B and Grade 4 adenomas. CONCLUSIONS The proposed classification proved that with increasing grades, the likelihood of surgically observed invasion rises and the chance of GTR and ER decreases. The direct endoscopic view confirmed the low rate of invasion of Grade 1 adenomas but showed significantly lower rates of invasion in Grade 2 and 3 adenomas than those previously found using the microscopic technique. In cases in which the intracavernous internal carotid artery was encased (Grade 4), all the adenomas were invasive and the GTR/ER rate was 0%/0%. The authors suggest the addition of Grades 3A and 3B to distinguish the strikingly different outcomes of adenomas invading the superior CS compartments and those invading the inferior CS compartments.

海綿静脈洞部大型・巨大内頚動脈瘤に対する頭蓋外内バイパス術とそのピットフォール

Our treatment modalities and techniques for intracavernous large or giant internal carotid artery (ICA) aneurysms have been changed based on past clinical experience. We report clinical results and pitfalls of bypass surgery for intracavernous ICA aneurysms. This study included unruptured symptomatic 37 intracavernous ICA aneurysms in 36 patients. Treatment methods were selected based on the anatomical features of the aneurysm and neurological/hemodynamic conditions during balloon test occlusion (BTO). Eleven aneurysms were treated without bypass surgery. Low flow bypass (STA-MCA anastomosis) was performed for 18 aneurysms, and eight aneurysms were treated with high flow bypass. A saphenous vein graft was originally used for high flow bypass, but it was changed with a radial artery because of the problem of long-term patency. ICA occlusion was accomplished by ligation of the cervical ICA alone in the early cases until we encountered a case with brain infarction due to emboli from the aneurysm after ICA ligation. Accordingly, ICA occlusion was performed by endovascular internal trapping two days after bypass surgery. There was, however, a case of graft thrombosis before ICA occlusion. We now occlude ICA by surgical trapping between the neck and the intracranial ICA immediately after revascularization. No patients had permanent ischemic neurological deficits due to cerebral hypoperfusion after ICA occlusion. Our treatment algorithm based on BTO was reliable. When the patients undergo bypass surgery, we perform ICA occlusion by surgical trapping between the neck and the intracranial portion.

Effective coil embolization of intracavernous carotid artery pseudoaneurysm with parental artery preservation following severe head trauma in a pediatric patient

Intracranial traumatic pseudoaneurysms are rare in children. If left untreated, mortality rate can be as high as 50% due to delayed rupture and disastrous bleeding. Endovascular embolization is considered the preferred treatment option because of its minimal invasiveness and negligible mortality. However, exclusion of the pseudoaneurysm with preservation of the parental vessel is not always possible. In comparison with peripheral aneurysms, intracavernous internal carotid artery lesions are technically more challenging with both open surgery and endovascular techniques. We report the case of a successful two-stage coil embolization of a traumatic intracavernous carotid artery pseudoaneurysm with preservation of parental vessel in a 6-year-old boy. Endovascular embolization with parental vessel preservation should be considered the first treatment option for traumatic intracavernous internal carotid artery pseudoaneurysms in children. Although treatment of pseudoaneurysms in this location may be technically difficult, it is feasible in experienced hands.