Iatrogenic carotid artery injury in neurosurgery

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.

Endovascular Treatment of Vascular Injuries in the Craniocervical Region With a Graft Stent: A Single-Center Experience

AIM

We aimed to evaluate the efficacy and safety of graft stent implantation in the endovascular treatment of vascular injuries in the craniocervical area.

MATERIALS AND METHODS

This study was carried out through the retrospective screening of eight (two females and six males) patients' records. Patients who used graft stents as an endovascular method were included in the study. The mean age of the patients was 43.6 years (with a range of 15-69 years). Due to different mechanisms, the patients had vascular injuries in the craniocervical region, and graft stent implantation was performed between 2010 and 2022. We evaluated patient demographics, admission symptoms, trauma mechanisms, angiographic findings, treatment modalities and materials, patient outcomes, and follow-up periods.

RESULTS

Due to iatrogenesis for four patients, penetrating trauma for three patients, and blunt trauma for one patient, injuries were present in the right internal carotid artery {ICA} (n=1), left ICA (n=1), left common carotid artery {CCA} (n=3), right CCA (n=1), right vertebral artery (n=1), and left vertebral artery (n=1). Angiographically, pseudoaneurysm was detected in seven patients, and vascular rupture was detected in one patient using contrast agent extravasation. All patients who underwent the endovascular method had technical success. Since bleeding from the external carotid artery branches was seen in two patients, these branches were embolized with coils. No radiologically or neurologically pathological findings were recorded during the follow-up period (with a range of one week to 12 years).

CONCLUSION

Graft stent use in the endovascular treatment of craniocervical vascular injuries is an operable, safe, and promising option, especially in patients with pseudoaneurysms and active bleeding.

A New Perspective on the Cavernous Sinus as Seen through Multiple Surgical Corridors: Anatomical Study Comparing the Transorbital, Endonasal, and Transcranial Routes and the Relative Coterminous Spatial Regions

Background: The cavernous sinus (CS) is a highly vulnerable anatomical space, mainly due to the neurovascular structures that it contains; therefore, a detailed knowledge of its anatomy is mandatory for surgical unlocking. In this study, we compared the anatomy of this region from different endoscopic and microsurgical operative corridors, further focusing on the corresponding anatomic landmarks encountered along these routes. Furthermore, we tried to define the safe entry zones to this venous space from these three different operative corridors, and to provide indications regarding the optimal approach according to the lesion's location. Methods: Five embalmed and injected adult cadaveric specimens (10 sides) separately underwent dissection and exposure of the CS via superior eyelid endoscopic transorbital (SETOA), extended endoscopic endonasal transsphenoidal-transethmoidal (EEEA), and microsurgical transcranial fronto-temporo-orbito-zygomatic (FTOZ) approaches. The anatomical landmarks and the content of this venous space were described and compared from these surgical perspectives. Results: The oculomotor triangle can be clearly exposed only by the FTOZ approach. Unlike EEEA, for the exposure of the clinoid triangle content, the anterior clinoid process removal is required for FTOZ and SETOA. The supra- and infratrochlear as well as the anteromedial and anterolateral triangles can be exposed by all three corridors. The most recently introduced SETOA allowed for the exposure of the entire lateral wall of the CS without entering its neurovascular structures and part of the posterior wall; furthermore, thanks to its anteroposterior trajectory, it allowed for the disclosure of the posterior ascending segment of the cavernous ICA with the related sympathetic plexus through the Mullan's triangle, in a minimally invasive fashion. Through the anterolateral triangle, the transorbital corridor allowed us to expose the lateral 180 degrees of the Vidian nerve and artery in the homonymous canal, the anterolateral aspect of the lacerum segment of the ICA at the transition zone from the petrous horizontal to the ascending posterior cavernous segment, surrounded by the carotid sympathetic plexus, and the medial Meckel's cave. Conclusions: Different regions of the cavernous sinus are better exposed by different surgical corridors. The relationship of the tumor with cranial nerves in the lateral wall guides the selection of the approach to cavernous sinus lesions. The transorbital endoscopic approach can be considered to be a safe and minimally invasive complementary surgical corridor to the well-established transcranial and endoscopic endonasal routes for the exposure of selected lesions of the cavernous sinus. Nevertheless, peer knowledge of the anatomy and a surgical learning curve are required.

Carotid artery dissections from transcarotid artery revascularization as reported by the Food and Drug Administration

OBJECTIVES

Transcarotid artery revascularization (TCAR) is a hybrid procedure that allows reversal of blood flow away from the brain while placing a stent through direct surgical access of the common carotid artery. It has been shown to have a lower risk of perioperative stroke compared with any prospective trial of transfemoral carotid artery stenting. However, intraoperative injuries related to the procedure and its management are not well characterized. One of the intraoperative complications seen in TCAR is iatrogenic carotid artery dissection (CD). We aim to add qualitative insight in further characterizing CDs and its management in this emerging technology.

METHODS

The Food and Drug Administration (FDA) maintains the Manufacturer and User Facility Device Experience (MAUDE) database for surveillance of all medical devices approved for use. This database was queried for all cases associated with Silk Road Medical's ENROUTE Transcarotid Neuroprotection System from September 2016 to October 2020. Case narratives related to CD were individually analyzed to determine time of injury (intraoperative, recovery, and post-discharge follow-up). CD reporting was further analyzed for the associated procedural event at the time of injury, number of access attempts to CD repair, and type of CD repair. Reports associated with CD repair were further categorized into endovascular repair and open surgical repair.

RESULTS

Of the 115 unique adverse events in the database, there were 58 CDs. Most were identified intraoperatively (n = 55), while three were incidentally found postoperatively. Overall, sheath placement was the most common procedural event attributed to CD (N = 34). There was adequate narrative information about CD repair in 54 patients. Intraoperative repair was performed in 52 cases and two were repaired after post-discharge follow-up imaging was performed.Among CDs that did not require additional access to engage the true lumen, the proportion of endovascular repair (62.5%) was significantly higher (p = .044) compared to the proportion of open surgical repair (37.5%). However, the proportion of open surgical repair (75%) was significantly higher than the proportion of endovascular repair (25%) in CDs with persistent failure to engage the true lumen despite ≥2 access attempts (p = .039).

CONCLUSION

CD is the most common injury related to TCAR as reported on MAUDE. The most commonly reported procedural event associated with CD was sheath placement. The rate of intraoperative endovascular and open surgical CD repair was associated with whether the access to the true lumen of the carotid artery required additional access attempts or not. This should add qualitative insight among the vascular surgery community regarding intraoperative management of CDs from a TCAR procedure.

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.

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.

An Institutional Experience and Literature Review on Iatrogenic Major Vascular Injury in Neurosurgery: Proposal of a Management Algorithm

Background

Major vessel injury is among the most dreaded complications of any neurosurgical procedure. Once intraoperatively tamponaded, it can present in the form of pseudoaneurysm, dissecting aneurysm or complete occlusion of vessel. These injuries are often associated with very high morbidity and mortality. The literature available on this topic is limited and our understanding remains limited.

Objective

In this article, we present our surgical experience with iatrogenic aneurysms and present a review of literature.

Methods and Material

We conducted a retrospective analysis of all patients with major vessel injury during surgery from a prospectively maintained database from January 2012 to February 2020.

Results

A total of 15 patients developed iatrogenic aneurysms following a major vessel injury during various neurosurgical procedures. The most common vessel injured was vertebral artery (n = 9) in craniovertebral junction (CVJ) anomalies and ossification of posterior longitudinal ligament (OPLL) followed by internal carotid artery injury (n = 5) in sellar and parasellar pathologies. One patient developed basilar artery injury during endoscopic third ventriculostomy (ETV). Eight patients had pseudoaneurysm and seven had dissecting aneurysm with or without complete thrombosis of the involved artery. A total of two patients died after vascular injury and remaining thirteen patients survived and discharged.

Conclusions

The adage "prevention is better than cure" applies most aptly in such cases. Any major vessel injury should be followed by immediate angiography and subsequent early management. The endovascular management is more favorable as these aneurysms are difficult to clip due to the absence of a neck and fragile wall.

Intraoperative Carotid Artery Injuries. Review of the literature, analysis of the material of one centre

<br><b>Introduction:</b> Injuries of the carotid artery constitute a rare group of injuries. This study presents results of the treatment of 44 patients with iatrogenic carotid artery injuries for over 20 years. The patients were treated by the team of doctors of the Department of Vascular, General and Transplant Surgery in Wroclaw in the years 1997–2017 (Head of the Department Prof. Klemens Skóra, MD, and Prof. Piotr Szyber, MD, PhD – material used with permission).</br> <br><b>Aim:</b> Aims of the analysis are: to estimate the frequency of different forms of iatrogenic injuries to the common and internal carotid artery, to evaluate the results of treatment, to assess the most effective surgical method depending on the type of injury, and develop an effective preoperative, intraoperative and postoperative regimen.</br> <br><b>Discussion and results:</b> The frequency of various carotid artery injuries (blunt, acute, traffic) was constant between years, but the number of iatrogenic injuries definitely increased over time. The prognosis for patients with carotid artery injury, especially when combined with multi-organ trauma, is the gravest. Significantly better treatment results were achieved with both acute and iatrogenic injuries. This is mainly due to easier and quicker diagnosis and better conditions for assisting patients.</br> <br><b>Conclusions:</b> In iatrogenic injuries, a well-designed surgical scheme, i.e. primarily the administration of UTH and placing a temporary suction drain by the first operating team, reduces the risk of neurological complications.</br>

The surgical management of intraoperative intracranial internal carotid artery injury in open skull base surgery-a systematic review

Intraoperative internal carotid artery (ICA) injury during open skull base surgery is a catastrophic complication. Multiple techniques and management strategies have been reported for endoscopic skull base surgery; however, the literature on managing this complication in open skull base surgery is limited. To perform a systematic review and give an overview of the different techniques described to manage this complication intraoperatively, a systematic review was conducted in PubMed, Ovid Medline, Ovid Embase and Scopus for literature published until July 2021. Titles and abstracts were screened. Studies meeting prespecified inclusion criteria were reviewed in full. PRISMA guidelines were strictly adhered to. Out of 4492 articles, only 12 articles could be included, reflecting an underreporting of open skull base ICA injuries. Multiple techniques can be used depending on the location and size of the injury as well as the surgeon's experience. Described techniques include the following: a primary repair via a micro-suture or nonpenetrating clips; wrapping or plugging; coating; occlusion of the parent artery with or without a bypass; packing with further endovascular management. A treatment algorithm is proposed.

Rating the incidence of iatrogenic vascular injuries in thoracic and lumbar spine surgery as regards the approach: A PRISMA-based literature review

PURPOSE

To assess the rate, timing of diagnosis, and repairing strategies of vascular injuries in thoracic and lumbar spine surgery as their relationship to the approach.

METHODS

PubMed, Medline, and Embase databases were utilized for a comprehensive literature search based on keywords and mesh terms to find articles reporting iatrogenic vascular injury during thoracic and lumbar spine surgery. English articles published in the last ten years were selected. The search was refined based on best match and relevance.

RESULTS

Fifty-six articles were eligible, for a cumulative volume of 261 lesions. Vascular injuries occurred in 82% of instrumented procedures and in 59% during anterior approaches. The common iliac vein (CIV) was the most involved vessel, injured in 49% of anterior lumbar approaches. Common iliac artery, CIV, and aorta were affected in 40%, 28%, and 28% of posterior approaches, respectively. Segmental arteries were injured in 68% of lateral approaches. Direct vessel laceration occurred in 81% of cases and recognized intraoperatively in 39% of cases.

CONCLUSIONS

Incidence of iatrogenic vascular injuries during thoracic and lumbar spine surgery is low but associated with an overall mortality rate up to 65%, of which less than 1% for anterior approaches and more than 50% for posterior ones. Anterior approaches for instrumented procedures are at risk of direct avulsion of CIV. Posterior instrumented fusions are at risk for injuries of iliac vessels and aorta. Lateral routes are frequently associated with lesions of segmental vessels. Suture repair and endovascular techniques are useful in the management of these severe complications.

Management of an Internal Carotid Artery Injury During Open Skull Base Surgery With a Crushed Muscle Patch - Technical Note and Lessons Learned

BACKGROUND

Iatrogenic internal carotid artery (ICA) injury is a catastrophic complication in open skull base surgery. There is a lack of information regarding the most appropriate techniques on how to manage this complication.

OBJECTIVE

To highlight the difficulties encountered when an ICA injury arises intraoperatively and discuss the role and the potential pitfalls of the crushed muscle patch in the management of an ICA injury during open skull base surgery.

METHODS

In this technical video, we demonstrate the management of intraoperative ICA injury, which occurred during the resection of a diffuse planum sphenoidale meningioma via a left pterional craniotomy.

RESULTS

When isolation of the defect with temporary clips failed, we opted for a crushed muscle graft to plug the defect. Hemostasis was achieved, but because of prolonged pressure application and "overpacking," the parent vessel was occluded.

CONCLUSION

The crushed muscle patch can be easily applied; however, care must be taken not to "overpack" and occlude the ICA.

Assessment of Factors Associated With Internal Carotid Injury in Expanded Endoscopic Endonasal Skull Base Surgery

Importance

Injury to the internal carotid artery (ICA) during endoscopic endonasal skull base surgery does not typically occur as an isolated circumstance but often is the result of multiple factors.

Objective

To assess the factors associated with ICA injury in an effort to reduce its occurrence.

Design, Setting, and Participants

This quality improvement study used a multicenter root cause analysis of ICA injuries sustained during endoscopic endonasal skull base surgery performed at 11 tertiary care centers across 4 continents (North America, South America, Europe, and Asia) from January 1, 1993, to December 31, 2018. A fishbone model was built to facilitate the root cause analysis. Patients who underwent an expanded endoscopic endonasal approach that carried a substantial potential risk of an ICA injury were included in the analysis. A questionnaire was completed by surgeons at the centers to assess relevant human, patient, process, technique, instrument, and environmental factors associated with the injury.

Main Outcomes and Measures

Root cause analysis of demographic, human, patient, process, technique, instrument, and environmental factors as well as mortality and morbidity data.

Results

Twenty-eight cases of ICA injury occurred during 7160 expanded endoscopic endonasal approach procedures (incidence of 0.4%). The mean age of the patients was 49 years, with a female to male predominance ratio of 1.8:1 (18 women to 10 men). Anatomical (23 [82%]), pathological (15 [54%]), and surgical resection (26 [93%]) factors were most frequently reported. The surgeon's mental or physical well-being was reported as inadequate in 4 cases (14%). Suboptimal imaging was reported in 6 cases (21%). The surgeon's experience level was not associated with ICA injury. The ICA injury was associated with use of powered or sharp instruments in 20 cases (71%), and use of new instruments or technology in 7 cases (25%). Two patients (7%) died in the operating room, and 3 (11%) were alive with neurological deficits. Overall, patient-related factors were the most frequently reported risk factors (in 27 of 28 cases [96%]). Factors associated with ICA injury catalyzed a list of preventive recommendations.

Conclusions and Relevance

This study found that human factors were associated with intraoperative ICA injuries; however, they were usually accompanied by other deficiencies. These findings suggest that identifying risk factors is crucial for preventing such injuries. Preoperative planning and minimizing the potential for ICA injury also appear to be essential.

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.

Classification of internal carotid artery injuries during endoscopic endonasal approaches to the skull base

Background:

Internal carotid artery (ICA) injuries are a major complication of endoscopic endonasal approaches (EEAs), which can be difficult to manage. Adding to the management difficulty is the lack of literature describing the surgical anatomical classification of these types of injuries. This article proposing a novel classification of ICA injuries during EEAs.

Methods:

The classification of ICA injuries during EEAs was generated from the review of the literature and analysis of the main author observation of ICA injuries in general. All published cases of ICA injuries during EEAs in the literature between January 1990 and January 2020 were carefully reviewed. We reviewed all patients’ demographic features, preoperative diagnoses, modes of injury, cerebral angiography results, surgical and medical management techniques, and reported functional outcomes.

Results:

There were 31 papers that reported ICA injuries during EEAs in the past three decades, most studies did not document the type of injury, and few described major laceration type of it. From that review of the literature, we classified ICA injuries into three main categories (Types I-III) and six sub-types. Type I is ICA branch injury, Type II is a penetrating injury to the ICA, and Type III is a laceration of the ICA wall. The functional neurological outcome was found to be worse with Type III and better with Type I.

Conclusion:

This is a novel classification system for ICA injuries during EEAs; it defines the patterns of injury. It could potentially lead to advancements in the management of ICA injuries in EEAs and facilitate communication to develop guidelines.

ICAR: endoscopic skull-base surgery

BACKGROUND

Endoscopic skull-base surgery (ESBS) is employed in the management of diverse skull-base pathologies. Paralleling the increased utilization of ESBS, the literature in this field has expanded rapidly. However, the rarity of these diseases, the inherent challenges of surgical studies, and the continued learning curve in ESBS have resulted in significant variability in the quality of the literature. To consolidate and critically appraise the available literature, experts in skull-base surgery have produced the International Consensus Statement on Endoscopic Skull-Base Surgery (ICAR:ESBS).

METHODS

Using previously described methodology, topics spanning the breadth of ESBS were identified and assigned a literature review, evidence-based review or evidence-based review with recommendations format. Subsequently, each topic was written and then reviewed by skull-base surgeons in both neurosurgery and otolaryngology. Following this iterative review process, the ICAR:ESBS document was synthesized and reviewed by all authors for consensus.

RESULTS

The ICAR:ESBS document addresses the role of ESBS in primary cerebrospinal fluid (CSF) rhinorrhea, intradural tumors, benign skull-base and orbital pathology, sinonasal malignancies, and clival lesions. Additionally, specific challenges in ESBS including endoscopic reconstruction and complication management were evaluated.

CONCLUSION

A critical review of the literature in ESBS demonstrates at least the equivalency of ESBS with alternative approaches in pathologies such as CSF rhinorrhea and pituitary adenoma as well as improved reconstructive techniques in reducing CSF leaks. Evidence-based recommendations are limited in other pathologies and these significant knowledge gaps call upon the skull-base community to embrace these opportunities and collaboratively address these shortcomings.

Common left carotid bifurcation at C7-Th1 level: a rare anatomical variant

The left common carotid artery usually bifurcates to the internal and external carotids at or near the superior border of thyroid cartilage. In head and neck surgery, the common carotid arteries are important landmarks, defining the plane of dissection during radical neck surgeries. According to the literature, many variations exist regarding the carotid bifurcation. Anatomical knowledge of these variants is important for surgical approaches in the head and neck regions, to avoid devastating complications that may occur, mainly during anterior neck dissections. We report an interesting case of a 75-year-old male patient with low bifurcation of the left common carotid artery, accidentally found during a routine carotid Doppler ultrasonography. Bifurcation was located at the C7-Th1 intervertebral disc height, approximately 4 cm from the aortic arch.

Sonographic Evaluation of Complications of Extracranial Carotid Artery Interventions

Carotid endarterectomy and carotid artery stenting are among the most common peripheral vascular procedures performed worldwide. Sonography is the initial and often only imaging modality used in the evaluation of iatrogenic carotid arterial injuries. This pictorial essay provides an overview of the clinical and sonographic findings of complications after interventions in the extracranial carotid arteries, including dissection, fluid collections, pseudoaneurysm, thrombosis, thromboembolism, restenosis, and stent deformation. Grayscale, color, and pulsed Doppler imaging findings are reviewed, and correlations with computed tomography, magnetic resonance imaging, and angiography are provided.

Intraoperative Common Carotid Artery Injury during Ventriculoperitoneal Shunt Surgery

There are a number of complications associated with ventriculoperitoneal shunt (VPS) surgery. The authors present a rare case of iatrogenic common carotid artery injury during VPS surgery.

Nano-hemostats and a Pilot Study of Their Use in a Large Animal Model of Major Vessel Hemorrhage in Endoscopic Skull Base Surgery

Nano-hemostats are synthetic amino acid chains that self-assemble into a scaffold under certain conditions. These have been shown to be effective in stopping bleeding in small animal models of hemorrhage. Proposed mechanisms for their effect are that they form a mesh analogous to the fibrin plug in native hemostasis and that they may potentiate both platelet activation and the coagulation cascade. These may potentially become valuable adjuncts to endoscopic skull base surgery where there is the potential for both major vessel injury and smaller perforator injury to eloquent areas where bipolar cautery may not be suitable. We present a summary of the clinical studies to date and a small pilot study of nano-hemostat in an endoscopic sheep model of major vessel hemorrhage to determine its efficacy in stopping bleeding in this potentially catastrophic complication.

Carotid Artery Injury in Anterior Cervical Spine Surgery: Multicenter Cohort Study and Literature Review

STUDY DESIGN

Retrospective study and literature review.

OBJECTIVE

To provide more comprehensive data about carotid artery injury (CAI) or cerebrovascular accident (CVA) related to anterior cervical spine surgery.

METHODS

We conducted a retrospective, multicenter, case series study involving 21 high-volume surgical centers from the AOSpine North America Clinical Research Network. Medical records of 17 625 patients who went through cervical spine surgery (levels from C2 to C7) between January 1, 2005, and December 31, 2011, were analyzed. Also, we performed a literature review using Medline and PubMed databases. The following terms were used alone, and in combination, to search for relevant articles: cervical, spine, surgery, complication, iatrogenic, carotid artery, injury, cerebrovascular accident, CVA, and carotid stenosis.

RESULTS

Among 17 625 patients that were analyzed, no cases were reported to experienced CAI or CVA after cervical spine surgery. Nevertheless, in our PubMed search we found 157 articles, but only 5 articles matched our study objective criteria; 2 cases were reported to present CAI and 3 cases presented CVA.

CONCLUSIONS

CAI and CVA related to anterior cervical spine surgeries are extremely rare. We were not able to find neither in our retrospective study nor in our literature research a correlation between the type or length of anterior cervical spine procedure with CVA or CAI complications. However, surgeons should be aware of the possibility of vascular complications and minimize intraoperative direct vascular manipulations or retraction. Preoperative screening for underlying vascular pathology and risk factors is also important.

Is C1 lateral mass screw placement safe for the Chinese, Indians, and Malays? An analysis of 180 computed tomography scans

INTRODUCTION

C1 lateral mass (C1LM) screw is a common procedure in spine surgery. However, related studies are lacking in Asia. We aim to determine the safety of C1LM screw for the Chinese, Indians, and Malays.

METHODS

Three-dimensional computed tomographies of 180 subjects (60 from each ethnic) were analyzed. The length and angulations of C1LM screw and the location of internal carotid artery (ICA) in relation to C1LM were assessed and classified according to the classification by Murakami et al. The incidence of ponticulus posticus (PP) was determined and the differences among the population of these three ethnics were recorded.

RESULTS

The average base length was 8.5 ± 1.4 mm. The lengths within the lateral mass were between 14.7 ± 1.6 mm and 21.7 ± 2.3 mm. The prevalence of PP was 8.3%. 55.3% (199) of ICA were located in zone 0, 38.3% (138) in zone 1-1, 6.4% (23) in zone 1-2, and none in zone 1-3 and zone 2. The average angulation from the entry point to the ICA was 8.5° ± 6.4° laterally. The mean distance of ICA from C1 anterior cortex was 3.7 ± 1.7 mm (range: 0.6∼11.3). There was no difference in distribution of ICA in zone 1 among the three population (Chinese-47%, Indians-61%, and Malays-53%; p > 0.05).

CONCLUSIONS

No ICA is located medial to the entry point of C1LM screw. If bicortical purchase of C1LM screw is needed, screw protrusion of less than 3 mm or medially angulated is safe for ICA. The incidence of PP is 8.3% with higher prevalence among the Indian population.

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

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

Anterior Cervical Spine Surgery for Degenerative Disease: A Review

Anterior cervical spine surgery is an established surgical intervention for cervical degenerative disease and high success rate with excellent long-term outcomes have been reported. However, indications of surgical procedures for certain conditions are still controversial and severe complications to cause neurological dysfunction or deaths may occur. This review is focused mainly on five widely performed procedures by anterior approach for cervical degenerative disease; anterior cervical discectomy, anterior cervical discectomy and fusion, anterior cervical corpectomy and fusion, anterior cervical foraminotomy, and arthroplasty. Indications, procedures, outcomes, and complications of these surgeries are discussed.

Management of carotid artery injury in endonasal surgery

Introduction Carotid artery injury (CAI) is the most feared and potentially catastrophic intraoperative complication an endoscopic skull base surgeon may face. With the advancement of transnasal endoscopic surgery and the willingness to tackle more diverse pathology, evidence-based management of this life-threatening complication is paramount for patient safety and surgeon confidence.

Objectives We review the current English literature surrounding the management of CAI during endoscopic transnasal surgery.

Data Synthesis The searched databases included PubMed, MEDLINE, Cochrane database, LILACS, and BIREME. Keywords included “sinus surgery,” “carotid injury,” “endoscopic skull base surgery,” “hemostasis,” “transsphenoidal” and “pseudoaneurysm.”

Conclusions Review of the literature found the incidence of CAI in endonasal skull base surgery to be as high as 9% in some surgeries. Furthermore, current treatment recommendations can result in damage to critical neurovascular structures. Management decisions must be made in the preoperative, operative, and postoperative setting to ensure adequate treatment of CAI and the prevention of its complications such as pseudoaneurysm. Emphasis should be placed on surgical competency, teamwork, and technical expertise through education and training.

Carotid artery injury during endoscopic endonasal skull base surgery: incidence and outcomes

BACKGROUND

Injury to the internal carotid artery (ICA) during endoscopic endonasal skull base surgery is a feared complication that is not well studied or reported.

OBJECTIVE

To evaluate the incidence, to identify potential risk factors, and to present management strategies and outcomes of ICA injury during endonasal skull base surgery at our institution.

METHODS

We performed a retrospective review of all endoscopic endonasal operations performed at our institution between 1998 and 2011 to examine potential factors predisposing to ICA injury. We also documented the perioperative management and outcomes after injury.

RESULTS

There were 7 ICA injuries encountered in 2015 endonasal skull base surgeries, giving an incidence of 0.3%. Most injuries (5 of 7) involved the left ICA, and the most common diagnosis was chondroid neoplasm (chordoma, chondrosarcoma; 3 of 7 [2% of 142 cases]). Two injuries occurred during 660 pituitary adenoma resections (0.3%). The paraclival ICA segment was the most commonly injured site (5 of 7), and transclival and transpterygoid approaches had a higher incidence of injury, although neither factor reached statistical significance. Four of 7 injured ICAs were sacrificed either intraoperatively or postoperatively. No patient suffered a stroke or neurological deficit. There were no intraoperative mortalities; 1 patient died postoperatively of cardiac ischemia. One of the 3 preserved ICAs developed a pseudoaneurysm over a mean follow-up period of 5 months that was treated endovascularly.

CONCLUSION

ICA injury during endonasal skull base surgery is an infrequent and manageable complication. Preservation of the vessel remains difficult. Chondroid tumors represent a higher risk and should be resected by surgical teams with significant experience.

Internal carotid artery dissection after anterior cervical disc replacement: first case report and literature review of vascular complications of the approach

We report the case of a 41-year-old woman who underwent cervical total disc replacement at C4C5 and C5C6 levels and fusion at C6C7 level through an anterior right-side approach. After anesthesia recovery, the patient presented left hemiparesia and facial palsy due to large right hemispheric stroke. Diffusion-weighted magnetic resonance imaging was performed as soon as the patient developed neurologic symptoms of stroke and revealed a right internal carotid artery dissection. Digital substraction angiography, endovascular stenting, angioplasty and thrombectomy were performed. Six months after treatment, clinical examination showed mild left-arm spasticity. To the best of our knowledge, only two cases of internal carotid artery stroke without dissection or thrombosis are reported. In conclusion, although vascular complications are rare after anterior cervical spine procedure, internal carotid artery dissection can occur. Suspected risk factors are prolonged retraction of the carotid artery and neck extension.

Internal carotid artery in the operative plane of endoscopic endonasal transsphenoidal surgery

The objective of this study was to measure the related parameters of intercarotid artery (ICA) in the operative plane of endonasal transsphenoidal approach for hypophyseal surgeries. Nine parameters of the ICA were examined in the computed tomographic angiographic (CTA) scan of 101 patients. The shortest distance between the middle point of the nasal columella and the projective point of the ICA (D(3)) was 85.50 (5.79) mm. The shortest distance between the anterior wall of the sphenoid sinus and the projective point of the ICA (D(4)) was 16.93 (3.50) mm. The distance between the bilateral projective points of the ICA (D(5)) was 21.60 (3.45) mm. The shortest distance from the anterior wall of the sphenoid sinus to the line between the bilateral projective points of the ICA (D(6)) was 12.1 (3.91) mm. The shortest distance between the middle point of nasal columella and the anterior wall of the sphenoid sinus (D(7)) was 72.67 (5.99) mm. The width of the angle between the bilateral ICA projective point from the middle point of the nasal columella (A(1)) was 14.9 (2.32) degrees. The width of the angle between the bilateral ICA projective points from the anterior-most point of sphenoid sinus (A(2)) was 85.49 (18.12) degrees. Clinically, it is relatively safe to work within the distances and angles measured in this research, and these results may provide information for clinical surgery of pituitary tumor.

Risk of internal carotid artery injury during C1 screw placement: analysis of 160 computed tomography angiograms

BACKGROUND CONTEXT

Injury to the internal carotid artery (ICA) is a potentially catastrophic complication of C1-lateral mass (C1-LM) or C1-C2 transarticular screw insertion.

PURPOSE

This study was designed to determine the risk of injury to the ICA during placement of these screws using computed tomography angiography (CTA).

STUDY DESIGN

Radiographic analysis using CTA.

PATIENT SAMPLE

One hundred sixty CTAs were examined, for a total of 320 ICAs.

OUTCOME MEASURES

Not applicable.

METHODS

Fine-cut intravenous CTAs with multiplanar and three-dimensional reconstruction were reviewed. The position of the ICA in relation to the anterior cortex (AC) of C1, anterior end of the anterior tubercle (AT), and medial margin of the transverse foramen (TF) was measured bilaterally in three ascending and equidistant levels of the C1-AT.

RESULTS

The position of the ICA in relation to C1 was variable. The average distance between the ICA and the AC of C1 was only 3.7 mm. Furthermore, 96% of the time the posterior margin of the ICA was located posterior to the anteriormost aspect of the anterior C1 tubercle (average distance, 5.4 mm), making the ICA vulnerable to damage if a drill, tap, or screw was inserted to the depth of the anteriormost portion of the AT as seen on a lateral fluoroscopic or radiographic view. The medial margin of the ICA was located medial to the TF (a location potentially vulnerable to injury with bicortical screw placement) less often at the caudal aspect of the C1-AT (54%) than at its middle or cranial aspect (74% and 75%, respectively). No ICAs were located anterior to the medial 30% of the C1-LM or more medially.

CONCLUSIONS

Bicortical C1-LM or C1-C2 transarticular screw placement carries a potential risk of ICA injury. Given the wide variation in ICA location relative to C1, if bicortical C1 fixation is required, preoperative CTA should be considered to determine the optimal screw trajectory. In general, inferomedially angulated C1-LM screws appear to be safer with respect to the ICA injury than other potential trajectories.

An anatomical variant : low-lying bifurcation of the common carotid artery, and its surgical implications in anterior cervical discectomy

The common carotid artery generally bifurcates into the internal and external carotid arteries at the level of C3-4. Injury to the common carotid artery during anterior cervical discectomy is a complication that is very much feared but encountered rarely. Knowing the anatomic variations of the common carotid artery and using an operating microscope during the anterior cervical approach for cases with low-lying bifurcation of the common carotid artery would prevent injuries to this artery. We present a 42-year-old female who has successfully undergone anterior cervical discectomy at the level of C5-6 and C6-7. She had a low-lying bifurcation of the common carotid artery.

Iatrogenic perforation of the internal carotid artery by a transarticular screw: An unusual case of repetitive ischemic stroke

Iatrogenic injury to the carotid artery is an uncommon but well-recognized complication of medical procedures, including cervical spine surgery. A 60-year-old man showed, over an 8-month period, evidence of recurrent cerebral infarcts in the right carotid artery territory. Repeated cardiovascular screening investigations did not lead towards an etiologic factor. Three years earlier, the patient underwent an atlantoaxial fixation procedure by means of transarticular screws because of a traumatic subluxation. An intra-arterial digital substraction angiography showed malpositioning of the fixation screw on the right side with a high grade stenotic lesion of the internal carotid artery and a pseudoaneurysm. The patient was successfully treated with endovascular stenting. Our case report illustrates the relative importance of iatrogenic carotid injury in the differential diagnosis of stroke after cervical spine surgery.

Avoidance of carotid artery injuries in transsphenoidal surgery with the Doppler probe and micro-hook blades

OBJECTIVE

Internal carotid artery (ICA) injury during sellar dural opening is a potentially catastrophic complication of transsphenoidal surgery. We describe two ICA injuries that occurred early in our endonasal transsphenoidal experience. We then describe our subsequent protocol to prevent this complication in which we use the Doppler probe for carotid localization and micro-hook blades for lateral dural opening.

METHODS

All patients undergoing endonasal tumor removal were analyzed since beginning this approach in 1998. Of 631 procedures (585 patients), three patients sustained an ICA injury.

RESULTS

In the first 114 procedures (105 patients) in which the Doppler probe was not used and hook blades were used infrequently, two (1.8%) ICA injuries occurred. In both cases, a right nostril approach was used and the left ICA was punctured on dural opening with a straight scalpel; both patients recovered without neurological sequelae. In the subsequent 517 procedures in which the Doppler probe and hook blades were used in all cases, one (0.19%) probable ICA injury occurred during an attempted removal of a cavernous sinus schwannoma, although there was no angiographic evidence of vascular injury. There were no ICA or other intracranial vascular injuries in the last 510 procedures for tumors not solely confined to the cavernous sinus.

CONCLUSION

Cavernous carotid localization with the Doppler probe before dural opening and angled hook blades for lateral dural opening can help minimize the risk of ICA injury and are recommended for all transsphenoidal operations. Because of the wider contralateral exposure provided by the endonasal approach, the ICA contralateral to the nostril of approach is at higher risk of injury on dural opening.

Inappropriate use of the title 'chiropractor' and term 'chiropractic manipulation' in the peer-reviewed biomedical literature

Background

The misuse of the title 'chiropractor' and term 'chiropractic manipulation', in relation to injury associated with cervical spine manipulation, have previously been reported in the peer-reviewed literature.

The objectives of this study were to -

1) Prospectively monitor the peer-reviewed literature for papers reporting an association between chiropractic, or chiropractic manipulation, and injury;

2) Contact lead authors of papers that report such an association in order to determine the basis upon which the title 'chiropractor' and/or term 'chiropractic manipulation' was used;

3) Document the outcome of submission of letters to the editors of journals wherein the title 'chiropractor', and/or term 'chiropractic manipulation', had been misused and resulted in the over-reporting of chiropractic induced injury.

Methods

One electronic database (PubMed) was monitored prospectively, via monthly PubMed searches, during a 12 month period (June 2003 to May 2004). Once relevant papers were located, they were reviewed. If the qualifications and/or profession of the care provider/s were not apparent, an attempt was made to confirm them via direct e-mail communication with the principal researcher of each respective paper. A letter was then sent to the editor of each involved journal.

Results

A total of twenty four different cases, spread across six separate publications, were located via the monthly PubMed searches. All twenty four cases took place in one of two European countries.

The six publications consisted of four case reports, each containing one patient, one case series, involving twenty relevant cases, and a secondary report that pertained to one of the four case reports. In each of the six publications the authors suggest the care provider was a chiropractor and that each patient received chiropractic manipulation of the cervical spine prior to developing symptoms suggestive of traumatic injury.

In two of the four case reports contact with the principal researcher revealed that the care provider was not a chiropractor, as defined by the World Federation of Chiropractic. The authors of the other two case reports did not respond to my communications. In the case series, which involved twenty relevant cases, the principal researcher conceded that the term chiropractor had been inappropriately used and that his case series did not relate to chiropractors who had undergone appropriate formal training. The author of the secondary report, a British Medical Journal editor, conceded that he had misused the title chiropractor. Letters to editors were accepted and published by all four journals to which they were sent. To date one of the four journals has published a correction.

Conclusion

The results of this year-long prospective review suggests that the words 'chiropractor' and 'chiropractic manipulation' are often used inappropriately by European biomedical researchers when reporting apparent associations between cervical spine manipulation and symptoms suggestive of traumatic injury. Furthermore, in those cases reported here, the spurious use of terminology seems to have passed through the peer-review process without correction. Additionally, these findings provide further preliminary evidence, beyond that already provided by Terrett, that the inappropriate use of the title 'chiropractor' and term 'chiropractic manipulation' may be a significant source of over-reporting of the link between the care provided by chiropractors and injury. Finally, editors of peer-reviewed journals were amenable to publishing 'letters to editors', and to a lesser extent 'corrections', when authors had inappropriately used the title 'chiropractor' and/or term 'chiropractic manipulation'.