Normal Anatomy and Physiology of the Female Pelvis Chapter 41 PDF

NORMAL ANATOMY AND PHYSIOLOGY OF THE FEMALE PELVIS Chapter 41  Introduction to female pelvis ▪ Sonography is often the imaging method of choice for evaluating the female pelvis. ▪ Extensive knowledge of normal anatomy and physiology is essential to properly evaluate the o...

NORMAL ANATOMY AND PHYSIOLOGY OF THE FEMALE PELVIS Chapter 41  Introduction to female pelvis ▪ Sonography is often the imaging method of choice for evaluating the female pelvis. ▪ Extensive knowledge of normal anatomy and physiology is essential to properly evaluate the organs and structures of the female pelvis. ▪ These organs and structures include the uterus, vagina, ovaries, fallopian tubes, urinary bladder, and pelvic colon. ▪ The transabdominal approach requires a full bladder for use as an "acoustic window" and typically uses a 3.5 to 5-MHz transducer. ▪ The endovaginal exam is performed with an empty bladder and uses a higher frequency transducer typically 7.5 - 10 MHz. ▪ The outer boundaries of the pelvis are formed by the pelvic skeleton which is lined with muscles that form the inner margins.  Key Structures of Female Pelvis ▪ Bones ▪ Vagina ▪ Muscles ▪ Cervix ▪ Ligaments ▪ Uterus ▪ Spaces ▪ Fallopian Tubes ▪ Ovaries ▪ Urinary Bladder 3 The Pelvic Skeleton (aka Bony Pelvis)  Functions of Pelvic Skeleton ▪ Weight bearing bridge between spine and legs. ▪ Pathway during childbirth- protects the fetal head. ▪ Protection of pelvic organs  The Bony Pelvis ▪ Consists of four bones: ✔ Two innominate (coxal) bones ✔ Sacrum ✔ Coccyx ▪ Divided into two continuous compartments (true and false pelves) by oblique plane that passes through pelvic brim.  The Pelvic Skeleton—(cont.) Copyright © 2016, Elsevier Inc. All Rights Reserved. 1. Sacrum, 2. Ilium, 3. Ischium, 4. Pubis/Pubic bone, 5. Pubic symphysis, 6. Acetabulum, 7. Obturator foramen, 8. Coccyx  THE PELVIC SKELETON CONT. *** Be able to label 1-8 Copyright © 2018 Wolters Kluwer · All Rights Reserved  The Pelvic Skeleton—(cont.) Front and side view of sacrum and coccyx. 5 fused vertebral bodies and 4 fused bodies of the coccyx. The S-shapes curve creates the posterior wall of the pelvis  Female Pelvis LOCATION 10  Abdominal Regions of Female Pelvis ▪ 3 Specific Regions – Right Iliac – Left Iliac – Hypogastric 11  True vs. False Pelvis Overview ▪ The True Pelvis & False Pelvis are 2 structurally continuous compartments that make up the pelvic cavity. ▪ They are divided by an imaginary line that defines the plane for the True and False pelvic. ▪ This imaginary line is termed the Linea Terminalis (aka iliopectineal line) 12  The Pelvic Cavity and Perineum TRUE PELVIS Is situated inferior to caudal portion of parietal peritoneum. True pelvis is considered the pelvic cavity.  Pelvic Cavity (True Pelvis) ▪ Posterior: Occupied by rectum, colon, ileum. ▪ Anterior: Occupied by bladder, ureters, ovaries, fallopian tubes, uterus, vagina.  True Pelvis- aka Lesser Pelvis Copyright © 2016, Elsevier Inc. All Rights Reserved. ▪ The True pelvis extends from the Linea Terminalis to the pelvic diaphragm inferiorly. ▪ It’s a bowl-shaped cavity aligned posteriorly and inferiorly within the skeletal framework of the pelvis. ▪ It contains scannable organs which consists of the urinary bladder, uterus and ovaries. It also houses the adnexa and much of the small 15  False Pelvis – aka Greater Pelvis Defined as the more superior aspect of pelvic cavity, extending from iliac crests superiorly to Linea terminalis inferiorly Contains mainly bowel. Copyright © 2016, Elsevier Inc. All Rights Reserved. 16 PELVIC MUSCLES  The Abdominal Wall ▪ Muscles extend superiorly from xyphoid process to symphysis pubis inferiorly ✔ Paired rectus abdominis muscles longitudinally along either side of linea alba – “6 pack” ✔ External obliques ✔ Internal obliques ✔ Transversus abdominis muscles anterolaterally  Transverse abdominis muscles Transverse abdominis Copyright © 2016, Elsevier Inc. All Rights Reserved. 19  Muscles of the Pelvis ▪ Psoas major: Pelvic sidewall ▪ Iliacus: Pelvic sidewall ▪ Piriformis: Posterolateral wall ▪ Obturator internus: Anterolateral pelvic sidewall ▪ Levator ani: Pelvic floor (diaphragm) ▪ Coccygeus: Posterior pelvic floor (diaphragm)  Muscles of the True Pelvis ▪ Piriformis muscles ▪ Obturator internus muscles ▪ Muscles of pelvic diaphragm ✔ Levator ani: ▪ Pubococcygeus muscles, iliococcygeus muscles, puborectalis muscles ✔ Coccygeus muscles  Muscles of the True Pelvis Obturator internus Piriformis OI anterior and lateral Piriformis – anterior and lateral; more superior and cross grain with OI 22  Obturator Internus Muscles ▪ Originates along arcuate line of innominate bones ▪ Obturator internus Courses parallel to lateral walls of true pelvis ▪ Triangular muscle that narrows inferiorly as it passes thru the lesser sciatic notch/foramen to attach to the greater trochanter of femur. 23  Piriformis Muscles ▪ Originate in the most posterior portion of the true pelvis, along the lower portion of the sacrum, posterior to Obturator the uterus. internus Piriformis ▪ Flat triangular muscles that travel anterolaterally, and cross-grain to the OI muscles. ▪ They attach to the superior aspect of each greater trochanter. 24 Muscles of the True Pelvis  Muscles of the Pelvic Diaphragm or Pelvic Floor ▪ Most caudal structures in pelvic cavity. ▪ Comprised of 3 Paired Coccygeus Muscles 1. Pubococcygeus 2. Iliococcygeus 3. Coccygeus 26  Pubococcygeus muscles Observe the diagram – This is a transverse view Note the location of the pubis and the coccyx Pubococcygeu s Note the three groups of Muscles muscles – anterior, middle, and posterior Which on encircles the urethra, vagina, and anus? Pubococcygeus is the most medial and anterior muscle pair of the pelvic diaphragm muscles. 27  Iliococcygeus muscles Pubococcygeus Located lateral to Muscles pubococcygeus muscles Extend from obturator fascia and ischial spine anteriorly to coccyx Iliococcygeu posteriorly s Muscles 28  Levator Ani 1. Pubococcygeu s 2. Iliococcygeus 3. Puborectalis 29  Coccygeus muscles Observe the diagram Pubococcygeus What is the most posterior Muscles midline structure? Coccygeus is the most posterior muscle pair of the pelvic diaphragm Iliococcyge us These muscles extend from Muscles ischial spine to sacrum and Coccyge us coccyx Muscles 30 Pelvic Diaphragm/Pelvic Floor ▪ The pelvic floor or pelvic diaphragm consists of the Levator ani and coccygeus muscles. KNOW THIS!!! The Pelvic Muscles- pelvic floor  One Minute Paper ▪ List the anterior midline bone of the pelvis. ▪ List the posterior midline bone of the pelvis. ▪ List the 4 muscles of the True Pelvis ▪ Name the most posterior muscle of the pelvic floor. Try this at home without your notes! 33  Muscles of the False Pelvis ▪ Psoas major ▪ Iliacus muscles ▪ In false pelvis, psoas muscles join with iliacus muscles to form iliopsoas muscles.  Muscles of the False Pelvis Psoas major muscles Arises from the lumbar spine and descends into the false pelvis. Courses laterally and anteriorly into the false pelvis along the pelvic sidewalls and terminate in the groin. 35  Muscles of the False Pelvis Iliopsoas muscles Psoas muscle joins iliacus muscles at level of iliac crests to form iliopsoas bundles of the false pelvis Each iliopsoas muscle courses anteriorly along linea terminalis, to travel over the pelvic brim and insert into lesser Copyri ght © trochanter of the femur 2016, Elsevi er Inc. All Rights Reser 36 ved. Muscles of the False Pelvis Muscles of the false pelvis THE PELVIC MUSCLES—(CONT.) Iliopsoas Sag Copyright © 2018 Wolters Kluwer · All Rights Reserved THE PELVIC MUSCLES—(CONT.) Iliopsoas Transverse Copyright © 2018 Wolters Kluwer · All Rights Reserved THE PELVIC MUSCLES—(CONT.) Get familiar with surrounding structures! Copyright © 2018 Wolters Kluwer · All Rights Reserved  Select the False Pelvis Muscle ▪ Iliopsoas ▪ Levator Ani ▪ Obturator Internus ▪ Piriformis 42 PELVIC LIGAMENTS  Pelvic Ligaments The uterus is supported in its midline position by multiple paired ligaments. ▪ Broad ligaments ▪ Round ligaments ▪ Uterosacral ligaments ▪ Cardinal ligaments 44  Pelvic Ligaments Cont. The ovary is supported by 2 ligaments. ▪ Infundibulopelvic ligament ▪ Ovarian ligament Don’t Ovary Act!! 45  Think ! Medical Terminology Review ▪ Salpinx or Salpingo ▪ Utero ▪ Sacral ▪ Oophoro ▪ Broad and Bat start with B ▪ Cardinal and cervix start with C ▪ Infundibulum is part of fallopian tube near the ovary 46  Broad Ligaments (Uterus) ▪ Double folds of peritoneum that extend from uterine cornua (superior aspect) to the lateral pelvic walls and drapes over the fallopian tubes, uterus and ovaries. ▪ Sort of like plastic wrap – if you hold up the sides, it holds up uterus from side to side ▪ It’s a Broad, flat ligament that resembles bat wings – (B, Broad, Bat, Flat) ▪ Provides minimal support for uterus ▪ The fallopian tube, round ligament, ovarian ligament, and vascular structures of the uterus and ovaries lie between two layers of each broad ligament 47  Broad Ligaments Copyri ght © 2016, Elsevi er Inc. All Rights Reser 48 ved.  Round Ligaments (Uterus) ▪ Fibrous cords that occur in front of and below the fallopian tubes, between the layers of the broad ligament. ▪ Holds the uterus from front to back; assists in holding the uterine fundus and body in a forward bend position. ▪ They extend from both sides of the superior aspect of the uterus and course upward and lateral toward the pelvic wall. ▪ They pass over the pelvic brim, through the inguinal canal, and are secured at the labia majora. 49  Round Ligaments (Uterus) https://radiologykey.com/cervical-cancer 50  Pelvic Ligaments Cervix Cardinal ligaments (C) ▪ Extend from upper cervix and uterine isthmus to the lateral walls of pelvis. Uterosacral ligaments ▪ Extend from posterior aspect of cervix around lateral walls of rectum to sacrum 51  Pelvic Ligaments Cervix https://radiologykey.com/cervical-cancer 52  Pelvic Ligaments (Ovary) Infundibulopelvic ligament (aka Suspensory ligament) ▪ Extends from infundibulum and lateral aspect of the ovary to lateral pelvic wall Ovarian ligament ▪ Supports medial aspect of ovary to uterine cornua. ▪ Lies within the peritoneal folds of the Broad Ligament. TOGETHER THEY SUPPORT THE OVARIES, MAINTAINING THEIR RELATIVE POSITIONS IN THE ADNEXAL REGION. 53  Pelvic ligaments (Ovarian) Cont. https://www.memorangapp.com/flashcards/156255/Anatomy+-+pelvic+ligam ents/ 54  Which ligament supports the cervix? ▪ Cardinal ▪ Round ▪ Broad ▪ Suspensory 55 PELVIC ORGAN ANATOMY The Organs Of The Pelvis 1. Urinary bladder and urethra 2. External genitalia 3. Uterus, 2 fallopian tubes, and vagina 4. 2 Ovaries 5. Colon and rectum  EXTERNAL GENITALIA ▪ Mons pubis ▪ Labia majora ▪ Labia minora ▪ Clitoris ▪ Urethral opening ▪ Vestibule of vagina **It is important to recognize external genitalia for translabial, or trans perineal scanning techniques! The Pelvic Organs—(cont.) ANATOMY OF BLADDER  Bladder Anatomy ▪ Located in the anterior segment of the pelvic cavity, anterior to the uterus and vagina, and posterior to the pubic symphysis. ▪ Anchored in place by the pubovesical ligament. ▪ The function of the bladder is to collect and store urine until it empties through the urethra. https://www.mountnittany.org/articles/healthsheets/36872 61  Bladder Anatomy Cont. ▪ The 3 main sections of the bladder include the Apex, Base, and Neck. ▪ The Apex is located posterior to the pubic bone. ▪ The Base is anterior to the vagina, superior surface related to the uterus. ▪ The Neck rests on the Copyri ght © upper surface of 2016, Elsevi urogenital diaphragm. er Inc. All Rights Reser 62 ved.  Bladder Cont. ▪ Ureters are the two tubes that carry urine from the kidneys to the bladder. ▪ As the ureters descend inferiorly from the kidneys they run anteriorly and medially, passing anterior to the psoas major muscles along the lateral aspect of the cervix and upper portion of the vagina. ▪ The ureters enter the Copyri bladder posteriorly at the ght © 2016, trigone, where the urethra Elsevi https://www.hopkinsmedicine.org/health/wellness-and-prevention/anatomy-of-the-urinary-system er exits. Inc. All Rights Reser 63 ved.  Bladder Cont. ▪ When the bladder is empty or slightly filled, it remains entirely within the true pelvis ▪ As it fills the superior surface becomes distended and rises behind the lower anterior abdominal wall pushing moveable pelvic organs, small bowel, and peritoneum away from its walls and into the false https://www.mountnittany.org/articles/healthsheets/36872 pelvis. 64  Bladder Size ▪ The normal urinary bladder has a smooth thin wall. ▪ When distended (top of bladder exceeds fundus of uterus), bladder wall thickness should measure < 3mm, with a mean of 1.5mm. ▪ When empty or partially full, wall will appear thicker but should not measure >5mm. ▪ Urine jets are routinely imaged and visible on sonogram with the use of color doppler. 65 Bladder on Sonogram Bladder Wall Bladder walls thick or thin?  Bladder Cont. Use full bladder as a window to the uterus!  Pelvic Colon Anatomy ▪ The sigmoid colon is located the true pelvis. ▪ It is variable in length and position and is continuous with the descending colon in the left lower quadrant. ▪ The sigmoid colon descends towards the rectum inferiorly and posteriorly at the level of the 3rd sacral vertebra. https://ultrasoundregistryreview.com/OBGYNtrial.html ▪ This location can create difficulties during ultrasound exams. 69  Rectum Anatomy ▪ The rectum is located posterior to the vagina at the level of the 3rd sacral vertebra. ▪ It connects the sigmoid colon the anal canal. ▪ It is retroperitoneal and is fixed in its position. ▪ Fecal matter in the rectum causes irregular shadowing and produces very dense bright echoes on ultrasound. https://www.google.com/url?sa=i&url=https%3A%2F%2Ffascrs.org%2Fpatients%2Fdiseases-an d-conditions%2Fa-z%2Frectal-prolapse-expanded-version&psig=AOvVaw0vXWQA5-iE9CfpVQDRO iwb&ust=1599664039503000&source=images&cd=vfe&ved=0CAIQjRxqFwoTCMDWyojr2esCFQA AAAAdAAAAABAI 70 Rectum/bowel cont.  Bowel on ultrasound Transabdomin Transvagin al al ANATOMY OF VAGINA  Vaginal Anatomy ▪ The vagina is a collapsed muscular tube that extends from the external genitalia to the cervix of the uterus. ▪ It lies in the true pelvis, posterior to the urinary bladder, and anterior to the rectum. ▪ It measures approx 7-10 cm in length and is longest along its anterior wall. 74  Vaginal Anatomy Cont. ▪ Vaginal walls are composed of a mucosal lining of epithelial cells, a thin smooth muscle wall, and an outer adventitia. This makes the vagina highly elastic. ▪ It is easily distended during sexual intercourse and childbirth and is the passageway for products of menstruation. ▪ In a relaxed state the vaginal walls collapse together and the epithelial lining folds into transverse ridges, or rugae. 75  Vaginal Anatomy Cont. ▪ The uterine cervix protrudes into the upper portion of the vaginal canal forming four archlike recesses called fornices. ▪ The posterior vaginal wall attaches higher on the cervix and the fornices are blind pockets formed by the inner surface of the vaginal walls and outer surface of the cervix. 76  VAGINAL FORNICES 1 ANTERIOR FORNIX 1 POSTERIOR FORNIX 2 LATERAL FORNICES https://slideplayer.com/slide/10413015/ 77 Vagina ANATOMY OF UTERUS  Uterus ▪ Lies in true pelvis between bladder and rectum. ▪ It is pear shaped and the largest organ in the normal female pelvis when the bladder is empty. ▪ It is aligned midline in the body and held loosely in place by the broad and round ligaments. 80  Uterus Cont. ▪ Uterine walls are composed of three tissue layers: – Endometrium – Myometrium – Perimetrium (Serosa) 81  Layers of the Uterus ▪ Perimetrium: Serous outer layer of uterus; serosa. ▪ Myometrium: Muscular middle layer of uterus composed of thick, smooth muscle supported by connective tissue. ▪ Endometrium: Inner mucous membrane, glandular portion of uterine body.  3 Layer of Uterus https://slideplayer.com/slide/10413015/ 83  Endometrium ▪ The endometrium is the innermost layer of the uterus. It is a highly vascular, mucosal layer that forms the walls of the endometrial canal. ▪ The endometrium consists primarily of 2 layers: the functional layer (zona functionalis) and the basal layer (zona basalis). ▪ The functional layer is a superficial layer of glands and stroma (supporting tissue) that shed with menses. Sonographic appearance will vary with menstrual cycle and hormonal status. ▪ The basal layer is a deeper thin layer of blind ends of endometrial glands that do not shed with menses but help regenerate new endometrium after menses. 84  Endometrium Cont. ▪ The endometrium changes dramatically in response to the cyclic hormonal flux of ovulation. ▪ It varies in sonographic appearance and structure, depending on the patient’s menstrual status and period of life. ▪ The normal premenopausal range of the endometrial thickness is 4mm – 14mm. 85  Endometrium Cont. (Postmenopausal) ▪ Postmenopausal endometrial thickness should not exceed 5mm without the use of Hormone Replacement Therapy (HRT). ▪ For women taking HRT the endometrial thickness can be altered. The use of estrogen may thicken the endometrium up to 8mm and be considered normal. 86 Endometrium on sonogram How can the endometrial tell time?  Myometrium ▪ The myometrium is the middle muscular layer and forms the bulk of the uterus. ▪ Consists of three layers of thick, smooth muscle. ▪ This combination of muscles layers is responsible for the dramatic enlargement of the uterus during pregnancy, and for producing muscle contractions necessary to expel the fetus at parturition. ▪ The Outer layer is adjacent to the serosa and is separated from the intermediate layer by arcuate vessels. ▪ The Intermediate layer is the thickest of the three layers. ▪ The Inner layer (junctional zone) is a thin layer adjacent to the endometrium. 88  Serosa ( Perimetrium) ▪ The serosa (perimetrium) is the thin membrane that covers the myometrium and forms the outer layer of the uterus. ▪ It is part of the parietal peritoneum. ▪ Uterus is covered with peritoneum to the level of the isthmus. (forming the potential spaces) 89  Uterus Anatomy ▪ Uterus is divided into four sections: – Fundus – Body (Corpus) – Isthmus – Cervix 90  Uterus Anatomy Cont. The fundus is the widest and most superior segment of the uterus and is situated between the insertion of the uterine tubes at the level of the uterine cornua. It is continuous with the body and largest part of the uterus, called the corpus. 91  Uterus Anatomy Cont. ▪ The uterine corpus or body lies between the fundus and the cervix. ▪ It is the largest portion of the uterus and houses the uterine cavity. ▪ It is connected to the cervix by a constriction or narrowing called the isthmus. This is the point where the uterus bends either anteriorly or posteriorly when the bladder is empty. 92  Uterine Anatomy Cont. ▪ The cervix is the lower cylindrical portion of the uterus that projects into the vagina. ▪ The normal cervix measures 2-3cm in length. ▪ The surface of the cervix is divided into the exocervix and the endocervix. 93  Uterus Anatomy Cont. ▪ The exocervix is a squamous epithelium continuous with the vagina. ▪ The surface of the endocervix is made up of columnar cells, which excrete mucus. Copyright © 2016, Elsevier Inc. All Rights Reserved. 94  Uterus Anatomy Cont. ▪ The cervix is constricted at its upper end by the internal os and at its lower end by the external os. ▪ The internal cervical os is the junction of the endocervical canal and the endometrial canal at the uterine isthmus. (area of slight narrowing) ▪ The external cervical os is the junction of the cervical https://histologyblog.com/2013/01/20/histoquarterly-cervix/ canal with the vaginal canal. 95  Uterus Anatomy Cont. ▪ The endometrial, endocervical, and endovaginal canals form a continuous channel through which the fetus passes at birth. ▪ The cervix becomes thinner and the os become wider in preparation for exit of Copyright © 2016, Elsevier Inc. All Rights Reserved. the fetus. 96  Recall Which layer of the endometrium sheds with menses?  Premenarchal Length 1cm – 3cm, A/P 0.5cm - 1.0cm Trans 0.5cm – 1cm The cervix is larger than the uterine body; uterus lacks the pear Shape Nulliparous menarchal (menstrual age 8-15) Length 6.0cm – 8.0cm, A/P 3.0cm – 5.0cm Trans 3.0cm – 5cm Uterus takes on the pear shape appearance. SIZE OF UTERUS Multiparous menarchal Dimensions can increase up to 2.0cm Postmenopausal (uterus shrinks) Length 3.5cm – 5.5cm, A/P 2.0cm - 3.0cm Height and width 2cm – 3cm Postpartum Uterus remains enlarged 4-8 weeks following delivery 98 Copyright ©Copyright © 2018 2016, Elsevier Inc.Wolters Kluwer All Rights · All Rights Reserved Reserved.  UTERINE SIZE AND SHAPE Shape and size will vary markedly with age and parity. At birth, the uterus is more adult shaped due to influx of maternal hormones. After birth, the uterus will will shrink due to lack of estrogen until the beginnings of puberty. By puberty, the uterus will grow to the shape of an inverted pear. The size will increase with each pregnancy but will shrink and regress post-menopause. Copyright © 2018 Wolters Kluwer · All Rights Reserved UTERINE SIZE AND SHAPE Copyright © 2018 Wolters Kluwer · All Rights Reserved  MEASURING THE UTERUS **Take note where Uterus ends, and Vagina begins! Copyright © 2018 Wolters Kluwer · All Rights Reserved SEGMENTS OF THE UTERUS ON SONOGRAM Copyright © 2018 Wolters Kluwer · All Rights Reserved  Uterine Positions ▪ Uterine position is variable and changes with the distention of the bladder, and tight vs loose ligaments. ▪ Cervix fixed in midline, but uterine body mobile and may lie obliquely on either side of midline ▪ Flexion refers to axis of uterine body relative to cervix; version refers to axis of cervix relative to vagina. (flexes at the isthmus)  Uterine Positions (cont.) ▪ The most common position for the uterus is anteverted or anteflexed with a non-distended bladder. ▪ Uterine position is anteverted when the cervical canal forms a 90-degree angle or less with the vaginal canal. ▪ Uterine and cervical canal in same axis. ▪ Anteflexed is when then body and fundus of the uterus are curved forward on the cervix towards the bladder. ▪ In nulliparous females, the round ligaments help to hold the uterus in an anteverted, anteflexed position  Uterine Positions (cont.) ▪ Anteversion: Most common position; fundus and body bent forward toward cervix. ▪ Dextroversion (Right) or levoversion (Left): Normal variant in absence of pelvic masses. ▪ Retroversion: Entire uterus tilted posteriorly. ▪ Retroflexion: Fundus and body bent backward towards cervix. Uterine Positions  Anteverted Uterus 24-year-old woman with anteverted uterus. Ultrasound image shows cervix and body of uterus are at almost at same axis. Most common uterine position. Endometrium and cervical canal are defined in white; calipers show https://www.ajronline.org/doi/pdf/10.2214/AJR.12.10403 endometrial thickness. 107  Anteverted Anteflexed Uterus 32-year-old woman with anteverted anteflexed uterus. Ultrasound image shows uterus at right angle to vaginal probe and extending left so transducer lies alongside its anterior aspect. Endometrium and cervical canal are defined in white. https://www.ajronline.org/doi/pdf/10.2214/AJR.12.10403 108  Retroverted Uterus 28-year-old woman with retroverted uterus. Ultrasound image shows transducer encountering posterior aspect of uterus and body extending to right. Cervix and body of uterus are almost in same axis. Endometrium and cervical canal are defined in white. https://www.ajronline.org/doi/pdf/10.2214/AJR.12.10403 109 Copyright © 2016, Elsevier Inc. All Rights Reserved.  Retroverted Retroflexed Uterus 19-year-old woman with retroverted retroflexed uterus. Cervix and body of uterus, are both angled to right. Endometrium and cervical canal are defined in white. https://www.ajronline.org/doi/pdf/10.2214/AJR.12.10403 110  FALLOPIAN TUBE ANATOMY 111 Copyright © 2016, Elsevier Inc. All Rights Reserved.  Fallopian Tube Anatomy Coiled, muscular, bilateral tubes emerging from the cornua of uterus, and open into the peritoneal cavity at the lateral end. They are approximately 10-12 cm in length and 1-4 mm in diameter. They are contained in the upper margin of the broad ligament and curve over the ovary. Copyright © 2016, Elsevier Inc. All Rights Reserved. 112  Fallopian Tube Anatomy 3 layers Outer layer of peritoneum (serosa) Middle muscular layer that helps move the fertilized ovum to the uterine cavity thru peristalsis. Internal mucosal layer that is continuous with the lining of the uterus. (endometrium) 113  Fallopian Tube Anatomy Divided into four segments: Interstitial Isthmus Ampulla Infundibulum 114  Fallopian Tube Anatomy Cont. The interstitial, or intramural, segment of the uterine tube is the narrowest portion and is enclosed within the muscular wall of the uterus at the cornua. At approximately 1cm in length, it is highly vascular and a very dangerous location for an ectopic pregnancy. 115  Fallopian Tube Anatomy Cont. The isthmus is immediately adjacent to the uterine wall, connected to the interstitial segment. It is a short, straight, narrow portion of the tube. Measures approximately 2 cm in length. The tube widens laterally, leading to the ampullary and infundibular sections. 116  Fallopian Tube Anatomy Cont. The longest and most coiled portion of the uterine tube is the ampulla. Measures approx 5.0 cm in length. Fertilization most often occurs in the ampulla. The mucosal lining of the ampulla folds into complex matrices, filling much of the tubular lumen. 117  Fallopian Tube Anatomy Cont. The infundibulum is the funnel-shaped end and widest portion of the uterine tube. The tube terminates at the fimbriated end of the infundibulum and opens into the peritoneal cavity adjacent to the ovary. The fimbriae are hair like structures that grab the ovum and direct it into the tube after ovulation. 118 Fallopian Tubes—(cont.)  RECALL WHAT IS THE LARGEST PORTION OF THE UTERUS?  RECALL WHAT IS THE NARROWEST MOST VASCULAR PORTION OF THE FALLOPIAN TUBE?  ANATOMY OF OVARIES 122 Copyright © 2016, Elsevier Inc. All Rights Reserved.  Ovary Anatomy The ovaries are almond shaped structures located in the adnexa of the true pelvis, that usually lie posterior to the uterus at the level of the cornua. They are suspended from the posterior aspect of the broad ligament in a fold of peritoneum call the mesovarium. They are supported medially by the ovarian ligaments and laterally by the suspensory (infundibulopelvic) ligament. The position of the ovaries is https://www.researchgate.net/figure/Illustration-of-ovarian-ligaments-Refe rences-Department-of-Radiology-Instituto_fig2_264762527 variable due to the laxity of the ligamentous attachments. Anterior to the iliac artery and vein. 123  Ovarian Anatomy ▪ Consist of outer layer, or cortex, which surrounds central medulla. ▪ Cortex consists primarily of follicles in varying stages of development and is covered by layer of dense connective tissue, tunica albuginea.  Ovaries ▪ Tunica albuginea surrounded by single, thin layer of cells known as germinal epithelium. ▪ Central medulla composed of connective tissue containing blood, nerves, lymphatic vessels, and some smooth muscle at region of hilum. Ovarian Anatomy  Ovary Anatomy Cont. ▪ The ovaries have a smooth outer surface during early years. ▪ With age the ovary will become puckered and pitted within a year of no ovulatory activity. ▪ Menopause will cause the ovaries to become atrophic. ▪ The ovaries produce the reproductive cell, the ovum, and two hormones: estrogen and progesterone which is secreted by the corpus luteum. ▪ These steroidal hormones are responsible for producing and maintaining gender characteristics, preparing the uterus for implantation of a fertilized egg, 127 and developing mammary glands in the female.  Ovary Anatomy Cont. ▪ When we measure the ovary, we measure length, width and depth. ▪ Ovarian size is often stated in terms of volume. ▪ Volume =(length x width x depth) x 0.523 ▪ Normal ovaries will be largest during menarchal years and will shrink postmenopausal. 128  ▪Menarchal years ▪ Length 2.5 cm – 5.0 cm ▪ Width 1.5 cm – 3.0 cm ▪ A/P 0.6cm – 2.2 cm. ▪ Ovarian volume: 10cm3 with upper limits of 18 cm3 – 22 cm3 AVERAGE ▪ Clinical Measurement OVARIAN 3cm x 2cm x 2cm SIZES ▪Premenarchal ovarian volume : 3 cm3 ▪Postmenopausal ovarian volume: 5.8 cm3 **Postmenopausal volume >= 8 cm3 is considered abnormal 129 PELVIC VASCULATURE Pelvic Vasculature **See pages 1169-1170 ; Box 41.16 Pelvic Vasculature PHYSIOLOGY OF FEMALE PELVIS  Gynecologic Physiology Objectives ▪ Endocrine Cycle (big picture) ▪ Menstrual Cycle ▪ Ovarian Cycle ▪ Uterine or Endometrial Cycle ▪ Sonographic interpretation 134  REVIEW OF PELVIC ANATOMY Copyright © 2016, Elsevier Inc. All Rights Reserved. 135  Physiology – Endocrine Cycle Buzz Words Hypothalamus GnRh Anterior Pituitary FSH LH Ovary Estrogen Progesterone 136  Between puberty and menopause, the female reproductive system normally undergoes a monthly menstrual cycle Physiology (Big Picture)- Menstrual cycle usually follows a 28-day course, during which a single oocyte (immature egg cell) reaches maturity and Endocrine is released into the genital tract Cycle Hormones secreted by the anterior pituitary gland and by the ovary itself control changes in ovary and uterine endometrium throughout this cycle 137  Menstrual Cycle ▪ A female’ reproductive years begin around the age of 11-13 with the onset of menses and end around the age of 50 when menses ceases. ▪ The average menstrual cycle is 28 days and begins with the first day of menstrual bleeding. 138  Menstrual Cycle Medical Terminology ▪ Poly – ▪ Oligo - 139  MENSTRUAL CYCLE Polymenorrheic - Oligomenorrheic – menstrual cycle menstrual cycle occurs at intervals occurs at intervals less than 21 days >35 day apart. apart. 140  MENSTRUAL CYCLE Menstrual Status Menarche – Menopause – Premenarche – reaching puberty, cessation of menses prepuberty before normal monthly for more than 1 onset of menses occurrence of year. menses. 141  Abnormal Menses ▪ Polymenorrhea: Menstrual cycles with interval 35 days ▪ Menorrhagia: Abnormally heavy or long periods ▪ Dysmenorrhea: Painful periods ▪ Amenorrhea: Absence of menstruation  Menstrual Cycle ▪ Day 1 of menstrual cycle is the first day of menstrual bleeding. ▪ Days 1-13 are preovulatory. - Follicular Phase of the ovarian cycle - Proliferative Phase of the uterine cycle. ▪ Day 14 (on or around) ovulation occurs. ▪ Days 15-28 post ovulatory. - body is preparing for pregnancy - Luteal Phase of the ovarian cycle - Secretory Phase of the uterine cycle 143  MENSTRUAL CYCLE ▪ THE MENSTRUAL CYCLE IS CONTROLLED BY THREE ENDOCRINE GLANDS THAT PRODUCE HORMONES OR “CHEMICAL MESSENGERS”. 1. HYPOTHALAMUS 2. ANTERIOR PITUITARY GLAND 3. OVARIES Copyright © 2016, Elsevier Inc. All Rights Reserved. 144  Menstrual Cycle – Endocrine Glands Hypothalamus ▪ Located in the brain. ▪ Produces 2 gonadotrophin-releasing hormones(GnRH) - FSHRF – Follicle stimulating hormone releasing factor. - LHRF – Luteinizing hormone releasing factor. 145  Menstrual Cycle Anterior Pituitary Gland ▪ Located in the brain ▪ Produces and secretes gonadotrophins, which stimulate changes in the ovaries. - Follicle Stimulating Hormone (FSH) – stimulates follicular growth within the cortex of the ovary. Responsible for egg maturation and increased estrogen production, - Luteinizing hormone (LH) – stimulates ovulation and the formation of the corpus luteum which produces estrogen and large amounts of progesterone to support implantation of a fertilized egg. 146  Menstrual Cycle ▪ The control of GnRH is through a negative feedback system. ▪ High levels of estrogen in the blood causes a negative feedback to the hypothalamus and pituitary to reduce the production of FSH and LH. ▪ Low levels of estrogen in the blood causes a causes the hypothalamus and pituitary to increase the production of FSH and LH. (w/one exception the LH surge) 147  Menstrual Cycle Ovaries produce: ▪ Estrogen ▪ Progesterone 148  Menstrual Cycle Estrogen ▪ Produced by the maturing ovarian follicles. ▪ Influences the secretion of gonadotrophins from the pituitary gland using negative feedback mechanism. - High levels of estrogen inhibits the release FSH and LH. - Low levels of estrogen stimulates the release of FSH and LH. ▪ Stimulates endometrial growth. ▪ Induces fallopian tube contractions to assist in the movement of the fertilized egg to the uterine cavity. ▪ Stimulates the production and secretion of cervical mucous. ▪ Responsible for female secondary sex characteristics. 149  Menstrual Cycle Progesterone ▪ Produced by the corpus luteum of the ovary. (formed in 2nd half of menstrual cycle) ▪ Levels increase rapidly after ovulation. - Peaks around 7th day after ovulation - High levels of progesterone inhibits LH production within the pituitary gland blocking the LH surge that causes ovulation. ▪ Induces the glands within the endometrium to become secretory in nature and prepare the endometrium for pregnancy. ▪ Inhibits the secretory activity of the cervix. ▪ Increases basal body temp ▪ Stimulates mammary glands in the breast. 150  Menstrual Cycle ▪ Low levels of estrogen and progesterone will cause menstruation. (continues until pregnancy occurs) - spiral arteries within the endometrium atrophy - endometrial lining disintegrates and sloughs off - low levels of estrogen stimulate FSH and LH – menstrual cycle begins again: 1. FSH stimulates ovarian follicle growth 2. Endometrium undergoes repair and growth under the influence of estrogen 3. Increasing estrogen levels stimulates increased LH production… 151  Menstrual Cycle 152  Menstrual Cycle 153  ▪ DURING THE MENARCHAL YEARS, AN OVUM(MATURED OOCYTE) IS RELEASED ONCE A MONTH BY ONE OF THE TWO OVARIES. ▪ THIS PROCESS IS OVULATION. ▪ IT IS SPECULATED THAT THE RELEASE OF THE OVUM ALTERNATES BETWEEN THE LEFT AND RIGHT OVARY MONTH TO MONTH. OVARIAN ▪ ALL OVA BEGIN DEVELOPMENT DURING EMBRYONIC LIFE CYCLE AND REMAIN IN SUSPENDED ANIMATION WITHIN PRIMORDIAL FOLLICLES AS IMMATURE OOCYTES UNTIL PUBERTY AND THE ONSET OF MENSES. ▪ EACH OVARY CONTAINS APPROXIMATELY 200,000 OOCYTES AT THE TIME OF BIRTH. ▪ SOME OF THESE OOCYTES WILL MATURE AND BE RELEASED DURING OVULATION AND OTHERS WILL DEGENERATE THROUGHOUT LIFE. 154  Ovarian Cycle 3 Phases ▪ Follicular Phase (Days 1 -13) ▪ Ovulation (Day 14) ▪ Luteal Phase (15-28) 155  Ovarian Cycle Follicular Phase ▪ Around Day 1 of the menstrual cycle, FSH stimulates the growth of 4-8 primordial follicles into primary ovarian follicles. ▪ Day 4-5 only one primary follicle fills with fluid and becomes a secondary follicle. - the primary oocyte is off to one side of the follicle and is surrounded by follicular cells called the cumulus oophorus. 156  Ovarian Cycle Follicular Phase Cont…. ▪ Days 6-13 – Estrogen and a small amount of progesterone are produced by the growing follicles. ▪ Only 1 follicle, known as the graafian follicle or dominant follicle will continue to grow and mature. ▪ The graafian follicle reaches 2.0 – 2.5cm and bulges on the surface of the ovary. ▪ Other follicles will degenerate. Copyri ght © 2016, Elsevi er Inc. All Rights Reser 157 ved.  Ovarian Cycle Visualization of cumulus oophorus indicates ovulation is coming. Cumulus oophorus 158  Ovarian Cycle dominant follicle 159  Ovarian Cycle Follicular Phase Cont… (Days 6-13) ▪ Increased estrogen production from the graafian follicle stimulates the production of LH (Luteinizing Hormone) in the pituitary gland. ▪ LH levels will begin to rapidly increase in the blood over the next 24-36 hours. ▪ This is known as the LH surge. ▪ LH peak is reached 10-12 hours prior to ovulation. 160  Follicular Phase Copyri ght © 2016, Elsevi er Inc. All Rights Reser 161 ved.  Ovarian Cycle Ovulation Phase ▪ Day 14 – The surge of LH triggers ovulation. ▪ Ovulation is an explosive release of the ovum from the ruptured graafian follicle. ▪ The rupture of the graafian follicle is associated with small amounts of fluid in the posterior-cul-de-sac. ▪ The ovum is swept into the infundibulum of the fallopian tube. 162  Ovarian Cycle ▪ Some women can tell when they are ovulating because of a midcycle pain; typically, a dull ache on either side of the lower abdomen lasting a few hours. ▪ The term “middleschmerz”, from the German word meaning middle pain, is used to describe this sensation. Copyri ght © 2016, Elsevi er Inc. All Rights Reser 163 ved.  Ovarian Cycle https://www.beingtheparent.com/stages-and-phases-of-ovulation/ 164  Ovarian Cycle Luteal Phase – (post ovulation) ▪ Days 15-28 – Cells in the lining of the ruptured follicle undergo luteinization, stimulated by LH. ▪ The ruptured follicle become the corpus luteum, meaning “yellow body”. ▪ Corpus luteum immediately begins secreting progesterone and estrogen. ▪ 9-11 days after ovulation, the corpus luteum degenerates, causing progesterone levels to drop. Copyri ght © ▪ 2016, Elsevi As progesterone levels decline, menstruation occurs, and er Inc. the cycle begins again. All Rights Reser 165 ved.  Ovarian Cycle ▪ If fertilization occurs, the pregnancy will immediately begin to secrete hCG (human chorionic gonadotropin) to sustain the corpus luteum which will secrete progesterone for 3 more months until the placenta takes over. ▪ The Luteal Phase does not usually vary in length. When a menstrual cycle is shorter or longer than 28 days, it’s the Follicular Phase that is altered. 166  Ovarian Cycle Corpus luteum may ▪ chart be oblong or irregular in shape, and contain Internal echoes (hemorrhage) corpus luteum https://radiopaedia.org/cases/corpus-luteum 167  Ovarian Cycle Menstrual cycle Ovarian cycle 168  Endometrial Cycle ▪ The varying levels of estrogen and progesterone throughout the length of the menstrual cycle induce characteristic changes in the endometrium ▪ These changes correlate with the ovarian cycle. 169  3 Phases Menstrual ENDOMETRIAL CYCLE Proliferative Secretory Copyright © 2016, Elsevier Inc. All Rights Reserved. 170  Endometrial Cycle Menstrual Phase ▪ The menstrual phase lasts approximately 1-5 days and begins with the declining progesterone levels causing the spiral arteries to constrict and break off. ▪ This causes a decrease in flow to the endometrium resulting in ischemia(tissue death) and shedding of the zona functionalis. ▪ During menses it is not uncommon to see varying levels of fluid and debris within the uterine cavity. ▪ Endometrium is thin and measures