Related Experiment Video
Updated: Aug 12, 2026
14:09
In vitro Functional Characterization of Mouse Colorectal Afferent Endings
Published on: January 21, 2015
Magnetic resonance imaging of normal levator ani anatomy and function
Kavita Singh1, W M N Reid, L A Berger
1Department of Obstetrics and Gynaecology, Royal Free and University College Medical School, London, United Kingdom. kavita@rfhsm.ac.uk
Obstetrics and Gynecology
|February 28, 2002
Summary
The levator ani muscle has two distinct parts: the ileococcygeus (supportive) and puborectalis (sphincteric). Dynamic MRI reveals normal anatomical variations and functional differences crucial for understanding pelvic floor trauma.
Area of Science:
- Pelvic floor anatomy
- Female pelvic medicine
- Medical imaging
Background:
- The levator ani muscle is crucial for pelvic floor support and function.
- Understanding its detailed anatomy and function is essential for diagnosing and treating pelvic floor disorders.
Purpose of the Study:
- To evaluate the anatomy and function of the levator ani muscle in asymptomatic women using dynamic MRI.
- To differentiate the roles of the ileococcygeus and puborectalis components.
Main Methods:
- Dynamic magnetic resonance imaging (MRI) of the pelvis.
- Study included twelve asymptomatic, nulliparous, premenopausal women.
- Analysis of the origin, orientation, thickness, and function of levator ani components.
Main Results:
- The levator ani comprises two components: the thin, supportive ileococcygeus and the thicker, sphincteric puborectalis.
- The ileococcygeus exhibits upward convexity and variable thickness, with normal gaps at its origin.
- The puborectalis functions as a muscular belt, moving dorsoventrally, while the ileococcygeus moves craniocaudally.
Conclusions:
- The levator ani is functionally bipartite, with distinct supportive (ileococcygeus) and sphincteric (puborectalis) roles.
- Apparent gaps in the ileococcygeus are a normal anatomical finding.
- Separate assessment of levator ani components is recommended for planning childbirth trauma rehabilitation.
More Related Videos
Related Concept Videos
01:24Magnetic Resonance Imaging
Magnetic resonance imaging (MRI) is a noninvasive medical imaging technique based on a phenomenon of nuclear physics discovered in the 1930s, in which matter exposed to magnetic fields and radio waves was found to emit radio signals. In 1970, a physician and researcher named Raymond Damadian noticed that malignant (cancerous) tissue gave off different signals than normal body tissue. He applied for a patent for the first MRI scanning device in clinical use by the early 1980s. The early MRI...
01:26Muscles of the Pelvic Floor and Perineum
The muscles of the pelvic floor and perineum are crucial for supporting the pelvic organs, controlling continence, and aiding in sexual function, childbirth, and core stability. They are typically divided into the superficial perineal layer and the deep pelvic floor layer.
Perineal Layer
The perineum is a diamond-shaped area below the pelvic diaphragm, divided into an anterior urogenital triangle that contains the external genitals and a posterior anal triangle housing the anus. The urogenital...
Perineal Layer
The perineum is a diamond-shaped area below the pelvic diaphragm, divided into an anterior urogenital triangle that contains the external genitals and a posterior anal triangle housing the anus. The urogenital...
01:26The Micturition Reflex
Urination, or micturition involves the coordination of the bladder's detrusor muscle and two sphincters to ensure controlled bladder emptying.
The process begins with bladder filling, where the bladder wall stretches as urine accumulates. This stretching activates the urine storage reflex, mediated by the sacral spinal segments and the pontine storage center. Efferent sympathetic impulses stimulate the detrusor muscle to relax and the internal urethral sphincter to contract, facilitating urine...
The process begins with bladder filling, where the bladder wall stretches as urine accumulates. This stretching activates the urine storage reflex, mediated by the sacral spinal segments and the pontine storage center. Efferent sympathetic impulses stimulate the detrusor muscle to relax and the internal urethral sphincter to contract, facilitating urine...
01:25Assessment of the Rectum and Anus
Evaluating the rectum and anus plays a crucial role in conducting a thorough physical examination of the gastrointestinal system. Although it may be uncomfortable and often embarrassing for the patient, it holds immense diagnostic value, particularly in detecting gastrointestinal diseases and abnormalities. This guide will explain how to perform this assessment using inspection and palpation methods.
Rectal Inspection
Begin by inspecting the perianal and anal areas for color, texture, rashes,...
Rectal Inspection
Begin by inspecting the perianal and anal areas for color, texture, rashes,...
01:19Anatomy of the Genitourinary System II: Bladder and Urethra
The lower urinary system consists of the urinary bladder and urethra, which are essential in storing and expelling urine from the body. Together with the internal and external sphincters, these structures work together to regulate urination effectively.Anatomy of the BladderThe urinary bladder is a muscular, stretchable organ behind the pubic bone and in front of the rectum. In females, the bladder is positioned anterior to the vagina and inferior to the uterus, while in males, it is located...
01:27Imaging Studies IV: Magnetic Resonance Imaging
Introduction:Magnetic Resonance Imaging, or MRI, can include a specialized imaging technique of the urinary system known as Magnetic Resonance Urography (MRU). This radiation-free technique uses strong magnetic fields and radio waves to produce detailed images with the help of a computer. MRU is particularly effective for visualizing fluid-filled structures like the kidneys, ureters, and bladder.Applications of MRI in the Genitourinary SystemKidneys and Ureters: MRI detects tumors, cysts,...