Carotid Artery-Cavernous Segment Injury during an Endoscopic Endonasal Surgery: A Case Report and Literature Review of the Overlooked Option for Surgical Trapping in the Hyperacute Phase.

Internal carotid artery (ICA) injury is a catastrophic complication of endoscopic endonasal surgery (EES). However, its standard management, emergent endovascular treatment, may not always be available, and the transnasal approach may be insufficient to achieve hemostasis. A 44-year-old woman with pituitary adenoma underwent EES complicated with the ICA cavernous segment injury (CSI). In urgent intraoperative angiogram, a good collateral flow from the contralateral carotid circulation was observed. Due to the unavailability of intraoperative embolization, emergent surgical trapping was performed by combined transcranial and cervical approach. The patient recovered but later developed a giant cavernous pseudoaneurysm. During the pseudoaneurysm embolization, ICA was directly accessed via a 1.7-F puncture hole using a bare microcatheter technique. Then, both the aneurysm and parent artery were obliterated with coils. At the 4-year follow-up, the patient was asymptomatic without a residual tumor. To our knowledge, this is the first case of ICA-CSI during EES successfully treated with ICA trapping as a lifesaving urgent surgery that achieved a complete recovery after a pseudoaneurysm embolization. Although several studies reported that EES-related ICA-CSIs with percutaneous carotid artery access, neither our surgical salvage technique nor our carotid access and tract embolization techniques were previously described.

Aberrant course of the precavernous-cavernous junction of the internal carotid artery.

We present an extremely rare case of an aberrant course of the precavernous-cavernous junction of the internal carotid artery (ICA), which was observed by magnetic resonance (MR) angiography. The patient was a 67-year-old woman with no symptoms related to the anomalous ICA. The anomalous segment of the ICA was stenotic and formed a loop postero-supero-laterally. We found no similar cases in the relevant English-language literature. Segmental agenesis of the ICA with collateral formation, probably via the proximal segment of the primitive trigeminal artery, may be associated with the development of this variation.

Cavernous carotid artery large aneurysm treated with a new flow diverter - Xcalibur aneurysm occlusion device (AOD).

We report a case of an unruptured, symptomatic, large right cavernous internal carotid artery aneurysm successfully treated with a new balloon-expandable flow diverter - Xcalibur Aneurysm Occlusion Device (AOD). Follow up imaging performed at six months demonstrated complete exclusion of the aneurysm and regression in dimensions, resulting in resolution of mass effect and clinical improvement.

Flow-Diverter Stenting of Intracavernous Internal Carotid Artery Mycotic Aneurysm.

This is the first reported case in which a mycotic aneurysm refractory to the first medical treatment was treated with a Pipeline embolization device (PED), and the first case of a mycotic aneurysm from Brucella treated by endovascular therapy. A 35-year-old man presented with left eye pain and ptosis, and fever for 2 weeks. Before symptom onset, he visited Vietnam where he developed a flu-like illness; however, antibiotics were ineffective. We suspected Brucella as the most likely infectious etiology for the patient's intracavernous aneurysm. Since the aneurysm did not reduce in size following 2 weeks of antibiotic therapy, we placed a PED in the left internal carotid artery. Follow-up angiogram 4 months later showed no residual aneurysm, and cranial nerve palsies had completely resolved. From the results of this case, it appears that flow diverter stenting may be a safe and effective treatment of mycotic aneurysms of the cavernous segment of ICA.

Massive Epistaxis from Nontraumatic Cavernous Carotid Aneurysm Treated by High-Flow Bypass and Cervical Internal Carotid Artery Ligation: A Case Report and Review of the Literature.

BACKGROUND: Epistaxis is a rare presentation of the ruptured cavernous carotid aneurysm, especially the nontraumatic type. Both endovascular therapies and open surgeries have a role in the treatment with various outcomes, but the standard procedure is not well established. We report a successful high-flow bypass with cervical internal carotid artery ligation for aneurysm repair and review the related literature. CASE DESCRIPTION: An 81-year-old man presented with massive epistaxis from the left nostril. The epistaxis was controlled by nasal packing. A saccular aneurysm of the cavernous segment of the left internal carotid artery projecting into the sphenoid sinus was revealed using computed tomography angiography. We treated this patient with high-flow bypass with ligation of the cervical internal carotid artery. Immediate postoperative computed tomography angiography showed complete disappearance of the aneurysm. Nasal packing was removed without further bleeding. No neurological deficit or complications were detected in the postoperative period. CONCLUSIONS: In cases of massive or recurrent epistaxis without coagulopathy or nasal pathology, a cavernous carotid aneurysm should be considered. Immediate cessation of the bleeding is necessary. Flow-preservation bypass with proximal ligation of the parent artery is 1 of the effective procedures for the treatment of this condition with low morbidity.

Atypical Manifestation of Direct Low-Flow Carotid-Cavernous Fistula: Case Report and Review of the Literature.

BACKGROUND: Carotid cavernous fistula (CCF) is a rare type of arteriovenous shunt that develops within the cavernous sinus (CS). Direct CCFs entail a direct communication between the cavernous internal carotid artery and the CS and are typically high-flow lesions. Most CCFs drain into the ophthalmic veins (typical venous drainage pattern), leading to the pathognomic ocular clinical triad associated with a CCF. When an obstruction of the typical venous outflow is present, the arterial pressure generated by the fistula is transmitted into the cerebral venous system via the sphenoparietal sinus, which might lead to intracerebral hemorrhage. We present a rare case of posttraumatic, direct, low-flow CCF associated with cerebral hemorrhage, a typical venous drainage pattern, and without ocular symptoms at presentation. CASE DESCRIPTION: A 76-year-old woman was hospitalized for a posttraumatic frontotemporopolar hemorrhage associated with multiple fractures of the maxillofacial and cranial base skeleton and midline shift >10 mm. On neurologic examination the Glasgow Coma Scale was 8 and right anisocoria was present. Immediate surgical evacuation of the hematoma was performed. Severe arterial bleeding from the anterior third of the middle cranial fossa floor was controlled intraoperatively. Postoperative brain angio-magnetic resonance imaging and digital subtraction angiography showed a direct CCF without theft phenomenon. Ocular symptoms, and ultimately loss of function of the right eye, appeared 2 weeks from surgery. Endovascular treatment of the CCF was attempted attaining partial closure of the shunt using coils. CONCLUSIONS: Direct low-flow CCFs are exceedingly rare lesions. Five cases have been described in the literature, 4 of which were associated with spontaneous rupture of a cavernous carotid aneurysm while only 1 case was associated with posttraumatic rupture of a cavernous internal carotid artery pseudoaneurysm. In addition, despite our patient having developed an intraparenchymal hemorrhage most probably correlated to the CCF, the latter was associated with a typical venous drainage via the superior ophthalmic vein, which is uncommonly correlated to intraparenchymal bleeding.

Cavernous sinus aneurysms: risk of growth over time and risk factors.

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

Preoperative assessment of the risk of cavernous ICA injury in endoscopic transsphenoidal surgery.

In endoscopic endonasal transsphenoidal procedures, ICA injury occurs in up to 3.8% [1]. The highest hazard of injury is in case of contact between the ICA and pituitary gland, during opening of the dura. Preoperative imaging, i.e. CTA, MRA, supports objectively intraoperative techniques of imaging. CTA as well as MRA are essential to access anatomic details in variability of cavernous segments of the ICA (C4 ICA). The aim of the study was to measure the space between Internal Carotid Arteries and distances between the pituitary gland and ICA on both sides. Anatomic relations between left and right ICAs were accessed on CTA (coronal scans) at levels: A - The most concave point of the C4-C5 bend; B - The most convex point of the C4 bend; C - The C4 posterior ascending portion. Distances between pituitary gland and ICAs were measured on both sides on MRA (axial scans): A' - The most concave point of C4-C5 bend; B' - The most convex point of the C4 bend. The Statistica 13 (StatSoft) software was used for the statistical analysis. The Mann-Whitney U test was applied to determine differences between the groups. To analyze the strength of correlations between the quantitative variables, Spearman's rank correlation coefficients were calculated. The results were considered statistically significant at the level of P < 0.05. Distance reduction was shown between pituitary glands and cavernous segment (C4) of ICAs on both sides, which is related to age. This has impact on surgical planning and highlights the risk of intraoperative injury of ICAs.

Endoscopic Endonasal Clipping of Anterior Circulation Aneurysm: Surgical Techniques and Results.

BACKGROUND: Endoscopic endonasal clipping of intracranial aneurysms may use microsurgical techniques as an alternative to the transcranial approach. Here we report a series of patients who underwent microsurgical clipping of anterior circulation aneurysms via an endoscopic endonasal approach (EEA). METHODS: This retrospective chart review included all the patients who underwent standard binostril EEA for aneurysm clipping. Surgical outcomes and complications are noted. The rationality and limitations of this procedure are discussed. RESULTS: Seven patients with 12 aneurysms of the anterior circulation underwent EEA for clipping. These 12 aneurysms consisted of 5 anterior communicating artery (AComA) aneurysms, 4 paraclinoid aneurysms, 1 ophthalmic artery aneurysm, and 2 aneurysm located in the cavernous segment of internal carotid artery (ICA). Nine of the 12 aneurysms were successfully clipped. One giant paraclinoid aneurysm could not be clipped during operation and was coiled in second endovascular stage. The 2 aneurysms located in the cavernous segment of ICA were not clipped intentionally in a single-stage procedure, after weighing the surgical benefit against the difficulty of surgical exposure and feasibility. The proximal control of ICA was achieved in all cases. There was no death, no cerebrospinal fluid leak, or other complications. All patients recovered completely. CONCLUSIONS: EEA can provide direct access for microsurgical clipping of strictly selected anterior circulation aneurysms. All the principles of cerebrovascular surgery must be followed. These procedures require a long learning curve. Only teams with adequate experience in microvascular and endoscopic skull base surgeries should attempt this approach for treating aneurysms.

Anatomical study of petrous and cavernous parts of internal carotid artery.

The petrous and cavernous parts of internal carotid artery (ICA) are obscure and are not readily accessible to observation/imaging. These parts have broad biological and medical interest because of their peculiar shape. Given the their clinical importance and the scarce data available based mostly on imaging, the present study was aimed at studying these parts of ICA by dissection. The study was carried out on 56 ICAs obtained from embalmed adult cadavers and 10 ICAs from five fetuses. The foetal ICAs were studied in situ. The morphometric analysis of the adult ICA was done after its removal from cranial cavity to gain an insight into the geometry of the vessel, i.e., length, various bends, and diameters at various locations. ICAs in fetuses ran a relatively straighter course taking gentle curves at three positions (two intrapetrous, one cavernous). Adult ICAs were more tortuous and exhibited greater variability in length and angulations. The length of respective portions of the ICA correlate negatively with the measure of angles. The angles in the petrous and cavernous parts were positively correlated to each other. The carotid siphon was positively, highly significantly correlated to other angles. Longer vessels are more tortuous with acute bends. An acute carotid siphon is an indication of more tortuous ICA. The findings of the present study have created a reference data of unsuspected adult population and has potential implications for studying cause/effect relationship of vessel geometry and hemodynamic factors.

Fourth cranial nerve: surgical anatomy in the subtemporal transtentorial approach and in the pretemporal combined inter-intradural approach through the fronto-temporo-orbito-zygomatic craniotomy. A cadaveric study.

Despite the recent progress in surgical technology in the last decades, the surgical treatment of skull base lesions still remains a challenge. The purpose of this study was to assess the anatomy of the tentorial and cavernous segment of the fourth cranial nerve as it appears in two different surgical approaches to the skull base: subtemporal transtentorial approach and pretemporal fronto-orbito-zygomatic approach. Four human cadaveric fixed heads were used for the dissection. Using both sides of each cadaveric head, we made 16 dissections: 8 with subtemporal transtentorial technique and 8 with pretemporal fronto-orbito-zygomatic approach. The first segment that extends from the initial point of contact of the fourth cranial nerve with the tentorium (point Q) to its point of entry into its dural channel (point D) presents an average length of 13.5 mm with an extremely wide range and varying between 3.20 and 9.3 mm. The segment 2, which extends from point D to the point of entry into the lateral wall of the cavernous sinus, presents a lesser interindividual variability (mean 10.4 mm, range 15.1-5.9 mm). A precise knowledge of the surgical anatomy of the fourth cranial nerve and its neurovascular relationships is essential to safely approach. The recognition of some anatomical landmarks allows to treat pathologies located in regions of difficult surgical access even when there is an important subversion of the anatomy.

Comparison of the effectiveness of using the optic strut and tuberculum sellae as radiological landmarks in diagnosing paraclinoid aneurysms with CT angiography.

OBJECTIVE The treatment of paraclinoid aneurysms remains challenging. It is important to determine the exact location of the paraclinoid aneurysm when considering treatment options. The authors herein evaluated the effectiveness of using the optic strut (OS) and tuberculum sellae (TS) as radiographic landmarks for distinguishing between intradural and extradural paraclinoid aneurysms on source images from CT angiography (CTA). METHODS Between January 2010 and September 2013, a total of 49 surgical patients with the preoperative diagnoses of paraclinoid aneurysm and 1 symptomatic cavernous-clinoid aneurysm were retrospectively identified. With the source images from CTA, the OS and the TS were used as landmarks to predict the location of the paraclinoid aneurysm and its relation to the distal dural ring (DDR). The operative findings were examined to confirm the definitive location of the paraclinoid aneurysm. Statistical analysis was performed to determine the diagnostic effectiveness of the landmarks. RESULTS Nineteen patients without preoperative CTA were excluded. The remaining 30 patients comprised the current study. The intraoperative findings confirmed 12 intradural, 12 transitional, and 6 extradural paraclinoid aneurysms, the diagnoses of which were significantly related to the type of aneurysm (p < 0.05) but not factors like sex, age, laterality of aneurysm, or relation of the aneurysm to the ophthalmic artery on digital subtraction angiography. To measure agreement with the correct diagnosis, the OS as a reference point was far superior to the TS (Cohen's kappa coefficients 0.462 and 0.138 for the OS and the TS, respectively). For paraclinoid aneurysms of the medial or posterior type, using the base of the OS as a reference point tended to overestimate intradural paraclinoid aneurysms. The receiver operating characteristic curve indicated that if the aneurysmal neck traverses the axial plane 2 mm above the base of the OS, the aneurysm is most likely to grow across the DDR and present as a transitional aneurysm (sensitivity 0.806; specificity 0.792). CONCLUSIONS High-resolution thin-cut CTA is a fast and crucial tool for diagnosing paraclinoid aneurysms. The OS serves as an effective landmark in CTA source images for distinguishing between intradural and extradural paraclinoid aneurysms. The DDR is supposed to be located 2 mm above the base of the OS in axial planes.

Diffusion-weighted imaging-detected ischemic lesions associated with flow-diverting stents in intracranial aneurysms: safety, potential mechanisms, clinical outcome, and concerns.

OBJECT: It was initially considered safe for flow-diverting stents to cover the ostia of branching vessels during endovascular procedures for the treatment of intracranial aneurysms. As more recent evidence suggests, however, their use is not always free of ischemic concerns in terms of covered arterial ostia. The authors sought to determine the frequency of silent and clinically evident diffusion-weighted imaging (DWI)-detected abnormalities related to stent placement as a means of elucidating potential clinical risks. METHODS: This is a prospective single-center study on a series of patients with intracranial aneurysms that were treated with flow-diverting stents. All patients systematically underwent an MRI protocol that included DWI before treatment, between 24 and 48 hours postprocedure, and 3 months postembolization. Effectiveness of anticoagulation treatment was assessed for all patients. Lesions seen on DWI were correlated to the parent artery and the side-branch territories and were statistically analyzed in relation to their time of occurrence and clinical presentation. The authors compared the DWI findings in these patients to findings obtained in patients treated with a stent-assisted coiling technique during the same time period. RESULTS: Over the course of 18 consecutive months, 38 consecutive patients (7 males and 31 females) with 49 intracranial aneurysms were treated using flow-diverting stents. Overall, 81.6% of the DWI spots found remained clinically silent during the follow-up period. Five ischemic clinical complications (13.2%) occurred in the postprocedural period. No statistically significant correlation could be established between DWI spots or aneurysm location and clinical complications or follow-up modified Rankin Scale score at 3 months. The complication rate was 7.8% (n = 3) at the 3-month follow-up, and mortality was 0%. Compared with stent-assisted coiling, use of flow-diverting stents showed a statistically significant correlation with silent DWI findings postintervention. CONCLUSIONS: Lesions seen on DWI resulting from the procedure are far more common than anticipated, but the technique remains safe and effective, providing an interesting alternative for "difficult" aneurysms, regardless of location. Late-occurring DWI-detected lesions distal to side arterial branches imply a local pressure gradient drop, related to flow competition by collateral networks. Further research is needed to assess the extent and significance of these events.