Internal Carotid Artery Injury Research Articles

Report on Pseudoaneurysm Caused by Injury of Internal Carotid Artery During Endoscopic Pituitary Surgery and Rebleeding After Treatment With Willis Covered Stent.

Report on a case of pseudoaneurysm which was caused by injury of the internal carotid artery (ICA) during endoscopic endonasal surgery (EES), which was followed by rebleeding after treatment with a Willis covered stent. A woman, aged 68, underwent EES for the treatment of a pituitary adenoma. During the surgery, the right ICA was injured, and successfully hemostasis by packed with cottonoid and gelatin sponge. Besides, cerebral angiography was performed in the interventional operating room for the purpose of discovering the formation of a pseudoaneurysm in the cavernous sinus segment of ICA, which was treated with a covered stent. After successfully placing the covered stent, the patient was promptly transferred to the general operating room for the removal of the cottonoid and to address the bleeding once again. The authors employ crushed muscles and cottonoid to locally compress and stop bleeding. Owing to concerns about the risk of rebleeding in the patient, after stent implantation, the patient did not utilize antiplatelet drugs. After the surgery, the patient developed occlusion of the right ICA and massive cerebral infarction in the right hemisphere. Dehydration, anti-infection, rehabilitation, hyperbaric oxygen, as well as related treatments, were given. The cottonoid was removed in EES 2 months postsurgery, and no instances of bleeding were observed. Six months after surgery, the patient had clear consciousness and hemiplegia in the left limb, with a Glasgow Outcome Scale score of 4. The ICA was injured during EES, which resulted in the formation of a pseudoaneurysm, the Willis stent was adopted for treatment, and there was a risk of rebleeding after the nasal packing (cottonoid, crushed muscles) was removed immediately. The ICA was injured during EES after bleeding was controlled by packing with cottonoid, crushed muscles, etc, subsequently, the patient was given intravascular treatment, it is advised to make thorough preparations and, after a suitable period, remove nasal packing in the hybrid operating room to address unexpected situations and unforeseen circumstances.

Bilateral vertebral artery injury leads to brain death following traumatic brain injury: a case report

BackgroundVertebral artery injury is a rare condition in trauma settings. In the advanced stages, it causes death.CaseA 31-year-old Sundanese woman with cerebral edema, C2–C3 anterolisthesis, and Le Fort III fracture after a motorcycle accident was admitted to the emergency room. On the fifth day, she underwent arch bar maxillomandibular application and debridement in general anesthesia with a hyperextended neck position. Unfortunately, her rigid neck collar was removed in the high care unit before surgery. Her condition deteriorated 72 hours after surgery. Digital subtraction angiography revealed a grade 5 bilateral vertebral artery injury due to cervical spine displacement and a grade 4 left internal carotid artery injury with a carotid cavernous fistula (CCF). The patient was declared brain death as not improved cerebral perfusion after CCF coiling.ConclusionsBrain death due to cerebral hypoperfusion following cerebrovascular injury in this patient could be prevented by early endovascular intervention and cervical immobilisation.

A computed tomography (CT)-based morphometric study of various skull base parameters and their anatomical relationships relevant to endoscopic endonasal skull base surgery.

Endoscopic skull base surgery requires a thorough understanding of skull base anatomy. Orientation to regional anatomy to avoid complications like internal carotid artery injury can be assisted by knowledge of certain bony landmarks. These landmarks are themselves highly variable structures. This study focuses on the radiological morphometric characterization of these landmarks, which can be of great assistance to surgeons for better planning of endoscopic skull base approaches. Computed tomography scans of patients without skull base pathologies were analyzed retrospectively for the following parameters - Vidian canal (VC) length, VC and foramen rotundum (FR) distance from midline, the angle between the axis of VC and petrous internal carotid artery (pICA) and between VC and palatovaginal canal, the horizontal, vertical and direct distances between VC and FR and the patterns of sphenoid sinus (SS) pneumatization. The VC-pICA angle was more obtuse and VC and FR were placed farther off the midline on the left as compared to the right side. Similarly, the distances between VC and FR were more on the left side. The VC length and distance of VC and FR from the midline were longer in males than in females. The VC-pICA angle was more obtuse in females. The post-sellar variant was the predominant pneumatization pattern seen (57.9%), and the incidence of lateral recess pneumatization was 15%. The results of our study can be utilized for a better understanding of the anatomy of the skull base. In skull base pathologies with distorted anatomical landmarks, a basic understanding of their interrelations can be used to have a better anatomical orientation. All these measures can help in avoiding complications and make extended endoscopic approaches safe.

Utilization of Polydioxanone Plate for Endoscopic Anterior Skull Base Repair: Operative Technique and Long-Term Cohort Outcomes

Abstract Objective The purpose of this study is to report the technical procedure and our experience using a polydioxanone suture (PDS) plate with dural substitute as part of a fully resorbable gasket seal technique to repair anterior skull base defects. Methods A series of patients undergoing anterior skull base reconstruction utilizing our resorbable gasket seal technique from January 2014 to July 2022 was reviewed. Results A total of 155 patients were included. Nine (5.8%) of the included patients developed postoperative cerebrospinal fluid (CSF) leaks requiring reoperation. There were no cases of intraoperative cranial nerve injury or internal carotid artery injury. A total of 103 (66.5%) patients were observed to have an intraoperative CSF leak, including 57 low-flow leaks and 46 high-flow leaks; 1 of 57 (1.8%) patients with low-flow leaks and 8 of 46 (17.4%) patients with high-flow leaks developed a postoperative CSF leak. During the first 3 years that this technique was utilized at our center for the management of high-flow intraoperative CSF leaks, postoperative CSF leaks were documented in 4 of 12 (33.3%) patients, in comparison to 4 of 34 (11.8%) in the following years. Conclusion PDS plate reconstruction confers several advantages and can be used in a diverse set of operative scenarios in conjunction with other reconstruction options. There appeared to be an associated learning curve as surgeons at our center gained experience with this new technique. Our findings show that the PDS plate reconstruction is safe and effective in repairing the skull base.

Further investigation of the lateral approach for the resection of Knosp grade 4 pituitary adenomas in endoscopic endonasal surgery.

The authors performed a further in-depth study of the lateral compartment of the cavernous sinus (LCCS) by the endoscopic endonasal approach to improve the safety and efficacy of the lateral approach for the removal of Knosp grade 4 pituitary adenomas (KG4PAs). Twenty-three cadaveric specimens were used for endoscopic endonasal dissection, and the LCCS was exposed to observe the neurovascular and fibrous structures within. A subclassification of the lateral approach based on further knowledge of the LCCS was proposed and used to resect 86 KG4PAs, and the surgical outcomes of these cases were reviewed. Type A KG4PAs represent tumor that was mainly distributed in the posterosuperior and superolateral compartments, type B KG4PAs represent tumor that was mainly distributed in the anteroinferior compartments, and type AB KG4PAs represent tumor that extended into each compartment with characteristics of types 4A and 4B. The authors identified multiple fibers that anchored the horizontal segment of the internal carotid artery (ICA) to the abducens nerve. The fibers, the sympathetic nerve, and the inferior lateral trunk form a partition-like structure in the LCCS named the abducens nerve-ICA complex (AIC), and the LCCS can be divided into the superolateral and inferolateral compartments by the AIC. Accordingly, the lateral approach was subclassified into the lateral superior (LS) approach and the anterior inferior (AI) approach. The LS approach was mainly used to resect type A KG4PAs, whereas the AI approach was used to resect type B KG4PAs, and a combination of the two was used to resect type AB KG4PAs. The gross-total, subtotal, and partial resection rates were 81.4%, 12.8%, and 5.8%, respectively. The numbers of cases of postoperative transient cranial nerve palsy, postoperative permanent cranial nerve palsy, ICA injury, and CSF leakage were 6 (6.9%), 2 (2.3%), 1 (1.2%), and 1 (1.2%), respectively. This study revealed that the LCCS is divided by the AIC into the superolateral and inferolateral compartments, avoiding the misconception that the LCCS has vertical communication. Therefore, the lateral approach was subclassified into the LS approach and the AI approach for the resection of KG4PAs, which allowed a high gross-total resection rate with acceptable safety in the surgical treatment of KG4PAs.

Preoperative Imaging in Patients with 22q11 Deletion Syndrome Undergoing Velopharyngeal Surgery.

To evaluate the utility of preoperative imaging before velopharyngeal dysfunction (VPD) surgery in children with 22q11 Deletion Syndrome (22qDS) in evaluating internal carotid artery (ICA) medialization. PubMed, Scopus, and CINAHL. Following PRISMA guidelines, a systematic review was performed. Studies of children with 22qDS who underwent preoperative imaging (MRA or CTA) to identify ICA anomalies were included. High-risk medialized ICAs were defined as either submucosal, retropharyngeal, Pfeiffer Grade III-IV, or <3 mm from the pharyngeal mucosa. Meta-analyses of proportions were performed. Eleven studies met inclusion criteria, comprising 398 patients with 22qDS (weighted mean age 7.6 years). In 372 patients with imaging, the rate of ICA medialization on imaging was 47.1% (95%CI 29.2-65.5), of which 46.3% (95%CI 27.4-65.8) were determined high risk. Operative plans were modified in 19.4% (95%CI 5.7-38.8) of 254 surgeries due to medialized ICA. In studies attempting to use nasopharyngoscopy pulsations to identify medialization for 214 patients, the true-positive rate was 53.9% (95%CI 27.5-79.2) and the false-positive rate was 16.2% (95%CI 7.9-26.8). Nine of eleven studies (81.8%) recommended universal preoperative imaging of the ICAs in children with 22qDS undergoing VPD surgery. No cases of perioperative bleeding secondary to ICA injury were identified. Although most studies endorse routine preoperative imaging to assess for ICA medialization in children with 22qDS undergoing VPD surgery, only a minority of these cases led to surgical modification. Additional studies are needed to compare outcomes in children with and without preoperative imaging given the low rates of ICA injury in the literature. N/A Laryngoscope, 134:2551-2561, 2024.

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

BackgroundTranssphenoidal 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. MethodsWe 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. ResultsSix patients experienced an ICA injury. All received timely and effective hemostasis with immediate direct tamponade followed by endovascular treatment. No serious postoperative complications occurred. ConclusionsWe 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.

Pituitary adenoma with oculomotor cistern extension: membranous anatomy and clinical application.

The anatomical basis of pituitary adenomas (PAs) with oculomotor cistern (OC) extension as a growth corridor is overlooked in the literature. In this paper, the authors use the technique of epoxy sheet plastination to study the membranous structure of the OC and validate the results by retrospective analysis of patients with OC extension. Eighteen specimens were used to study the membranous anatomy surrounding the OC using the epoxy sheet plastination technique. Thirty-four patients with OC extension were retrospectively reviewed. The OC consisted of two thin membranous layers. The inner layer was extended by the arachnoid layer from the posterior fossa, and the lateral layer consisted of the dura mater sinking from the roof of the cavernous sinus. The oculomotor nerve is more likely to displace with a superolateral trajectory due to the weakness of the posterior dura and the relatively large space in the medial and posterior trajectories, which is consistent with the intraoperative observations. Among the anatomical factors that affect the PA by OC extension, we found that the relative position of the internal carotid artery (ICA) and posterior clinoid process may lead to the narrowing of the OC. Of 34 cases, 28 patients achieved total resection. Among 24 preoperative patients with oculomotor nerve palsy, 16 cases were relieved to varying degrees postoperatively. There was no ICA injury or severe intracranial infection found in any of the patients. Extension into the OC is influenced by two anatomical factors: a weak point in the dura in the posterior OC and a potential space beyond this region of the dura. Meticulous knowledge of the membranous anatomy in endoscopic endonasal surgery is required to safely and effectively resect PA with OC extension.

Epidemiology, repair technique, and predictors of stroke and mortality in penetrating carotid artery injuries

ObjectivePenetrating carotid artery injuries (PCAI) are significantly morbid and deadly, often presenting in extremis with associated injuries and central nervous system deficit. Repair may be challenging with arterial reconstruction vs ligation role poorly defined. This study evaluated contemporary outcomes and management of PCAI. MethodsPCAI patients in the National Trauma Data Bank from 2007 to 2018 were analyzed. Outcomes were compared between repair and ligation groups after additionally excluding external carotid injuries, concomitant jugular vein injuries, and head/spine Abbreviated Injury Severity score of ≥3. Primary end points were in-hospital mortality and stroke. Secondary end points were associated injury frequency and operative management. ResultsThere were 4723 PCAI (55.7% gunshot wounds, 44.1% stab wounds). Gunshot wounds more frequently had associated brain (73.8% vs 19.7%; P < .001) and spinal cord (7.6% vs 1.2%; P < .001) injuries; stab wounds more frequently had jugular vein injuries (19.7% vs 29.3%; P < .001). The overall in-hospital mortality was 21.9% and the stroke rate was 6.2%. After exclusion criteria, 239 patients underwent ligation and 483 surgical repair. Ligation patients had lower presenting Glasgow Coma Scale (GCS) than repair patients (13 vs 15; P = .010). Stroke rates were equivalent (10.9% vs 9.3%; P = .507); however, in-hospital mortality was higher after ligation (19.7% vs 8.7%; P < .001). In-hospital mortality was higher in ligated common carotid artery injuries (21.3% vs 11.6%; P = .028) and internal carotid artery injuries (24.5% vs 7.3%; P = .005) compared with repair. On multivariable analysis, ligation was associated with in-hospital mortality, but not with stroke. A history of neurological deficit before injury lower GCS, and higher Injury Severity Score (ISS) were associated with stroke; ligation, hypotension, higher ISS, lower GCS, and cardiac arrest were associated with in-hospital mortality. ConclusionsPCAI are associated with a 22% rate of in-hospital mortality and a 6% rate of stroke. In this study, carotid repair was not associated with a decreased stroke rate, but did have improved mortality outcomes compared with ligation. The only factors associated with postoperative stroke were low GCS, high ISS, and a history of neurological deficit before injury. Beside ligation, low GCS, high ISS, and postoperative cardiac arrest were associated with in-hospital mortality.

Endoscopic Extended Transsphenoidal Surgery Aiming for Radical Resection of Skull Base Tumors Involving Cavernous Sinus: Assessment of Resectability and Risks of Complications.

Surgical resection of tumors invading the cavernous sinus (CS) still shows therapeutic challenges. For "nonadenomatous" skull base tumors invading in CS, there were only a few reports showing the outcomes of radical resection. Therefore, the outcomes of endoscopic transsphenoidal surgery (ETS) aiming for radical resection thus remain largely unknown regarding resectability and functional results of the cranial nerves. We performed ETS aiming for radical resection in 35 skull base tumors involving CS (17 chondrosarcomas, 12 chordomas, 3 meningiomas, and 3 trigeminal schwannomas; median follow-up 36.5 months ranging from 12 to 91 months). Gross total resection (GTR) is attempted in all the cases for real-time findings from electrophysiological monitoring of the cranial nerves. When the tumor was strongly adherent to the cranial nerves or internal carotid artery, maximum volume reduction of the tumor was attempted. GTR was achieved in 28 patients (80.0%), subtotal resection in 3 (8.6%), and partial resection in 4 (11.4%). One patient experienced internal carotid artery injury during surgery. After ETS, 15 patients showed symptom improvement (51.7% in all 29 patients with preoperative cranial nerve symptoms, CNS). Four (11.4%) transiently developed abducens nerve palsy, and one required repair surgery for cerebrospinal leakage. In univariate analyses, extension to the lateral compartment of CS ( P = .04) was significantly associated with reduced achievement of GTR. Previous transcranial surgery was associated with reduced possibility of improvement and worsening in CNS. Eleven patients underwent stereotactic radiosurgery, at a median of 12 months after ETS. 32 patients (91.4%) did not show recurrence at the final follow-up. ETS can achieve sufficient surgical resection in most of the patients, with acceptable neurological complications. For patients with CNS, ETS may offer the opportunity for improving CNS. We should also always prioritize avoidance of critical situations by preventing internal carotid artery injury.

Endoscopic Endonasal Approach for Trigeminal Schwannomas: Tailored Approaches Based on Lesion Traits.

To describe four endoscopic endonasal subapproaches, namely, the trans-lamina papyracea, trans-prelacrimal recess, trans-Meckel's cave, and transclival approaches for trigeminal schwannomas (TSs). This retrospective study reviewed the medical records and intraoperative videos of 38 patients with TSs who underwent endoscopic endonasal approach (EEA) between Jan 2013 and Dec 2021. According to Jeong's classification, for TS equally in middle and posterior fossae (MP), a purely trans-Meckel's cave approach was carried out in 2 cases, and a combined transclival approach was carried out in 4 cases. The four tumors that involved infratemporal fossa (two E3, one mE3, and one Mpe3) were performed via a trans-prelacrimal recess approach, and type Mpe3 was also assisted by the trans-Meckel's cave approach. One patient with type E1 was treated with a trans-lamina papyracea approach. The other 27 cases, including type M, Mp, ME2, and MpE2, were all removed by a purely trans-Meckel's cave approach. Thirty-six patients (97.4%) received total resection under a purely EEA. The functional abilities and preoperative symptoms of 31 patients (88.6%) improved. Eight (21.1%) patients experienced permanent neurological function deficits. Postoperative cerebrospinal fluid and intraoperative internal carotid artery injury occurred in 1 (2.6%) patient. According to the specific endoscopic endonasal subapproaches corresponding to the different TS locations, satisfactory results can be obtained for most types of tumors. It represents an effective alternative to the open transcranial approach and can also be properly used in most types of TS with experienced hands. 4 Laryngoscope, 2023.

Fracture of the Petrous Carotid Canal

A 23-year-old male motorcyclist experienced blunt head trauma with loss of consciousness, headache and vomiting, epistaxis and right otorrhagia after a collision with a motor vehicle. Fractures involving the right parietal and temporal bones, as well as acute subdural and subarachnoid hemorrhage were identified on a cranial and facial CT scan. On independent evaluation of the imaging study, a subtle but distinct fracture line in the skull base involving the petrous carotid canal was identified. (Figure 1) The patient subsequently underwent CT angiography to evaluate for any injury to the internal carotid artery. In this examination, good opacification of the internal carotid arteries and their branches was noted, with no evident aneurysm, arteriovenous malformation or arteriovenous fistula formation.&#x0D; In patients with temporal bone fractures, the most commonly encountered complications are: tympano-ossicular injury causing conductive hearing loss, cochlear or vestibular injury causing sensorineural hearing loss or vertigo, facial nerve trauma causing facial paralysis, and fractures of the tegmen or posterior cranial fossa plate causing cerebrospinal fluid leaks.1 On the other hand, injury to the intratemporal portion of the internal carotid artery has been described as a rare complication and as such may be overlooked.1 However, its potentially devastating and life-threatening sequelae necessitates a purposeful and intentional evaluation for its presence. These sequelae include brain ischemia from arterial dissection or complete vascular occlusion, exsanguinating epistaxis or otorrhagia from carotid pseudoaneurysms, and the formation of carotid-cavernous fistulas.2 The incidence of involvement of the carotid canal in skull base fractures has been reported to be around 24%, with around 11% of this group developing internal carotid artery injuries.3 As such, the presence of fractures involving the petrous carotid canal is an indication for CT or MR angiography to further evaluate the internal carotid artery.4

Internal carotid artery injury during endoscopic endonasal surgery for skull base pathologies: an institutional incidence, management, and outcome.

Endoscopic endonasal surgery (EES) has become a popular approach to deal with skull base pathologies. The most catastrophic intra-operative complication of EES is internal carotid artery (ICA) injury. We aim to discuss and introduce our institutional experience with ICA injury during EES. A retrospective review of patients who underwent EES from 2013 to 2022 was performed to determine the incidence and outcomes of intraoperative ICA injuries. There were six patients (0.56%) with intraoperative ICA injury in our institution during the last 10 years. Fortunately, there was no morbidity or mortality in our patients with intraoperative ICA injuries. The sites of injury were equally in paraclival, cavernous sinus, and preclinoidal segments of ICA. Primary prevention is the best solution for this condition. Regarding our institutional experience, the best option for primary management just after an injury is packing the surgical site. In cases where packing is not enough for temporary control of bleeding, common carotid artery occlusion should be considered. We have presented our experience and reviewed previous studies regarding different treatments and suggested our intra and post-operative management algorithm.

Endoscopic Repair of Internal Carotid Artery Injury with a Lateral Tongue Muscle Patch Graft: Novel Technique and Literature Review.

Objectives Iatrogenic injury to the internal carotid artery (ICA) is one of the most catastrophic complications of endoscopic sinus and skull base surgery. Previous research has shown that packing with a crushed muscle graft at the injury site can be an effective management technique to control bleeding and prevent the need for ICA sacrifice. Here, we describe a novel and readily available repair donor site-an autologous lateral tongue muscle patch. Design Three representative cases of a successful repair of ICA injuries using a lateral tongue muscle patch are included in this study. The graft measured approximately 2 × 3 cm and was taken from the lateral intrinsic tongue musculature. We describe the harvest of the graft, its advantages, and the details of operative repair. Results The lateral tongue provides a large and readily accessible source of muscle within the surgical field that can be quickly harvested during an endoscopic procedure. For the first case, an expanding parasellar ICA pseudoaneurysm was managed with a tongue muscle patch and nasal packing. In the second case, a cavernous ICA injury was sustained during craniopharyngioma resection. Case three involved an ICA injury during endonasal debridement of invasive fungal rhinosinusitis. None of the patients required embolization or neurovascular stenting. Postoperative angiograms and serial computed tomography angiograms showed complete resolution of the pseudoaneurysm, and the patients continued to do well at least 1 year after repair. Conclusion Lateral tongue muscle graft is an effective and efficient method to manage ICA injuries during endoscopic endonasal surgery. Advantages include the speed of harvest, donor site being readily accessible in the surgical field, and low donor site morbidity. It should be added to the repertoire of possible donor sites for addressing catastrophic sinonasal bleeding.

A new potential risk factor for permanent cranial nerve injury following carotid body tumor resection

To quantify the association between the free distal segment length of the internal carotid artery (FDS-ICA) and permanent cranial nerve injury (p-CNI) following carotid body tumor (CBT) resection. This study is a case-control study. We surveyed 109 consecutive patients who underwent CBT resection between June 2015 and June 2020 at our single center. A total of 89 patients met the inclusion criteria and were selected for analysis. The FDS-ICA was measured by image post-processing software for computed tomography angiography (CTA). Postoperative p-CNI complications were evaluated using comprehensive statistical approaches. The cohort was divided into 2 groups depending on the presence of p-CNI, namely the p-CNI group (n=17) and the non-CNI group (n=79). The average FDS-ICA of patients with p-CNI complications was shorter than that of those without p-CNI complications (P<0.001). For every 1 mm increase in FDS-ICA, there was an associated decrease of 8% in the risk of p-CNI (0.92, 95% CI: 0.85 to 0.98, P<0.05). Threshold effect analysis of the FDS-ICA on p-CNI identified that the FDS-ICA was 28.7 (95% CI: 23.8 to 30.9) mm. The results of this study revealed a significant independent association between FDS-ICA and permanent postoperative cranial nerve injury complications of CBTs. Further study is warranted to confirm these results in a larger patient cohort.

Internal carotid artery position to characterize risk for vessel injury in pediatric intraoral trauma.

The internal carotid artery (ICA) lies in close anatomic proximity to the oropharynx and is at risk for injury in the instance of intraoral trauma. The objectives of this study are to describe the position of the ICA relative to the oropharynx and identify patient risk factors related to its position. A total of 100 patients aged 12 months to 7 years 11 months who received computed tomography (CT) of the neck were randomly selected. The position of the ICA was determined by measuring its angular location relative to the center of the oropharynx (ICA angle) and the shortest distance from the oropharyngeal surface (OP-ICA distance). Indication for imaging was controlled for in all reported data. Patient age was related to ICA angles on both the left (F=8.06; P=0.01; η2=0.08, 95% CI: 0.01-0.19) and right (F=18.62; P<0.001; η2=0.17, 95% CI: 0.05-0.29). Patient weight also was related to ICA angles on both the left (F=7.08; P=0.01; η2=0.07, 95% CI: 0.01-0.18) and right (F=11.86; P<0.001; η2=0.11, 95% CI: 0.02-0.24). Patient age was related to the left OP-ICA distance (F=7.36; P=0.01; η2=0.07, 95% CI: 0.01-0.19), as was patient weight (F=4.82; P=0.03; η2=0.05, 95% CI: 0.00-0.15). Across all measurements, no significant relationship was identified between ICA position and other patient variables, including sex and race/ethnicity. The ICA of younger patients and those with lower body weight may be located more medially within the neck and closer to the oropharyngeal surface. This vessel position may place these children at greater anatomic susceptibility for ICA injury in the event of intraoral trauma.

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

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. 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). 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. 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.

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

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. 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 1L/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. The model proved to mimic a real intraoperative scenario of ICAI with an expected output flow of 1L/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. 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.

Endoscopic Endonasal Skull Base Surgery Complication Avoidance: A Contemporary Review.

The endoscopic endonasal approach (EEA) provides a direct trajectory to ventral skull base lesions, avoidance of brain retraction, and clear visualization of cranial nerves as they exit skull base foramina. Despite these benefits, the EEA is not without complications. Here, we review published literature highlighting complications associated with the EEA including cerebrospinal fluid (CSF) leak, cranial nerve (CN) dysfunction, pituitary gland dysfunction, internal carotid artery (ICA) injury, infection, and others; we place special emphasis on discussing the prevention of these complications. As widespread adoption of the EEA continues, it becomes critical to educate surgeons regarding potential complications and their prevention while identifying gaps in the current literature to guide future research and advances in clinical care.

Subclassification of Knosp Grade 4 Pituitary Adenoma: Bringing Insights Into the Significance of Tumor Growth Pathways.

Understanding the growth pathway of Knosp grade 4 pituitary adenoma (KG4PA) has a direct impact on surgical planning and safety for tumor eviction. To analyze the different characteristics between KG4PAs with a focus on the tumor growth pathway and its relationship to the cavernous segment of internal carotid artery. Clinical data from 129 patients with KG4PAs who underwent endoscopic endonasal surgery were retrospectively reviewed. A subclassification scheme was proposed based on the tumor growth pathway and its relevant features. The clinical connotation of the subclassification on surgical outcomes was also analyzed. The KG4PAs were classified into 3 types based on the tumor growth pathway and its relevant features: groups A, B, and AB. The gross total resection rate in group A (51.2%) was much lower than that in group B (87.5%) and AB (87%) with a significant difference between the 3 groups ( P = .0004). The overall rate of visual function improvement, preoperative cranial nerve (CN) palsy improvement, and postoperative hormonal remission was 85.1%, 83.3%, and 85.7%, respectively. The rate of transient CN palsy, permanent CN palsy, permanent diabetes insipidus, panhypopituitarism, CSF leakage, and internal carotid artery injury was 7.8%, 3.9%, 4.7%, 2.3%, 1.5%, and 0.7%, respectively. The subclassification strengthens our understanding of KG4PAs on tumor growth corridors and topographic relations of tumor and cavernous segment of internal carotid artery. Furthermore, the distinction into groups 4A, 4B, and 4AB is of benefits for selecting approaches, predicting risk and avoiding complications, and generating more tailored individualized surgical strategies for KG4PAs with better outcomes.