Sonographic appearance of benign and malignant conditions of the colon

OBJECTIVE

The objective of this study was to compare the sonographic appearance of different abnormalities of the colon to evaluate the role of sonography in their differential diagnosis.

MATERIALS AND METHODS

We retrospectively reviewed videotaped sonographic examinations of 99 patients with proven diagnoses that included diverticulitis (n = 35), malignancy (n = 20), Crohn's disease (n = 16), pseudomembranous colitis (n = 14), ischemic colitis (n = 9), and ulcerative colitis (n = 5). Data were collected with regard to gut features, including the site of colonic involvement, associated small-bowel involvement, length of diseased segment, stratification, luminal contents, pneumatosis, and diverticula. Perigut features evaluated included abnormal fat, abscess, fistula, and ascites.

RESULTS

On sonography, the following features were statistically significant (p < .05). Involvement of the small bowel was more common in patients with Crohn's disease than in the remainder of the study population (44% versus 1%). Left-sided colonic disease (91% versus 38%), diverticula (91% versus 3%), and perigut findings (91% versus 57%), including abnormal fat (83% versus 39%) and abscess (34% versus 8%), were features that indicated diverticulitis. Malignant conditions were more common in patients with a greater wall thickness (mean, 26.2 mm versus 10.2 mm), asymmetric involvement (85% versus 39%), loss of stratification (85% versus 20%), absence of perigut findings (65% versus 22%), and involvement of a short diseased segment (70% versus 16%). Involvement of the entire colon (50% versus 2%), luminal contents (64% versus 28%), and ascites (64% versus 26%) were features suggesting pseudomembranous colitis.

CONCLUSION

Although the sonographic appearances of abnormalities of the colon overlap, some sonographic features are helpful in the differential diagnosis of colonic abnormalities.

Role of endovaginal sonography in the diagnosis and management of ectopic pregnancy

Although diagnostic laparoscopy is still considered the standard reference in the diagnosis of ectopic pregnancy (EP), use of high-resolution endovaginal sonography, in conjunction with qualitative serum assays of the beta subunit of human chorionic gonadotropin (beta-hCG), allows detection of earlier and smaller EPs. The most common endovaginal sonographic finding of EP (89%-100% of cases) is an extraovarian, round or elongated, solid tubal mass. A tubal ring (an extrauterine saclike structure) is the second most common finding (40%-68% of cases). Pelvic fluid may be present, but it is a nonspecific finding. An EP may have a pseudosac, which can be distinguished sonographically from the true gestational sac of an intrauterine pregnancy. Color Doppler techniques can complement endovaginal sonographic findings, but they should be performed only after a thorough real-time evaluation of the adnexal region. Current therapeutic options for EP include expectant management (ie, close follow-up), medical treatment (usually injections of methotrexate), and surgery. Accurate diagnosis with endovaginal sonography is the prerequisite to nonsurgical management, since surgery is the logical treatment if laparoscopy is used for diagnosis.

Diffuse uterine adenomyosis: morphologic criteria and diagnostic accuracy of endovaginal sonography

PURPOSE

To determine the accuracy of endovaginal ultrasound (US) in the diagnosis of uterine adenomyosis and to evaluate the frequency of observed sonographic criteria.

MATERIALS AND METHODS

Endovaginal US was performed in 100 consecutive women undergoing hysterectomy for a variety of benign and malignant conditions. Adenomyosis was diagnosed when a poorly defined area of abnormal echotexture (decreased or increased echogenicity, heterogeneous echotexture, myometrial cysts) was present in the myometrium. All endovaginal US findings were correlated with those from histologic examination.

RESULTS

Endovaginal US depicted 25 of 29 pathologically proved cases of adenomyosis. Adenomyosis was correctly ruled out in 61 of 71 patients. Endovaginal US had a sensitivity of 86%, a specificity of 86%, and a positive and negative predictive value of 71% and 94%, respectively. Of the 25 patients with true-positive findings at US, the myometrium demonstrated heterogeneous and hypoechoic areas with or without the presence of cysts in 21 (84%) patients, hypoechoic areas with cysts in three (12%) patients, and heterogeneous areas within the myometrium in one (4%) patient.

CONCLUSION

Adenomyosis of the uterus can be accurately diagnosed with endovaginal US with use of specific sonographic criteria.

Endovaginal sonographic appearance of benign ovarian masses

This article illustrates the different appearances of benign ovarian and paraovarian masses at endovaginal sonography. A retrospective study was performed of the records for 118 patients with 140 surgically proved benign adnexal masses, including dermoid cysts (n = 27), endometriomas (n = 40), epithelial inclusion cysts (n = 14), serous cystadenomas (n = 11), mucinous cystadenomas (n = 14), fibromas (n = 11), cystadenofibromas (n = 12), paratubal cysts (n = 5), hydrosalpinges (n = 3), and tubo-ovarian abscesses (n = 3). Preoperative diagnosis was made in 96% of the dermoid cysts on the basis of a hyperechoic attenuating component or multiple small horizontal interfaces and in 100% of uncomplicated fibromas on the basis of a hypoechoic attenuating mass. There was an overlap among the endovaginal sonographic appearances of the other condition.

Accuracy of endovaginal sonography for the detection of fallopian tube blockage

The patency of 814 fallopian tubes in 414 patients was evaluated by endovaginal sonography immediately prior to hysterosalpingography. In the 659 fallopian tubes that were normal with free spillage, endovaginal sonography did not reveal any tubal or peritubal abnormality (specificity 100%). Of the 64 fallopian tubes with definite hydrosalpinx on hysterosalpingography, only 22 were detected on endovaginal sonography (sensitivity 34%). Four of 57 (7%) fallopian tubes with definite proximal blockage on the hysterosalpingogram showed hydrosalpinx on the same side on endovaginal sonography, indicating the association of proximal and distal tubal blockages in a small group of patients with blocked fallopian tubes. This combination can only be detected by the addition of endovaginal sonography to hysterosalpingography. Ten of 11 (91%) hydrosalpinges in seven patients who underwent endovaginal sonography immediately after hysterosalpingography were detected by ultrasonography. Only two of these had been visible on pre-hysterosalpingography endovaginal sonograms. This would indicate that the poor sensitivity of endovaginal sonography for diagnosing hydrosalpinx is at least partly due to its lack of distention. We conclude that an abnormal endovaginal sonogram is highly predictive of the presence of a blocked tube, but endovaginal sonography has a poor sensitivity for the diagnosis of a hydrosalpinx detectable by hysterosalpingography. Endovaginal sonography would be useful to detect a combination of proximal and distal blockage in a subgroup of patients with tubal blockage.

Transvaginal US appearance of endometrial abnormalities

A retrospective study was performed on a series of 44 patients who had undergone transvaginal ultrasound (US) before hysterectomy. The surgically proved endometrial abnormalities included cystic atrophy, cystic and adenomatous hyperplasia, polyps, and malignancy. The following endometrial findings were evaluated: endometrial thickness, echogenicity, smoothness or irregularity of the contour, definition of the contour, and the presence of cystic areas. Some overlapping features were present between the benign and malignant conditions. Although cystic changes were seen in 76% of benign conditions manifesting with endometrial thickening, cystic changes were also present in 24% of endometrial malignancies. In the majority of endometrial malignancies, the endometrial contour was poorly defined, but 40% of the cases manifested as well-defined endometrial thickening. Most endometrial carcinomas (88%) were either diffusely or partially echogenic, 12% were isoechoic, and there was no endometrial carcinoma that was purely hypoechoic. Although the presence of cystic changes favors a benign condition, malignancy cannot be reliably excluded. Malignancy should be considered in the presence of a poorly defined, irregular endometrium. Transvaginal US has a significant role in the assessment of the endometrium, and although it can help in the differentiation between some benign and malignant conditions, there remain some overlapping features.

Intrahepatic portal venous system: variations demonstrated with duplex and color Doppler US

Seventeen cases of variations of the intrahepatic portal venous system were investigated with use of duplex and color Doppler ultrasound (US). Seven cases involved absence of the horizontal segment of the left portal vein, with portal supply to the left lobe arising from the right lobe. The 10 remaining cases involved variations of intrahepatic portal branching resulting from absence of the right portal vein, taking four patterns. It is thought that these findings represent variants of normal. These variants are important in two settings: in planning hepatic surgery and in the differential diagnosis of chronic portal vein thrombosis.

Evaluation of six new 99mTc-IDA agents for hepatobiliary imaging

IDA derivatives of three substituted benzothiazol, and two substituted chlorophenyl and one substituted pyrazoline compounds have been labeled with 99mTc and screened with four rat models with hepatocellular dysfunction manifesting varying degrees of change of liver architecture and hepatocellular damage associated with an active parenchymal destruction, fatty metamorphosis and cirrhosis. Organ distribution studies at 1 h postinjection have been compared in normal and diseased animal models for each agent labeled with 99mTc and with 99mTc-Disofenin (Disida) and Lidofenin (Hida) and 131I-Rose Bengal. From the data obtained with the six new IDA derivatives, the distribution kinetics of 99mTc-Arclophenin, (N-N'-2-benzoyl-4-chlorophenyl)carbamoylmethyl) imino diacetic acid (Phenida), are closely comparable to 99mTc-Disofenin in all animal models. Crossover patient studies (n = 14) for clinical evaluation of 99mTc-Arclophenin vs 99mTc-Disofenin indicate the close similarity of the 2 agents with regard to blood pool retention, gross liver/heart ratios and liver washout, suggesting Arclofenin as a suitable agent for hepatobiliary function studies. The impaired hepatocellular animal models presented should serve for fast screening of hepatobiliary agents and enable comparison of a series of closely related compounds.

Radiophosphate evaluation of loose hip prostheses

There were 23 patients who had revisions of their failed hip arthroplasties and a prior radiophosphate assessment of the joint components. In this selected group of patients the true positive incidence of abnormal scintigraphic findings for femoral component loosening was 19 out of 20 (95%) and the true negative incidence was two out of two by the criteria adopted. The true positive incidence of such findings, indicating acetabular component loosening, was seven out of seven, and the true negative was nine out of 10. Some of these patients also had contrast arthrography and the incidences of true positive and true negative findings for femoral component loosening were seven out of 15 (47%) and one out of one, respectively. Prediction of the status of the acetabulum was poorer using this technique with true positive and true negative incidences of four out of nine and two out of five, respectively.

Combined radionuclide and radiocontrast arthrography for evaluating hip arthroplasty

Twenty-two patients had combined radiographic and radiocolloid arthrography. The two procedures were in agreement in 86% of the patients as to whether the femoral component was loose or not. Fourteen patients has surgical revision of the prosthesis and in 3 (23%) radiographic arthrography was falsely negative. No false negative results were obtained with radiocolloid arthrography thus far. The radionuclide method cannot be used to assess the acetabular component.