Cerebral Bypass Surgery for Internal Carotid Artery Occlusion, Complex Supraclinoid Carotid Artery Aneurysm, and Tumors: A Report of Four Cases

Vascular Repair for Iatrogenic Injury during Microsurgical Procedures: Clinical Investigation and Review of 18 Cases at a Single Institution

BACKGROUND

 Intracranial vascular injury (VI) due to surgery is a critical complication that can lead to serious neurologic deficits. To our knowledge, only a few review articles on VI during an operation have been published so far. We retrospectively investigated the type, cause, and measurement of VI during surgery at our institution.

METHODS

 Unexpected VI cases occurred in 18 of 2,228 craniotomy procedures, including 794 aneurysm clippings and 357 tumor resections. We investigated the causes and coping techniques of the VI cases, as well as their full details.

RESULTS

 There were six cases of aneurysm neck tear, one case of sylvian vein injury, and one case of superior trunk perforation during direct clipping. Regarding tumor resection procedures, nine cases of arterial injury and one case of cortical vein injury were extracted. Almost all VIs were caused by carelessness or basic manipulation mistakes. We repaired all these cases with simple placement of suture threads with or without pinch clips, flow alteration using bypass techniques, and in 16 cases no neurologic deficit or deterioration on imaging occurred; however, 3 patients were verified to have ischemic changes on postoperative imaging.

CONCLUSIONS

 Most VIs were directly caused by a simple error and carelessness of an operator or an assistant. Many of these injuries can be avoided if a basic set of rules are followed and remembered during the surgical procedure. However, the surgical procedure involves human work, and errors cannot be eradicated even upon maximum concentration levels. Neurosurgeons should be prepared for an eventual quick repair of an unexpected cerebral VI.

Arterial spin labeling for moyamoya angiopathy: A preoperative and postoperative evaluation method

Objectives

Studies have shown that arterial spin labeling (ASL) effectively replaces traditional MRI perfusion imaging for detecting cerebral blood flow (CBF) in patients with Moyamoya angiopathy (MMA). However, there are few reports on the relationship between neovascularization and cerebral perfusion in patients with MMA. The aim of this study is to investigate the effects of neovascularization on cerebral perfusion with MMA after bypass surgery.

Methods

We selected patients with MMA in the Department of Neurosurgery between September 2019 and August 2021 and enrolled them based on the inclusion and exclusion criteria. ASL imaging was used to monitor the baseline CBF level before surgery and determine the changes in cerebral vessels at postoperative 1 week and 6 months, respectively. The Alberta stroke grade, modified Rankin Scale (mRS), and digital subtraction angiography images were used to evaluate the effect of postoperative CBF status and prognosis. Ninety hemispheres from 51 patients were included in this study. There were no significant differences in the baseline data of the enrolled patients. At 1 week and 6 months post-surgery, the CBF state in the operation area was significantly changed compared with that at baseline (P < 0.05). The preoperative Alberta score (t = 2.714, P = 0.013) and preoperative mRS score (t = 6.678, P < 0.001) correlated with postoperative neovascularization.

Conclusion

ASL is an effective method for detecting CBF and plays an important role in the long-term follow-up of patients with MMA. Combined cerebral revascularization significantly improves CBF in the operation area both in the short and long terms. Patients with lower preoperative Alberta scores and higher mRS scores were more likely to benefit from combined cerebral revascularization surgery. However, regardless of the type of patient, CBF reconstruction can effectively improve prognosis.

The 'muscle wonton' repair - A case series of internal carotid artery injuries at a single Centre during its 10-year experience in endoscopic transsphenoidal pituitary surgery

INTRODUCTION

Although rare, injury to the internal carotid artery (ICA) during pituitary surgery may result in serious morbidity such as stroke or death. This case series explores a single centre's incidence and outcomes of ICA injury during endoscopic transsphenoidal pituitary surgery, discusses the current management options, and introduces the 'muscle wonton' (morcellised muscle wrapped in a single sheet of Surgicel®) as being a viable repair option.

METHODS

All patients undergoing pituitary operations from January 2010 to December 2019 at the Queen Elizabeth Hospital, Birmingham, UK were included. Primary outcome was number of internal carotid artery injuries during pituitary surgery. Secondary outcome measures included pre-operative (demographic, risk factors such as previous radiotherapy, number of previous operations, imaging available), operative (intra-operative image guidance, intra-operative doppler ultrasound, which side ICA was damaged, repair technique) and post-operative result (death, cranial nerve VI palsy, or stroke).

RESULTS

7 out of 893 patients (0.8%) were identified as having an ICA injury. Four of the injuries were left sided. Average age was 54 years old, five were male. In four of the ICA injuries intra-operative navigation imaging was used, and a further two concurrently used ultrasound doppler. Three of the seven cases resulted in permanent morbidity (stroke). There were no other consistent demographic, pre-operative, operative, or post-operative similarities. The two patients with muscle wonton repair suffered no permanent serious complication of ICA injury (i.e. death, abducens nerve palsy, stroke).

DISCUSSION

Our findings resemble the current literature, with left sided ICA injury being more common. Different methods for repairing ICA injury exist, however morcellised muscle patches have shown significant promise in animal models, and the perforated Surgicel® helps create an easy delivery method. The muscle wonton is a viable surgical option for repairing ICA injuries during pituitary surgery.

Single loop interrupted suture technique for cerebrovascular anastomosis: Technical note

The ideal suturing technique for cerebrovascular anastomosis remains a point of debate. Although simple interrupted sutures are considered to achieve higher patency, they require longer anastomosis time compared with running sutures. The authors describe a novel techniques named single loop interrupted suture to place interrupted sutures for cerebrovascular anastomosis. The single loop interrupted suture technique consists of repeatedly placing, tying and cutting a single loop between anchor stitches. A single loose loop was placed next to the anchor stitch, tied and cut, and then another loop was placed next to the knot. The loops resulted in efficiently placed interrupted sutures. This technique is employed for a range of end-to-side cerebrovascular anastomosis procedures, and is feasible in placing interrupted suture.

Endovascular stenting for rescue of a failed donor graft during superficial temporal artery to middle cerebral artery bypass surgery: case report

Direct bypass has been used to salvage failed endovascular treatment; however, little is known of the reversed role of endovascular management for failed bypass.The authors report the case of a 7-year-old patient who underwent a superficial temporal artery to middle cerebral artery (STA-MCA) bypass for treatment of a giant MCA aneurysm and describe the role of endovascular rescue in this case. Post-bypass catheter angiogram showed occlusion of the proximal extracranial STA donor with patent anastomosis, possibly due to STA dissection. A self-expanding Neuroform Atlas stent was deployed across the dissection flap, and follow-up images showed revascularization of the STA with good MCA runoff.This case demonstrates that direct extracranial-intracranial bypass failure can infrequently originate from the STA donor vessel and that superselective angiogram can be useful for identification and treatment in such cases. With more advanced endovascular techniques the tide has turned in the treatment of complex cerebrovascular cases, with this case being an early example of successful rescue stenting for endovascular management of a failed donor after STA-MCA bypass.