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The mycotic flora in proctological patients with and without pruritus ani.

The perianal mycotic flora was studied in proctological patients with and without pruritus ani, as well as in control subjects. Four groups of patients underwent perianal mycoculture. In Group 1, 53 patients with anal pruritus were treated for benign anorectal disease. In Group 2, 24 patients with no underlying disease presented with anal pruritus. Both of these groups underwent concomitant chemical and parasitical examination of the faeces and an oral glucose tolerance test. In Group 3, 50 patients without pruritus ani at present or in the past were treated for benign anorectal diseases. In Group 4, 47 surgical patients without pruritus ani were treated for benign (9) and malignant (38) non-proctological diseases. In Group 1 the mycoculture was positive in 24/53 patients (Candida albicans 14, dermatophytes 10). In Group 2 fungal infections were seen in 16/24 patients (C. albicans 7, dermatophytes 9). No parasites or diabetes were found in either group. In Group 3 C. albicans was isolated in 14/50 patients. In Group 4 C. albicans was found in 11/47 cases (2 in benign, 9 in malignant diseases). Infection by C. albicans was observed in all groups studied, independent of the presence of disease or anal pruritus. The presence of dermatophytes was always associated with pruritus ani.

Adolescent↗

Intradermal methylene blue injection for the treatment of intractable idiopathic pruritus ani: results of 30 cases.

Some cases of idiopathic pruritus anu may be refractory to treatment with dietary and hygienic instructions and short-term topical medications. In this study, we documented our technique and results with methylene blue injection in a large series of patients with intractable idiopathic pruritus ani. The results of 30 adult patients with well-documented intractable idiopathic pruritus ani who were treated with intradermal methylene blue injection are reported. No antibiotic prophylaxis, anesthesia or sedation was used. A total of 15 ml of a 1% methylene blue solution was injected intracutaneously and subcutaneously in the affected perianal area. A second injection (rescue treatment) was offered one month later to patients who declared partial response, and follow-up was restarted. One month after injection, 24 patients (80%) were symptom-free, 5 declared partial remissions, and one patient still had the same degree of pruritus ani. Five patients with partial remission underwent a second methylene blue injection, which provided complete relief in four. Therefore, the early response rate was 80% with single injection and 93.3% (28 of 30) with the rescue treatment. At six months, three recurrences were noted, indicating to a success rate of 83.3% (25 of 30). At 12 months after treatment, 23 patients (76.7%) were symptom free. This study has shown that intradermal methylene blue injection is a safe, simple, fast and efficient method of treating intractable idiopathic pruritus ani.

Adult↗

Treatment of persistent pruritus ani in a combined colorectal and dermatological clinic.

BACKGROUND: Pruritus ani is a common and socially embarrassing condition which is often poorly managed. It is often classified as idiopathic where the symptoms are usually transitory or secondary when a more persistent itch is experienced. The aim of this study was to establish the cause of pruritus ani in a group of patients referred to a combined colorectal and dermatological clinic, and to determine the most appropriate treatment. METHODS: Forty consecutive patients with pruritus ani were referred over a 6-month period from either the general practitioner or another hospital consultant to a combined colorectal and dermatological clinic. They were assessed by history, completion of a general health questionnaire, full examination of the skin, digital rectal examination, proctoscopy, sigmoidoscopy and patch testing. Patients were treated according to clinical findings at assessment. RESULTS: Thirty-four patients had a recognizable dermatosis, three had superficial perianal fissuring and three had a normal perineum; two required surgical intervention. Eighteen patients had a positive reaction when patch tested. All patients have shown an improvement or complete resolution of symptoms with treatment. CONCLUSION: This series has shown that the majority of patients presenting with pruritus ani have a dermatosis as the underlying cause of their symptoms and that many of them have developed contact sensitivities to the various topical medications used. These findings suggest that referral to a dermatologist in the first instance may be more appropriate.

Adolescent↗

Psychological assessment of patients with idiopathic pruritus ani.

BACKGROUND: The purpose of this study was to compare psychological profiles in 17 patients suffering from idiopathic pruritus ani with a control group of 28 patients showing secondary pruritus ani. METHODS: The two groups completed the Mini-Mult personality test and results were compared using chi 2 test and analysis of variance. RESULTS: The mean hypomania and depression scale scores were greater and smaller respectively in the idiopathic pruritus ani group. Nevertheless, the percentage of abnormal psychological profiles was not significantly different between the two groups. CONCLUSIONS: It seems arbitrary to systematically ascribe psychogenic aetiologies to idiopathic pruritus ani even though psychological factors may be present in individual patients.

Adult↗

M. levator ani in the rat: does it really lift the anus?

BACKGROUND: There is a good deal of confusion about the denomination of the pelvic floor muscles of the rat in the literature. By carefully dissecting and observing tail and visceral movements and pressure measurements in the vagina, rectum, and urethra during electrical stimulation, we studied the anatomy and function of the different muscles and searched for similarities with the human anatomy. RESULTS: We found some degree of similarity between the M. pubococcygeus and M. iliococcygeus muscles in both species. The M. levator ani in the rat resembles in gross anatomy the M. puborectalis in man, but the insertion and function are different. More specifically, stimulation of the M. levator ani led to only a negligible pressure rise in the rectum and no lifting of the rectum or anus. CONCLUSIONS: The M. pubococcygeus and the M. iliococcygeus share similarities with their homologues in the human. The M. levator ani, which is present only in the male rat, reveals some anatomical resemblance with the human M. puborectalis but has a different insertion and function. Because it does not lift the anus during contraction, its denomination as M. levator ani seems unjustified. Because of its principal sexual function, its fixation to the bulbus, and its sensitivity to testosterone, naming this muscle M. bulbocavernosus dorsalis would indeed seem more logical.

Anal Canal↗

Compliance of the bladder neck supporting structures: importance of activity pattern of levator ani muscle and content of elastic fibers of endopelvic fascia.

AIMS: Firm bladder neck support during cough, suggested to be needed for effective abdominal pressure transmission to the urethra, might depend on activity of the levator ani muscle and elasticity of endopelvic fascia. METHODS: The study group of 32 patients with stress urinary incontinence and hypermobile bladder neck, but without genitourinary prolapse, were compared with the control group of 28 continent women with stable bladder neck. The height of the bladder neck (HBN) and compliance of the bladder neck support (C) were assessed, the latter by the quotient of the bladder neck mobility during cough and the change in abdominal pressure. By using wire electrodes, the integrated full-wave rectified electromyographic (EMGave) signal of the levator ani muscle was recorded simultaneously with urethral and bladder pressures. The pressure transmission ratio (PTR), time interval between the onset of muscle activation and bladder pressure increment (DeltaT), and area under the EMGave curve during cough (EMGcough) were calculated. From bioptic samples of endopelvic fascia connecting the vaginal wall and levator ani muscle, elastic fiber content was assessed by point counting method. Mann-Whitney test was used to compare all the variables. Correlations between the parameters were evaluated by using the Spearman correlation coefficient. RESULTS: In the study group, HBN was significantly lower (P < 0.001), C was significantly greater (P < 0.001), and PTR was significantly lower (P < 0.001). In the study group, the muscular activation started later (median, DeltaT(l), -0.147 second; DeltaT(r), -0.150 second), and in the control group, it preceded (DeltaT(l), 0.025 second; P < 0.001; DeltaT(r), 0.050 second; P < 0.001) the bladder pressure increment. EMGcough on the left side was significantly greater in the study group (P < 0.046). Elastic fiber content showed no difference between the groups. The analysis of all patients revealed negative correlations between C and PTR (r = -0.546; P < 0.001) and between C and DeltaT(l) (r = -0.316; P < 0.018). CONCLUSIONS: Firm bladder neck support enables effective pressure transmission. Timely activation of the levator ani seems to be an important feature.

Adult↗

Morphologic study on levator ani muscle in patients with pelvic organ prolapse and stress urinary incontinence.

The objective of this study was to determine the morphologic changes of the levator ani muscle of patients with pelvic organ prolapse and stress urinary incontinence. Histological and histochemical analyses of the biopsy specimens of the levator ani muscle obtained from patients with stress urinary incontinence (SUI), pelvic organ prolapse (POP), and a control group were performed. The striated muscle-positive biopsy rate was 26.7% in the SUI group, 15.8% in the POP group, whereas it was 100% in the control group. The diameters of types I and II fibers decreased significantly with age and menopausal time in the control group. Splitting or fragmentation of fibers with red granules, which are called ragged-red fibers, were found in the SUI group. The diameters of levator ani muscle fibers in the control group were significantly larger than those in the SUI group (p=0.034<0.05). The degenerative change in histology and decrease in relative number of levator ani muscle might be associated with women suffering from SUI.

Adult↗

Levator ani muscle: new physioanatomical aspects and role in the micturition mechanism.

The anatomy of the levator ani muscle was studied in relation to the urinary bladder. The study was performed on 23 cadavers by dissection and microscopic examination. The levator ani is funnel-shaped and consists of a transverse portion called the levator plate and a vertical portion called the suspensory sling. The levator plate is a cone and consists of two "lateral masses" and two "crura," with the levator hiatus occupying its anterior part. Three crural patterns could be identified: classic, crural overlap, and crural scissors. The levator crura are connected to the intrahiatal organs by the hiatal ligament; the pubovesical ligament constitutes the anterior part of this ligament. The suspensory sling forms a vertical cuff around the intrahiatal organs, from which it is separated by a "tunnel septum." Its urethral portion ends in multiple fibrous septa, which penetrate the striated urethral sphincter. The levator ani plays an important role in bladder-neck fixation provided by the suspensory sling and hiatal ligament. Levator ani and hiatal ligament subluxation leads to ptosis of the urinary bladder. Furthermore, the present study demonstrates that the urethra is located in the infralevator compartment and is thus protected from the effect of intraabdominal pressure. A chronic increase in intraabdominal pressure leads to levator subluxation and sagging and to urethral exposure to intraabdominal pressure, which seems to interfere with the micturition mechanism. The infralevator location of the urethra might have a bearing on the pathogenesis and treatment of stress urinary incontinence.

Adolescent↗

Magnetic resonance imaging of the levator ani with anatomic correlation.

OBJECTIVE: To define in women the anatomy of the levator ani muscle visible on magnetic resonance imaging (MRI) so these muscles can be studied in women with prolapse or incontinence. METHODS: Multiplanar T1- and T2-weighted MRI was obtained of two female pelvic cadaver specimens, ages 25 and 33. One specimen was hemisected, with half sectioned in the axial plane and the other half in the coronal plane. The other specimen was sectioned in the coronal plane. Anatomic cross sections of these specimens were correlated with the cadaver MRI and MRI of living patients. One sagittal and two axial series of anatomic sections not imaged were also used for comparison. RESULTS: Serial sagittal and axial MRI demonstrates the pubovisceralis ("pubococcygeus") muscle as it originates from the pubic bone, passes alongside the urethra, vagina, and rectum, and then dorsal to the anorectum. Its muscle bulk, attachment to the distal half of the vagina, and insertion between the internal and external anal sphincters can be seen on axial views. The origin of the iliococcygeus muscle at the arcus tendineus levator ani is seen in axial and coronal images. Coronal and sagittal images demonstrate the relative thickness and medial position of the pubovisceralis muscle compared with the thin, diaphragm-like lateral iliococcygeus muscle. CONCLUSION: Magnetic resonance imaging of the cadaver pelvis demonstrates the detailed anatomy of the levator ani muscle. This is an important precursor to future research of the structure, bulk, and orientation of the levator ani in living women with prolapse.

Adult↗

Distribution and immunohistochemical characterization of primary afferent neurons innervating the levator ani muscle of the female squirrel monkey.

OBJECTIVE: This study was undertaken to examine the neurofilament and neurochemical composition of subpopulations of primary afferent neurons innervating the levator ani muscle by combining retrograde tracing and triple labeling immunofluorescence in the female squirrel monkey. STUDY DESIGN: Cholera toxin B subunit (CTB) was injected unilaterally into the levator ani muscle of 3 monkeys to identify primary sensory neurons in the dorsal root ganglia (DRG) and their central projections in the spinal cord. L7-S2 DRG were processed for dual or triple labeling immunofluorescence 3 days after injection to examine labeling of the 200 kD neurofilament marker RT97 (a marker of myelinated neurons), calcitonin gene-related peptide (CGRP; a marker of peptidergic neurons), isolectin B4 (IB4; a marker of small, unmyelinated neurons), and nerve growth factor receptor (TrkA) in CTB-positive neurons. RESULTS: RT97-negative (C-fiber) neurons were more numerous (74% of total CTB-labeled neurons) and smaller in size than RT97-positive (A-fiber) afferent neurons (26% of CTB-labeled neurons). IB4 labeling was almost exclusively found in RT97-negative afferent neurons. Approximately 43% of all CTB-labeled DRG neurons expressed CGRP, and the majority of these were small. The distribution and sizes of CTB-labeled TrkA-positive DRG neurons were similar to those of CTB-labeled CGRP-positive DRG neurons. CONCLUSION: The levator ani muscle is innervated by 3 major subpopulations of primary afferent neurons consisting of cells with large, neurofilament-rich soma and A fibers (putative proprioceptive neurons) and those with small, peptidergic or nonpeptidergic, neurofilament-poor soma and C fibers (putative nociceptive, mechanoreceptive, ergoreceptive, and thermoreceptive neurons). Future investigation is needed to elucidate the relationship between primary sensory neuron subpopulations and changes in neuropeptide and neurotrophin expression on experimental levator ani nerve damage, childbirth, and aging.

Animals↗

Atresia ani with diphallus and separate scrota in a calf: a case report.

Atresia ani, a common genetic defect in animals, is often accompanied by urogenital defects in calves. This paper reports a case of atresia ani with diphallus and separate scrota in a calf. The calf was born with atresia ani; surgery (to open the anus) was performed 3 days after birth. No urogenital abnormalities were noticed until 4 months after birth. At that time, two separate scrota (each containing a testis) and a sac-like structure in the middle of two scrota, were visible. The gait was abnormal, with abduction of the hind limbs while walking. Additionally, the hind legs appeared wider than usual at the hip joints. Two weeks later, two peni (diphallia) was observed, each in a separate preputial sheath. The calf had a normal karyotype on cytogenetic examination. Plasma concentrations of testosterone at 5.5, 6, and 7 months of age were 3.5, 1.9, and 1.7 ng/ml, respectively. At necropsy (7 months of age), the prepuce was thick and the glans of the right penis was adhered to the prepuce. The left penis did not have a urethra or retractor penis muscles. The sac-like structure in the middle of the two scrota contained the urinary bladder and a loop of small intestine. The pubic bone had failed to fuse at the pelvic symphysis. In conclusion, this is the first reported case of atresia ani with diphallus, separate scrota, and pubic bone separation in a calf.

Animals↗

Magnetic resonance imaging of normal levator ani anatomy and function.

OBJECTIVE: To evaluate the anatomy and function of the levator ani in normal women by dynamic magnetic resonance imaging. METHODS: Twelve asymptomatic, nulliparous, premenopausal women with no previous pelvic surgery underwent a dynamic magnetic resonance imaging scan of their pelvis. The origin, orientation, thickness, and function of the two components of the levator ani were studied. RESULTS: The ileococcygeus is a thin muscle with an upward convexity. It slopes forward and medially. It is of variable thickness (mean thickness 2.9 mm, standard deviation 0.8 mm). There are apparent gaps in the muscle diaphragm and at its site of origin from the obturator fascia. The puborectalis is a thicker muscle. It is shaped like a belt encasing the pelvic organs. It is taller posteriorly than anteriorly. It is not attached to the bladder neck, but the midurethra and lower urethra lie in close proximity to it. The puborectalis moves dorsoventrally, whereas the ileococcygeus moves craniocaudally. CONCLUSION: The levator ani is not a single muscle but has two functional components that vary in thickness, origin, and function. The ileococcygeus has a mainly supportive function, whereas the puborectalis has a sphincteric function. Gaps in the diaphragmatic portion of the ileococcygeus are a normal finding. Individual components of the levator ani may be prone to different types of childbirth trauma and should therefore be assessed separately when planning rehabilitation.

Adult↗

Innervation of the female levator ani muscles.

OBJECTIVE: The objective of this study was to characterize the innervation of the human female levator ani muscles. STUDY DESIGN: Detailed dissections of the peripheral innervation of the iliococcygeal, pubococcygeal, puborectal, and coccygeal muscles were performed in 12 fresh-frozen female cadavers (aged, 32-100 years) with the use of transabdominal, gluteal, and perineal approaches. Both the pudendal nerve and the sacral nerve roots that enter the pelvis from the cephalic side were followed from their origin at the sacral foramina to their termination. Pelvic floor innervation was described with reference to fixed bony landmarks, particularly the coccyx, the ischial spine and the inferior pubis. Photographs were taken, and nerve biopsies were performed to confirm the gross findings histologically. Biopsy specimens were stained with Masson's trichrome. RESULTS: In each dissection, a nerve originated from the S3 to S5 foramina (S4 alone, 30%; from S3 and S4, 40%; from S4 and S5, 30%), crossed the superior surface of the coccygeal muscle (3.0 +/- 1.4 cm medial to the ischial spine [range, 1.0-4.2 cm]), traveled on the superior surface of the iliococcygeal muscle innervating it at its approximate midpoint, and continued on to innervate both the pubococcygeal and puborectal muscles at their approximate midpoint. The pudendal nerve originated from the S2 to S4 foramina, exited the pelvis through the greater sciatic foramen, traversed Alcock's canal, and branched to innervate the external anal sphincter, the external urethral sphincter, the perineal musculature, the clitoris, and the skin. Despite specific attempts to locate pudendal branches to the levator ani, none could be demonstrated. Nerve biopsy specimens that were obtained at gross dissection were confirmed histologically. CONCLUSION: Gross dissections suggest that the female levator ani muscle is not innervated by the pudendal nerve but rather by innervation that originates the sacral nerve roots (S3-S5) that travels on the superior surface of the pelvic floor (levator ani nerve). Because definitive studies (eg, nerve transection or neurotracer studies) cannot be performed in humans, further studies that will use appropriate animal models are necessary to confirm and extend our findings.

Adult↗

Levator ani muscle stretch induced by simulated vaginal birth.

OBJECTIVE: To develop a three-dimensional computer model to predict levator ani muscle stretch during vaginal birth. METHODS: Serial magnetic resonance images from a healthy nulliparous 34-year-old woman, published anatomic data, and engineering graphics software were used to construct a structural model of the levator ani muscles along with related passive tissues. The model was used to quantify pelvic floor muscle stretch induced during the second stage of labor as a model fetal head progressively engaged and then stretched the iliococcygeus, pubococcygeus, and puborectalis muscles. RESULTS: The largest tissue strain reached a stretch ratio (tissue length under stretch/original tissue length) of 3.26 in medial pubococcygeus muscle, the shortest, most medial and ventral levator ani muscle. Regions of the ileococcygeus, pubococcygeus, and puborectalis muscles reached maximal stretch ratios of 2.73, 2.50, and 2.28, respectively. Tissue stretch ratios were proportional to fetal head size: For example, increasing fetal head diameter by 9% increased medial pubococcygeus stretch by the same amount. CONCLUSION: The medial pubococcygeus muscles undergo the largest stretch of any levator ani muscles during vaginal birth. They are therefore at the greatest risk for stretch-related injury.

Adult↗

Levator ani muscle anatomy evaluated by origin-insertion pairs.

OBJECTIVE: To examine the published literature and suggest a resolution to the confusion that exists in levator ani muscle descriptions and terminology. DATA SOURCES: A MEDLINE search was performed using the keyword "levator ani," limited to human studies in women. References found in these articles were reviewed to identify research reported before 1966 and articles not included in the search. STUDY SELECTION: Studies were accepted if they contained direct observations of female specimens. Only those that contained specific descriptions or illustrations of the muscle origins and insertions in more than 5 female specimens were included. Review of 265 human studies yielded 9 qualifying articles, and reference tracing disclosed 3 additional reports. TABULATION, INTEGRATION, AND RESULTS: The literature review identified 5 origin-insertion pairs consistently described in studies directly examining the levator ani muscle in women, but 16 terms were used by authors for these 5 components of the muscle. Labeled illustrations often provided more precise information than was provided in the text. Terms were reviewed for inconsistencies of usage and appropriateness of term choice. The terms puboperineal, pubovaginal, and puboanal (for components of the pubovisceral ["pubococcygeal"] muscle), along with puborectal and iliococcygeal, are sufficient to describe the divisions of the levator ani muscle. CONCLUSION: Although there was great diversity and conflict in terms chosen among the original articles, the number of origin and insertion pairs was relatively consistent among authors and confusion can be avoided by standardizing terminology.

Female↗

Appearance of the levator ani muscle subdivisions in magnetic resonance images.

OBJECTIVE: Identify and describe the separate appearance of 5 levator ani muscle subdivisions seen in axial, coronal, and sagittal magnetic resonance imaging (MRI) scan planes. METHODS: Magnetic resonance scans of 80 nulliparous women with normal pelvic support were evaluated. Characteristic features of each Terminologia Anatomica-listed levator ani component were determined for each scan plane. Muscle component visibility was based on pre-established criteria in axial, coronal, and sagittal scan planes: 1) clear and consistently visible separation or 2) different origin or insertion. Visibility of each of the levator ani subdivisions in each scan plane was assessed in 25 nulliparous women. RESULTS: In the axial plane, the puborectal muscle can be seen lateral to the pubovisceral muscle and decussating dorsal to the rectum. The course of the puboperineal muscle near the perineal body is visualized in the axial plane. The coronal view is perpendicular to the fiber direction of the puborectal and pubovisceral muscles and shows them as "clusters" of muscle on either side of the vagina. The sagittal plane consistently demonstrates the puborectal muscle passing dorsal to the rectum to form a sling that can consistently be seen as a "bump." This plane is also parallel to the pubovisceral muscle fiber direction and shows the puboperineal muscle. CONCLUSION: The subdivisions of the levator ani muscle are visible in MRI scans, each with distinct morphology and characteristic features.

Adult↗

Quantification of levator ani cross-sectional area differences between women with and those without prolapse.

OBJECTIVE: Compare levator ani cross-sectional area as a function of prolapse and muscle defect status. METHODS: Thirty women with prolapse and 30 women with normal pelvic support were selected from an ongoing case-control study of prolapse. For each of the two groups, 10 women were selected from three categories of levator defect severity: none, minor, and major identified on supine magnetic resonance scans. Using those scans, three-dimensional (3D) models of the levator ani muscles were made using a modeling program (3D Slicer), and cross-sections of the pubic portion were calculated perpendicular to the muscle fiber direction using another program, I-DEAS. An analysis of variance was performed. RESULTS: The ventral component of the levator muscle of women with major defects had a 36% smaller cross-sectional area, and women with minor defects had a 29% smaller cross-sectional area compared with the women with no defects (P < .001). In the dorsal component, there were significant differences in cross-sectional area according to defect status (P = .03); women with major levator defects had the largest cross-sectional area compared with the other defect groups. For each defect severity category (none, minor, major), there were no significant differences in cross-sectional area between women with and those without prolapse. CONCLUSION: Women with visible levator ani defects on magnetic resonance imaging had significantly smaller cross-sectional areas in the ventral component of the pubic portion of the muscle compared with women with intact muscles. Women with major levator ani defects had larger cross-sectional areas in the dorsal component than women with minor or no defects. LEVEL OF EVIDENCE: II-2.

Case-Control Studies↗

Assessment of shape variation of the levator ani with optimal scan planning and statistical shape modeling.

OBJECTIVE: To capture 3D shape variation of the levator ani during straining with open access MR imaging. METHODS: Optimal scan-planning based on statistical shape modeling is developed for recovering the entire 3D structure of the levator ani from a limited number of 2D imaging planes. Statistical shape modeling ensures optimum material correspondence, and Subspace Reprojection is used to identify the optimum orientation of the imaging plans. The accuracy of the method in using limited 2D imaging planes to instantiate the dynamic structure of the levator ani is assessed with data acquired from 10 asymptomatic subjects. RESULTS: Leave-one-out analysis was performed whereby a model based on a training set consisting of all but one surface was used to instantiate the dynamic surface structure from the corresponding optimal planes. The mean surface distance error for the proposed Subspace Reprojection method is 3.989 +/- 0.790 mm, which is significantly smaller than other approaches. CONCLUSIONS: Surfaces of the levator ani may be instantiated using a limited number of imaging planes as well as a statistical shape model based on a training set of subjects. The proposed technique offers a new way forward for studying dynamic shape changes of 3D structures where complete volumetric imaging is prohibited by the inherent temporal resolution of the scanning technique.

Adult↗