Differences and Correlations of Morphological and Hemodynamic Parameters between Anterior Circulation Bifurcation and Side-wall Aneurysms

OBJECTIVE

The objective of this research was to explore the difference and correlation of the morphological and hemodynamic features between sidewall and bifurcation aneurysms in anterior circulation arteries, utilizing computational fluid dynamics as a tool for analysis.

METHODS

In line with the designated inclusion criteria, this study covered 160 aneurysms identified in 131 patients who received treatment at Union Hospital of Tongji Medical College, Huazhong University of Science and Technology, China, from January 2021 to September 2022. Utilizing follow-up digital subtraction angiography (DSA) data, these cases were classified into two distinct groups: the sidewall aneurysm group and the bifurcation aneurysm group. Morphological and hemodynamic parameters in the immediate preoperative period were meticulously calculated and examined in both groups using a three-dimensional DSA reconstruction model.

RESULTS

No significant differences were found in the morphological or hemodynamic parameters of bifurcation aneurysms at varied locations within the anterior circulation. However, pronounced differences were identified between sidewall and bifurcation aneurysms in terms of morphological parameters such as the diameter of the parent vessel (Dvessel), inflow angle (θF), and size ratio (SR), as well as the hemodynamic parameter of inflow concentration index (ICI) (P<0.001). Notably, only the SR exhibited a significant correlation with multiple hemodynamic parameters (P<0.001), while the ICI was closely related to several morphological parameters (R>0.5, P<0.001).

CONCLUSIONS

The significant differences in certain morphological and hemodynamic parameters between sidewall and bifurcation aneurysms emphasize the importance to contemplate variances in threshold values for these parameters when evaluating the risk of rupture in anterior circulation aneurysms. Whether it is a bifurcation or sidewall aneurysm, these disparities should be considered. The morphological parameter SR has the potential to be a valuable clinical tool for promptly distinguishing the distinct rupture risks associated with sidewall and bifurcation aneurysms.

Classification and hemodynamic characteristics of delayed intracerebral hemorrhage following stent-assisted coil embolism in unruptured intracranial aneurysms

Background and objective

Stent-assisted coil (SAC) embolization is a commonly used endovascular treatment for unruptured intracranial aneurysms (UIAs) but can be associated with symptomatic delayed intracerebral hemorrhage (DICH). Our study aimed to investigate the hemodynamic risk factors contributing to DICH following SAC embolization and to establish a classification for DICH predicated on hemodynamic profiles.

Methods

This retrospective study included patients with UIAs located in the internal carotid artery (ICA) treated with SAC embolization at our institution from January 2021 to January 2022. We focused on eight patients who developed postoperative DICH and matched them with sixteen control patients without DICH. Using computational fluid dynamics, we evaluated the hemodynamic changes in distal arteries [terminal ICA, the anterior cerebral artery (ACA), and middle cerebral artery (MCA)] pre-and post-embolization. We distinguished DICH-related arteries from unrelated ones (ACA or MCA) and compared their hemodynamic alterations. An imbalance index, quantifying the differential in flow velocity changes between ACA and MCA post-embolization, was employed to gauge the flow distribution in distal arteries was used to assess distal arterial flow distribution.

Results

We identified two types of DICH based on postoperative flow alterations. In type 1, there was a significant lower in the mean velocity increase rate of the DICH-related artery compared to the unrelated artery (-47.25 ± 3.88% vs. 42.85 ± 3.03%; p < 0.001), whereas, in type 2, there was a notable higher (110.58 ± 9.42% vs. 17.60 ± 4.69%; p < 0.001). Both DICH types demonstrated a higher imbalance index than the control group, suggesting an association between altered distal arterial blood flow distribution and DICH occurrence.

Conclusion

DICH in SAC-treated UIAs can manifest as either a lower (type 1) or higher (type 2) in the rate of velocity in DICH-related arteries. An imbalance in distal arterial blood flow distribution appears to be a significant factor in DICH development.

Virtual simulation with AneuShape™ software for microcatheter shaping in intracranial aneurysm coiling: a validation study

Background

The shaping of an accurate and stable microcatheter plays a vital role in the successful embolization of intracranial aneurysms. Our study aimed to investigate the application and the role of AneuShape™ software in microcatheter shaping for intracranial aneurysm embolization.

Methods

From January 2021 to June 2022, 105 patients with single unruptured intracranial aneurysms were retrospectively analyzed with or without AneuShape™ software to assist in microcatheter shaping. The rates of microcatheter accessibility, accurate positioning, and stability for shaping were analyzed. During the operation, fluoroscopy duration, radiation dose, immediate postoperative angiography, and procedure-related complications were evaluated.

Results

Compared to the manual group, aneurysm-coiling procedures involving the AneuShape™ software exhibited superior results. The use of the software resulted in a lower rate of reshaping microcatheters (21.82 vs. 44.00%, p = 0.015) and higher rates of accessibility (81.82 vs. 58.00%, p = 0.008), better positioning (85.45 vs. 64.00%, p = 0.011), and higher stability (83.64 vs. 62.00%, p = 0.012). The software group also required more coils for both small (<7 mm) and large (≥7 mm) aneurysms compared to the manual group (3.50 ± 0.19 vs. 2.78 ± 0.11, p = 0.008 and 8.22 ± 0.36 vs. 6.00 ± 1.00, p = 0.081, respectively). In addition, the software group achieved better complete or approximately complete aneurysm obliteration (87.27 vs. 66.00%, p = 0.010) and had a lower procedure-related complication rate (3.60 vs. 12.00%, p = 0.107). Without this software, the operation had a longer intervention duration (34.31 ± 6.51 vs. 23.87 ± 6.98 min, p < 0.001) and a higher radiation dose (750.50 ± 177.81 vs. 563.53 ± 195.46 mGy, p < 0.001).

Conclusions

Software-based microcatheter shaping techniques can assist in the precise shaping of microcatheters, reduce operating time and radiation dose, improve embolization density, and facilitate more stable and efficient intracranial aneurysm embolization.

Significant association of BDNF rs6265 G>A polymorphism with susceptibility to epilepsy: a meta-analysis

INTRODUCTION

Previously published articles have suggested that BDNF rs6265 G>A polymorphism is a potential risk factor for epilepsy. However, the results were not consistent.

METHODS

We conducted a meta-analysis to explore the association between BDNF rs6265 G>A polymorphism and epilepsy risk. Four online databases were searched, and related studies were reviewed from their inception up to June 20, 2017. ORs and corresponding 95% CIs were used to calculate the associations of each genetic model. Overall, 10 case-control publications involving 9,512 subjects were included in this meta-analysis.

RESULTS

Significant associations were found between BDNF rs6265 G>A polymorphism and epilepsy (A vs G: OR=0.88, 95% CI=0.83-0.94, P<0.01, I²=0%; GA vs GG: OR=0.88, 95% CI=0.79-0.97, P=0.01, I²=0%; AA vs GG: OR=0.79, 95% CI=0.70-0.90, P<0.01, I²=0%; GA+AA vs GG: OR=0.85, 95% CI=0.77-0.94, P<0.01, I²=0%; AA vs GG+GA: OR=0.85, 95% CI=0.76-0.95, P=0.01, I²=0%). Subgroup analysis also showed similar results in an Asian population.

CONCLUSION

Our meta-analysis indicated that BDNF rs6265 G>A polymorphism might be involved in epilepsy susceptibility, especially in the Asian population.

Tissue-engineered rhesus monkey nerve grafts for the repair of long ulnar nerve defects: similar outcomes to autologous nerve grafts

Acellular nerve allografts can help preserve normal nerve structure and extracellular matrix composition. These allografts have low immunogenicity and are more readily available than autologous nerves for the repair of long-segment peripheral nerve defects. In this study, we repaired a 40-mm ulnar nerve defect in rhesus monkeys with tissue-engineered peripheral nerve, and compared the outcome with that of autograft. The graft was prepared using a chemical extract from adult rhesus monkeys and seeded with allogeneic Schwann cells. Pathomorphology, electromyogram and immunohistochemistry findings revealed the absence of palmar erosion or ulcers, and that the morphology and elasticity of the hypothenar eminence were normal 5 months postoperatively. There were no significant differences in the mean peak compound muscle action potential, the mean nerve conduction velocity, or the number of neurofilaments between the experimental and control groups. However, outcome was significantly better in the experimental group than in the blank group. These findings suggest that chemically extracted allogeneic nerve seeded with autologous Schwann cells can repair 40-mm ulnar nerve defects in the rhesus monkey. The outcomes are similar to those obtained with autologous nerve graft.

Calcium intake and hip fracture risk: a meta-analysis of prospective cohort studies

It has been suggested that the amount of calcium intake may influence hip fracture incidence. However, the results of the researches in this regard are inconsistent. We performed this meta-analysis to estimate the association between calcium intake and hip fracture risk. Prospective cohort studies on calcium intake and hip fracture risk were identified by searching databases from the period 1960 to 2014. Results from individual studies were synthetically combined using STATA 11 software. The results indicated that a total of 8 prospective cohort studies were included in our meta-analysis, involving 2,435 cases and 267,759 participants. The combined relative risk (RR) of hip fracture for highest compared with lowest amount calcium intake was 0.97 (95% confidence interval [CI]: 0.89-1.07). Little evidence of publication bias was found. In conclusion, this meta-analysis provides evidence of no association between calcium intake and hip fracture risk. However, this finding is based on only a limited number of included studies.

A Meta-Analysis for Postoperative Complications in Tibial Plafond Fracture: Open Reduction and Internal Fixation Versus Limited Internal Fixation Combined With External Fixator

The treatment of tibial plafond fractures is challenging to foot and ankle surgeons. Open reduction and internal fixation and limited internal fixation combined with an external fixator are 2 of the most commonly used methods of tibial plafond fracture repair. However, conclusions regarding the superior choice remain controversial. The present meta-analysis aimed to quantitatively compare the postoperative complications between open reduction and internal fixation and limited internal fixation combined with an external fixator for tibial plafond fractures. Nine studies with 498 fractures in 494 patients were included in the present study. The meta-analysis found no significant differences in bone healing complications (risk ratio [RR] 1.17, 95% confidence interval [CI] 0.68 to 2.01, p = .58], nonunion (RR 1.09, 95% CI 0.51 to 2.36, p = .82), malunion or delayed union (RR 1.24, 95% CI 0.57 to 2.69, p = .59), superficial (RR 1.56, 95% CI 0.43 to 5.61, p = .50) and deep (RR 1.89, 95% CI 0.62 to 5.80) infections, arthritis symptoms (RR 1.20, 95% CI 0.92 to 1.58, p = .18), or chronic osteomyelitis (RR 0.31, 95% CI 0.05 to 1.84, p = .20) between the 2 groups.

Microsurgical anatomy of dorsal root entry zone of brachial plexus

The purpose of this study was to describe microsurgical anatomy of the dorsal root entry zone (DREZ) and provide an anatomic basis for the approach of DREZ lesion in treating radiculopathy of brachial plexus avulsion injuries. We studied 100 dorsal cervical roots and DREZ/posterior horn complexes in 20 adult cadavers. At each root level the following data were recorded: widths of laminectomy, numbers of posterior rootlets, angle of the inferior rootlets with the spinal cord, and distance from posterior median sulcus to posterolateral sulcus. On cross-sectional plane, the length and width of dorsal horn and the angle between longitudinal axis of dorsal horn and sagittal plane of spinal cord were measured. The results showed that the spinal cord segment and the entry of dorsal roots from C5 to T1 were exposed clearly after laminectomy from C4 to C7. The average number of roolets of C5-T1 roots was about 7.76 and C6 has the most. From up to down, the angle from the inferior rootlet to spinal cord of C5-T1 diminished gradually. The average distance from posterior median sulcus to posterolateral sulcus was 2.95 mm. The average length, width, and angle of posterior horn were 3.47 mm, 1.346 mm, and 35.9 degrees , respectively. Our study demonstrated that the spinous process and lamina of the C4 to C7 vertebrae should be resected to expose the C5-T1 when DREZ lesions are employed to treat pain after brachial plexus avulsion. The lesion-making apparatus should be inserted at an angle of 30 degrees -40 degrees , the width of lesion should be less than 1.2 mm and the lesion depth less than 3.1 mm.

Interleukin 2 production and its relationship with T lymphocyte subsets in patients with obstructive jaundice

Sepsis remains a major risk in the high mortality and morbidity after surgery for obstructive jaundice. The reasons for the increased susceptibility to infection are unknown. This study examined interleukin 2 (IL-2) production and the lymphocyte response to PHA mitogen in 31 patients with obstructive jaundice. Among them, 18 patients were simultaneously investigated by enumeration of T lymphocyte subsets in peripheral blood with APAAP technique. The results showed that the patients had significantly decreased IL-2 production and lymphocyte response to PHA mitogen. The percentage of Leu 3a (helper/inducer T cell) in the patients was significantly lower than that in normal controls. Leu 3a/Leu 2a (suppressor/cytotoxic T cell) ratio was significantly lower in these patients. The reduction of IL-2 production correlated significantly with the suppression of lymphocyte proliferation but not with the percentage of Leu 3a cells. From these results, it may be suggested that the reduction of IL-2 production in the patients with obstructive jaundice is an important reason for the suppression of T lymphocyte proliferative response, not merely a reflection of the decrease of helper T cells.

Altered lymphocyte subsets and natural killer cells of patients with obstructive jaundice in perioperative period

Sepsis is a common and occasionally lethal complication of obstructive jaundice. The reasons for the increased susceptibility to infection are not fully understood. This study was conducted to examine lymphocyte subsets and natural killer cells of patients with obstructive jaundice in perioperative period. In these patients, when compared with normal controls, there was a significant reduction in the percentage of Leu 4 (pan T lymphocytes), Leu 3a (T helper cells) and Leu 7 (natural killer cells) before operation, and the immune suppression induced by surgical operation was more marked and persistent.