Lateral Pelvic Lymph Node Metastases in Rectal Cancer: A Systematic Review.

BACKGROUND: Synchronous lateral pelvic lymph node (LPLN) involvement occurs in a significant number of patients with rectal cancer. The aim of this study is to determine the rate of LPLN metastases in rectal cancer patients with LPLN suspicious for metastases (LPLNSM) on pretreatment imaging, treated with neoadjuvant chemoradiotherapy (nCRT). Additionally, the influence of LPLN responsiveness to nCRT as determined by post-nCRT restaging scan was investigated. METHODS: A systematic review was conducted to identify studies on patients with author-defined LPLNSM that reported the pathological outcomes after total mesorectal excision (TME) with lateral pelvic lymph node dissection (LPLD). MEDLINE, EMBASE, Web of Science and the Cochrane Library were searched. The primary outcome was the percentage of pathologically confirmed LPLN metastases. RESULTS: A total of 462 patients from eleven studies were identified. The number of pathologically confirmed LPLN metastases in 361 patients that underwent uni- or bilateral LPLD ranged from 21.9 to 61.1%. The LPLD resulted in pathologically confirmed metastases in a range from 0 to 20.4% of patients with responsive LPLNSM and in a range from 25.0 to 83.3% of patients with persistent nodes. However, radiologic cutoff criteria for the evaluation of LPLN differed between studies. CONCLUSIONS: In a large number of patients with LPLNSM on initial imaging, metastatic LPLN are present after nCRT and surgical treatment. Even in LPLN that are considered responsive on restaging, significant rates of pathologically confirmed metastases are reported.

Advances in stereotactic navigation for pelvic surgery.

BACKGROUND: Stereotactic navigation could improve the quality of surgery for rectal cancer. Critical challenges related to soft tissue stereotactic pelvic navigation include the potential difference in patient anatomy between intraoperative lithotomy and preoperative supine position for imaging. The objective of this study was to determine the difference in patient anatomy, sacral tilt, and skin fiducial position between these different patient positions and to investigate the feasibility and optimal set-up for stereotactic pelvic navigation. METHODS: Four consecutive human anatomical specimens were submitted to repeated CT-scans in a supine and several degrees of lithotomy position. Patient anatomy, sacral tilt, and skin fiducial position were compared by means of an image computing platform. In two specimens, a 10-degree wedge was introduced to reduce the natural tilt of the sacrum during the shift from supine to lithotomy position. A simulation of laparoscopic and transanal surgical procedures was performed to assess the accuracy of the stereotactic navigation. RESULTS: An up-to-supracentimetric change in patient anatomy was noted between different patient positions. This observation was minimized through the application of a wedge. When switching from supine to another position, sacral retroversion occurred independent of the use of a wedge. There was considerable skin fiducial motion between different positions. Accurate stereotactic navigation was obtained with the least registration error (1.9 mm) when the position of the anatomical specimen was registered in a supine position with straight legs, without pneumoperitoneum, using a conventional CT-scan with an identical specimen positioning. CONCLUSION: The change in patient anatomy is small during the sacral tilt induced by positional changes when using a 10-degree wedge, allowing for an accurate stereotactic surgical navigation. This opens up new promising opportunities to increase the quality of surgery for rectal cancer cases where it is difficult or impossible to identify and dissect along the anatomical planes.

A step towards stereotactic navigation during pelvic surgery: 3D nerve topography.

BACKGROUND: Long-term morbidity after multimodal treatment for rectal cancer is suggested to be mainly made up by nerve-injury-related dysfunctions. Stereotactic navigation for rectal surgery was shown to be feasible and will be facilitated by highlighting structures at risk of iatrogenic damage. The aim of this study was to investigate the ability to make a 3D map of the pelvic nerves with magnetic resonance imaging (MRI). METHODS: A systematic review was performed to identify a main positional reference for each pelvic nerve and plexus. The nerves were manually delineated in 20 volunteers who were scanned with a 3-T MRI. The nerve identifiability rate and the likelihood of nerve identification correctness were determined. RESULTS: The analysis included 61 studies on pelvic nerve anatomy. A main positional reference was defined for each nerve. On MRI, the sacral nerves, the lumbosacral plexus, and the obturator nerve could be identified bilaterally in all volunteers. The sympathetic trunk could be identified in 19 of 20 volunteers bilaterally (95%). The superior hypogastric plexus, the hypogastric nerve, and the inferior hypogastric plexus could be identified bilaterally in 14 (70%), 16 (80%), and 14 (70%) of the 20 volunteers, respectively. The pudendal nerve could be identified in 17 (85%) volunteers on the right side and in 13 (65%) volunteers on the left side. The levator ani nerve could be identified in only a few volunteers. Except for the levator ani nerve, the radiologist and the anatomist agreed that the delineated nerve depicted the correct nerve in 100% of the cases. CONCLUSION: Pelvic nerves at risk of injury are usually visible on high-resolution MRI with dedicated scanning protocols. A specific knowledge of their course and its application in stereotactic navigation is suggested to improve quality of life by decreasing the likelihood of nerve injury.

Feasibility study of three-nerve-recognizing Lichtenstein procedure for inguinal hernia.

BACKGROUND: Inguinal nerve identification during open inguinal hernia repair is associated with less chronic postoperative pain. However, most Dutch surgeons do not identify all three inguinal nerves when carrying out this procedure. The aim of this study was to evaluate the feasibility of a nerve-recognizing Lichtenstein hernia repair and to measure the extra time required for surgery METHODS: Forty patients with primary inguinal hernia were operated on following the nerve-recognizing Lichtenstein hernia repair by four experienced hernia surgeons from four different Dutch teaching hospitals. The additional time needed to identify each individual nerve was recorded, and iatrogenic nerve injuries and anatomical characteristics were registered. RESULTS: Identification of the iliohypogastric and ilioinguinal nerves was each performed within 1 min. Identification of the genital branch of the genitofemoral nerve was notably more difficult but could usually be performed within 2 min. Identification of the cremasteric vein, running parallel to the genital branch, was less comprehensive. The incidence of major anatomical variations was low. Twenty-five per cent of ilioinguinal nerves, however, could not be identified. In five patients inguinal nerves were damaged iatrogenically during standard manoeuvres of the Lichtenstein hernia repair. CONCLUSION: Three-nerve-recognizing Lichtenstein hernia repair is feasible and non-time consuming if the surgeon has appropriate anatomical knowledge. In view of the low incidence of major anatomical variations, knowledge of standard inguinal nervous anatomy should be adequate. This procedure could enable the surgeon to prevent or recognize iatrogenic nerve damage and offer an opportunity to perform deliberate neurectomy as an alternative to accidental nerve injury.

[Neuralgic pain, a significant complication after a Lichtenstein procedure for inguinal hernia repair]. / Neuralgische pijn, een niet te onderschatten complicatie van een liesbreukoperatie volgens de methode van Lichtenstein.

Two male patients, aged 37 and 56, suffered from neuralgic pain after a Lichtenstein procedure for inguinal hernia repair using prosthetic reinforcement. Since mesh-based repair techniques have decreased the recurrence rate, postoperative inguinal pain has become a major complication of these operations. Three months after surgery, 20% of the patients experience some pain. In 12% of the patients this pain limits daily activities and 1-3% of the patients are invalidated by neuralgic pain. Preventing damage to sensory nerves during the operation is one way of preventing neuralgic pain. Damaged sensory nerves should be excised. Neuralgic pain after the operation may be alleviated by tricyclic antidepressants, opioids or antiepileptic drugs. In selected patients with neuralgic pain neurectomy is indicated. In one of the patients presented the neuralgic pain disappeared after neurectomy of the ilioinguinal nerve. Triple neurectomy in the other patient, however, was unsuccessful.

Surgical techniques preventing chronic pain after Lichtenstein hernia repair: state-of-the-art vs daily practice in the Netherlands.

BACKGROUND: Morbidity associated with open inguinal hernia repair (IH repair) mainly consists of chronic pain. The aim of this study was to identify possible disparities between state-of-the-art Lichtenstein repair, and its application in general practice. METHODS: A questionnaire was mailed to all surgeons and surgical residents (n = 1,374) in the Netherlands in February 2005. The objective was to determine the state of general practice with respect to technical steps during the Lichtenstein repair that are suggested to be involved in the development of chronic pain, as recently updated by Lichtenstein's successor, Amid. RESULTS: More than half of the respondents do not act according to the Lichtenstein guidelines with respect to surgical steps that are suggested to be involved with the origin of chronic pain of somatic origin. Compliance with Amid's guidelines with respect to the handling of the nerves is variable. Surgeons conducting high numbers of IH repair are more likely to operate according to the key principles of the state-of-the-art Lichtenstein repair. CONCLUSION: There is a substantial disparity between the state-of-the-art Lichtenstein repair and its application in general practice with respect to steps that are suggested to play a role in the origin of chronic groin pain.

Evaluation of new prosthetic meshes for ventral hernia repair.

BACKGROUND: In hernia repair, particularly laparoscopic hernia repair, direct contact between mesh and abdominal organs cannot always be avoided. Several mesh materials and composite meshes have been developed to decrease subsequent adhesion formation. Recently, new meshes have been introduced. In an experimental rat study, their value was established and compared with that of meshes already available on the market. METHODS: In 200 rats, eight different meshes were placed intraperitoneally and in direct contact with abdominal viscera. The following meshes were tested: polypropylene (Prolene), e-PTFE (Dualmesh), polypropylene- polyglecaprone composite (Ultrapro), titanium-polypropylene composite (Timesh), polypropylene with carboxymethylcellulose-sodium hyaluronate coating (Sepramesh), polyester with collagen-polyethylene glycol-glycerol coating (Parietex Composite), polypropylene-polydioxanone composite with oxidized cellulose coating (Proceed), and bovine pericardium (Tutomesh). At 7 and then at 30 days postoperatively, adhesion formation, mesh incorporation, tensile strength, shrinkage, and infection were scored by two independent observers. RESULTS: Parietex Composite, Sepramesh, and Tutomesh resulted in decreased surface coverage with adhesions, whereas Prolene, Dualmesh, Ultrapro, Timesh, and Proceed resulted in increased adhesion coverage. Parietex Composite, Prolene, Ultrapro, and Sepramesh resulted in the most mesh incorporation. Dualmesh and Tutomesh resulted in significantly increased shrinkage. There were no differences in mesh infection. Parietex Composite and Dualmesh resulted in a moderate inflammatory reaction, as compared with the mild reaction the other meshes exhibited. CONCLUSION: Parietex Composite and Sepramesh combine minimal adhesion formation with maximum mesh incorporation and tensile strength. The authors recommend the use of these meshes for hernia repair in which direct contact with the abdominal viscera cannot be avoided.

The role of surgical expertise with regard to chronic postoperative inguinal pain (CPIP) after Lichtenstein correction of inguinal hernia: a systematic review.

OBJECTIVE: The aim of this study was to evaluate whether a relation exists between surgical expertise and incidence of chronic postoperative inguinal pain (CPIP) after inguinal hernia repair using the Lichtenstein procedure . BACKGROUND: CPIP after inguinal hernia repair remains a major clinical problem despite many efforts to address this problem. Recently, case volume and specialisation have been found correlated to significant improvement of outcomes in other fields of surgery; to date these important factors have not been reviewed extensively enough in the context of inguinal hernia surgery. METHODS: A systematic literature review was performed to identify randomised controlled trials reporting on the incidence of CPIP after the Lichtenstein procedure and including the expertise of the surgeon. Surgical expertise was subdivided into expert and non-expert. RESULTS: In a total of 16 studies 3086 Lichtenstein procedures were included. In the expert group the incidence of CPIP varied between 6.9 and 11.7 % versus an incidence of 18.1 and 39.4 % in the non-expert group. Due to the heterogeneity between groups no statistical significance could be demonstrated. CONCLUSION: The results of this evaluation suggest that an association between surgical expertise and CPIP is highly likely warranting further analysis in a prospectively designed study.

An international consensus algorithm for management of chronic postoperative inguinal pain.

PURPOSE: Tension-free mesh repair of inguinal hernia has led to uniformly low recurrence rates. Morbidity associated with this operation is mainly related to chronic pain. No consensus guidelines exist for the management of this condition. The goal of this study is to design an expert-based algorithm for diagnostic and therapeutic management of chronic inguinal postoperative pain (CPIP). METHODS: A group of surgeons considered experts on inguinal hernia surgery was solicited to develop the algorithm. Consensus regarding each step of an algorithm proposed by the authors was sought by means of the Delphi method leading to a revised expert-based algorithm. RESULTS: With the input of 28 international experts, an algorithm for a stepwise approach for management of CPIP was created. 26 participants accepted the final algorithm as a consensus model. One participant could not agree with the final concept. One expert did not respond during the final phase. CONCLUSION: There is a need for guidelines with regard to management of CPIP. This algorithm can serve as a guide with regard to the diagnosis, management, and treatment of these patients and improve clinical outcomes. If an expectative phase of a few months has passed without any amelioration of CPIP, a multidisciplinary approach is indicated and a pain management team should be consulted. Pharmacologic, behavioral, and interventional modalities including nerve blocks are essential. If conservative measures fail and surgery is considered, triple neurectomy, correction for recurrence with or without neurectomy, and meshoma removal if indicated should be performed. Surgeons less experienced with remedial operations for CPIP should not hesitate to refer their patients to dedicated hernia surgeons.

International guidelines for prevention and management of post-operative chronic pain following inguinal hernia surgery.

PURPOSE: To provide uniform terminology and definition of post-herniorrhaphy groin chronic pain. To give guidelines to the scientific community concerning the prevention and the treatment of chronic groin and testicular pain. METHODS: A group of nine experts in hernia surgery was created in 2007. The group set up six clinical questions and continued to work on the answers, according to evidence-based literature. In 2008, an International Consensus Conference was held in Rome with the working group, with an audience of 200 participants, with a view to reaching a consensus for each question. RESULTS: A consensus was reached regarding a definition of chronic groin pain. The recommendation was to identify and preserve all three inguinal nerves during open inguinal hernia repair to reduce the risk of chronic groin pain. Likewise, elective resection of a suspected injured nerve was recommended. There was no recommendation for a procedure on the resected nerve ending and no recommendation for using glue during hernia repair. Surgical treatment (including all three nerves) should be suggested for patients who do not respond to no-surgery pain-management treatment; it is advisable to wait at least 1 year from the previous herniorraphy. CONCLUSION: The consensus reached on some open questions in the field of post-herniorrhaphy chronic pain may help to better analyze and compare studies, avoid sending erroneous messages to the scientific community, and provide some guidelines for the prevention and treatment of post-herniorraphy chronic pain.

Long-term follow-up of a randomized clinical trial of non-mesh versus mesh repair of primary inguinal hernia.

BACKGROUND: Prospective studies and meta-analyses have indicated that non-mesh repair is inferior to mesh repair based on recurrence rates in inguinal hernia. The only reliable way to evaluate recurrence rates after hernia surgery is by long-term follow-up. METHODS: Between September 1993 and January 1996, a multicentre clinical trial was performed, in which 300 patients with unilateral primary inguinal hernia were randomized to non-mesh or mesh repair. Long-term follow-up was carried out from June 2005 to January 2006. RESULTS: Median follow-up was 128 months for non-mesh and 129 months for mesh repair. The 10-year cumulative hernia recurrence rates were 17 and 1 per cent respectively (P = 0.005). Half of the recurrences developed after 3 years' follow-up. There was no significant correlation between hernia recurrence and age, level of expertise of the surgeon, contralateral hernia, obesity, history of pulmonary disease, constipation or prostate disease. CONCLUSION: After 10 years mesh repair is still superior to non-mesh hernia repair. Recurrence rates may be underestimated as recurrences continue to develop for up to 10 years after surgery.

Nerve management during open hernia repair.

BACKGROUND: Peroperative identification and subsequent division or preservation of the inguinal nerves during open hernia repair may influence the incidence of chronic postoperative pain. METHODS: A systematic literature review was performed to identify studies investigating the influence of different types of nerve management. RESULTS: Based on three randomized studies the pooled mean percentage of patients with chronic pain after identification and division of the ilioinguinal nerve was similar to that after identification and preservation of the ilioinguinal nerve. Two cohort studies suggested that the incidence of chronic pain was significantly lower after identification of all inguinal nerves compared with no identification of any nerve. Another cohort study reported a significant difference in the incidence of chronic pain in favour of identification and facultative pragmatic division of the genital branch of the genitofemoral nerve compared with no identification at all. CONCLUSION: The nerves should probably be identified during open hernia repair. Division of and preservation of the ilioinguinal nerve show similar results.

Nerve-identifying inguinal hernia repair: a surgical anatomical study.

BACKGROUND: Pain syndromes of somatic and neuropathic origin are considered to be the main causes of chronic pain after open inguinal hernia repair. Nerve-identification during open hernia repair is suggested to be associated with less postoperative chronic pain. The aim of this study was to define clinically relevant surgical anatomical zones facilitating efficient identification of the three inguinal nerves during open herniorrhaphy. METHOD: Through dissection of 18 inguinal areas of embalmed and unembalmed human cadavers, identification zones were developed for the inguinal nerves (in particular for the genital branch of the genitofemoral nerve). RESULTS: The iliohypogastric nerve was identifiable running approximately horizontally and ventrally to the internal oblique muscle perforating the external oblique aponeurosis at a mean of 3.8 cm (range 2.5-5.5 cm) cranially from the external ring. When present, the ilioinguinal nerve was identifiable running ventrally and parallel to the spermatic cord, dorsally from the aponeurosis of the external oblique muscle. Identification of the genital branch of the genitofemoral nerve was more comprehensive. The course of the genital branch is laterocaudal at the level of the internal inguinal ring. CONCLUSION: Based on the newly defined identification zones, peroperative identification of all inguinal nerves is possible. Further research is warranted to assess clinical feasibility of these zones and to evaluate the influence of (facultative) division, preservation or omittance of the identification of inguinal nerves on the incidence of chronic pain.