You are in: eMedicine Specialties > Radiology > OBSTETRICS/GYNECOLOGY Polycystic Ovarian Disease (Stein-Leventhal Syndrome)Article Last Updated: Aug 23, 2007AUTHOR AND EDITOR INFORMATIONSection 1 of 9
  Author: Greg Marrinan, MD, Staff Physician, Department of Radiology, Bridgeport Hospital Greg Marrinan is a member of the following medical societies: American College of Radiology, American Medical Association, American Roentgen Ray Society, North American Society for Cardiac Imaging, and Radiological Society of North America Coauthor(s): Marjorie Stein, MD, Clinical Assistant Professor of Radiology, Albert Einstein College of Medicine; Consulting Staff, Department of Radiology, Montefiore Medical Center Editors: Christopher L Sistrom, MD, Associate Chair for Research, Assistant Professor, Department of Radiology, University of Florida School of Medicine; Bernard D Coombs, MB, ChB, PhD, Consulting Staff, Department of Specialist Rehabilitation Services, Hutt Valley District Health Board, New Zealand; Karen L Reuter, MD, FACR, Professor, Department of Radiology, Lahey Clinic Medical Center; Robert M Krasny, MD, Consulting Staff, Department of Radiology, The Angeles Clinic and Research Institute; Eugene C Lin, MD, Consulting Staff, Department of Radiology, Virginia Mason Medical Center Author and Editor Disclosure Synonyms and related keywords: polycystic ovaries syndrome, polycystic ovary disease, Stein-Leventhal syndrome, sclerocystic disease of the ovaries, microcystic degeneration, polyfollicular ovarian disease, enlarged ovaries, amenorrhea, hirsutism, anovulation, PCOD, PCOS INTRODUCTIONSection 2 of 9
  BackgroundIn polycystic ovary disease, enlarged ovaries with thickened sclerotic capsules and an abnormally high number of follicles are present. The follicles may concurrently exist in varying states of growth, maturation, or atresia. Although a multiplicity of clinical presentations exists for polycystic ovary disease, in 1935, Stein and Leventhal reported the classic symptomatology in a group of women who had amenorrhea, infertility, hirsutism, and enlarged polycystic ovaries.1 The authors found that, after ovarian biopsy, the women began to menstruate regularly. As was discovered over time, women may have polycystic ovaries, yet their cases may not conform to all of the original criteria for this condition. Therefore, Stein-Leventhal syndrome became a subgroup of a more encompassing disease called polycystic ovary disease. As more information regarding the nature of the condition has come to light, other terms have been applied, including polycystic ovarian/ovaries syndrome and polyfollicular ovarian disease. In actuality, polycystic ovaries are not the primary cause of amenorrhea or hirsutism in this condition. Rather, they are simply one sign of an underlying endocrinologic disorder that ultimately results in anovulation. For excellent patient education resources, visit eMedicine's Women's Health Center. Also, see eMedicine's patient education articles Ovarian Cysts, Amenorrhea, and Female Sexual Problems. PathophysiologyThe pathophysiology of polycystic ovarian syndrome is a highly debated and complex topic. A full discussion of the underlying endocrinologic alterations is far beyond the scope of this article; however, a brief discussion of the currently accepted model may suffice. In the normal state, the hypothalamus secretes gonadotropin-releasing hormone (GnRH) in a pulsatile manner. The pituitary gland responds to GnRH by releasing luteinizing hormone (LH) and follicle-stimulating hormone (FSH) in a similar cycle. In the follicular phase of the menstrual cycle, LH acts primarily on the theca cells of the ovary to increase the production of androgenic precursors. Concurrently, FSH acts on the granulosa cells to promote conversion of the androgens into estrogens, particularly estradiol, which assists in follicular development. During the follicular phase, increasing levels of estradiol lead to an LH surge. In a complex interaction, the LH surge, the elevated levels of estradiol, and an increase in the circulating progesterone level trigger the midcycle surge of FSH. In polycystic ovarian syndrome, the above cycle is disturbed. Any of several possible precipitating factors may contribute to the imbalance. Evaluation of blood serum levels typically reveals elevated LH levels and normal or low FSH levels. Patients also have increased levels of free estrogen, primarily estrone and estradiol. Estrogens exert a complex feedback effect on the pituitary gland that results in the suppression of FSH secretion and the increased release of LH. Thus, the production and release of androgen precursors by ovarian theca cells is increased. The peripheral conversion of androgens to estrogens, primarily estrone, strengthens the feedback effect on the pituitary gland. The same androgens also inhibit the production of sex hormone-binding globulin in the liver, indirectly increasing levels of free estrogen in the bloodstream as well. Locally, elevated androgen levels in the ovary exert a direct inhibitory effect on follicular maturation. In conjunction with the diminished but steady presence of FSH, the follicles continue to develop without ever maturing. Thus, numerous follicles are present in the polycystic ovary and show varying phases of development and atresia. The proposed causes of polycystic ovarian syndrome are numerous and may, in fact, be multiple. They vary from increased androgen production by the adrenal glands at puberty or times of stress to disturbances in the cyclic pattern of GnRH release by the hypothalamus. Several studies have revealed an inherited form of the disease that appears to exhibit autosomal dominant transmission with incomplete penetrance. Clearly, the pathophysiology of this disease is complex, and much remains to be learned about it. FrequencyInternationalThe prevalence of polycystic ovaries is difficult to accurately quantify. The inclusion criteria of most studies limit participants to those with specific clinical symptoms or syndromes and thus preclude a full accounting. In other studies, control subjects without polycystic ovaries often have symptoms that are associated with polycystic ovarian syndrome. Thus, a dilemma of nomenclature surrounds this clinical entity. Most authors agree that polycystic ovaries are present in 3-7% of women worldwide. Almost 75% of women with irregular menses and/or infertility may have polycystic ovaries, as determined with both radiologic and biochemical criteria. Polycystic ovaries have been found with ultrasonography in more than 50% of women with regular menstrual cycles as well; however, most of these women had some degree of hirsutism, acne, or male-pattern baldness. Mortality/Morbidity
SexPolycystic ovarian disease occurs only in females. Age
AnatomyThe normal adult ovary measures approximately 3-5 cm in length, 1.5-3 cm in width, and 0.5-1.5 cm in thickness; however, ovarian size is reported more often in terms of volume, or length × width × thickness × 0.523. Normal ovarian volume in the menstruating females is 5-15 mL, with an approximate mean of 10 mL; however, measurements as high as 22 mL have been reported in normal ovaries. A thin, fibrous layer, called the tunica albuginea, encapsulates the ovary. Within the capsule lies the ovarian stroma, a combination of fibroblasts, smooth muscle cells, arteries, veins, lymphatics, nerves, and follicles. The stroma is typically divided into a cortex and medulla. The medulla is a highly vascular region that is supplied by the ovarian artery and branches of the uterine artery, which enter the ovary via the broad ligament. From here, smaller arteries and arterioles penetrate the cortex. The peripheral zone, or cortex, is predominantly composed of follicles and spindle-shaped fibroblasts and smooth muscle cells. In women with female fetuses, by the seventh month of gestation, primordial follicles have begun to develop in the fetal ovary. They consist of primary oocytes that are encapsulated by single layers of follicular cells. At birth, each ovary contains approximately 400,000 primordial follicles. After puberty and during each ovarian cycle, a number of follicles are hormonally stimulated to begin maturing. Usually, only a single follicle completes the process. Follicular cells proliferate and differentiate into the granulosa cell layer. The surrounding ovarian stroma differentiates into thecal cells (internal and external layers). Cell layers play a complex role in the development of the follicle; in hormonal variations during the menstrual cycle; and, ultimately, in ovulation. Clinical DetailsMost patients in whom polycystic ovarian syndrome is ultimately diagnosed initially present with infertility, amenorrhea, or irregular menses. Although most woman present in their 20s or 30s, polycystic ovarian disease can affect females of any age, from menarche to menopause. Findings in almost 75% of patients meet the radiologic criteria for polycystic ovarian syndrome. Primary amenorrhea is a well-known but uncommon presentation. Although infertility is the most common presentation in affected patients, polycystic ovarian syndrome may be associated with obesity and insulin resistance, among other symptoms. A number of patients are identified only when they present with unrelated complaints; these patients may believe the symptoms that are associated with the syndrome are not of sufficient clinical significance to warrant medical attention. A second population of patients presents with systemic signs of androgen excess—namely, hirsutism, acne, or male-pattern baldness. In approximately one half of the patients, sonograms show polycystic ovaries. Additionally, a significant number of patients with unrelated complaints are incidentally found to have polycystic ovaries. Further detailed clinical evaluation reveals that approximately one half of the patients in this group have typical signs and symptoms of the syndrome (ie, hirsutism, acne, infertility) and that one quarter have related symptoms such as obesity, irregular menses, or insulin resistance. The remaining one quarter of the patients may not have any clinically evident abnormality. Preferred ExaminationPolycystic ovaries are most often diagnosed by means of laboratory studies. The initial screening tests may include determinations of the blood serum levels of thyroid-stimulating hormone (TSH), FSH, LH, and prolactin (PL). The ratio of the FSH level to the LH level is useful in the diagnosis. TSH or PL levels may be useful in identifying an etiology, such as hyperthyroidism or a prolactinoma. In some patients, testosterone and dihydroepiandrosterone sulfate (DHEAS) levels or a progesterone challenge are useful. Typically, a radiologic evaluation for polycystic ovaries is reserved for patients who have equivocal laboratory findings. However, radiologists make a significant number of incidental diagnoses. Should the radiologist's assistance be requested in the diagnosis of polycystic ovarian syndrome, the imaging method of choice is transabdominal and/or transvaginal ultrasonography. Magnetic resonance imaging (MRI) is useful as an adjunct; however, although MRI is more sensitive than ultrasonography, its findings are less specific. Polycystic ovarian syndrome is not a primary disease process. When polycystic ovaries are discovered at radiologic examination, further diagnostic tests are needed to determine the etiology. Limitations of TechniquesWhen the laboratory values are interpreted together with a thorough history as well as physical examination findings, they are useful in the diagnosis of polycystic ovaries. In some patients, such information may lead to a specific cause of the ovarian dysfunction (eg, hyperprolactinemia). When hormone levels do not provide adequate information, ultrasonography may prove useful; however, in the absence of correlative information, the significance of the radiologic findings is difficult to determine. The primary limitation of ultrasonography is that a radiologic diagnosis of polycystic ovaries does not reveal the underlying pathology, if it exists. Further studies are usually necessary to determine the cause of the radiologic finding. DIFFERENTIALSSection 3 of 9
Endometrioma/Endometriosis Pituitary Adenoma Other Problems to Be ConsideredVirilizing tumor, adrenal or ovarian RADIOGRAPHSection 4 of 9
FindingsSee Introduction, Preferred Examination above. MRISection 5 of 9
FindingsOvaries can be identified on MRIs in more than 95% of premenopausal women. On T1-weighted images, the ovaries have homogeneously low signal intensity, and they are easily distinguished from the surrounding pelvic fat. T2-weighted images reveal high signal intensity within the fluid-filled follicles of the ovarian cortex. The ovarian stroma remains dark on these images. Polycystic ovaries are characterized by numerous, small (<1 cm), peripheral cysts that are located throughout the cortex. The ovaries may be slightly larger than normal; however, the ovarian stroma is hypertrophic. Often, the fibrous capsule surrounding the ovary is prominent. Degree of ConfidenceAlthough MRI is sensitive to the presence of follicular cysts, this modality is not specific enough to permit the diagnosis of polycystic ovarian disease without corroborating laboratory values and features from the patient's history. False Positives/NegativesGreater experience is necessary before sufficient criteria can be determined for the diagnosis of polycystic ovarian disease. Changes seen in polycystic ovaries have also been noted in patients without polycystic ovarian syndrome, in patients with oligomenorrhea without a diagnosis of polycystic ovaries, and in patients taking exogenous steroids or clomiphene. The diagnosis remains a clinical one. ULTRASOUNDSection 6 of 9
FindingsPolycystic ovaries typically exhibit 3 characteristics on ultrasonographic examination: bilateral enlarged ovaries, multiple small follicles, and increased stromal echogenicity. Usually, the ovaries are enlarged symmetrically, and the shapes change from ovoid to spherical. Ovarian volume can increase by as much as 6 mL; however, almost 30% of patients with a biochemical and pathologic diagnosis of polycystic ovaries have no increase in ovarian volume. The typical polycystic ovary contains numerous follicles at any given time. The follicles are small (0.5-0.8 cm), and no dominant follicle is present. Characteristically, the follicles are peripherally located in the cortex; however, they can occur anywhere in the ovarian parenchyma. The diagnosis of polycystic ovaries should be reserved for patients with at least 5 of these follicles in each ovary. Typically, the ovaries are hypoechoic in relation to the surrounding pelvic fat and myometrium. Polycystic ovaries often display increased echogenicity; however, as many as one third may remain isoechoic or hypoechoic relative to the myometrium. Degree of ConfidenceUltrasonography has a largely corroborative role in the diagnosis of polycystic ovarian syndrome. In a patient with a biochemical diagnosis of polycystic ovaries, ultrasonographic findings may confirm the clinical diagnosis, but they cannot exclude it. Alternatively, the incidental discovery of polycystic ovaries during ultrasonography is not a reliable indicator of polycystic ovarian syndrome. False Positives/NegativesAlmost 30% of patients with endocrinologic findings of polycystic ovaries may have normal-sized ovaries on sonograms. Less than 50% of patients with biochemical features of polycystic ovaries and increased ovarian volume have the classic finding of multiple, small, peripheral follicles. Ultimately, the diagnosis should be made on clinical and biochemical grounds. However, normal ultrasonographic findings should not exclude the diagnosis. Alternatively, when polycystic ovaries are an incidental radiologic finding, approximately 25% of the patients have no clinical abnormality. Whether these patients have polycystic ovarian syndrome remains a matter of debate. Again, correlation with biochemical and clinical findings is necessary before a definitive diagnosis is made. INTERVENTIONSection 7 of 9
Medical/Legal Pitfalls
Special Concerns
MULTIMEDIASection 8 of 9
REFERENCESSection 9 of 9
Polycystic Ovarian Disease (Stein-Leventhal Syndrome) excerpt Article Last Updated: Aug 23, 2007 | ||||||||||||||||||||||||||||
