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sphincter muscle [keywords]
- The distribution and chemical coding of neurons supplying the sphincter of Oddi in mammals. [Journal Article]
- Pol J Vet Sci 2013; 16(4):787-96.
The major duodenal papilla (papilla of Vater) is an important structure associated with the biliary tract and, in some species, the pancreas. It usually represents a slight elevation on the intestinal mucosa where the dilated junction (ampulla of Vater) of the commmon bile duct and pancreatic duct enters the duodenum. The ampulla is surrounded by a specifically arranged muscle structure called the sphincter of Oddi (SO) which controls the flow of bile and pancreatic fluid. The function of the sphincter is regulated by a complex system that involves many hormonal and neural factors. The literature in the field contains detailed data on the morphology of the SO in a number of mammalian species. However, the comprehensive information about the anatomy and neurochemistry of the innervation of this structure is very limited. The present review article summarizes the current knowledge on the innervation of the SO in mammals. Special emphasis has been put on the localization and chemical coding of neurons contributing to this nerve supply.
- [Open coloproctectomy with ileoanal J-pouch reconstruction]. [English Abstract, Journal Article]
- Chirurg 2014 Mar; 85(3):231-5.
Coloproctectomy is a visceral surgical intervention where the complete colon and rectum are removed up to the level of the pelvic floor or pectinate line and the anal canal. As a rule the anal canal and pelvic floor musculature including the anal sphincter muscle remain intact. The ileoanal J-pouch construction has become established as treatment of choice for reconstruction of the small intestine. This article presents the approach for open coloproctectomy with ileoanal J-pouch reconstruction by means of an operation video which is available on-line.
- Levator ani muscle avulsion during childbirth: a risk prediction model. [JOURNAL ARTICLE]
- BJOG 2014 Mar 5.
To establish the incidence of levator ani muscle (LAM) avulsion in primiparous women and to develop a clinically applicable risk prediction model.Observational longitudinal cohort study.District General University Hospital, United Kingdom.Nulliparous women at 36 weeks of gestation and 3 months postpartum.Four-dimensional transperineal ultrasound was performed during both visits. Tomographic ultrasound imaging at maximum contraction was used to diagnose no, minor or major LAM avulsion. A risk model was developed using multivariable ordinal logistic regression.Incidence of LAM avulsion and its risk factors.Of 269 women with no antenatal LAM avulsion 71% (n = 191) returned postpartum. No LAM avulsion was found after caesarean section (n = 48). Following vaginal delivery the overall incidence of LAM avulsion was 21.0% (n = 30, 95% confidence interval [95% CI] 15.1-28.4). Minor and major LAM avulsion were diagnosed in 4.9% (n = 7, 95% CI 2.2-9.9) and 16.1% (n = 23, 95% CI 10.9-23.0), respectively. Risk factors were obstetric anal sphincter injuries (odds ratio [OR] 4.4, 95% CI 1.6-12.1), prolonged active second stage of labour per hour (OR 2.2, 95% CI 1.4-3.3) and forceps delivery (OR 6.6, 95% CI 2.5-17.2). A risk model and nomogram were developed to estimate a woman's individual risk: three risk factors combined revealed a 75% chance of LAM avulsion.Twenty-one percent of women sustain LAM avulsion during their first vaginal delivery. Our risk model and nomogram are novel tools to estimate individual chances of LAM avulsion. We can now target postnatal women at risk of sustaining a LAM avulsion.
- Autologous Muscle Derived Cells for Treatment of Stress Urinary Incontinence in Women. [JOURNAL ARTICLE]
- J Urol 2014 Feb 25.
To assess 12-month safety and potential efficacy of Autologous Muscle Derived Cells for Urinary Sphincter Repair (AMDC-USR; Cook MyoSite, Incorporated, Pittsburgh, PA) in women with stress urinary incontinence (SUI).Pooled data from 2 phase I/II studies with identical patient selection criteria and outcome measures were analyzed. Enrolled patients had SUI refractory to prior treatment and no symptom improvement over the past 6 months. Patients received intrasphincteric injection of 10 (n=16), 50 (n=16), 100 (n=24), or 200 x 10(6) (n=24) AMDC-USR, derived from biopsies of each patient's quadriceps femoris. The primary outcome measure was safety, determined by incidence and severity of adverse events. Potential efficacy was measured by changes in 3-day voiding diaries, 24-hour pad tests, and UDI-6 and IIQ-7 scores.A total of 80 patients underwent AMDC-USR injection; 72 patients completed diaries and pad tests at 12-month follow-up. No adverse events attributed to AMDC-USR product were reported. Higher dose groups tended to have greater percentages of patients with at least 50% reduction in stress leaks and pad weight at 12-month follow-up. All dose groups had statistically significant improvement in UDI-6 and IIQ-7 scores at 12-month follow-up compared to baseline.AMDC-USR at doses of 10, 50, 100, and 200 x 10(6) cells appears safe. Efficacy data suggest a potential dose response with a greater percentage of patients responsive to higher doses.
- Perianal implantation of bioengineered human internal anal sphincter constructs intrinsically innervated with human neural progenitor cells. [JOURNAL ARTICLE]
- Surgery 2013 Dec 27.
The internal anal sphincter (IAS) is a major contributing factor to pressure within the anal canal and is required for maintenance of rectoanal continence. IAS damage or weakening results in fecal incontinence. We have demonstrated that bioengineered, intrinsically innervated, human IAS tissue replacements possess key aspects of IAS physiology, such as the generation of spontaneous basal tone and contraction/relaxation in response to neurotransmitters. The objective of this study is to demonstrate the feasibility of implantation of bioengineered IAS constructs in the perianal region of athymic rats.Human IAS tissue constructs were bioengineered from isolated human IAS circular smooth muscle cells and human enteric neuronal progenitor cells. After maturation of the bioengineered constructs in culture, they were implanted operatively into the perianal region of athymic rats. Platelet-derived growth factor was delivered to the implanted constructs through a microosmotic pump. Implanted constructs were retrieved from the animals 4 weeks postimplantation.Animals tolerated the implantation well, and there were no early postoperative complications. Normal stooling was observed during the implantation period. At harvest, implanted constructs were adherent to the perirectal rat tissue and appeared healthy and pink. Immunohistochemical analysis revealed neovascularization. Implanted smooth muscle cells maintained contractile phenotype. Bioengineered constructs responded in vitro in a tissue chamber to neuronally evoked relaxation in response to electrical field stimulation and vasoactive intestinal peptide, indicating the preservation of neuronal networks.Our results indicate that bioengineered innervated IAS constructs can be used to augment IAS function in an animal model. This is a regenerative medicine based therapy for fecal incontinence that would directly address the dysfunction of the IAS muscle.
- Neural Mechanisms Underlying Lower Urinary Tract Dysfunction. [REVIEW]
- Korean J Urol 2014 Feb; 55(2):81-90.
This article summarizes anatomical, neurophysiological, and pharmacological studies in humans and animals to provide insights into the neural circuitry and neurotransmitter mechanisms controlling the lower urinary tract and alterations in these mechanisms in lower urinary tract dysfunction. The functions of the lower urinary tract, to store and periodically release urine, are dependent on the activity of smooth and striated muscles in the bladder, urethra, and external urethral sphincter. During urine storage, the outlet is closed and the bladder smooth muscle is quiescent. When bladder volume reaches the micturition threshold, activation of a micturition center in the dorsolateral pons (the pontine micturition center) induces a bladder contraction and a reciprocal relaxation of the urethra, leading to bladder emptying. During voiding, sacral parasympathetic (pelvic) nerves provide an excitatory input (cholinergic and purinergic) to the bladder and inhibitory input (nitrergic) to the urethra. These peripheral systems are integrated by excitatory and inhibitory regulation at the levels of the spinal cord and the brain. Therefore, injury or diseases of the nervous system, as well as disorders of the peripheral organs, can produce lower urinary tract dysfunction, leading to lower urinary tract symptoms, including both storage and voiding symptoms, and pelvic pain. Neuroplasticity underlying pathological changes in lower urinary tract function is discussed.
- Botulinum toxin for prevention of delayed gastric emptying after esophagectomy. [Journal Article]
- Asian Cardiovasc Thorac Ann 2013 Dec; 21(6):689-92.
Esophageal cancer is among the most common gastrointestinal cancers for which the main treatment is surgery. This study was undertaken to analyze the results of Botox injection in preventing gastric stasis in these patients.60 patients with esophageal cancer in the middle and lower third parts were included in our study between 2010 and 2011, and were randomly divided into two groups. In group A, 30 patients underwent pyloroplasty, and in group B, injection of botulinum toxin into the pyloric sphincter muscle was used in 30 patients.The mean age of these patients was 61 ± 10.7 years and the male/female ratio was 33:27. Isotope scans 3 weeks after surgery showed that 5 patients in group A and 3 in group B had delayed gastric emptying; there was no significant difference between the 2 groups, and the success rate of Botox injection was 90%.Considering the fact that there was no significant difference between pyloroplasty and Botox injection on gastric emptying after surgery, and given the need to use less-aggressive techniques and facilitate greater use of endoscopic methods, botulinum toxin injection may be used instead of pyloroplasty as a simple, effective, and complication-free method to prevent delayed gastric emptying.
- Treatment of Microstomia Caused by Burn With a Nasolabial Flap-An Ingenious Approach for Tugging and Fixation of the Oral Commissure. [JOURNAL ARTICLE]
- J Craniofac Surg 2014 Feb 20.
The objectives of surgical treatment for microstomia due to cicatricial contracture after burn are to obtain sufficient oral aperture, while maintaining sphincter function of the orbicularis oris muscle, and to secure favorable function for eating and conversation in addition to good oral health.The lips of the mouth have a free border, and the oral aperture, which has been enlarged by the operation, tends to be reduced, because of the actions of the orbicularis oris muscle. When the orbicularis oris muscle is resected, putting a priority on sufficient oral aperture and prevention of redevelopment of contracture, the function of the sphincter is often damaged. With the exception of those cases with deep extensive burn that damages a wide area of orbicularis oris muscle, the muscle should be preserved as expeditiously as is practical. In such cases, however, preventive measures for the redevelopment of microstomia should be established. As a postoperative adjuvant therapy, the usefulness of splint therapy has been suggested in many reports. However, a splint should be used for a long period after the surgery, and in some cases, pain is observed with therapy. When a splint is not used for an appropriate period, microstomia may redevelop. It would be ideal to take preventive measures against the redevelopment of contracture during surgery.We provided treatment with some ingenious attempts for the nasolabial flap to a patient with microstomia caused by cicatricial contracture after burn. We obtained favorable results with no postoperative use of a splint.
- Solitary rectal ulcer syndrome presenting a polypoid mass lesions in a female patien. [Journal Article]
- Turk J Gastroenterol 2013 Oct; 24(5):456-8.
To the editor, Solitary rectal ulcer syndrome (SRUS) is a rare benign disease of the rectum, which predominately affects young adults aged between 30 and 50 years with a prevalence of 1 in 100.000 people per year (1). SRUS usually presents with a symptom complex of rectal bleeding, passage of mucus and straining on defecation, tenesmus, perineal and abdominal pain, sensation of incomplete defecation, constipation and rectal prolapse (2). The underlying etiology of SRUS is not fully understood, but it is likely to be secondary to ischemic changes in the rectum associated with paradoxical contraction of the pelvic floor and external anal sphincter muscles and with rectal prolapse (3). The macroscopic appearance of the rectal lesion may vary from hyperemia to ulceration or a polypoid lesion that can mimic carcinoma (4), although the histological findings are characteristic, with fibromuscular obliteration of the lamina propria and disorientation of muscle fibers (5). We report the case of a woman who presented with a polypoid mass lesion of the rectum representing a SRUS variant. A 20-year-old female patient was referred to our gastroenterology clinic with a 2-year history of recurrent rectal bleeding. Digital rectal examination revealed an irregular broad based polypoid lesion palpated on the rectum about 8 cm from the anal verge. The laboratory findings were normal. Colonoscopy revealed multiple polypoid mass lesions in the rectum located at 5-10 cm from the anal verge with circumferential distribution. The mucosal surface of these lesions was ulcerated and covered with exudates. The surrounding mucosa was smooth with absence of the normal vascular pattern (Figure 1). The remaining colon up to the cecum was normal. Several mucosal biopsies were obtained from the lesions. Histopathological examination revealed focal ulcerations of the lining mucosa with granulation tissue formation. There was smooth muscle fiber expansion between glands up to the submucosa which was perpendicular to the glands (Figure 2A-C). The crypt architecture was maintained, with no findings of granuloma, atypia, or malignancy. In adults, 25-32% of SRUS may appear as polypoid lesions (6). The SRUS-polypoid variant may lead to serious misdiagnosis as its appearance may be confused with an inflammatory polyp, hyperplastic polyps, or rectal carcinoma (6,7). Our patient had multiple polypoid lesions that were circumferential with an ulcerated surface that mimicked rectal cancer in its appearance. In conclusion, the presence of a rectal polypoid mass with ulceration in a young adult with rectal bleeding should raise the suspicion of SRUS.
- Anal sphincter repair with muscle progenitor cell transplantation: serial assessment with iron oxide-enhanced MRI. [Journal Article]
- AJR Am J Roentgenol 2014 Mar; 202(3):619-25.