Pathological Findings of Donor Vessels in Bypass Surgery

(1) Background Cerebral revascularization is necessary to treat intracranial arterial stenosis caused by moyamoya disease, atherosclerosis, or large complex aneurysms. Although various donor vascular harvesting methods have been reported safe, there are no reports on the histological evaluation of donor vessels for each disease, despite the variety of diseases wherein vascular anastomosis is required. (2) Methods Pathological findings of the superficial temporal artery (STA), radial artery (RA), occipital artery (OA), and saphenous vein (SV) harvested at the institution were analyzed. Patients classified according to aneurysm, atherosclerosis, and moyamoya disease were assessed for pathological abnormalities, medical history, age, sex, smoking, and postoperative anastomosis patency. (3) Results There were 38 cases of atherosclerosis, 15 cases of moyamoya disease, and 30 cases of aneurysm in 98 donor vessels (mean age 57.2) taken after 2006. Of the 84 STA, 11 RA, 2 OA, and 1 SV arteries that were harvested, 71.4% had atherosclerosis, 11.2% had dissection, and 10.2% had inflammation. There was no significant difference in the proportion of pathological findings according to the disease. A history of hypertension is associated with atherosclerosis in donor vessels. (4) Conclusions This is the first study to histologically evaluate the pathological findings of donor vessels according to disease. The proportion of dissection findings indicative of vascular damage due to surgical manipulation was not statistically different between the different conditions.

Surgical techniques and indications for treatment of adult moyamoya disease

Moyamoya disease (MMD) is a chronic, progressive cerebrovascular disease involving the occlusion or stenosis of the terminal portion of the internal carotid artery (ICA) and the proximal anterior and middle cerebral arteries. Adults with MMD have been shown to progressively accumulate neurological and cognitive deficits without treatment, with a mortality rate double that of pediatric patients with MMD. Surgical intervention is the mainstay of treatment to prevent disease progression and improve clinical outcomes. Several different types of bypasses can be utilized for revascularization in MMD, including indirect, direct, and combined forms of extracranial-to-intracranial (EC-IC) bypass. Overall, the choice of appropriate technique requires consideration of the age of the patient, preoperative hemodynamics, neurologic status, and territories most at risk and in need of revascularization. Here, we will review the indications and surgical techniques for the treatment of adult MMD. Step-by-step instructions for performing several bypass variants with technical pearls are discussed.

Course of the V3 segment of the vertebral artery relative to the suboccipital triangle as an anatomical marker for a safe far lateral approach: A retrospective clinical study

Background:

The third segment of the vertebral artery (V3) is vulnerable during far lateral and retrosigmoid approaches. Although the suboccipital triangle (SOT) is a useful anatomical landmark, the relationship between V3 and the muscles forming the triangle is not well-described. We aimed to demonstrate the relationship between the V3, surrounding muscles, and SOT in clinical cases.

Methods:

Operative videos of patients with the vertebral artery (VA) and posterior inferior cerebellar artery (PICA) aneurysms treated with occipital artery-PICA bypass through the far lateral approach were examined. Videos from January 2015 to October 2021 were retrospectively reviewed to determine anatomy of the V3 and the SOT.

Results:

Fourteen patients were included in this study. The ipsilateral V3 was identified without injury in all patients using the bipolar cutting technique. The lateral 68.2% of the horizontal V3 segment, including the V3 bulge, was covered by the inferomedial part of the superior oblique muscle (SO). The medial 23.9% was covered by the inferolateral part of the rectus capitis posterior major muscle. The inferomedial part of the horizontal V3 segment is located within the SOT.

Conclusion:

Most of the V3, including the V3 bulge, were located beneath the SO and the inferomedial part of V3 located within the SOT. Elevation of the SO should be performed carefully using the bipolar cutting technique to avoid injury to the V3. To the best of our knowledge, this is the first description of the V3 relative to the SOT in the clinical setting.

Comparison of operative outcomes between monopolar and bipolar coagulation in hepatectomy: a propensity score-matched analysis in a single center

Background

Various hemostatic devices have been utilized to reduce blood loss during hepatectomy. Nonetheless, a comparison between monopolar and bipolar coagulation, particularly their usefulness or inferiority, has been poorly documented. The aim of this study is to reveal the characteristics of these hemostatic devices.

Methods

A total of 264 patients who underwent open hepatectomy at our institution from January 2009 to December 2018 were included. Monopolar and bipolar hemostatic devices were used in 160 (monopolar group) and 104 (bipolar group) cases, respectively. Operative outcomes and thermal damage to the resected specimens were compared between these groups using propensity score matching according to background factors. Multivariate logistic regression analysis was performed to identify predictive factors for postoperative complications.

Results

After propensity score matching, 73 patients per group were enrolled. The monopolar group had significantly lower total operative time (239 vs. 275 min; P = 0.013) and intraoperative blood loss (487 vs. 790 mL; P < 0.001). However, the incidence rates of ascites (27.4% vs. 8.2%; P = 0.002) and grade ≥ 3 intra-abdominal infection (12.3% vs. 2.7%; P = 0.028) were significantly higher in the monopolar group. Thermal damage to the resected specimens was significantly longer in the monopolar group (4.6 vs. 1.2 mm; P < 0.001). Use of monopolar hemostatic device was an independent risk factor for ascites (odds ratio, 5.626, 95% confidence interval 1.881–16.827; P = 0.002) and severe intra-abdominal infection (odds ratio, 5.905, 95% confidence interval 1.096–31.825; P = 0.039).

Conclusions

Although monopolar devices have an excellent hemostatic ability, they might damage the remnant liver. The use of monopolar devices can be one of the factors that increase the frequency of complications.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02231-y.

The Intersection Between the Sternocleidomastoid and Splenius Capitis as the Anatomical Landmark to Facilitate Occipital Artery Harvest: A Retrospective Clinical Study

BACKGROUND

Occipital artery (OA)-posterior inferior cerebellar artery (PICA) bypass is a challenging procedure and is not frequently performed owing to the difficulty of OA harvest. To facilitate harvest, the intersection between the sternocleidomastoid and splenius capitis (the OA triangle) is used as the anatomical landmark to identify the OA segment that carries the highest risk of damage. This clinical study aimed to demonstrate efficacy and safety of OA harvest using this landmark.

METHODS

The study included 18 patients who underwent OA harvest using the OA triangle as a landmark for treatment of vertebral artery and PICA aneurysms. Patients were retrospectively evaluated for safety and patency of OA after harvest and OA-PICA bypass.

RESULTS

Of 18 patients with ruptured and unruptured vertebral artery and PICA aneurysms, 13 (72.2%) underwent OA-PICA bypass and 5 (27.8%) did not undergo bypass. The OA was completely harvested without damage in all patients. After harvest, the OA was patent in 17 patients (94.4%) and was occluded in 1 patient owing to vasospasm; this patient then underwent recanalization resulting in good patency of the OA-PICA bypass. The patency rate of the OA-PICA bypass was 100%.

CONCLUSIONS

The OA triangle, which is the anatomical landmark of the proximal end of the transitional segment of the OA, facilitated OA harvest using the distal-to-proximal harvest technique with safety and good patency. To the best of our knowledge, this is the first study of OA harvest in clinical cases.

Rescue Strategy for Troublesome Situations Related to Recipient and Donor Arteries During Low-Flow Bypass Surgery

OBJECTIVE

Although technically demanding, bypass surgery is a vital part of the neurosurgical armamentarium. The aim of this article was to present representative troublesome cases related to the manipulation of donor arteries (DAs) and recipient arteries during low-flow extracranial-intracranial bypass.

METHODS

In the past 5 years, 507 low-flow bypass surgeries were performed in patients with cerebral aneurysms, moyamoya disease, and intracranial atherosclerotic stenosis. Frustrating perioperative situations were retrospectively reviewed, and 6 representative cases were described.

RESULTS

Case 1 involved repeat microanastomosis owing to occlusion of the anastomotic segment by thrombus formation. Case 2 involved repair of the DA injured by thermal energy. Case 3 involved direct repair of the DA damaged by a sharp knife. Case 4 involved repeat microanastomosis owing to avulsion of the anastomotic segment. Case 5 involved lengthening of the short DA with a nearby interposition graft. Case 6 involved use of retrograde flow via the distal segment of the DA secondary to the injury of the proximal segment of the DA. In all patients, rescue procedures were successful, and bypass flow was patent with no relevant complications.

CONCLUSIONS

The intraoperative accidents reported here were frustrating; however, all patients were safely rescued without significant sequelae. It is hoped that our experiences will help young neurosurgeons handle troublesome situations.

Dissection of the Superficial Temporal Artery: Significance and Performance with Bipolar Forceps

BACKGROUND

Adequate bypass harvesting of the superficial temporal artery (STA) is a standard procedure for every neurosurgeon, so mastery of techniques for its management and care is mandatory.

METHODS

Here, we report the effectiveness of using the bipolar forceps as a novel procedure.

RESULTS

This procedure improves safety, efficiency, and bleeding compared to the usual dissection.

CONCLUSIONS

In cases requiring an STA donor, this technique may be as useful as the traditional method and could become part of the neurosurgeon's armamentarium.

Direct double bypass using the posterior auricular artery as initial surgery for moyamoya disease: technical note

Surgical treatments for moyamoya disease (MMD) include direct revascularization procedures with proven efficacy, for example, superficial temporal artery (STA) to middle cerebral artery (MCA) bypass, STA to anterior cerebral artery bypass, occipital artery (OA) to MCA bypass, or OA to posterior cerebral artery bypass. In cases with poor development of the parietal branch of the STA, the posterior auricular artery (PAA) is often developed and can be used as the bypass donor artery. In this report, the authors describe double direct bypass performed using only the PAA as the donor in the initial surgery for MMD.In the authors' institution, MMD is routinely treated with an STA-MCA double bypass. Some patients, however, have poor STA development, and in these cases the PAA is used as the donor artery. The authors report the use of the PAA in the treatment of 4 MMD patients at their institution from 2013 to 2016. In all 4 cases, a double direct bypass was performed, with transposition of the PAA as the donor artery. Good patency was confirmed in all cases via intraoperative indocyanine green angiography and postoperative MRA or cerebral angiography. The mean blood flow measurement during surgery was 58 ml/min. No patients suffered a stroke after revascularization surgery.