الفهرس 
COVEROnly 14 pages are availabe for public view
 |  | from | 234 |  |  |
| | | from | 234 | | |
Abstract
This paper aimed at evaluation of the role of ultrasound and computed tomography in the assessment of acute pelvic pain in women.
Most studies define acute pain as having a duration of ≤ 3–6 months. Pain lasting six months or more is classified as chronic in nature.
Acute pelvic pain in a woman can be secondary to a variety of disorders, which may be difficult to differentiate on clinical grounds. This clinical conundrum is often solved by diagnostic imaging. Ultrasound is the imaging modality of choice in the young female patient presenting with acute pelvic pain.
The first step in the evaluation is to determine pregnancy status by measuring the serum β-HCG level. Next, the choice of the correct imaging test depends on the results of a careful clinical evaluation to narrow the differential diagnosis.
Transvaginal ultrasonography (TVUS) is the main stay of imaging evaluation at initial presentation. Itsstrengths include absence of radiation, rapid availability ofmachines in hospitals, and excellent visualization of the pelvic organs.
In the pregnant patient with pelvic pain or bleeding, an ectopic pregnancy must be first excluded. Ultrasound is important in determining the size and location of the ectopic pregnancy, and presence of bleeding, which in turn helps guide treatment decisions.
Subchorionic or subplacental bleeds in an intrauterine pregnancy may also present with vaginal bleeding with consequences dependent on gestational age and size of bleed.
In the postpartum female suspected to have retained products of conception, sonographic findings may vary from a thickened endometrial stripe to an echogenic mass with associated marked vascularity, often mimicking an arterial-venous malformation.
In the nonpregnant patient, early diagnosis and treatment of ovarian torsion can preserve ovarian functionOther causes of peritoneal irritation may also cause acute pelvic pain including a ruptured hemorrhagic cyst or ruptured endometrioma.When pelvic inflammatory disease is suspected, imaging is used to evaluate for serious associated complications including the presence of a tuboovarian abscess or peritonitis. It also provides a definitive diagnosis of ovarian hyperstimulation syndrome.
In the evaluation of obstetric and gynecologic causes of pain, TVS may be able to differentiate findings of hemorrhagic cyst or pelvic inflammatory disease, more compatible with medical management, from those more suspicious of ovarian torsion, a surgical emergency, and gestational findings of fetal distress or demise or placental abruption requiring urgent obstetrical management.
Transvaginal sonography (TVS) is able to detect the exact location, number, size and the echoarchitectural pattern of uterine fibroids. Leiomyomas of the uterus are largely asymptomatic, a leiomyoma that undergoes necrosis, torsion or prolapse through the cervix may be associated with acute severe pain or bleeding. The imaging features of these and other important clinical entities in the female pelvis will be presented.
The diagnosis of adenomyosis and endometriosis sonographically was possible by means of TVS before surgery.TVS has its greatest advantage in the detection of the presence and number of adnexal cysts, in addition to characterization of their internal echoarchitectural details as the presence of internal echoes, septations, reticulations, and fat-plug. Trans- abdominal sonography (TAS) is recommended when uterine and adnexal structures are beyond the field of view of the transvaginal probe. In addition, duplex and color or power Doppler imaging can be used to characterize the vascularity of the ovaries, adnexal structures, and uterus, information helpful in narrowing the field of differential considerations.
The main limiting factor for the use of TVS is the virginity &the relatively small field of view. It was not possible to obtain a panoramic or global view of the pelvis, therefore large masses that extend to the upper portion of the pelvic cavity was not adequately visualized, thus Transabdominal US was more beneficial in those cases.
For the performance and interpretation of the ultrasound study, correlation with the patient’sclinical history, physical findings, and laboratory tests arenecessaryWhether obstetric, gynecologic, gastrointestinal, urinary, or another etiology is most highly suspected will determine which pelvic imaging study is the most appropriate for accurate and expeditious diagnosis and triage.
Although gynecologic conditions constitute most causes of acute pelvic pain, particularly in women of childbearing age; non- gynecologic conditions should also be considered. These conditions may be easily overlooked and delay diagnosis.
Sometimes ultrasound can help diagnosenongynecologic disorders. Not only is sonography helpful from an imaging standpoint but also one can take advantage of direct patient contact during the examination to correlate the point of maximal tenderness with the underlying imaging findings.
Sonography should also be considered when gastrointestinal or urinary tract pathology is suspected in pregnant patients. Despite some diagnostic limitations, sonography has the advantage over CT of sparing the fetus ionizing radiation. In the diagnosis of appendicitis, TAS has demonstrated variable sensitivity and specificity. Unfortunately, the technique of graded compression required for this diagnosis is often not feasible in the presence of an enlarged gravid uterus. More important, a normal appendix is visualized in only 13% to 50% patients, even in the absence of pregnancy; as a result, a negative examination result cannot exclude the diagnosis of appendicitis. For diagnosis of obstructing ureteral calculi, a wide range of sensitivities (34%-95%) have been reported with sonography. Transvaginal sonography is recommended for the detection of distal ureteral calculi should the results of TAS prove inconclusive. Sonographic specificity is reduced by the physiologic urinary dilatation common in pregnancy. Nevertheless, normal results on renal sonography can be useful in excluding renal colic. The role of CT is still of great value not only as a primary imaging modality but also in those cases in which gynecologic exploration is undone since it is not the initial suspicion; US findings are equivocal or if the abnormality remains characterized in an incomplete way by theendovaginal or abdominal probes and further characterization is required.
The disadvantage of this technique is that the patient is exposed to large dose of radiation; also CT is relatively expensive in comparison to the TVS. Another disadvantage of CT is the necessity to oral preparation with contrast media and the hypersensitivity reactions to intravenous contrast media which would hinder its use in emergency cases.
Computed tomography demonstrates the best diagnostic performance in identifying the gastrointestinal and urinary tract causes of acute pelvic pain. It demonstrates high sensitivity and specificity in the diagnosis of appendicitis, even in pregnancy. Moreover, because CT almost always permits a normal appendix to be visualized, it is useful for reliably excluding the diagnosis of appendicitis.
Computed tomography is also the preferred modality for the detection of other bowel pathologies, such as inflammatory bowel disease, diverticulitis, and infectiousenteritis or colitis. Computed tomography without intra-venous contrast is more sensitive than sonography for the detection of ureteral calculi.
For the accurate diagnosis of pelvic venous thrombosis, and most bowel pathologies, intravenous contrast-enhanced CT is required for optimum accuracy.
Because CT is often the first-line imaging modality in the diagnosis of abdominal pain originating from bowel or the urinary tract, findings of gynecologic pathology have been documented in these studies. The diagnosis of a tubo-ovarian complex by the appearance of thick- walled, fluid-filled structures have proved to be useful. The milder inflammatory changes within the fallopian tube and adjacent fat may also be better appreciated on CT than ultrasound.
Common findings of ovarian torsion include thickening of the fallopian tube, smooth walled thickening of a cystic adnexal mass, ascites, uterine deviation to the twisted side, and infiltration of adjacent pelvic fat.
Despite its diagnostic utility, pelvic CT, whichdelivers ionizing radiation, should be selectively used in evaluating children and women in their reproductive years.