Methacholine challenge testing in Reserve Officer Training Corps cadets.

STUDY OBJECTIVE: To determine the prevalence of positive results for methacholine challenge tests in asymptomatic Reserve Officer Training Corps (ROTC) cadets with no history of asthma. DESIGN: Prospective, blinded cohort comparison study. SETTING: Pulmonary diseases clinic in a US Army tertiary-care medical center. PATIENTS: One hundred three college students who were undergoing a physical examination before entering active duty. Group 1 subjects, 58 men and 5 women with an average age of 22.7 years, had no symptoms or personal history of asthma. Group 2 patients, 34 men and 6 women with an average age of 22.2 years, had a history or recent suggestive symptoms of asthma. INTERVENTIONS: Methacholine challenge testing using concentrations of 0.025, 0.25, 2.5, 10, and 25 mg/mL for a total dose of 188 inhalation units or until FEV(1) had declined by 20%. RESULTS: Group 2 had significantly more patients with positive results for methacholine challenge tests or reversible airflow obstruction at baseline (23 of 40 patients [57.5%]) than group 1 (8 of 63 patients [12.7%]; p < 0.05). The cadets in group 1 with positive results for methacholine challenge tests reacted with a 20% decline in FEV(1) at the following concentrations: 25 mg/mL (188 IU), 2 patients; 10 mg/mL (64 IU), 4 patients; and 2.5 mg/mL (13.8 IU), 2 patients. Using values calculated for the provocative concentration of a substance causing a 20% fall in FEV(1) and the new American Thoracic Society criteria, four patients would have borderline bronchial hyperresponsiveness (4 to 16 mg/mL) and three patients (4.8%) would have mild bronchial hyperresponsiveness (1 to 4 mg/mL). CONCLUSIONS: Asymptomatic US Army ROTC cadets with no history of asthma have possible false-positive responses to methacholine at concentrations > 0.25 mg/mL.

Transrectal sonography in staging rectal carcinoma: the role of gray-scale, color-flow, and Doppler imaging analysis.

OBJECTIVE: The purpose of this study was to evaluate the efficacy of combining gray-scale sonography with color-flow imaging and pulsed Doppler transrectal sonography in the staging of rectal carcinoma. SUBJECTS AND METHODS: Thirty-nine patients with primary rectal carcinoma underwent transrectal sonography. The rectal masses were staged T1-T2 or T3-T4 on the basis of gray-scale imaging. The local nodes were classified as benign or malignant on the basis of size and echogenicity. In 22 patients, color-flow imaging and pulsed Doppler imaging of the rectal mass and of the local lymph nodes were performed. The peak systolic velocity (PSV) and end diastolic velocity were documented, and the resistive index was calculated. RESULTS: Gray-scale imaging alone was used to stage T1-T2 masses with 88% sensitivity and 82% specificity. T3-T4 masses were staged with 82% sensitivity and 88% specificity. Overall accuracy was 85%. Gray-scale imaging of lymph nodes using a discriminatory size of less than or equal to 5 mm for benign nodes and greater than 5 mm for malignant nodes yielded a sensitivity of 100%, a specificity of 28%, and an accuracy of 52%. Using receiver operating characteristic curve analysis, we determined that a size of greater than or equal to 7 mm was optimal for characterizing nodes. Such a size provided an accuracy of 83%. PSV of less than 25 cm/sec distinguished T3-T4 from T1-T2 rectal masses with 75% sensitivity, 80% specificity, and 77% accuracy. A PSV of greater than 20 cm/sec classified a node as malignant with 100% sensitivity, 62% specificity, and 76% accuracy. A resistive index of greater than 0.61 classified a node as malignant with 71% sensitivity, 85% specificity, and 80% accuracy. CONCLUSION: Color-flow imaging and pulsed Doppler imaging are useful additions to gray-scale transrectal sonography in staging primary rectal carcinomas. The combination has most value when evaluating perirectal nodes.

Doppler color flow imaging surveillance of deep vein thrombosis in high-risk trauma patients.

To determine the prevalence of upper and lower extremity deep vein thrombosis in high-risk trauma patients, 136 consecutive high-risk trauma patients were prospectively evaluated with weekly Doppler color flow imaging. Incomplete compressibility and visualized intraluminal thrombus were considered diagnostic of deep vein thrombosis. Pulmonary embolus was documented by pulmonary arteriography. Deep vein thrombosis occurred at 27 non-contiguous sites in 19 patients (14%). Eight of 27 cases of deep vein thrombosis (30%) involved the upper extremity and 19 (70%) occurred in the lower extremity. Twenty-one of 27 deep vein thromboses (78%) were partially occlusive, whereas six (22%) were occlusive. Pulmonary embolus was documented in three patients (2.2%). Doppler color flow imaging detected occult deep vein thrombosis in 14% of high-risk trauma patients (30% occurring in the upper extremity).

Quantitative Doppler assessment of acute scrotal inflammation.

PURPOSE: To establish quantitative Doppler criteria for acute unilateral epididymitis and/or orchitis. MATERIALS AND METHODS: Triplex ultrasonography (US) was used to prospectively evaluate 31 patients with acute hemiscrotal pain and 15 asymptomatic control subjects. Morphology and perfusion were assessed, and peak systolic velocities (PSVs) were recorded. Ratios of PSV were calculated by using values from the right and left sides. RESULTS: PSVs in control subjects differed significantly from those in patients (P < .0001). A PSV > or = 15 cm/sec produced diagnostic accuracy of 90% for orchitis and 93% for epididymitis: Five of six false-negative findings were in patients younger than age 15 years. Epididymal PSV ratios > or = 1.7 or testicular ratios > or = 1.9 were diagnostic of acute inflammation (P < .0001). In three cases, morphologic and color Doppler findings were normal and only the PSV ratios were diagnostic. CONCLUSION: PSV and PSV ratios provide diagnostic criteria for acute unilateral epididymitis and/or orchitis that are more accurate than morphologic evaluation and color flow imaging either alone or in combination.

Characterization of focal hepatic lesions with duplex sonography: findings in 198 patients.

OBJECTIVE: The purpose of this study was to determine the value of duplex Doppler sonography in the characterization of focal hepatic lesions. SUBJECTS AND METHODS: Duplex Doppler sonography with a 3-MHz transducer was performed prospectively on 198 patients with focal hepatic lesions. One hundred thirty-two patients had pathologically proved diagnoses, confirming 46 hepatomas and 86 metastatic lesions. Twenty-three hemangiomas were confirmed either with tissue, tagged RBC study, MR imaging, or hemangioma CT protocol. Forty-three patients with no history of cancer had benign lesions that were established on the basis of follow-up imaging and at least a 2-year clinical history with no evidence of cancer. RESULTS: Thirty-two hepatomas and four metastatic lesions had Doppler shifts of 4.5 kHz or more, giving a 70% sensitivity, 95% specificity, and 89% positive predictive value in distinguishing hepatomas from metastatic lesions. Forty-three hepatomas, 47 metastatic lesions, one hemangioma, and three benign lesions had Doppler shifts of 1.75 kHz or more, giving a 68% sensitivity, 94% specificity, and 96% positive predictive value in distinguishing malignant from benign lesions. Doppler shifts (mean +/- SD) were as follows: hepatomas, 4.72 +/- 1.72 kHz; metastases, 1.99 +/- 1.63 kHz; and hemangiomas, 0.53 +/- 0.75 kHz. These differences in mean Doppler shifts were statistically significant (p < .0001). CONCLUSION: Duplex Doppler sonography aids in distinguishing hepatomas from metastases and malignant from benign hepatic lesions with a high degree of specificity but low sensitivity.

Prospective ultrasound evaluation of venous thrombosis in high-risk trauma patients.

UNLABELLED: To determine the incidence of venous thrombosis (VT), high-risk trauma patients were evaluated prospectively biweekly with Doppler ultrasound (US). Fifty-seven patients during an 8-month period met high-risk criteria for VT including age > 45 years, > 2 days bed rest, previous history of thromboembolism, spine fracture, coma, spinal cord injury, pelvic fracture, lower extremity injury, or femoral vein catheter. Doppler ultrasound showed 16 VTs in 12 patients. Venous thrombosis occurred despite prophylaxis (heparin or compression devices) in 9 of 12 patients. Iliac VT was noted in four patients, two of whom had no lower extremity VT. Upper extremity VT occurred in two patients who had received central venous catheters. CONCLUSIONS: (1) US surveillance may be valuable in high-risk trauma patients because VT is a common finding (21%), despite prophylactic measures. (2) Examination of the upper extremity and pelvic venous system appears to be important, since 33% (4 of 12) of our patients with VT developed thrombi isolated to these regions. These would not have been identified during routine lower extremity duplex studies.

Ectopic pregnancy: evaluation with endovaginal color flow imaging.

Endovaginal sonography and endovaginal color flow imaging were compared in 155 patients with clinical suspicion of ectopic pregnancy. Sixty-five patients (42%) had surgically confirmed ectopic pregnancies. Thirty-six of the pregnancies were diagnosed with endovaginal sonography alone, the criteria being an extrauterine sac or ectopic fetus (sensitivity, 54%). Sixty-two ectopic pregnancies were diagnosed with endovaginal color flow imaging (sensitivity, 95%) when an ectopic fetus or sac was seen or placental flow was identified in an adnexal mass separate from the ovary and uterus. The diagnosis of ectopic pregnancy was excluded with endovaginal sonography (specificity, 98%) and endovaginal color flow imaging (specificity, 98%) by finding an intrauterine gestation, nonvisualization of an adnexal mass, and absence of placental flow. Three false-positive and three false-negative diagnoses were made with endovaginal color flow imaging (positive predictive value, 97%). The addition of color Doppler flow imaging to endovaginal sonography allows increased sensitivity in the detection of ectopic pregnancy.

Imaging of the testicle: the painful scrotum and nonpalpable masses.

Scrotal pain is initially evaluated by color Doppler ultrasonography providing information on the presence or absence of flow within the testis and B Scan imaging providing important complementary information about lesions such as torsion of the appendix testis and testicular abscess. While radioisotope scanning provides similar information to color Doppler about testicular flow, it does not demonstrate the anatomy. Testicular imaging is extremely sensitive for "silent masses" and useful to evaluate palpable ones. Characteristic findings may be seen with simple testicular cysts and epidermoid cysts. Homogeneously hyperechoic masses have a variety of etiologies but are virtually always benign. A major limitation of a ultrasonography is the large number of nonneoplastic lesions which may mimic tumors.

Doppler color imaging. Obstetric and gynecologic applications.

The addition of pulsed and color Doppler has greatly added to the diagnostic potential for obstetric and gynecologic ultrasound. In addition to improved morphologic detail inherent in the use of EVUS, new information is available on perfusion and the physiologic changes associated with the menstrual cycle and early pregnancy. The absence of luteal flow strongly predicts unsuccessful pregnancy outcome in patients undergoing therapy for infertility. This introduces the possibility of more economic use of expensive treatments. Later in pregnancy, DCI aids in the efficient and accurate performance of Doppler spectral sampling and contributes to the evaluation of structural and functional abnormalities of the fetus, umbilical cord, and placenta. Applications in the evaluation of patients with suspected ectopic pregnancy, incomplete abortion, and pseudosac are welcome additions for clinical problems that currently result in many malpractice suits. Finally, the recognition of neovascular flow, especially in the ovary, raises hope for improved and earlier diagnosis of ovarian cancer.

Early detection of ovarian cancer: background, rationale, and structure of the Yale Early Detection Program.

Ovarian cancer has received national attention as a highly virulent disease. Its lack of early warning symptoms and the failure to develop highly sensitive screening tests have led some physicians to recommend prophylactic oophorectomies to women with relatives who have had ovarian cancer. Others have recommended routine screening of otherwise normal women for CA 125, a circulating tumor marker, and ultrasound examinations. Each of these techniques is associated with substantial false-positive rates that could lead to unnecessary surgery. A review of epidemiologic data suggests that familial ovarian cancer kindreds are rare, but women with first-degree relatives who have had ovarian cancer have a significant risk themselves for developing ovarian cancer. In addition, women with a great number of ovulatory cycles are at an increased risk for the disease. Circulating tumor markers are frequently elevated in women with advanced ovarian cancer, but their value in early detection of ovarian cancer has yet to be established. Advances in endovaginal ultrasound and color Doppler flow technology have significantly improved our ability to assess pelvic organs. This article presents the background, rationale, and structure of the Yale Early Detection Program for ovarian cancer, whose goals are to identify the best techniques for diagnosing ovarian cancer in an early stage, to determine the frequency with which such tests should be employed, to assess false-positive results, and to identify women who might benefit from prophylactic oophorectomies.

Early detection of ovarian cancer: preliminary results of the Yale Early Detection Program.

Eighty-four women at high risk for ovarian cancer by having first-degree relatives with epithelial ovarian cancer participated in a newly established, early ovarian cancer detection program at Yale University. Participants were to be evaluated with physical examinations and circulating tumor markers at entry and every six months thereafter. Endovaginal ultrasound and color Doppler flow studies were to be performed at three and nine months following entry into the program. In addition, women were encouraged to follow American Cancer Society guidelines for mammography. Stool was checked for occult blood. Endometrial sampling was offered to post-menopausal women. No participant has developed an ovarian cancer since entering the program. One woman has been diagnosed to have breast cancer. False-positive levels of circulating tumor markers (CA 125, 4/84 [4.8 percent]; lipid-associated sialic acid in plasma, 13/84 [15.5 percent]; NB/70K, 4/84 [4.8 percent]; and urinary gonadotropin fragment, 1/65 [1.5 percent]) were observed on entry into the program. Low resistive indices (less than 0.5) were documented in 8/91 (8.8 percent) ovaries studied by the color Doppler flow technique. One participant underwent a laparotomy based on a false-positive endovaginal ultrasound examination. Tests now being employed in community practice have a high likelihood of being associated with false-positive results. Therapeutic interventions based on isolated abnormal tumor markers or ultrasound studies obtained from women with family histories of ovarian cancer may lead to inappropriate surgery. It is necessary for cancer centers to develop expertise in ovarian cancer detection techniques to advise physicians in their geographic areas appropriately about the significance of the abnormal screening test.

Comparison of platelet scintigraphy, impedance plethysmography gray scale and color flow duplex ultrasound and venography for the diagnosis of venous thrombosis.

The several techniques available for the diagnosis of venous thrombosis have not been directly compared in the same patient population. Thus color and gray scale duplex ultrasound (U), impedance plethysmography (IPG), 3-4 hr platelet imaging (PS) were compared to venography (V), in 104 consecutive patients (in hospital and out). PS and V were read by two, and IPG and U by one, blinded reader. Comparisons were made for the calf (CA), popliteal (Pop) and femoral (Fem) vessels. Reproducibility of V and PS was 84 and 87%. (table; see text) We conclude that PS, while having a very high specificity, has an unacceptably low sensitivity. However, while both impedance plethysmography and color flow ultrasound have excellent and similar diagnostic accuracy in the femoral, these techniques have either a low sensitivity or low technical success rate in the calf or popliteal veins.

Detection of renal masses: sensitivities and specificities of excretory urography/linear tomography, US, and CT.

A prospective blinded study of 201 patients was performed to determine the relative sensitivities and specificities of excretory urography/linear tomography (EU/LT) and ultrasound (US) for the diagnosis of renal parenchymal masses. Computed tomography (CT) was used as a standard. EU/LT permitted detection of 10% of CT-confirmed masses (cystic or solid) less than 1 cm, 21% of lesions greater than or equal to 1 cm but less than 2 cm, 52% of lesions greater than or equal to 2 cm but less than 3 cm, and 85% of lesions 3 cm or more in diameter. US permitted detection of 26% of CT-confirmed lesions less than 1 cm, 60% of lesions greater than or equal to 1 cm but less than 2 cm, 82% of lesions greater than or equal to 2 cm but less than 3 cm, and 85% of lesions 3 cm or more in size. The results confirm the relative insensitivity of EU/LT for masses less than 3 cm in diameter and of US for masses less than 2 cm. Further, they suggest that CT may have a role not only in evaluation of cases in which the urographic or sonographic results are questionable or positive, but also in confirmation of apparently negative urographic findings when clinical suspicion of a lesion is high.

Brachial plexus: correlation of MR imaging with CT and pathologic findings.

Thirty-two patients with symptoms referable to the brachial plexus were evaluated with magnetic resonance (MR) imaging. Sixteen patients had undergone concurrent computed tomography (CT). MR imaging demonstrated normal findings in 16, 12 neoplasms, three cases of trauma, and one case of possible neural edema. Of the 16 patients with normal findings on MR images, eight had CT scans that were also normal. In one patient, MR images showed that the "mass" seen on CT was actually a tortuous blood vessel. In six of the 12 cases of neoplasm in which CT scans were available, MR imaging revealed more extensive disease. In the other six cases of tumor, MR imaging provided sufficient clinical information to obviate the need for CT or any other imaging modality. MR imaging provided definitive diagnoses in the three cases of trauma without further imaging. In one patient with paresthesia, MR imaging showed high signal intensity of the nerves on T2-weighted images, which was compatible with neural edema. A concurrent CT scan was normal.

Pneumocystis carinii thyroiditis.

A 38-year-old black man with a history of acquired immunodeficiency syndrome associated with intravenous drug abuse presented with two weeks of left-sided neck swelling. Results of thyroid function tests were within normal limits. Thyroid scan demonstrated nonvisualization of the left lobe. Fine-needle aspiration of the thyroid revealed the presence of Pneumocystis carinii organisms in the thyroid tissue. Although chest radiography and computerized tomography of the chest detected several nodules and cavitary lesions, the results of bronchoalveolar lavage and transbronchial biopsy were negative for P. carinii. The patient showed a response to treatment with trimethoprim/sulfamethoxazole. Thyroidal involvement with P. carinii has previously been documented only in the setting of overwhelming, fatal pulmonary infection. The current case expands the clinical spectrum of extrapulmonary pneumocystosis and documents its successful treatment.

CT features of hemorrhagic malignant liver tumors.

Hemorrhage is a recognized occurrence in hepatocellular carcinoma but is infrequently seen with tumors metastatic to the liver. This complication was observed in three patients with primary hepatic malignancy and in four patients with hepatic metastases (melanoma, two; colon, one; breast, one) who were studied by CT. Hemorrhage occurred in the patient with metastatic colon carcinoma in the setting of anticoagulation. Definitive radiographic signs of hemorrhage were detected by CT in six of the patients, including hyperdense hepatic masses on noncontrast scans (four patients), high density peritoneal (one patient) and subcapsular fluid (one patient), and the hematocrit effect in peritoneal fluid (one patient). In three patients an irregular liver border adjacent to perihepatic fluid suggested the liver as the organ from which bleeding originated. There were four deaths, none of which was immediately related to the hemorrhagic complication.

Focal liver masses: differential diagnosis with pulsed Doppler US.

Duplex Doppler ultrasound (US) was used in 68 consecutive patients with focal liver lesions, including 12 hepatocellular carcinomas, one cholangiocarcinoma, 37 metastases, 15 hemangiomas, one hemangioendothelioma, and two focal nodular hyperplasias. Of the hepatocellular carcinomas, six were diffusely hyperechoic, two were hypoechoic, two were single hyperechoic lesions, and two were multifocal and hyperechoic. All ten tumors with Doppler shifts of 5 kHz or above proved to be hepatocellular carcinomas. The other two hepatocellular carcinomas showed Doppler shifts of 3 kHz. In contrast, no hemangioma showed shifts above 0.7 kHz, and ten of the 15 gave no detectable signal. Of the metastases, 20 gave no signal and 17 had signals of up to 4 kHz. Three-kilohertz signals were also obtained from a cholangiocarcinoma, a hemangioendothelioma, and focal nodular hyperplasia. Correlation with angiographic findings suggested that the high-velocity Doppler signals were associated with large pressure gradients due to arteriovenous shunting. Duplex Doppler US can therefore aid in the differential diagnosis of diffuse and focal liver lesions.

Superior mesenteric artery syndrome following ileal J-pouch anal anastomosis. An iatrogenic cause of early postoperative obstruction.

This is the first case report of the superior mesenteric artery syndrome developing in a patient following total proctocolectomy and ileal J-pouch anal anastomosis. In addition, this is the first demonstration of this syndrome using abdominal CT scan. A 22-year-old veteran underwent total proctocolectomy for left-sided ulcerative colitis because of failure of medical therapy. At operation an ileal J-pouch anal anastomosis was constructed. Following operation, the patient developed an intestinal obstruction. Abdominal CT scan demonstrated scant retroperitoneal fatty tissue, massive dilatation of the duodenum proximal to the midline, and tapered narrowing of the duodenum between the superior mesenteric artery and aorta. These findings indicated superior mesenteric artery syndrome: arteriomesenteric obstruction of the duodenum. Based on the experience of this case, the authors believe that compression of the duodenum by the superior mesenteric artery may be a common but unsuspected cause of prolonged postoperative ileus or early postoperative obstruction following ileal pouch anal anastomosis.