Prospective Evaluation of the Defecatory Functional Results in Patients Following Aorto-Aortic Reconstruction Surgery for an Abdominal Aortic Aneurysm

Pilot Study on Feasibility and Outcome of a Nerve-Preserving Aortoiliac Exposure Technique

BACKGROUND

Dysfunctional ejaculation is a common complication following open aortoiliac aneurysm surgery. It may occur in 49-63% of patients and is caused by iatrogenic damage to the sympathetic lumbar splanchnic nerves and superior hypogastric plexus. A nerve-preserving operative technique based on a unilateral right-sided approach to the abdominal aorta, was implemented in clinical practice. The aim of this pilot study was to establish the safety and feasibility of the technique, and whether a sympathetic pathway and ejaculatory function was preserved.

METHODS

Patients were asked to fill out questionnaires preoperatively, and 6 weeks, 6 months, and 9 months postoperatively. The International Index of Erectile Function, Cleveland Clinic Incontinence Score (CCIS), Patient assessment of constipation symptoms (Pac-Sym), and International Consultation on Incontinence Questionnaire on male lower urinary tract symptoms were used. Surgeons were asked to complete a technical feasibility questionnaire.

RESULTS

Twenty-four patients undergoing aortoiliac aneurysm surgery were included. The nerve-sparing phase of the procedure added an average of 5-10 min of operating time and was technically feasible in twenty-two patients. No major complications occurred during nerve-sparing exposure. Fifteen of twenty-four patients were sexually active at some point throughout the study. No postoperative loss of ejaculation was seen in sexually active patients. CCIS, Pac-sym, International Index of Erectile Function, and Incontinence Questionnaire on male lower urinary tract symptoms scores remained similar throughout the study.

CONCLUSIONS

Nerve-preserving aortoiliac reconstruction surgery is safe and feasible. Ejaculatory function is preserved. Given the low number of patients in the study, further research is needed to provide robust data.

The lumbar autonomic nerves in males: a few anatomical insights into anterior lumbar interbody fusion

BACKGROUND CONTEXT

Lumbar autonomic nerve injury is an underappreciated complication of anterior lumbar spinal surgery. A detailed description of lumbar autonomic nerve anatomy would be helpful for surgeons to minimize the risk of this complication.

PURPOSE

This study was designed to investigate the anatomical characteristics of lumbar autonomic nerves and provide a better understanding of these nerves for anterior lumbar spinal surgery.

STUDY DESIGN

A dissection-based study of 10 embalmed male cadavers.

METHODS

The lumbar autonomic nerves from 10 embalmed male cadavers were dissected in this study. The position of the lumbar sympathetic trunks was recorded. Distance between the initial sites of the lumbar splanchnic nerves (LSNs) and the corresponding lumbar vertebral inferior endplate, distance between the ipsilateral and adjacent LSNs, angles formed by the LSNs and the vertical axis were measured. This study has been supported by grants from Science and Technology Planning Project of Guangdong Province (CN) (Grant No. 2017B020210010) without potential conflict of interest-associated biases in the text of the paper.

RESULTS

In this study, a total of 72 LSNs were identified in the 10 human cadavers. On average, the investigation found that the initial sites of the first, second, third, and fourth LSNs were 9 mm distal, 5 mm distal, 9 mm proximal, and 9 mm distal to the inferior endplates of the L1, L2, L3, and L4 vertebrae, respectively, with variations from 6 to 11 mm for each nerve among specimens. There was no significant difference in the angle between each lumbar splanchnic nerve and the vertical axis (H=2.461, p=.482), with an angle of approximately 50°±6°. The distance between the first and the second LSNs, the second and the third LSNs, or the third and the fourth LSNs were 24±6 mm, 22±8 mm, and 55±11 mm, respectively. The bilateral lumbar sympathetic trunks (N=57, 95%) were more likely to be located in the first third of the sagittal plane at the level of the L2/3, L3/4, and L4/5 intervertebral discs.

CONCLUSIONS

The study found the same number and parallel courses of LSNs on each side, and on both the left and right side, the distance between the third and the fourth LSNs was much larger than the distance between the other two adjacent LSNs. The initial sites of 80.6% (n=58) of LSNs were superior to the inferior endplate of the L3 vertebra. Improved knowledge of lumbar autonomic nerve anatomy may be of great significance in reducing complications and improving surgical safety.

New insights in the neuroanatomy of the human adult superior hypogastric plexus and hypogastric nerves

BACKGROUND

The superior hypogastric plexus (SHP) is an autonomic plexus, located ventrally to the abdominal aorta and its bifurcation, innervating pelvic viscera. It is classically described as being composed of merely sympathetic fibres. However, post-operative complications after surgery damaging the peri-aortic retroperitoneal compartment suggest the existence of parasympathetic fibres. This immunohistochemical study describes the neuroanatomical composition of the human mature SHP.

MATERIAL AND METHODS

Eight pre-determined retroperitoneal localizations including the lumbar splanchnic nerves, the SHP and the HN were studied in four human cadavers. Control tissues (white rami, grey rami, vagus nerve, splanchnic nerves, sympathetic ganglia, sympathetic chain and spinal nerve) were collected to verify the results. All tissues were stained with haematoxylin and eosin and antibodies S100, tyrosine hydroxylase (TH), vasoactive intestinal peptide (VIP) and myelin basic protein (MBP) to identify pre- and postganglionic parasympathetic and sympathetic nerve fibres.

RESULTS

All tissues comprising the SHP and hypogastric nerves (HN) showed isolated expression of TH, VIP and MBP, revealing the presence of three types of fibres: postganglionic adrenergic sympathetic fibres marked by TH, unmyelinated VIP-positive fibres and myelinated preganglionic fibres marked by MBP. Analysis of control tissues confirmed that TH, VIP and MBP were well usable to interpret the neurochemical composition of the SHP and HN.

CONCLUSION

The human SHP and HN contain sympathetic and most likely postganglionic parasympathetic fibres. The origin of these fibres is still to be elucidated, however surgical damage in the peri-aortic retroperitoneal compartment may cause pelvic organ dysfunction related to both parasympathetic and sympathetic denervation.