A fetal lung lesion consisting of bronchogenic cyst, bronchopulmonary sequestration, and congenital cystic adenomatoid malformation: the missing link?

A fetus was found to have a large left thoracic cyst on routine prenatal ultrasound at 23 weeks of gestation. This lesion caused compression of the normal left lung tissue and contralateral mediastinal shift. At 23 weeks of gestation the cyst was percutaneously aspirated without subsequent reaccumulation of fluid. Serial ultrasounds showed decrease in the size of the cyst. The clinical diagnosis of congenital cystic adenomatoid malformation was made. At birth, the child had no respiratory distress, and a CT scan confirmed the finding of a fluid-filled cyst in the left chest. At the time of resection, a nonaerated extralobar bronchopulmonary sequestration (with a systemic arterial blood supply and separate pleural investment) was found. The dominant cyst had ciliated respiratory epithelium with cartilage, indicative of a bronchogenic cyst, and the remainder of the specimen had the histologic hallmarks of a congenital cystic adenomatoid malformation. The coexistence of three separate anomalies in one lesion suggests a common embryological link for these malformations.

Defining the learning curve for the Focused Abdominal Sonogram for Trauma (FAST) examination: implications for credentialing.

Focused Abdominal Sonogram for Trauma (FAST) examination is being used increasingly for the torso evaluation of injured patients. In a controlled setting using peritoneal dialysis patients as models for injured patients with free fluid we hypothesized that more experienced providers would perform FAST with greater accuracy. Twelve fellow or attending level trauma surgeons, two radiologists, and one ultrasound technician were studied for their ability to detect intraperitoneal fluid (0-1600 cm3) in nine peritoneal dialysis patients with two different volumes of dialysate/patient. FAST experience with injured patients was defined as minimal (<30 patients examinations), moderate (30-100), or extensive (>100). All surgeons had participated in a didactic/practical course before the study. Test results were reported as "+" or "-" by the participant; "+" results were further quantified by volume. The sensitivity of those in the minimal-, moderate-, and extensive-experience to detect <1 L was 45, 87, and 100 per cent, respectively; the accuracy in detecting dialysate volume within 250 cm3 was 38, 63, and 90 per cent, respectively. In this controlled setting the accuracy of FAST particularly in diagnosing smaller volumes, as well as the ability to quantify volume, improves with experience. The learning curve for FAST starts to flatten out at 30 to 100 examinations. Training and credentialing policies should consider these findings to optimize patient care.

Percutaneous radiofrequency ablation of liver tumors with the LeVeen probe: is roll-off predictive of response?

PURPOSE: The LeVeen radiofrequency (RF) probe uses roll-off of electrical impedance as the endpoint for RF cautery of hepatic tumors. The purpose of this study is to determine the relation of roll-off to local control of hepatic tumors. MATERIALS AND METHODS: Twenty hepatic tumors, including 10 hepatomas and 10 metastases, were treated. Lesions ranged from 1.4 cm to 6.0 cm in diameter; 13 (57%) were smaller than 3.0 cm. Each lesion was ablated with use of the LeVeen 15-gauge RF needle according to the manufacturer's protocol. Five patients underwent chemoembolization the day before. Patients were followed up with contrast-enhanced computed tomography or magnetic resonance imaging at 1 month and every 3 months thereafter. RESULTS: Among the 20 lesions, roll-off was achieved at all burn locations in 11 (55%), no burn locations in eight (40%), and two of three burn locations in one (5%). Roll-off was observed in all patients who had undergone chemoembolization the day before. Six local recurrences occurred, five after RF ablation without roll-off and one after RF ablation with roll-off. According to life-table analysis, the local recurrence rate at 6 months without roll-off was 43% and with roll-off was 15% (P =.024; OR = 8.3; 95% CI = 0.93-66). CONCLUSION: Roll-off is a significant predictor of local control after RF ablation. Strategies to enhance roll-off, such as concurrent embolization, may be important to optimize the therapeutic effect of this device.

Sonographic appearance of focal thyroiditis.

OBJECTIVE: The purpose of this study is to report the sonographic appearance of focal thyroid nodules that prove to be lymphocytic thyroiditis on fine-needle aspiration. CONCLUSION: In a patient population undergoing sonography for palpable nodular disease without known thyroiditis, focal nodules of thyroiditis had a wide variety of appearances. They most commonly appeared as solid hyperechoic nodules with ill-defined margins. However, the echogenicity was variable, and calcification and cystic-appearing regions were also noted. The vascularity of these nodules as assessed with color Doppler and power Doppler sonography also varied widely. Biopsy of these lesions is still necessary because there are no sonographic features that can reliably diagnose these lesions as thyroiditis and differentiate them from other lesions.

The costs of CT procedures in an academic radiology department determined by an activity-based costing (ABC) method.

PURPOSE: The purpose of this work was to determine the costs of computed tomography (CT) procedures in a large academic radiology department, including both professional (PC) and technical (TC) components, by analyzing actual resource consumption using an activity-based costing (ABC) method and comparing them with Medicare payments. METHOD: Over a 12 month period from July 1, 1996, to June 30, 1997, 1,011 CT procedures, representing 16 Physicians' Current Procedural Terminology (CPT) codes and 98.3% of CT studies performed, were carefully observed by a research assistant trained in ABC methodology. Information collected during these time and motion studies included personnel/machine time and direct materials used. Actual resource units used during the different activities in each CT procedure were valued using appropriate cost drivers. Unit values for both direct and overhead costs were calculated: the cost of an individual procedure equaled the sum of component costs. Costs were compared with PC and TC payments according to the 1997 Medicare Fee Schedule. RESULTS: Total costs of CPT codes 70450 (CT Head unenhanced), 71260 (CT Chest enhanced), and 74160 (CT Abdomen enhanced), which represented 71.2% of CT studies performed, were $189.19, $273.53, and $343.20, respectively. For all 16 nonmodified CPT codes analyzed, Medicare's professional reimbursement was less than the professional cost, whereas its technical reimbursement exceeded respective cost in 14 of the 16 codes. CONCLUSION: In the setting and time period studied, Medicare underreimbursed professional costs while overreimbursing technical costs.

Sonography during early pregnancy: dependence of threshold and discriminatory values on transvaginal transducer frequency.

OBJECTIVE: Our goal was to determine if normal and abnormal pregnancies could be distinguished at smaller sac sizes with a higher frequency transvaginal transducer than with a 5-MHz transducer. SUBJECTS AND MATERIALS: Thirty-nine patients with potentially abnormal pregnancies identified with a 5-MHz transvaginal transducer were immediately reimaged with a 9-5-MHz transducer. We compared our ability to visualize the yolk sac, embryo, and cardiac activity relative to mean sac diameter on imaging at both frequencies in women with normal and abnormal pregnancies. RESULTS: Of the 39 pregnancies, 22 (56%) were normal or probably normal. Using the 5-MHz transducer, a yolk sac was first seen in a 6.4-mm gestational sac but was not definitively seen in 12 gestational sacs measuring 5-13 mm. Using the 9-5-MHz transducer, yolk sacs were identified in all gestational sacs measuring 4.6-13 mm, and live embryos were seen in five of eight sacs measuring 8.1-13 mm. The largest normal gestational sac without a live embryo measured 11 mm. When we compared these pregnancies with 17 (44%) abnormal pregnancies, we found that all pregnancies that had no yolk sac by the time the gestational sac measured 5.0 mm or no live embryo by 13 mm had abnormal findings on higher frequency imaging. CONCLUSION: The ability to visualize the yolk sac and embryo in early pregnancy is critically dependent on transvaginal transducer frequency. Threshold values and discriminatory sizes used to distinguish normal and abnormal pregnancies are smaller on higher frequency than on lower frequency imaging and, therefore, should be redetermined for specific transducer frequencies.

Image-guided fine-needle aspiration of the head and neck: five years' experience.

OBJECTIVE: To evaluate the diagnostic utility of image-guided fine-needle aspiration (FNA) in the head and neck. DESIGN: All image-guided FNAs of the head and neck performed January 1992 through June 1997 were included. All cytohistopathologic data were reviewed and collated. A slide review was performed in all cases with cytohistologic discrepancies. SETTING: The Department of Radiology, University of Pennsylvania Medical Center, Philadelphia. PATIENTS: Patients with deep-seated or poorly localized masses in the head and neck, representing both primary or recurrent/metastatic lesions, were referred. RESULTS: There were 111 computed tomography-guided FNAs performed in 109 patients. Sites sampled included parapharyngeal (n = 20), parotid or submandibular (n= 25), thyroid (34), and neck, paratracheal/paraesophageal, skull base, and paraspinal (n = 32). Diagnostic samples were obtained in 93 cases (83.8%). The procedures were well tolerated, without long-term complications. Cytologic examination detected a total of 39 malignancies, 24 of which were confirmed histologically. Eleven of the remaining malignant FNA cases reflected recurrent tumor; there were 3 false-positive FNA cases (2.7%), 2 in the setting of previous surgery and/or radiation therapy. There were 2 false-negative aspirates from sites deep in the neck (1.8%) among 7 of the 35 patients with benign aspirates who underwent surgery. Twenty six patients underwent ultrasound-guided FNA (thyroid gland only), revealing 1 papillary carcinoma and 1 intrathyroidal parathyroid gland, both of which were confirmed histologically. The findings in the aspirates from the rest of the patients were benign (n = 18), Hurthle cell neoplasm (n = 1), and nondiagnostic (n = 5). CONCLUSIONS: (1) The cytologic findings were supported clinically and/or histologically in 86 (92%) of the 93 diagnostic computed tomography-guided FNA cases. (2) Unnecessary surgery was avoided in 37% of the patients with recurrent tumor or benign diagnoses by cytologic assessment. (3) Potential pitfalls include false-positive diagnoses after radiation therapy and procedural or sampling limitations for deep neck and paraspinal lesions.

Sonography of transjugular intrahepatic portosystemic shunts: detection of elevated portosystemic gradients and loss of shunt function.

PURPOSE: To evaluate the role of ultrasound (US) in the detection of elevated portosystemic gradients and loss of shunt function in patients with a transjugular intrahepatic portosystemic shunt (TIPS). MATERIALS AND METHODS: The authors' prospectively compared 151 Doppler hepatic sonograms with follow-up portal venograms in 64 patients with TIPS. Sonographic data from within the portal system, hepatic arteries, and three areas within the TIPS were collected. Statistical analysis of these parameters was used to establish the US criteria for shunt dysfunction. RESULTS: Midshunt velocity thresholds of less than 50 and less than 60 cm/sec yielded sensitivities and specificities of 46% and 93%, and 57% and 89%, respectively, for the detection of portosystemic gradients exceeding 15 mm Hg. Use of a threshold midshunt velocity of less than 60 cm/sec or main portal vein velocity of less than 40 cm/sec raised the shunt dysfunction detection sensitivity to 86%, with a specificity of 54%. CONCLUSION: Doppler US is an effective noninvasive screening tool for detecting elevated portosystemic gradients and evaluating the functional status of a TIPS. Midshunt velocities of less than 60 cm/sec or main portal vein velocities less than 40 cm/sec are a useful threshold for detecting shunt dysfunction.

First-trimester US parameters of failed pregnancy.

PURPOSE: To test the reliability of established ultrasound (US) parameters in predicting the outcome of first-trimester pregnancy. MATERIALS AND METHODS: The authors retrospectively reviewed 2,655 first-trimester US scans in 2,285 patients. Parameters tested against outcome were (a) a yolk sac and mean gestational sac diameter of 8 mm on transvaginal US scans, (b) an embryo and mean sac diameter of 16 mm on transvaginal US scans, and (c) a difference between the mean sac diameter and crown-rump length of less than 5 mm (oligohydramnios) at 5.5-9.0 weeks gestation. RESULTS: Thirty (22%) of 135 patients without yolk sacs and with an 8-mm mean sac diameter developed live embryos: 24 had normal follow-up or delivery; six were lost to follow-up. Five (8%) of 59 patients with no depiction of embryos and with a 16-mm mean sac diameter developed live embryos: Two delivered, one spontaneously aborted, one had death of one twin embryo before being lost to follow-up, and one was lost to follow-up. Seventeen (0.74%) of 2,285 patients had early oligohydramnios: Six (35%) had normal follow-up scans or delivery, two (12%) spontaneously aborted, and nine (53%) were lost to follow-up. CONCLUSION: Established parameters predictive of early pregnancy failure potentially result in misdiagnosis of nonviability or poor prognosis when applied to a large, unselected patient population. Close follow-up is necessary in cases with borderline abnormal findings.

Post-cesarean section pain secondary to intussuscepting colonic adenocarcinoma.

The differential diagnosis for lower abdominal and pelvic pain following Cesarean section includes many causes, such as endometritis, abscess, pelvic hematoma, wound complications, pelvic vein thrombophlebitis, gastrointestinal dysfunction and obstruction. Colonic obstruction secondary to intussusception is a rare cause. We present a case of post-Cesarean section pain in a 26-year-old patient due to obstructing colonic intussusception secondary to colonic adenocarcinoma. Review of the literature failed to identify a previous case report of colonic adenocarcinoma with intussusception presenting early in the postpartum period. The diagnosis was initially made by ultrasound, and later corroborated by computed tomography, barium enema and laparotomy.

Strategy for repeat biopsy of patients with prostatic intraepithelial neoplasia detected by prostate needle biopsy.

PURPOSE: We evaluated the strategy for repeat biopsy of patients with prostatic intraepithelial neoplasia without concurrent carcinoma detected on prostate needle biopsy. MATERIALS AND METHODS: Of 1,275 consecutive patients undergoing prostate needle biopsy 61 were identified with prostatic intraepithelial neoplasia but without concurrent prostate carcinoma. Of the 61 patients 53 had undergone repeat biopsy. The medical records, transrectal ultrasound, and operative and pathological reports of these patients were reviewed. RESULTS: Repeat biopsy was done in 53 patients with prostatic intraepithelial neoplasia, yielding carcinoma in 15, prostatic intraepithelial neoplasia without carcinoma in 8 and benign tissue in 30. The yield of carcinoma from repeat biopsy of a prostatic intraepithelial neoplasia site was 8.3% (7 of 84 sites). A total of 18 sites of carcinoma was detected by repeat biopsy of a previous random biopsy site (8), a prostatic intraepithelial neoplasia site only (5), a transrectal ultrasound nodule (3), a palpable nodule and prostatic intraepithelial neoplasia site (1), and a transrectal ultrasound nodule and prostatic intraepithelial neoplasia site (1). Carcinoma was as frequently detected by repeat biopsy of a prostatic intraepithelial neoplasia site (6 patients) as by random repeat biopsy (6 patients). CONCLUSIONS: Repeat prostate needle biopsy of patients with prostatic intraepithelial neoplasia should include random repeat biopsy and repeat biopsy of transrectal ultrasound abnormalities as well as previous sites of prostatic intraepithelial neoplasia.

Ultrasound of focal hepatic lesions.

Hepatic sonography is useful in characterizing many focal liver lesions (Tables 2-6). It is safe, portable, and relatively inexpensive. With the development of color Doppler imaging, power Doppler imaging, and intravenous-ultrasound contrast agents, the ability to detect and precisely diagnose a focal hepatic lesion may be improved.

Body stalk deformity in a twin pregnancy: case report and review.

Body stalk deformity is a variety of the limb-body wall complex (LBMC)--the rare, complicated, congenital process believed to result from early rupture of the amnion and vascular disruption. Here we report a case of this anomaly in a twin pregnancy and describe the prenatal ultrasound findings.