A computed tomography study investigating the effects of botulinum toxin injections prior to complex abdominal wall reconstruction

Preoperative Botulinum Toxin A (BTA) injection in abdominal wall reconstruction for subxiphoid (M1) hernias

INTRODUCTION

Preoperative BTA assists with fascial closure during abdominal wall reconstruction. Its efficacy in subxiphoid (M1) hernias has been questioned with high rates of component separation techniques (CST) despite BTA. To assess the role of BTA in these hernias, we compared fascial closure and recurrence rates in patients with M1 hernias requiring CST with or without preoperative BTA.

METHODS

A prospectively maintained database at a tertiary hernia center was reviewed for M1 hernias who underwent CST, and grouped based on use of preoperative BTA. Standard univariate analysis was performed.

RESULTS

Of 67 patients, 30 (44.8%) received preoperative BTA. BTA versus non-BTA groups had similar mean ages (56.0 ± 14.1vs.61.5 ± 11.8 years, p = 0.087), ASA score (p = 0.345), rate of diabetes (p = 0.421), and very large defect size (499.2 ± 185.5vs.416.1 ± 238.6 cm2,p = 0.144). In the BTA group, BMI was lower (28.9 ± 5.1vs.32.7 ± 7.2 kg/m2,p = 0.018), with fewer current smokers (0%vs.10.8%,p = 0.006), and more contaminated (20.0%vs.5.4%) and dirty cases (33.3%vs.13.5%) (p = 0.008). External oblique release was performed in 24 (80.0%) BTA patients versus 23 (62.2%) non-BTA (p = 0.179), posterior CST in 6 (20.0%) versus 14 (37.8%) (p = 0.133). Rates of bilateral CST (90.0%vs.94.6% p = 0.394), fascial closure (90.0%vs.94.6%,p = 0.650), overall wound complications (33.3%vs.43.2%,p = 0.458), and recurrence (6.7%vs.2.7%,p = 0.583) were similar with average follow up of 12.7 ± 18.8 versus 24.1 ± 28.2 months (p = 0.062).

CONCLUSION

Repair of very large M1 hernias requires high rates of CST despite preoperative BTA injection. When CST is needed, BTA as a preoperative adjunct does not appear to offer benefit in terms of fascial closure rates, frequency of bilateral CST, or risk of recurrence.

Does sarcopenia have a negative impact on the efficacy of botulinum toxin A in the prehabilitation of patients undergoing incisional hernia repair? A multicentric retrospective study

BACKGROUND

Botulinum toxin A (BTA) injections are increasingly used to prepare patients undergoing surgery for incisional hernias larger than 10 cm. The aim of this study was to analyze the impact of sarcopenia on the efficacy of BTA injection in lengthening the lateral abdominal muscles.

METHODS

Between August 2018 and January 2024, patients with midline incisional hernias ≥ 10 cm undergoing preoperative BTA injections were included in a multicentric database. Sarcopenia was evaluated calculating the muscle area measured on a transverse CT scan at the level of the L3 lumbar vertebra. Muscle characteristics and the volumes of the incisional hernia and abdominal cavity were compared before and 4 to 6 weeks after BTA injection. The effect of BTA on muscle elongation was evaluated according to sarcopenia.

RESULTS

Fifty-nine patients were included. Sarcopenia did not impair the efficacy of BTA in terms of length of the lateral abdominal wall muscles, with a 1.8 cm increase bilaterally in each group. Regarding the efficacy of BTA injection, 80% of patients experienced elongation of the lateral abdominal wall muscles. Failure of the injection therefore affected 20% of patients. These results were similar in both groups, regardless of sarcopenia. Analysis of the characteristics of 'responders' and 'nonresponders' revealed that 'nonresponders' had a greater length of the lateral abdominal wall muscles on the scan prior to BTA injection, likely due to less significant muscle retraction.

CONCLUSION

Sarcopenia did not impair the effectiveness of BTA in terms of elongation prior to incisional hernia repair.

The effect of preoperative botulinum toxin a injection on traction force during hernia repair: a prospective, single-blind study, intra-patient comparison using contralateral side as a control

PURPOSE

Ventral hernias are a common complication of laparotomy, posing challenges particularly when primary fascial closure is unattainable. Although chemical component separation using preoperative botulinum toxin A (BTX) injections has emerged as a promising adjunct, objective evidence of its efficacy remains limited. This study aimed to objectively assess the effect of preoperative BTX on traction force during ventral hernia repair.

METHODS

A prospective, single-blind study was conducted on patients with midline incisional hernias following liver transplantation. BTX was administered unilaterally, and the traction force required to medially advance the anterior rectus sheath was measured intraoperatively. Pre- and post-injection CT scans were analyzed for changes in hernia size and LAW muscle measurements. Statistical analyses were performed to evaluate traction force differences between BTX-injected and uninjected sides.

RESULTS

Ten patients underwent hernia repair with primary fascial closure achieved in all cases. Comparison of pre- and post-injection CT scans showed no significant changes in hernia size. LAW muscle length increased by 1.8 cm, while thickness decreased by 0.2 cm. Intraoperative traction force measurements revealed a significant reduction on the BTX-injected side compared to the uninjected side (p < 0.0001). The traction force ratio on the BTX-injected to the uninjected side averaged 57%, indicating the efficacy of BTX in reducing tension.

CONCLUSION

Preoperative BTX significantly reduces traction force during ventral hernia repair, highlighting its potential as an adjunctive therapy in complex cases. While challenges remain in patient selection and outcome assessment, BTX offers a promising avenue for enhancing abdominal wall reconstruction outcomes and reducing surgical complications.

Prevention of component separation in complex abdominal wall surgery by Botox prehabilitation: a propensity-matched study

AIM

To facilitate midline fascial closure in complex abdominal wall surgery, component separation techniques (CST) are usually required. However, CST is associated with an enlarged morbidity. Prehabilitation could increase the compliance of the abdominal wall and thereby decrease the necessity of myofascial release. This can be accomplished by administration of botulinum toxin type A (BTA) in the lateral abdominal wall musculature. The aim of this study was to determine the effect of BTA on the subsequent necessity to perform CST in patients with complex abdominal wall hernias.

METHODS

Patients with a complex abdominal wall hernia, planned to undergo CST between July 2020 and November 2022 were included. Outcome of procedures with 300U of BTA 4 (2-6) weeks prior to surgery, were retrospectively analyzed by comparison with propensity matched subjects of an historical group. Hernia width difference was assessed by CT and operative details were included.

RESULTS

A total of 13 patients with a median hernia width of 12 cm (IQR 9-14, range 24) were prehabilitated with BTA between July 2020 and November 2022. A CST was planned for all, however not required in 6/13 patients (46%) to accomplish midline fascial closure. A mean elongation of lateral abdominal wall musculature of 4.01 cm was seen in patients not requiring CST. Compared to the propensity score matched control group, a 27% reduction (p = 0.08) in the need for CST was observed.

CONCLUSION

There is a tendency for decrease of necessity for CST by preoperatively administered BTA in patients with complex abdominal wall defects. Although small, as this study used propensity matched comparison, further exploration of BTA should be encouraged.

Volumetry after botulinum toxin A: the impact on abdominal wall compliance and endotracheal pressure

PURPOSE

Botulinum toxin type A (BTA) is an adjuvant tool used in the preoperative optimization of complex hernias before abdominal wall reconstruction (AWR). This study aims to investigate changes in the abdominal cavity and hernia sac dimensions after BTA application.

METHOD

A prospective study with 27 patients with a hernia defect of ≥ 10 cm and loss of domain (LOD) ≥ 20% underwent AWR. Computed tomography (CT) measurements and volumetry before and after the application of BTA were performed. Intraoperative and postoperative outcomes were evaluated.

RESULTS

Imaging post-BTA revealed hernia width reduction of 1.9 cm (p = 0.002), lateral abdominal wall muscle elongation of 3.1 cm (p < 0.001), hernia volume reduction (HV) from 2.9 ± 0.9L to 2.4 ± 0.8L (p < 0.001), increase in abdominal cavity volume (ACV) from 9.7 ± 2.5L to 10.3L ± 2.4L (p = 0.003), and a reduction in the HV/ACV ratio from 30.2 ± 5% to 23.4 ± 6% (p < 0.001). Fascial closure was achieved in 92.6% of cases and component separation was required in 78%. The average variation in pulmonary plateau pressure was 3.53 cmH2O, and there were no postoperative respiratory failure recorded. At the 90-day follow-up, the wound morbidity rate was 25%, unplanned readmissions were 11%, and hernia recurrence 7.4%.

CONCLUSION

BTA produces measurable volumetric changes in abdominal wall and appears to facilitate fascial closure. Further studies are required to determine the role of BTA in the surgical armamentarium for complex hernia repair.

Comparison of Two Versus Three Bilateral Botulinum Toxin Injections Prior to Abdominal Wall Reconstruction

Background: Intramuscular injection of botulinum toxin A (BTA) induces a temporary muscle paralysis. In patients with a ventral hernia, preoperative injection of BTA in the muscles of the lateral abdominal wall (LAW) leads to thinning and lengthening of these muscles, making fascial closure more likely. In many hernia centres, treatment with BTA prior to abdominal wall reconstruction has therefore become standard care. However, evidence on the optimal BTA strategy is lacking. Methods: In this single-centre retrospective study, we analysed a consecutive cohort of ventral hernia patients that underwent bilateral BTA injections prior to abdominal wall reconstruction with available CT before and after BTA. We only included patients that were treated with exactly 600 units of Dysport®, diluted into 120 mL of saline, via either two- or three injections on each side into all three LAW muscle layers. The primary outcome was the change in LAW muscle length and thickness, comparing CT measures from before BTA and 4-6 weeks after the injections. Results: We analysed 67 patients; 30 had received two injections bilaterally and 37 had received three injections bilaterally. Baseline data showed no significant differences in LAW muscle thickness or length between groups. In both groups, the median LAW muscle thickness decreased with 0.5 cm (p < 0.001). The LAW muscle length increased with 0.9 cm (p = 0.001) and 1.2 cm (p < 0.001) in the two- and three bilateral injection group, respectively. The BTA-induced changes in LAW thickness and length were not significantly different between both groups (p = 0.809 and p = 0.654, respectively). Discussion: When using the exact same dosage and distribution volume of BTA in patients with a complex abdominal wall defect, two injections bilaterally in the lateral abdominal wall muscles are as effective as three injections bilaterally.