Internal carotid artery injury during endoscopic transsphenoidal pituitary surgery: risk factors, management.

BACKGROUND: Transsphenoidal surgeons should try to avoid internal carotid artery (ICA) injury but also be prepared to manage it. We analyzed our experience with ICA injury during endoscopic transsphenoidal pituitary surgery and present associated risk factors and a management protocol. METHODS: We retrospectively reviewed and analyzed the medical records of 1596 patients who underwent endoscopic transsphenoidal surgery for pituitary tumor resection in our institution from January 2009 to October 2022. RESULTS: Six patients experienced an ICA injury. All received timely and effective hemostasis with immediate direct tamponade followed by endovascular treatment. No serious postoperative complications occurred. CONCLUSIONS: We proposed a treatment plan for ICA injuries encountered during endoscopic transsphenoidal surgery and described our hemostasis process, methods of endovascular treatment, and means of postoperative follow-up in detail.

Strategies to avoid internal carotid artery injury in "sandwich" atlantoaxial dislocation patients during surgery.

PURPOSE: To elucidate the anatomic relationship between the internal carotid artery (ICA) and the bony structures of the craniovertebral junction among "sandwich" atlantoaxial dislocation (AAD) patients, and to analyze the risks of injury during surgical procedures. METHODS: The distance from the medial wall of ICA to the midsagittal plane (D1), the shortest distance between the ICA wall and the anterior cortex of the lateral mass of atlas (LMA) (D2) on the most caudal and cranial levels of LMA and the angle (A) between the sagittal plane passing through the screw entry point of C1 lateral mass(C1LM) screw and the medial tangent line of the vessel passing through the entry point were measured. Besides, the location of ICA in front of the atlantoaxial vertebra was divided into 4 categories (Z1-Z4). RESULTS: There was a statistically difference between the male and female patients regarding D1, and the difference between D2 at level a and level b as well as angle A between the left and right sides were statistically different (p < 0.05). Ninety-two ICAs (57.5%) were anteriorly located in Z3, 50 (31.3%) were located in Z4, 17 were located in Z2, and only one ICA was located in Z1 in all 80 patients. CONCLUSIONS: In "sandwich" AAD patients, particular attention should be paid to excessively medialized ICA to avoid ICA injury during trans-oral procedures, and the risk of injuring the ICA with more cranially and medially angulated C1LM screw placement was relatively less during posterior fixation procedures. A novel classification of ICA location was used to describe the relationship between ICA and LMA.

Interracial anatomical differences in the transsphenoidal approach to the sellar region.

OBJECTIVE: Injury to vascular structures such as the internal carotid artery (ICA) is a rare but catastrophic complication of minimally invasive transsphenoidal surgery. Thorough preoperative planning, and knowledge of anatomical landmarks, such as the intercarotid distance (ICD) reduce this risk. Numerous anatomical studies have been conducted regarding the transsphenoidal approach, but none have taken racial disparities into account. METHODS: Since differences of the cranium, especially of the skull base exist, we sought to analyze anatomical differences of the sellar region in thin sliced T2-weighted MRI scans of 187 (87 male and 100 female) Asian, African American and Caucasian patients provided by the 'Human Connectome Project' (HCP). RESULTS: We found significant differences in the ICD between males and females across all races. Furthermore, we found that the ICD was up to 2.4 mm smaller in the Caucasian cohort compared to the African American/Asian cohort. CONCLUSION: These findings indicate that racial disparities regarding the sellar anatomy should be considered in patients undergoing pituitary surgery.

Vascular injury arising from lateral skull base fractures.

PURPOSE: Although uncommon, vascular injury can be seen in patients with lateral skull base fractures (LSBF). However, little is known about this potentially life-threatening comorbidity. The objective of this study is to better characterize the vascular injuries associated with temporal and lateral sphenoid bone fractures. BASIC PROCEDURES: Retrospective review of all patients with computed tomography angiography (CTA) performed specifically to evaluate for vascular injury following LSBF. In addition to patient demographics (age, gender, race), the mechanism of injury, the location of fracture(s), and the nature of vascular injury diagnosed by CTA was recorded. Two-way ANOVA was performed to determine if any variables were predictive of vascular injury. MAIN FINDINGS: From 2011 to 2021, 143 patients with 333 subsite fractures met inclusion criteria. Of all patients, 46 (32.2 %) had CTA evidence of at least one vascular injury, the most common type being venous thrombosis/filling defect (41.7 %). Evidence of vascular injury was unclear in 14 patients (9.8 %). Fractures most associated with vascular injury ranged from 0.7 % (otic capsule fractures) to 26.7 % (mastoid, lateral sphenoid fractures). Risk of vascular injury was no different between patients with single vs multiple fractures. There were no fracture locations that could reliably predict specific vascular injury. CONCLUSIONS: Over 40 % of all CTAs ordered following LSBF identified were suspicious for associated vascular injury. Yet fracture location and number cannot reliably predict vascular injury. Until such determinants can be better identified, clinicians should have a low threshold to obtain CTA to rule out associated vascular injury.

A Cost-Effective and Reproducible Cadaveric Training Model for Internal Carotid Artery Injury Management During Endoscopic Endonasal Surgery: The Submersible Peristaltic Pump.

BACKGROUND: Internal carotid artery injury (ICAI) represents one of the most challenging complications in endoscopic endonasal neurosurgery and its rarity results in limited opportunities for trainees and surgeons to achieve proficiency in its management. Currently, available models for ICAI have employed costly systems that prevent their widespread use. The objective of this study is to validate an affordable submersible peristaltic pump (SPP)-based model as a reproducible and realistic paradigm for ICAI management training. METHODS: A laceration of the left parasellar internal carotid artery was purposely carried out in 2 human cadaveric heads. A blood substitute was perfused to ensure a perfusion flow of 1 L/min using an affordable SPP. A cohort of 20 neurosurgery and otolaryngology residents, fellows, and attendings were enrolled to evaluate the realism and content validity of the model using a validated 5-grade questionnaire. RESULTS: The model proved to mimic a real intraoperative scenario of ICAI with an expected output flow of 1 L/min. Questionnaire responses reported a realistic experience and the impact of this model on improving trainee surgical coordination and capability to rehearse the most accepted repair technique. The use of a fixed noninjected head allowed the reproducibility of the training session without the additional cost of new fresh-frozen heads. The affordable SPP allowed an impactful reduction of ICAI model training expenses maintaining high realism. CONCLUSIONS: The SPP-based ICAI model with noninjected cadaveric specimens is an affordable and cost-effective system that allows reproducibility and realism. These qualities favor greater adoption in neurosurgery and otolaryngology training curricula.

Which Patients Receive Diagnostic Angiography? An EAST Multicenter Study Analysis of Internal Carotid Artery Blunt Cerebrovascular Injury.

BACKGROUND: Digital subtraction angiography (DSA) is the gold standard radiologic modality in blunt cerebrovascular injury (BCVI). However, computerized tomography angiography (CTA) is primarily used in modern practice with CTA's widespread availability and the decreased stroke rate with CTA use. The frequency and indications for DSA in BCVI is undefined. We hypothesized that DSA use in internal carotid artery (ICA) BCVI would be infrequent and dependent on radiologic features. METHODS: This was a post hoc analysis of an EAST multicenter, prospective, observational trial of 16 trauma centers for stroke factors in BCVI. ICA BCVI was divided into those undergoing DSA and not undergoing DSA (no-DSA). Only ICA BCVI was included. RESULTS: 332 ICA BCVI were included, 221 (66.6%) no-DSA and 111 (33.4%) DSA. Lower hospital trauma volume, non-urban environment, and non-academic status were associated with DSA use (all P ≤ .001). BCVI grade (P = .02) and presence of luminal stenosis (P = .005) were associated with DSA use while pseudoaneurysm presence was not. Median time to DSA was 1 hour. The most common indication for angiography was to determine the presence of injury in 71 (64%) ICA BCVI, followed by determining grade of injury in 16 (14.4%) and concerning imaging characteristics in 12 (10.8%). BCVI grade on initial imaging and on DSA were equivalent in 94 (84.7%) ICA BCVI. DISCUSSION: DSA is frequently used in ICA BCVI, primarily early in the hospital course for injury diagnosis and grade determination. DSA appears primarily driven by hospital type, BCVI grade, and luminal stenosis.

Emergency treatment and anesthesia management of internal carotid artery injury during neurosurgery: Four case reports.

BACKGROUND: During skull base surgery, intraoperative internal carotid artery (ICA) injury is a catastrophic complication that can lead to fatal blood loss or secondary cerebral ischemia. Appropriate management of ICA injury plays a crucial role in the prognosis of patients. Neurosurgeons have reported multiple techniques and management strategies; however, the literature on managing this complication from the anesthesiologist's perspective is limited, especially in the aspect of circulation management and airway management when patients need transit for further endovascular treatment. CASE SUMMARY: We describe 4 cases of ICA injury during neurosurgery; there were 3 cases of pathologically proven pituitary adenoma and 1 case of cavernous sinus endothelial meningioma. After the onset of ICA injury, all four patients were immediately transferred for endovascular therapy under general anesthesia with vital signs monitored and mechanical ventilation. Three patients were transferred to the hybrid operating room, and one patient was transferred to the catheter operating room. Three patients underwent covered stent implantation, and one patient underwent embolization. All four patients experienced hypovolemic shock and received blood products infusion and vasoactive drugs to maintain stable circulation. After the neurosurgery, one patient was extubated and returned to the ward, and the other three were delayed tracheal extubation and returned to the intensive care unit. One patient died from serious neurological complications after 62 d in the hospital, but the other three showed good clinical outcomes. CONCLUSION: ICA injury imposes a high risk of massive hemorrhage and subsequent infarction. Immediate treatment is critical and requires interdisciplinary collaboration among neurosurgeons, anesthesiologists, and interventional neuroradiologists. Effective hemostatic methods, stable hemodynamics sufficient to ensure perfusion of vital organs, airway safety during transit, rapid localization and implementation of appropriate measures to occlude the damaged vessel are strong guarantees of patient safety.

Internal Carotid Injury during Skull Base Surgery-Case Report and a Review of the Literature.

Iatrogenic injury of the internal carotid artery (ICA) is a rare, and probably underreported, complication of transnasal endoscopic skull base surgery. Although treatment algorithms have been suggested, there is no definite consensus or guideline for the management of this severe complication. We describe a case of ICA injury that occurred during a transsphenoidal biopsy of a tumor in the cavernous sinus and we present a treatment algorithm for managing this complication. We reviewed the articles published from 1998 to 2021, reporting on major vascular injury during transnasal endoscopic skull base surgery and endonasal endoscopic surgery, and we compare the methods and results of ICA injury management reported in the literature with the presented case. The most promising treatment for ICA injury might be packing with a muscle graft initially, then performing an endovascular intervention.

Embolization after internal carotid artery injury secondary to transsphenoidal pituitary surgery and delayed intranasal coil protrusion: illustrative case.

BACKGROUND: The authors presented a case of spontaneous nasopharyngeal coil migration that occurred 3 years after a patient had undergone transsphenoidal resection due to pituitary macroadenoma and was treated with coil application because of internal carotid artery injury secondary to transsphenoidal resection of the pituitary macroadenoma. OBSERVATIONS: In the literature, eight cases of coil migration that occurred between 2 and 120 months after coil application have been reported, most of which were treated with surgical removal of the coil in a same-day surgery setting. LESSONS: The case presented emphasized that coil protrusion and migration may lead to destruction in the skull base, thereby leading to serious consequences if left untreated, even in the absence of history of trauma. To the authors' knowledge, this is the first case in the literature that required additional invasive procedures due to recurrent bleeding that occurred several months after surgical removal of coils. Also, this report underlined the need for careful and long-term follow-up of coil materials used for the treatment of pseudoaneurysms caused by vascular injuries secondary to skull base injury during surgery.

Injury to the Extrasellar Portion of the Internal Carotid Artery during Endoscopic Transsphenoidal Surgery: A Case Report.

Background: Injury to the internal carotid artery (ICA) during endoscopic transsphenoidal surgery (ETSS) is a serious complication with a risk of mortality. ICA injury during ETSS usually occurs during intrasellar manipulations and rarely occurs in the extrasellar portion. Several hemostatic procedures have been proposed for ICA injury in the intrasellar portion, whereas hemostatic methods for ICA injury in the extrasellar portion, where the ICA is surrounded by bone structures, are less well known. Case Presentation: A 65-year-old man with an incidental pituitary tumor underwent ETSS. The petrous portion of the left ICA was injured during resection of the sphenoid septum connected with left carotid prominence using a cutting forceps. Bleeding was too heavy for simple hemostatic techniques. Hemostasis using a crushed muscle patch was tried unsuccessfully during controlling of the bleeding. Eventually, the injured site of the ICA was covered with cotton patties followed by closing with a vascularized pedicled nasoseptal flap. Cerebral angiography immediately after surgery showed no extravasation from the injured site of the left ICA petrous portion. However, a carotid-cavernous sinus fistula originating from the injured ICA site was detected 7 days after surgery, so the vascular reconstructive surgery combined with left ICA occlusion was performed. The overall postoperative course was uneventful. Conclusion: We believe that emergency application of the cottonoids may be effective for hemostasis against ICA injury in the extrasellar portion during ETSS, but further vascular reconstruction combined with ICA occlusion on the injured side and removal of the cottonoids would be required.

Emergency extra-intracranial bypass surgery in a patient with neurologic deficit after an accident in carotid occlusive test: A case report.

OBJECTIVE: BTO is the procedure performed to assess the collateral circulation within the Willis circle in a giant ICA aneurysm. An ICA occlusion after BTO is very rare. We present a case of an internal carotid artery occlusion as a complication of BTO that required urgent revascularization surgery. CASE PRESENTATION: A 56-year-old female with a history of transient ischemic attacks for one year was diagnosed with multiple aneurysms: a giant aneurysm of the left supra-clinoid ICA, two small ones on left MCA and right ophthalmic. A BTO was performed to assess collateral supply and determine whether bypass surgery should be necessary. During the procedure, the balloon was detached while insufflating, and the patient had a subsequent neurological decline consistent with an MCA syndrome. EC-IC bypass surgery was performed with an end-to-side anastomosis of STA-MCA by trapping the giant aneurysm and clipping the ipsilateral MCA aneurysm. The patient had a reversal of neurological symptoms and made an uneventful recovery. DISCUSSION: We discuss the epidemiology of giant ICA aneurysms, the indications for BTO, and its complication. Emergency intracranial and extracranial bypass surgery in case of acute ICA injury is also discussed. We also highlighted the attributable factors to treatment strategies under restrictive conditions in Vietnam. CONCLUSIONS: ICA occlusion due to insufflated balloon detachment is an unreported complication in literature. Emergency bypass surgery is a potential treatment choice for this unusual iatrogenic complication.

Endovascular Intervention in Internal Carotid Artery Blunt Cerebrovascular Injury: An EAST Multicenter Study.

BACKGROUND: Use of endovascular intervention (EI) for blunt cerebrovascular injury (BCVI) is without consensus guidelines. Rates of EI use and radiographic characteristics of BCVI undergoing EI nationally are unknown. METHODS: A post-hoc analysis of a prospective, observational study at 16 U.S. trauma centers from 2018 to 2020 was conducted. Internal carotid artery (ICA) BCVI was included. The primary outcome was EI use. Multivariable logistic regression was performed for predictors of EI use. RESULTS: From 332 ICA BCVI included, 21 (6.3%) underwent EI. 0/145 (0%) grade 1, 8/101 (7.9%) grade 2, 12/51 (23.5%) grade 3, and 1/20 (5.0%) grade 4 ICA BCVI underwent EI. Stroke occurred in 6/21 (28.6%) ICA BCVI undergoing EI and in 33/311 (10.6%) not undergoing EI (P = .03), with all strokes with EI use occurring prior to or at the same time as EI. Percentage of luminal stenosis (37.75 vs 20.29%, P = .01) and median pseudoaneurysm size (9.00 mm vs 3.00 mm, P = .01) were greater in ICA BCVI undergoing EI. On logistic regression, only pseudoaneurysm size was associated with EI (odds ratio 1.205, 95% CI 1.035-1.404, P = .02). Of the 8 grade 2 ICA BCVI undergoing EI, 3/8 were grade 2 and 5/8 were grade 3 prior to EI. Of the 12 grade 3 ICA BCVI undergoing EI, 11/12 were grade 3 and 1/12 was a grade 2 ICA BCVI prior to EI. DISCUSSION: Pseudoaneurysm size is associated with use of EI for ICA BCVI. Stroke is more common in ICA BCVI with EI but did not occur after EI use.

A novel technique to manage internal carotid artery injury in endoscopic endonasal skull base surgery in the premise of proximal and distal controls.

Intraoperative internal carotid artery injury is one of the most daunting complications in endoscopic skull base surgery. This paper proposed a novel technique to manage ICA injury after proximal and distal controls. The appropriate block sites together with the proximal and distal controls of ICA were demonstrated in six injected cadaveric specimens. The surgical outcomes of five patients with intraoperative ICA injury and managed with this concept were retrospectively reviewed. Five block sites for vascular control could be identified in all six specimens, including (1) distal to the distal dural ring, (2) proximal to the proximal dural ring, (3) anterior genu of the parasellar ICA, (4) the upper third of the paraclival ICA, and (5) just above the foramen lacerum. Both proximal and distal controls of ICA were achieved by using the block sites in combination. Gross tumor resection was achieved in all five cases after the intraoperative ICA injury was successfully managed. Three coping techniques were used, including direct coagulation to seal (three cases), endoscopic suture (one case), and coagulation to sacrifice (one case). Focal brainstem infarction occurred in one case, one patient died of intracranial infection, and the other three cases had no sequelae. No pseudoaneurysm occurred in all patients. Except the sacrificed ICA, the other ICA was intact during follow-up. It is technically feasible to manage ICA injuries after proximal and distal controls during EEA surgeries. The surgical outcomes from our case series supported the use of this novel technique.

Early Experience of Endoscopic Endonasal Transphenoidal Surgery for Pituitary Adenoma: Preliminary Report of 56 Cases Operated in a West African Institution.

BACKGROUND: Although endoscopic endonasal approach (EEA) has been popularized worldwide for pituitary adenoma surgery, in sub-Saharan Africa, neurosurgeons are still only starting their experience with it. This study was designed to assess the early results of EEA for pituitary adenoma from an under-equipped environment, namely, the Department of Neurosurgery of the Teaching Hospital of Yopougon Abidjan and Bouaké in Ivory Coast. METHODS: The data of 56 cases of EEA for pituitary adenoma surgery performed between 2016 and March 2019 at the Teaching Hospital of Yopougon-Abidjan and Bouaké were retrospectively assessed. Pre- and postoperative neuro-ophthalmologic and hormonal status were analyzed. Moreover, the quality of tumor removal, and pre- and postoperative complications were also evaluated. RESULTS: In this study, there were nonfunctional adenomas (20), prolactinoma (18), Cushing disease (9), and acromegaly (3). A reduced visual acuity and/or visual field defect was observed in 49 cases. The mean operation time was 225 ± 94.7 minutes. The tumor removals were complete in 57.14%, subtotal in 35.71%, and partial in 7.14%. These led to a visual improvement in 69.64%. Postoperative complications were cerebrospinal fluid leaks (19.64%), diabetes insipidus (12.50%), visual worsening (7.14%), meningitis (3.57%), and carotid injury (3.57%) that led to death. CONCLUSIONS: This study represents the early surgical experience using EEA for treating pituitary adenoma in an under-equipped environment. Although the postoperative complication rate was relatively high, refinements of local surgeons' technique would lead to a better patient outcome.

Internal Carotid Artery Injury in Transsphenoidal Surgery: Tenets for Its Avoidance and Refit-A Clinical Study.

One of the most serious/potentially fatal complications of transsphenoidal surgery (TSS) is internal carotid artery (ICA) injury. Of 6230 patients who underwent TSS, ICA injury occurred in 8 (0.12%). The etiology, possible treatment options, and avoidance of ICA injury were analyzed. ICA injury occurred at two different stages: (1) during the exposure of the sella floor and dural incision over the sella and cavernous sinus and (2) during the resection of the cavernous sinus extension of the tumor. The angiographic collateral blood supply was categorized as good, sufficient, and nonsufficient to help with the decision making for repairing the injury. ICA occlusion with a balloon was performed at the injury site in two cases, microcoils in two patients, microcoils plus a single barrel extra-intracranial high-flow bypass in one case, stent grafting in one case, and no intervention in two cases. The risk of ICA injury diminishes with better preoperative preparation, intraoperative navigation, and ultrasound dopplerography. Reconstructive surgery for closing the defect and restoring the blood flow to the artery should be assessed depending on the site of the injury and the anatomical features of the ICA.

Repair of internal carotid artery injury with aneurysm clip during endoscopic endonasal surgery: illustrative case.

BACKGROUND: One of the most feared and dangerous scenarios that can appear during an endoscopic endonasal surgery (EES) is the iatrogenic injury of the internal carotid artery (ICA). Several methods, along with a variety of outcomes, have been described to deal with this complication. To the authors' knowledge, this is the first report on the use of a Yasargil-type aneurysm clip to solve an ICA injury, preserving the artery's patency and having a long-term follow-up. The authors discuss the advantages and disadvantages of other vessel preservation techniques compared with clipping. OBSERVATIONS: A visually impaired 56-year-old woman was diagnosed with a giant nonfunctional pituitary tumor that invaded the sphenoidal sinus, anterior and posterior ethmoidal cells, and both cavernous sinuses, with suprasellar extension and optochiasmatic compression. The patient underwent EES, and during the final resection phase her left ICA was injured, with massive hemorrhage. LESSONS: ICA injury during endoscopic skull base surgery carries high mortality and morbidity; it is essential to maintain carotid flow when possible to avoid short-term and long-term consequences. There are several techniques depicted in the literature to deal with this situation. The authors report the use of a Yasargil mini-clip to deal with the injury for a positive outcome: primary hemostasis, vessel preservation, and no postoperative complications.

Role of Intraoperative Neurophysiologic Monitoring in Internal Carotid Artery Injury During Endoscopic Endonasal Skull Base Surgery.

OBJECTIVE: In the present study, we investigated the role of intraoperative neuromonitoring (IONM) in internal carotid artery (ICA) injury during endoscopic endonasal skull base surgery (EESBS). METHODS: The study group included all 13 patients who had experienced an ICA injury during EESBS with IONM from 2004 to 2017. The medical records were reviewed for the perioperative data. The IONM reports were reviewed to evaluate the baseline somatosensory evoked potentials (SSEP), electroencephalography (EEG), and brainstem auditory evoked potentials (BAEP) and their significant changes related to ICA injury and/or the subsequent surgical/endovascular interventions. RESULTS: All 13 patients had undergone SSEP and 7 patients had BAEP monitoring during surgery. EEG was added during emergent angiography following the surgery for 5 patients. Two patients showed significant SSEP changes, and one showed significant SSEP and EEG changes, indicating cerebral hypoperfusion. Of these 3 patients, patient 1 had experienced irreversible SSEP loss with postoperative stroke. Patients 2 and 3 had SSEP and/or EEG changes that had recovered to baseline after interventions without postoperative deficits. Despite ICA injury, 10 patients showed no significant SSEP and/or EEG changes, and all 7 patients with BAEP monitoring showed no significant BAEP changes, indicating adequate cerebral and brainstem perfusion, respectively. The injured ICA was sacrificed in 4 patients, of whom 3 showed stable SSEP and 1 had experienced irreversible SSEP loss. IONM correlated with the postoperative neurologic examination findings in all cases, adequately predicting the neurologic outcomes after ICA injury. CONCLUSION: SSEP and EEG monitoring can accurately detect cerebral hypoperfusion and provide real-time feedback during surgery. SSEP and EEG changes predicted for neurologic outcomes and guide surgical decisions regarding the preservation or sacrifice of the ICA. Comprehensive multimodality monitoring according to the surgical risks can serve to detect and guide the management of ICA injury in EESBS.

Internal carotid artery injury in the endoscopic transsphenoidal surgery for pituitary adenoma: an uncommon case and literature review.

Complications of the transsphenoidal surgery (TSS) for pituitary adenoma (PA) include vascular injury, nerve injury and nervous system infection. Among these, the consequences of internal carotid artery (ICA) injury are the most serious, and its mortality and disability rates are very high. The TSS was used in 889 patients with PA, among which there was 1 case of ICA injury. In this uncommon case of bromocirptine-resistant macro-prolatinoma, the patient had received an ultrahigh dose of oral bromocriptine for almost three years and was intraoperatively found to have a tenacious tumor texture and close adhesion of the tumor capsule to the ICA. Resection of the tumor capsule required excessive force, resulting in the rupture at the A1 origin of the left ICA. Endovascular balloon occlusion was used after urgent angiography. The patient died in two weeks even with intensive treatment. Although the underlying mechanism is still obscure, bromocriptine-inducing tumor fibrosis in PA is relatively common. For these patients with excessive dose of bromocriptine, tumor fibrosis and ICA injury should be seriously considered and performing a complete preoperative imaging evaluation to achieve accurate intraoperative positioning and carefully performing the operation are needed to preventing ICA injury. In some cases, resection of the tumor pseudocapsule should not be forced to avoid ICA injury.

Management of Noncatastrophic Internal Carotid Artery Injury in Endoscopic Skull Base Surgery.

Arterial injuries are the most feared complication of endoscopic skull base surgery. During resection of the middle fossa component of a large ventral skull base chondrosarcoma, arterial bleeding was encountered near the right internal carotid artery (ICA). Durable hemostasis could not be achieved with packing and the patient was taken for an emergent angiogram that revealed a pseudoaneurysm of the proximal intradural ICA. Given the presence of good collateral flow through the anterior and posterior communicating arteries, the right ICA was sacrificed by coil embolization. The patient was taken back to the operating room for closure then transferred to the intensive care unit and maintained on vasopressors for five days to ensure adequate perfusion. The right ICA was coil embolized and the patient was taken back to the operating room for closure. The patient recovered without complication. Arterial injuries, although serious, are not always catastrophic. Critical steps are immediate recognition of bleeding, vascular imaging, and vessel sacrifice if necessary.

Surgical simulation of a catastrophic internal carotid artery injury: a laser-sintered model.

BACKGROUND: The catastrophic and rare nature of an internal carotid artery (ICA) injury during endonasal surgery limits training opportunities. Cadaveric and animal simulation models have been proposed, but expense and complicated logistics have limited their adoption. Three-dimensional (3D) printed models are portable, modular, reusable, less costly, and proven to improve psychomotor skills required for managing different lesions. In this study we evaluate the role of a simplified laser-sintered model combined with standardized training in improving the effectiveness of managing an ICA injury endoscopically. METHODS: A 3-mm defect was created in the parasellar carotid canal of a laser-sintered model representing a sphenoid sinus. Artificial blood was directed to simulate the copious bleeding arising from an ICA injury. Twenty otolaryngologists and 26 neurosurgeons, with varying training and experience levels, were individually asked to stop the "bleeding" as they would in a clinical scenario, and provided no other instructions. This was followed by individualized formative training and a second simulation. Volume of blood loss, time to hemostasis, and self-assessed confidence scores were compared. RESULTS: At the end of the study, time to hemostasis was reduced from 105.49 seconds to 40.41 seconds (p < 0.001). The volume of blood loss was reduced from 690 to 272 mL (p < 0.001), and the confidence scores increased in 95.7% of participants, from an average of 3 up to 8. CONCLUSION: This ICA injury model, along with a formal training algorithm, appears to be valuable, realistic, portable, and cost-effective. Significant improvement in all parameters suggests the acquisition of psychomotor skills required to control an ICA injury.