Is magnetic anal sphincter augmentation still an option in fecal incontinence treatment: a systematic review and meta-analysis

PURPOSE

Magnetic anal sphincter (MAS) augmentation is a novel surgical option for the treatment of fecal incontinence. Current clinical evidence is conflicting. The purpose of this meta-analysis was to report the safety profile, potential benefits, and the functional efficacy of this device.

METHODS

The study followed the PRISMA guidelines. Literature databases (Medline, Scopus, Web of Science, CENTRAL) were screened for eligible articles. The primary endpoint was the pooled effect of MAS in the Cleveland Clinic Incontinence Score (CCIS) score. Quality evaluation was based on the ROBINS-I and Risk of Bias 2 tool.

RESULTS

Overall, 8 studies with 205 patients were included. MAS resulted in a significant reduction of CCIS values (p = 0.019), and improvement only in the embarrassment domain of FIQoL scores (p = 0.034). The overall morbidity rate was 61.8%. Postoperative adverse events included MAS explantation in 12%, infection in 5.1%, pain in 10% and obstructed defecation in 5.8% of patients.

CONCLUSION

The application of MAS in patients with fecal incontinence results in the improvement of some clinical parameters with a notable morbidity rate. Due to several study limitations, further, high-quality RCTs are required to delineate the efficacy and safety of MAS.

A study on the congruence and proximity of the sling and clasp fibres at the cardio-esophageal junction of the stomach

BACKGROUND AND AIM

The cardio-oesophageal sphincter that is located in close longitudinal proximity to the origin of the lesser curvature of the stomach has a unique pattern of external muscle fibres whose inner oblique layer would normally form an elongated sling and the middle partially circular layer would form a projecting clasp into the already existing muscular sling of the former congruently, which would result in the formation of an anatomical sphincter in that area that would normally be devoid of the external longitudinal muscle layer coat. Certain authors have disagreed with the notion of this standard literature and have proposed that the clasp and sling fibres need not necessarily be congruent and may even remain independent of each other with partial contributions from the longitudinal muscle layers as well that may arise tangentially in different populations, which may in turn contribute to reflux oesophagitis in that population. Hence, the clasp and sling fibre muscular patterns were observed in six formalin-embalmed cadavers at the department of anatomy in a tertiary care institute as part of routine dissections in series, and the findings were then reported.

FINDINGS

At the junction of the lesser curvature of the stomach with the oesophagus, all six cadavers showed a longitudinal sling pattern as opposed to the conventional oblique sling. The circular muscle layer was found to be merged with the outer longitudinal muscle layer to form the sling that pulled away from the clasp, resulting in a loss of congruency for the same. The clasp fibres, however, were found to be contributed by the inner oblique muscle layer. The conventional perpendicular or tangential merging of the clasp with the sling was not observed; instead, an obtuse, blunt angular merging of the clasp with the sling was observed.

DISCUSSION

The deviation of the sling from the clasp could indicate a lack of a proper fit between them at the cardio-oesophageal sphincter. The lack of robustness in the attachment of the clasp to the sling may possibly contribute to the diminished taut pull of the clasp in this subset of the population. These would be significant determinants for a predisposition to reflux oesophagitis and Barrett's oesophagus.

Robotic-assisted proctosigmoidectomy for Hirschsprung’s disease: A multicenter prospective study

BACKGROUND

Robotic surgery is a cutting-edge minimally invasive technique that overcomes many shortcomings of laparoscopic techniques, yet few studies have evaluated the use of robotic surgery to treat Hirschsprung’s disease (HSCR).

AIM

To analyze the feasibility and medium-term outcomes of robotic-assisted proctosigmoidectomy (RAPS) with sphincter- and nerve-sparing surgery in HSCR patients.

METHODS

From July 2015 to January 2022, 156 rectosigmoid HSCR patients were enrolled in this multicenter prospective study. Their sphincters and nerves were spared by dissecting the rectum completely from the pelvic cavity outside the longitudinal muscle of the rectum and then performing transanal Soave pull-through procedures. Surgical outcomes and continence function were analyzed.

RESULTS

No conversions or intraoperative complications occurred. The median age at surgery was 9.50 months, and the length of the removed bowel was 15.50 ± 5.23 cm. The total operation time, console time, and anal traction time were 155.22 ± 16.77, 58.01 ± 7.71, and 45.28 ± 8.15 min. There were 25 complications within 30 d and 48 post-30-d complications. For children aged ≥ 4 years, the bowel function score (BFS) was 17.32 ± 2.63, and 90.91% of patients showed moderate-to-good bowel function. The postoperative fecal continence (POFC) score was 10.95 ± 1.04 at 4 years of age, 11.48 ± 0.72 at 5 years of age, and 11.94 ± 0.81 at 6 years of age, showing a promising annual trend. There were no significant differences in postoperative complications, BFS, and POFC scores related to age at surgery being ≤ 3 mo or > 3 mo.

CONCLUSION

RAPS is a safe and effective alternative for treating HSCR in children of all ages; it offers the advantage of further minimizing damage to sphincters and perirectal nerves and thus providing better continence function.

Endofistula laser ablation of fistula-in-ano: a new minimally invasive technique for the treatment of fistula-in-ano

PURPOSE

Many techniques are used to treat fistula-in-ano (FIA). The major problems associated with conventional surgical techniques are postoperative complications like sepsis, incontinence, etc. Therefore, several sphincter-saving techniques have been developed in recent years including laser diodes.

METHODS

This study presents an early experience of the use of diode lasers with a capacity of 360° radial energy emission endofistula laser ablation (EFLA) of FIA to treat patients with primary low anal fistulas. The primary and secondary success rates were assessed and the factors affecting these rates were evaluated in patients (n=31) who presented with primary, uncomplicated, and low anal fistulas.

RESULTS

Out of 31 patients, 19 (61.3%) were males and 12 (38.7%) were females with a mean age of 38.6±11.5 years. Twenty-one patients (67.7%) had intersphincteric fistula, 9 (29.0%) had transsphincteric fistula, and 1 (3.2%) had suprasphincteric fistula. Thirteen patients (41.9%) had undergone some surgery in the past for FIA. Eleven patients (35.5%) developed postoperative complications. The patients had a low median pain score of 3 on the numeric pain rating scale. The primary success rate was 67.7% (21 of 31) and the secondary success rate was 80.0% (8 of 10) over a median follow-up of 2 years. A significantly higher primary healing rate was observed in patients who did not undergo any prior surgical treatments (P=0.01).

CONCLUSION

EFLA resulted in moderate primary and high secondary success rates and was not associated with major postoperative complications. Therefore, EFLA can be considered as a preferred noninvasive efficient technique for FIA treatment.

Long-term functional outcomes of artificial urinary sphincter (AMS 800™) implantation in women aged over 75 years and suffering from stress urinary incontinence caused by intrinsic sphincter deficiency

PURPOSE

To assess the outcomes after artificial urinary sphincter (AUS) implantation in older women aged over 75 years.

METHODS

A monocentric retrospective study included all non-neurological women aged over 75 years suffering from stress urinary incontinence (SUI) due to intrinsic sphincter deficiency and undergoing an AUS placement between 1991 and 2015. Early postoperative complications were reported according to Clavien-Dindo classification. Continence, defined as no pad use, was assessed at the end of follow-up. Explantation, revision and deactivation rates of the AUS were reported. A Kaplan-Meier survival curve was generated to evaluate the survival rate of the device without revision or explantation.

RESULTS

Among 393 AUS implantations, a total of 45 patients, median age 77 years (IQR 75-79), were included. Twenty-six early postoperative complications occurred in 18 patients (40%) patients. All were minor Clavien grades (I-II) except one (grade IVa). Median follow-up was 36 months (IQR 16-96). Overall, 32 women (71.1%) still had their AUS in place at the end of the follow-up, without revision or explantation. The AUS was definitively removed in four (8.9%). The AUS required revisions in nine (20%) women. The 5- and 10-year survival rates of the device without revision or explantation were 78 and 50%, respectively. Three patients (6.7%) had their AUS deactivated. At last follow-up, in an intention-to-treat analysis, the continence rate was 68.9%.

CONCLUSION

In women aged over 75-years-old, suffering from SUI, the AUS provides satisfactory functional results comparable to the general population.

Iris stromal cell nuclei deform to more elongated shapes during pharmacologically-induced miosis and mydriasis

Nuclear shape alteration in ocular tissues, which can be used as a metric for overall cell deformation, may also lead to changes in gene expression and protein synthesis that could affect the biomechanics of the tissue extracellular matrix. The biomechanics of iris tissue is of particular interest in the study of primary angle-closure glaucoma. As the first step towards understanding the mutual role of the biomechanics and deformation of the iris on the activity of its constituent stromal cells, we conducted an ex-vivo study in freshly excised porcine eyes. Iris deformation was achieved by activating the constituent smooth muscles of the iris. Pupillary responses were initiated by inducing miosis and mydriasis, and the irides were placed in a fixative, bisected, and sliced into thin sections in a nasal and temporal horizontal orientation. The tissue sections were stained with DAPI for nucleus, and z-stacks were acquired using confocal microscopy. Images were analyzed to determine the nuclear aspect ratio (NAR) using both three-dimensional (3D) reconstructions of the nuclear surfaces as well as projections of the same 3D reconstruction into flat two-dimensional (2D) shapes. We observed that regardless of the calculation method (i.e., one that employed 3D surface reconstructions versus one that employed 2D projected images) the NAR increased in both the miosis group and the mydriasis group. Three-dimensional quantifications showed that NAR increased from 2.52 ± 0.96 in control group to 2.80 ± 0.81 and 2.74 ± 0.94 in the mydriasis and miosis groups, respectively. Notwithstanding the relative convenience in calculating the NAR using the 2D projected images, the 3D reconstructions were found to generate more physiologically realistic values and, thus, can be used in the development of future computational models to study primary angle-closure glaucoma. Since the iris undergoes large deformations in response to ambient light, this study suggests that the iris stromal cells are subjected to a biomechanically active micro-environment during their in-vivo physiological function.

Assessing validity of existing fistula-in-ano classifications in a cohort of 848 operated and MRI-assessed anal fistula patients - Cohort study

Aim/background

The commonly used fistula-in-ano classifications, Park or St. James's University hospital(SJUH), neither grade fistulas as per their severity nor guide regarding their management. A new classification(NC), published in 2017, proposed to classify fistulas as per their severity and also guided in its management. The early grades (NC grade I & II) were simple fistulas and were amenable to fistulotomy whereas higher grades (NC grade III-V) were complex fistulas and were not amenable to fistulotomy.

Methods

Lower grades of all the three classifications were classified as simple (Parks: I, SJUH:I-II, NC:I-II) whereas higher grades were classified as complex (Parks: II-IV, SJUH: III-V, NC: III-V) fistulas. Fistulotomy should be possible in simple fistulas but not in complex fistulas. This was analysed for all these classifications. The long-term follow-up of continence was done by an objective scoring system (Vaizey's scores).

Results

The SJUH & Parks classifications categorized 504/828 fistulas as ‘complex’ which was quite inaccurate as 42.7%(215/504) of these fistulas were safely amenable to fistulotomy. On the other hand, the New classification (NC) classified 282/828 fistulas as ‘complex’ which was very accurate as 99% (279/282) of these were actually complex and were not amenable to fistulotomy. The change in the preoperative and the postoperative continence scores in the patients who underwent fistulotomy, as per these classifications, Parks & SJUH vs NC, was 0.064 ± 0.62 and 0.089 ± 0.85 respectively and was not significantly different(p = 0.80, Mann-Whitney U test).

Conclusions

The New classification(NC) seems better than the existing classifications for grading the disease as well as in guiding the management of the disease.

•

Largest MRI-based series of operated anal fistula patients to be ever published.

•

Analysis of 848 fistula patients to assess the validity of existing classifications.

•

Objective continence scores (Vaizey's scores) of each patient was evaluated.

•

New classification (2017) was far more accurate than Parks and SJUH classifications.

•

It accurately graded the fistulas as per their severity and guided their management.

Urethral sphincter volume and urodynamic diagnosis

AIM

To compare urethral sphincter measurements in women with different urodynamic diagnoses using three-dimensional transperineal ultrasound (TPU).

METHODS

Women with lower urinary tract dysfunction having urodynamic studies (UDS) were prospectively recruited to this study. A detailed history and vaginal examination were conducted. Saline cystometry was performed and the women were divided into groups according to their urodynamic diagnosis, which were nondiagnostic urodynamics (NUDS), pure detrusor overactivity (PureDO), pure urodynamic stress incontinence (PureUSI) and mixed urinary incontinence (MUDS). Three-dimensional TPU was performed to measure total urethral sphincter volume, striated sphincter volume, core volume, sphincter length and maximum cross-sectional area. The ultrasound measurements were compared with the diagnostic urodynamics.

RESULTS

One hundred fifty women were included in the study. There were 37, 53, 22 and 38 women in the groups of NUDS, PureDO, PureUSI and MUDS respectively. The average striated sphincter volumes in these groups were 1.84 ml, 2.24 ml, 1.32 ml and 1.98 ml respectively. There was no difference in average age, body mass index or presence of prolapse in these groups. All measurements were larger in the PureDO and smaller in the PureUSI group compared with the NUDS group. The measurements in the MUDS group were larger than in the NUDS group and smaller than in the PureDO group but this difference was not statistically significant.

CONCLUSION

The urethral sphincter of women with PureDO is larger than in women with PureUSI. The value in women with MUDS was between the two. The size of the urethral sphincter appears to be related to the pathophysiology.

Development and evolution of gut structures: from molecules to function

The emergence of a specialized system for food digestion and nutrient absorption was a crucial innovation for multicellular organisms. Digestive systems with different levels of complexity evolved in different animals, with the endoderm-derived one-way gut of most bilaterians to be the prevailing and more specialized form. While the molecular events regulating the early phases of embryonic tissue specification have been deeply investigated in animals occupying different phylogenetic positions, the mechanisms underlying gut patterning and gut-associated structures differentiation are still mostly obscure. In this review, we describe the main discoveries in gut and gut-associated structures development in echinoderm larvae (mainly for sea urchin and, when available, for sea star) and compare them with existing information in vertebrates. An impressive degree of conservation emerges when comparing the transcription factor toolkits recruited for gut cells and tissue differentiation in animals as diverse as echinoderms and vertebrates, thus suggesting that their function emerged in the deuterostome ancestor.

Generation of Spontaneous Tone by Gastrointestinal Sphincters

An important feature of the gastrointestinal (GI) muscularis externa is its ability to generate phasic contractile activity. However, in some GI regions, a more sustained contraction, referred to as "tone," also occurs. Sphincters are muscles oriented in an annular manner that raise intraluminal pressure, thereby reducing or blocking the movement of luminal contents from one compartment to another. Spontaneous tone generation is often a feature of these muscles. Four distinct smooth muscle sphincters are present in the GI tract: the lower esophageal sphincter (LES), the pyloric sphincter (PS), the ileocecal sphincter (ICS), and the internal anal sphincter (IAS). This chapter examines how tone generation contributes to the functional behavior of these sphincters. Historically, tone was attributed to contractile activity arising directly from the properties of the smooth muscle cells. However, there is increasing evidence that interstitial cells of Cajal (ICC) play a significant role in tone generation in GI muscles. Indeed, ICC are present in each of the sphincters listed above. In this chapter, we explore various mechanisms that may contribute to tone generation in sphincters including: (1) summation of asynchronous phasic activity, (2) partial tetanus, (3) window current, and (4) myofilament sensitization. Importantly, the first two mechanisms involve tone generation through summation of phasic events. Thus, the historical distinction between "phasic" versus "tonic" smooth muscles in the GI tract requires revision. As described in this chapter, it is clear that the unique functional role of each sphincter in the GI tract is accompanied by a unique combination of contractile mechanisms.

Cauda equina syndrome due to disk herniation: Long-term functional prognosis

OBJECTIVE

Cauda equina syndrome (CES) caused by lumbar disk extrusion is classically considered an indication of urgent surgery. CES can be subdivided into CESI (incomplete CES) and CESR (complete CES with urinary retention and incontinence). This paper evaluates the long-term functional outcome of a CES cohort operated on due to disk herniation.

METHODS

Single-center retrospective observational study. CES patients due to disk herniation that underwent surgery between 2000 and 2016 were included in the study. Demographic data, time intervals to diagnosis and surgery, preoperative neurologic status and outcome at the end of follow up were recorded.

RESULTS

Twenty-two patients were included (median age 44 years). Eight patients were CESR and 14 CESI. Median time from symptom onset to diagnosis was 78h (range, 12-720h), and from diagnosis to surgery 24h (range, 5-120h). Median follow up was 75 months (range, 20-195 months). At the end of follow up, in the CESR group (median time from diagnosis to surgery, 23h) only pain significantly improved after surgery (p=0.007). In the CESI group (median time from diagnosis to surgery 23h) low back pain, sciatica and urinary sphincter function significantly improved (p<0.001). There were no significant differences between early (<48h) operation (n=4) and late (n=18) in terms of sphincter recovery (Fisher's Exact Test, p=0.076).

CONCLUSION

Pain associated to CES improved both in the CESI and CESR groups. However, urinary sphincter impairment significantly improved only in the CESI group. No significant differences were found regarding long-term functional outcome between early and late surgery.

Botulinum Toxin Use in Neurourology

The use of botulinum toxin A (BTX-A) has revolutionized the treatment of neurogenic lower urinary tract dysfunction (NLUTD) over the past three decades. Initially, it was used as a sphincteric injection for detrusor sphincter dyssynergia but now is used mostly as intradetrusor injection to treat neurogenic detrusor overactivity (NDO). Its use is supported by high-level-of-evidence studies and it has become the gold-standard treatment for patients with NDO refractory to anticholinergics. Several novelties have emerged in the use of BTX-A in neurourology over the past few years. Although onabotulinumtoxinA (BOTOX^®, Allergan, Inc., Irvine, CA) remains the only BTX-A for which use is supported by large, multicenter, randomized, controlled trials (RCT), and is therefore the only one to be licensed in the United States and Europe, a second BTX-A, abobotulinumtoxinA (Dysport^®, Ipsen Biopharmaceuticals, Basking Ridge, NJ), is also supported by high-level-of-evidence studies. Other innovations in the use of BTX-A in neurourology during the past few years include the BTX switch (from abobotulinumtoxinA to onabotulinumtoxinA or the opposite) as a rescue option for primary or secondary failures of intradetrusor BTX-A injection and refinements in intradetrusor injection techniques (number of injection sites, injection into the trigone). There is also a growing interest in long-term failure of BTX-A for NDO and their management, and a possible new indication for urethral sphincter injections.

A Critical Analysis of the Current Knowledge of Surgical Anatomy of the Prostate Related to Optimisation of Cancer Control and Preservation of Continence and Erection in Candidates for Radical Prostatectomy: An Update

CONTEXT

In 2010, we published a review summarising the available literature on surgical anatomy of the prostate and adjacent structures involved in cancer control and the functional outcome of prostatectomy.

OBJECTIVE

To provide an update based on new literature to help the surgeon improve oncologic and surgical outcomes of radical prostatectomy (RP).

EVIDENCE ACQUISITION

We searched the PubMed database using the keywords radical prostatectomy, anatomy, neurovascular bundle, nerve, fascia, pelvis, sphincter, urethra, urinary continence, and erectile function. Relevant articles and textbook chapters published since the last review were critically reviewed, analysed, and summarised. Moreover, we integrated aspects that were not addressed in the last review into this update.

EVIDENCE SYNTHESIS

We found new evidence for several topics. Up to 40% of the cross-sectional surface area of the urethral sphincter tissue is laterally overlapped by the dorsal vascular complex and might be injured during en bloc ligation. Denonvilliers fascia is fused with the base of the prostate in a horizontal fashion dorsally/caudally of the seminal vesicles, requiring sharp detachment when preserved. During extended pelvic lymph node dissection, the erectile nerves are at risk in the presacral and internal iliac area. Dissection planes for nerve sparing can be graded according to the amount of tissue left on the prostate as a safety margin against positive surgical margins. Vascular structures can serve as landmarks. The urethral sphincter and its length after RP are influenced by the shape of the apex. Taking this shape into account allows preservation of additional sphincter length with improved postoperative continence.

CONCLUSIONS

This update provides additional, detailed information about the surgical anatomy of the prostate and adjacent tissues involved in RP. This anatomy remains complex and widely variable. These details facilitate surgical orientation and dissection during RP and ideally should translate into improved outcomes.

PATIENT SUMMARY

Based on recent anatomic findings regarding the prostate and its surrounding tissue, the urologist can individualise the dissection during RP according to cancer and patient characteristics to improve oncologic and functional results at the same time.

[External sphincterotomy in neurological patients: A monocentric experience]

AIM

The aim of this study was to assess the feasibility, efficacy and tolerance of Greenlight™ and Holmium sphincterotomy for treating detrusor-sphincter dyssynergia.

METHODS

All men treated with this two techniques between may 2012 and june 2015 were analyzed. Preoperative evaluation included kidney ultrasound scan, urodynamic, retrograde and voiding urethrocystography. Postoperative assessment was composed of a post-void residual volume measurement when the urethral catheter was removed and 1 year after the procedure, a retrograde and voiding urethrocystography at 3 months and telephonic Likert scale questionnaire.

RESULTS

Twelve patients were operated with Greenlight™ and 12 with Holmium. Eleven had a memocath urethral stent preoperatively. Post-void residual volume median for both techniques was 285 cc preoperatively vs 137.5 cc postoperatively (P<0.001). Likert scale global satisfaction was 75%. Five stenosis (20.8%) were observed within a median of 4 months.

CONCLUSION

Greenligth™ and Holmium procedures are efficient techniques with low morbidity. However, superiority toward monopolar incision remains to be demonstrated through complementary studies.

LEVEL OF EVIDENCE

4.

Successful Treatment of a Large Pelvic Abscess Using Intraluminal VAC: A Case Report

The most feared complication of the surgical treatment of rectal cancer is anastomotic leakage, which is related to high rates of mortality and morbidity. Here, we present a patient who could not be treated with surgical drainage but treated by intraluminal Vacuum Associated Closure (VAC). A 34-year-old male patient was treated for rectal cancer by low anterior resection, colorectal anastomosis, and diverting ileostomy following neoadjuvant CRT. The patient reported with a postoperative anastomotic disruption and a large pelvic abscess. Due to the continuation of foul-smell drainage inspite of perianal incision and drainage, intraluminal VAC was applied and the pelvic abscess and the foul-smell were successfully treated. The presence of an adequate anal sphincter tonus is a disadvantage in anastomotic leakage, since it prevents the emptying of the intestinal content and also precludes the drainage of the pelvic abscess. The endoluminal application of VAC, similar to the results of application of VAC in open wounds, has been demonstrated to decrease fibrin and necrotic tissue in the pelvic cavity and increase granulation tissue. VAC, which has long been used in the treatment of open wounds, is a promising method in the treatment of large pelvic abscesses due to anastomotic leakage following rectum resection.

A Critical Analysis of the Current Knowledge of Surgical Anatomy of the Prostate Related to Optimisation of Cancer Control and Preservation of Continence and Erection in Candidates for Radical Prostatectomy: An Update

CONTEXT

In 2010, we published a review summarising the available literature on surgical anatomy of the prostate and adjacent structures involved in cancer control and the functional outcome of prostatectomy.

OBJECTIVE

To provide an update based on new literature to help the surgeon improve oncologic and surgical outcomes of radical prostatectomy (RP).

EVIDENCE ACQUISITION

We searched the PubMed database using the keywords radical prostatectomy, anatomy, neurovascular bundle, nerve, fascia, pelvis, sphincter, urethra, urinary continence, and erectile function. Relevant articles and textbook chapters published since the last review were critically reviewed, analysed, and summarised. Moreover, we integrated aspects that were not addressed in the last review into this update.

EVIDENCE SYNTHESIS

We found new evidence for several topics. Up to 40% of the cross-sectional surface area of the urethral sphincter tissue is laterally overlapped by the dorsal vascular complex and might be injured during en bloc ligation. Denonvilliers fascia is fused with the base of the prostate in a horizontal fashion dorsally/caudally of the seminal vesicles, requiring sharp detachment when preserved. During extended pelvic lymph node dissection, the erectile nerves are at risk in the presacral and internal iliac area. Dissection planes for nerve sparing can be graded according to the amount of tissue left on the prostate as a safety margin against positive surgical margins. Vascular structures can serve as landmarks. The urethral sphincter and its length after RP are influenced by the shape of the apex. Taking this shape into account allows preservation of additional sphincter length with improved postoperative continence.

CONCLUSIONS

This update provides additional, detailed information about the surgical anatomy of the prostate and adjacent tissues involved in RP. This anatomy remains complex and widely variable. These details facilitate surgical orientation and dissection during RP and ideally should translate into improved outcomes.

PATIENT SUMMARY

Based on recent anatomic findings regarding the prostate and its surrounding tissue, the urologist can individualise the dissection during RP according to cancer and patient characteristics to improve oncologic and functional results at the same time.

Colonic wall changes in patients with diverticular disease - is there a predisposition for a complicated course?

BACKGROUND

The aim of this study was to evaluate colonic wall changes and enteric neuropathy in patients with either uncomplicated (UDD) or complicated diverticular disease (CDD). Furthermore, we evaluated the presence of an anatomic sphincter at the rectosigmoid junction (RSJ).

METHODS

Samples of colonic tissue from fifteen patients with UDD, fifteen patients with CDD and fifteen patients as control were collected. Collagen quotient I/III was measured with the Sirius-red test, expression of MMP-1, MMP-13, innervation (S100), proliferation (Ki67) and apoptosis (TUNEL) in the colonic wall were investigated by immunohistochemical studies. Furthermore, measurements of the different layers were performed to investigate the RSJ.

RESULTS

Patients with either UDD or CDD had lower collagen I/III quotients compared to the control group, significant for CDD (p = 0.007). For MMP-1 and MMP-13 only a slight increase for patients with CDD was found. The percentage of proliferating (Ki67) and apoptotic (TUNEL) cells was significantly higher for patients with CDD than in the control group (p = 0.016; p = 0.037). Upon investigating the S100-expression a significant reduce in glial cells density was found in the myenteric and mucosal plexus for both groups (UDD and CDD) compared to the control group. Measurements of the different colon layers oral, aboral and at the RSJ revealed equal values.

CONCLUSIONS

This study has shown that colonic wall changes and enteric neuropathy seem to play a role in the pathogenesis of colonic diverticulosis. None of our results suggest a predisposition for a complicated diverticular disease. Furthermore, the presence of an anatomic sphincter at the rectosigmoid junction could not be detected.

Surgical management of fecal incontinence

The surgical approach to treating fecal incontinence is complex. After optimal medical management has failed, surgery remains the best option for restoring function. Patient factors, such as prior surgery, anatomic derangements, and degree of incontinence, help inform the astute surgeon regarding the most appropriate option. Many varied approaches to surgical management are available, ranging from more conservative approaches, such as anal canal bulking agents and neuromodulation, to more aggressive approaches, including sphincter repair, anal cerclage techniques, and muscle transposition. Efficacy and morbidity of these approaches also range widely, and this article presents the data and operative considerations for these approaches.

Systematic analysis of the development of the ductus venosus in wild type mouse and human embryos

BACKGROUND

Doppler flow velocities of the ductus venosus are increasingly used to assess fetal increased nuchal translucency, growth-restriction and monochorionic twins, and might contribute to screening for cardiac defects. It is disputed whether a sphincter at the ductus venosus inlet actively regulates blood flow.

AIMS

This study aims to define the morphogenesis of the developing mouse and human ductus venosus and to address the existence of a sphincter.

STUDY DESIGN

The presence of endothelium, smooth muscle, elastic fibers and nerves in the ductus venosus of E10.5-15.5 mouse embryos and in three corresponding human embryos (CS16, CS19 and CS23) was examined using immunohistochemistry. Three-dimensional reconstructions of the ductus venosus of E11.5-15.5 mouse and CS14-23 human embryos were generated and examined.

RESULTS

The ductus venosus lumen was narrowed from ventral-caudal to dorsal-cranial in E13.5-15.5 mouse and CS16-23 human embryos. Mouse embryos showed positive endothelial Pecam1 expression from E11.5-15.5 and smooth muscle actin staining in the ventral-caudal part of the ductus venosus from E12.5-15.5. At all developmental stages, elastic fiber and nerve marker expression was not detected in the ductus venosus (Fig. 2). In human embryos endothelial Pecam1 and smooth muscle actin expression was found in the ductus venosus from CS16 and CS19 onwards. Elastic fiber and nerve marker expression was not detected in all stages (Fig. 4). Morphogenesis and staining results of the ductus venosus were similar in both species.

CONCLUSIONS

The ductus venosus lacks a sphincter at its inlet as no accumulation of smooth muscle cells, elastic fibers or nerve innervation was found in mouse embryos from E11.5-15.5 and in human embryos from CS14-23.

Regenerative medicine based applications to combat stress urinary incontinence

Stress urinary incontinence (SUI), as an isolated symptom, is not a life threatening condition. However, the fear of unexpected urine leakage contributes to a significant decline in quality of life parameters for afflicted patients. Compared to other forms of incontinence, SUI cannot be easily treated with pharmacotherapy since it is inherently an anatomic problem. Treatment options include the use of bio-injectable materials to enhance closing pressures, and the placement of slings to bolster fascial support to the urethra. However, histologic findings of degeneration in the incontinent urethral sphincter invite the use of tissues engineering strategies to regenerate structures that aid in promoting continence. In this review, we will assess the role of stem cells in restoring multiple anatomic and physiological aspects of the sphincter. In particular, mesenchymal stem cells and CD34⁺ cells have shown great promise to differentiate into muscular and vascular components, respectively. Evidence supporting the use of cytokines and growth factors such as hypoxia-inducible factor 1-alpha, vascular endothelial growth factor, basic fibroblast growth factor, hepatocyte growth factor and insulin-like growth factor further enhance the viability and direction of differentiation. Bridging the benefits of stem cells and growth factors involves the use of synthetic scaffolds like poly (1,8-octanediol-co-citrate) (POC) thin films. POC scaffolds are synthetic, elastomeric polymers that serve as substrates for cell growth, and upon degradation, release growth factors to the microenvironment in a controlled, predictable fashion. The combination of cellular, cytokine and scaffold elements aims to address the pathologic deficits to urinary incontinence, with a goal to improve patient symptoms and overall quality of life.

Is verumontanum resection needed in transurethral resection of the prostate?

Transurethral resection of the prostate is the mainstay for treatment of bladder outflow obstruction. It is a procedure that involves various complications and has a high success rate. In view of a recent publication presenting the effect of verumontanum resection on functional outcome and possible complications after TURP, the present manuscript presents the available evidence on the subject as well as the possible criticism about the technique suggested by the authors. The results available do not confirm that by resecting the verumontanum there is a clinically significant improvement in the functional outcome, however confirm that continence is not affected. The criticism probably lies in the fact that resecting such a small amount of tissue like the verumontanum (its size probably remains the same with few changes during lifetime) probably does not affect outcome, yet the resection of hyperplastic apical tissue around it may play a role in functional improvement.

New technologies in gastrointestinal research

This issue presents different new techniques aiming to increase our understanding of the gastrointestinal system and to improve treatment. The technologies cover selected methods to evoke and assess gut pain, new methods for imaging and physiological measurements, histochemistry, pharmacological modelling etc. There is no doubt that the methods will revolutionize the diagnostic approach in near future.