Comparison of unenhanced, hepatic arterial-dominant, and portal venous-dominant phase helical CT for the detection of liver metastases in women with breast carcinoma.

OBJECTIVE: The purpose of this study was to evaluate triple-phase helical CT for detection of hepatic metastases from breast carcinoma. SUBJECTS AND METHODS: Breast cancer patients were studied prospectively with triple-phase helical CT in 300 consecutive examinations. Hepatic arterial-dominant and portal venous-dominant phase scans were initiated at 20 and 65 sec, respectively, after IV injection of 175 ml of iopamidol (30 mg/ml) at 5 ml/sec. Three independent observers each reviewed 200 cases of the portal venous-dominant phase for lesion number, conspicuity, and attenuation. Subsequently, portal venous-dominant phase images were reevaluated in conjunction with hepatic arterial-dominant phase or unenhanced images. RESULTS: Hepatic metastases were identified in 79 (26%) of 300 cases. Lesions detected on portal venous-dominant, hepatic arterial-dominant, and unenhanced images were as follows: observer 1, n = 198, 164, and 171; observer 2, n = 254, 233, and 233; and observer 3, n = 291, 270, and 276 (p > .05). The mean total lesion count was 387, with more lesions detected on portal venous-dominant phase than on either hepatic arterial-dominant phase or unenhanced images (p < .001 and p < .0001, respectively). For individual observers, 10-26% of lesions were hypervascular on hepatic arterial-dominant phase images. Two to 4% of lesions were identified only on hepatic arterial-dominant phase or unenhanced images. However, in these few cases, the lesions either were false-positives or were seen in conjunction with additional metastases on portal venous-dominant images. CONCLUSION: Routine use of triple-phase CT in patients with breast carcinoma may not be warranted: Addition of the hepatic arterial-dominant phase or unenhanced images revealed few additional lesions in our group of 300 patients.

The oblique pharyngogram: value in the assessment of dysphagia.

BACKGROUND: To evaluate the diagnostic value of oblique views of the pharynx in patients with dysphagia. METHODS: One hundred thirty-three patients with symptoms referable to the cervical region underwent pharyngoesophography that included views of the pharyngoesophageal junction filmed at three frames per second and spot films of the pharynx obtained in distended frontal, lateral, and both oblique projections. Examination was completed with assessment of the entire esophagus and gastric cardia. RESULTS: The oblique views identified abnormalities not shown on the standard views in 5% of patients. The oblique views proved useful in 12%, where the lower pharynx was obscured in the lateral projection by large shoulders, and in 18% to assess the valleculae when this region was obscured by the occiput and mandible in the frontal projection. In 12%, the oblique views proved useful in demonstrating normal structures when artifacts raised the possibility of lesions on the standard projections. In 10%, poor technique impaired visualization of pharyngeal structures on the standard projections, but repeat swallows in the oblique projections proved adequate to assess these regions. Three (27%) of the 11 cases of cervical esophageal webs were best seen on oblique views, and in another three patients the webs were visible only on oblique views. CONCLUSIONS: Oblique views are of value in the assessment of the pharynx. There will be instances when the standard projections are inadequate, and these alternative views will complement the evaluation of this region. The addition of oblique views will sometimes improve the confidence of the interpretation of normality or assist evaluation of the extent of an abnormality.

Interobserver variability in the interpretation of unenhanced helical CT for the diagnosis of ureteral stone disease.

PURPOSE: The purpose of this study was to analyze interobserver agreement in the interpretation of unenhanced helical CT (UHCT) for the evaluation of ureteral stone disease and obstruction. METHOD: One hundred three UHCT examinations were independently and retrospectively reviewed by five readers including attending radiologists, a radiology resident, and an attending urologist. Examinations were interpreted as positive, negative, or indeterminate for ureteral stone disease and obstruction. The Cohen kappa test was used to measure interobserver agreement. The accuracy of the readers was also assessed. RESULTS: The kappa value ranged from 0.67 to 0.71 among the three attending radiologists and from 0.65 to 0.67 among the radiology attending physicians and radiology resident. Although the urologist tended to agree less well with the other readers (kappa range: 0.33-0.46), there was no statistically significant difference (p < 0.05) in the accuracy among all five readers. The percentage of cases interpreted as indeterminate ranged from 8 to 25% and almost invariably involved difficulty distinguishing phleboliths from minimally obstructing distal ureteral calculi. The percentage of UHCT scans correctly interpreted as positive and correctly interpreted as negative ranged from 73% (n = 27) to 86% (n = 32) and 63% (n = 22) to 86% (n = 30), respectively. CONCLUSION: Interobserver agreement was very good among the radiology attending physicians and resident and moderate with the urologist. The examination is an accurate technique in the evaluation of ureteral stone disease, although limitations exist, particularly in the diagnosis of minimally obstructing distal ureteral calculi.

Carcinoid metastases to the liver: role of triple-phase helical CT.

PURPOSE: To evaluate triple-phase helical computed tomography (CT) of carcinoid liver metastases. MATERIALS AND METHODS: Triple-phase helical CT was performed in 31 patients with proved carcinoid liver metastases. Hepatic arterial-dominant phase (HAP) and portal venous-dominant phase (PVP) images were obtained 20 and 70 seconds after intravenous iopamidol injection. Four independent readers reviewed each phase for lesion number, conspicuity, and attenuation relative to liver. Three readers reviewed each phase to determine which phase best showed the lesions. RESULTS: The lesions detected by readers 1-4 were as follows: noncontrast phase, 164, 177, 204, and 229 lesions; HAP, 178, 177, 214, and 238 lesions; and PVP, 180, 189, 215, and 250 lesions (P > .05). On HAP images, readers found that 80, 73, 96, and 102 lesions were hyperattenuating. Consensus indicated there were 206 focal lesions. Of these 206 lesions, 72, 72, and 62 lesions were best seen on the noncontrast phase, HAP, and PVP images, respectively. Six, 28, and six lesions were seen only on the noncontrast phase, HAP, and PVP images, respectively. Two patients had lesions seen only on the HAP images. CONCLUSION: The HAP and, to a lesser extent, the noncontrast phase provide added value in evaluating carcinoid liver metastasis.

Pancreatic malignancy: effect of dual-phase helical CT in tumor detection and vascular opacification.

PURPOSE: To determine the relative value of hepatic arterial and portal venous phase helical computed tomographic (CT) scans for tumor detection and vascular opacification in patients with pancreatic malignancy. MATERIALS AND METHODS: Ninety-five patients who had or were suspected of having pancreatic disease underwent dual-phase helical CT. Arterial phase scans were acquired 20-40 seconds after contrast material administration; venous phase scans, 70-100 seconds after administration. Three readers independently scored images in a blinded fashion for the presence of tumor, for lesion attenuation relative to normal pancreas, and for vascular opacification. RESULTS: The final diagnosis was pancreatic malignancy (n = 60), acute or chronic pancreatitis (n = 22), and normal pancreas (n = 13). The readers identified possible or definite tumors on arterial phase studies in 47-50 patients and on venous phase studies in 48-53 patients (P > .10). There was no statistically significant difference in tumor attenuation between scans from the two phases (P > .05). Agreement between the readers for tumor detection was not affected by the scanning phase (P > .10). Opacification of arteries and of veins was greater on arterial phase scans and on venous phase scans, respectively (P < .001). CONCLUSION: The acquisition of arterial phase scans in addition to venous phase scans does not result in improved detection of pancreatic malignancies.

Abdomen after a Puestow procedure: postoperative CT appearance, complications, and potential pitfalls.

PURPOSE: To evaluate the postoperative computed tomographic (CT) appearance, complications, and potential pitfalls after a Puestow procedure (lateral side-to-side pancreaticojejunostomy). MATERIALS AND METHODS: Forty CT examinations were performed after the Puestow procedure in 20 patients. Images were retrospectively reviewed by three radiologists. RESULTS: The pancreaticojejunal anastomosis was identified at 30 examinations and was immediately anterior to the pancreatic body or tail. The anastomosis contained fluid or gas on 11 scans and oral contrast material on four scans. On 15 scans, the anastomosis appeared as collapsed bowel without gas, fluid, or oral contrast material. The Roux-en-Y loop was identified on 28 (70%) scans and contained fluid or gas on 16 scans and oral contrast material on six scans. The Roux-en-Y loop appeared as collapsed bowel on six scans. When the anastomosis or Roux-en-Y loop contained fluid and gas, the appearance mimicked that of a pancreatic or parapancreatic abscess. Peripancreatic stranding was present on 28 scans and was due to either ongoing pancreatitis or postoperative change. Complications included 15 transient fluid collections, three abscesses, four pseudocysts, one hematoma, and one small-bowel and Roux-en-Y obstruction. CONCLUSION: Knowledge of the anatomy after a Puestow procedure is essential for accurate interpretation of CT scans.

Sonographic assessment of lower limb vein diameters: implications for the diagnosis and characterization of deep venous thrombosis.

OBJECTIVE: The goals of this study were to define the normal range of diameters in the deep veins of the thigh and to compare this range with diameters of veins with acute thrombus and of veins with chronic changes from prior deep venous thrombosis (DVT). SUBJECTS AND METHODS: The anteroposterior diameter of the vein and adjacent artery was measured at five predefined levels in 975 legs of patients referred for sonographic examination for suspected DVT. The mean vein diameter and mean vein-to-artery ratio were calculated for normal veins, vein segments with acute DVT, and vein segments with chronic changes from prior DVT. RESULTS: The diameter of normal deep leg veins was largest at the level of the common femoral vein (mean diameter, 10.5 mm). The diameter progressively decreased until the mid superficial femoral vein and remained relatively constant (mean diameter, 6.4-6.8 mm) more caudally. Similarly, vein-to-artery ratios progressed from a mean ratio of 1.3 in the common femoral vein to 1.2 at other levels. We found no significant differences in vein diameter between the right and the left legs. Vein segments with acute thrombus were larger than corresponding segments of normal veins. However, we found considerable overlap in the ranges of diameter of veins with and without acute DVT. At corresponding levels, veins with chronic DVT tended to be narrower than normal veins; however, the differences were small, and this diameter range also substantially overlaps that of normal veins. CONCLUSION: When grouped, veins with acute DVT were larger than normal veins. Likewise, veins with chronic DVT were smaller than normal veins. Because we found that the ranges of diameters of veins overlapped for different groups of veins, size alone is unlikely to provide compelling evidence for the diagnosis of acute versus chronic DVT, except at extreme diameters. Diameters of veins as revealed by sonography should be interpreted in the context of other sonographic findings.

Doppler US measurement of portal venous flow: variability in healthy fasting volunteers.

PURPOSE: To describe the intrinsic sampling variability of measurements of portal venous flow in healthy volunteers and to estimate the variability attributable to the sonographer, the subject, and the measurement. MATERIALS AND METHODS: In a randomized controlled fashion, nine sonographers measured portal venous flow in five subjects. Each sonographer measured portal venous flow in each volunteer during three separate sessions with three measurements per session. Analysis of variance was used to estimate the contribution of several factors to the observed variability. RESULTS: Overall mean portal venous flow was 390 mL/min +/- 234 (range, 18-1,511 mL/min). The estimated variance components were 1.1 (3%), 2.5 (7%), 7.2 (21%), and 24.0 (69%) for the subject, the sonographer, the interaction between subject and sonographer, and the measurement or intrinsic variability. Similar results were obtained when the analysis of variance was fit by using the rank and median of the measurements. CONCLUSION: Substantial variability exists in measurement of portal venous flow. Variability attributed to inherent differences in repeat measurements contributes more to overall variability than that attributed to either sonographers or subjects.

Helical CT for detecting focal liver lesions in patients with breast carcinoma: comparison of noncontrast phase, hepatic arterial phase, and portal venous phase.

PURPOSE: Our goal was to compare noncontrast phase (NCP), hepatic arterial phase (HAP), and portal venous phase (PVP) helical CT for the detection of focal liver lesions in patients at risk for having metastases from breast carcinoma. METHOD: Eighty-four consecutive CT scans in 80 women with known or suspected liver metastases from breast carcinoma were prospectively evaluated with triple phase helical CT. After NCP, Isovue 300 was administered at 3 ml/s for 40 s, then 2 ml/s for 30 s, with scan delays of 25 s (HAP) and 76 s (PVP), slice thickness of 7 mm, and pitch of 1:1. Two reviewers evaluated each phase for focal liver lesions in a blinded and random fashion followed by side-by-side review for consensus. RESULTS: By consensus, 40 CT scans were normal and 44 CT scans had a total of 105 lesions (46 lesions were graded malignant). PVP detected 39 (85%), HAP 27 (59%), and NCP 28 (61%) malignant lesions. Two malignant lesions were seen only on HAP, 3 only on NCP, and 10 only on PVP. The remainder of lesions were seen on more than one phase. PVP was graded best for detecting lesions in 27 (61%), HAP best in 7 (16%), NCP best in 4 (9%), and PVP equivalent to HAP in 6 (14%) of the 44 cases with lesions. CONCLUSION: In our breast cancer patient population, PVP was superior to NCP and HAP for liver lesion detection. Because no CT scan was converted from negative to positive due to the addition of NCP or HAP, the routine use of these two phases cannot be justified when the clinical concern is the presence or absence of metastases.

Functional abnormalities of the esophagus: a prospective analysis of radiographic findings relative to age and symptoms.

OBJECTIVE: The prevalence and severity of functional abnormalities of the esophagus seen on fluoroscopic examination were compared with the age and symptoms of the patients. SUBJECTS AND METHODS: The esophagus was examined radiographically in 139 consecutive outpatients 19-84 years old. All patients completed a data sheet about their symptoms, and medical records were reviewed to determine the main indication for the examination. Videofluoroscopy was used to evaluate primary peristalsis, proximal escape, and tertiary activity in the esophagus. The severity of proximal escape and activity was classified. RESULTS: Patients were categorized into three age groups: 39 years old or younger (n = 33); from 40 to 60 years old (n = 55); and 61 years old or older (n = 51). Abnormal esophageal motility, defined as disruption of peristalsis on two or more of five swallows, was found in 24% of patients 39 years old or younger, 36% of patients from 40 to 60 years old, and in 49% of patients 61 years old or older (p > .05). However, evaluation of the number of disrupted peristaltic swallows by age revealed 18% abnormal swallows in patients 39 years old or older, 27% in patients from 40 to 60 years old, and 37% in patients 61 years old or older (p < .01). Proximal escape and tertiary contractions increased significantly with the age of the patient. Regardless of age, proximal escape was seen in 79% of swallows and tertiary contractions were seen in 48% of swallows with disrupted peristalsis. The prevalence and severity of proximal escape and tertiary contractions increased in the older patients. Symptoms had no correlation with status of esophageal motility (p > .05). In 22 patients with secondary diseases, including rheumatoid arthritis and diabetes mellitus, those diseases showed no correlation with the status of esophageal motility. CONCLUSION: The prevalence of functional abnormalities of the esophagus increased with age. Most patients with abnormal swallows showed proximal escape with or without tertiary activity. Patients' symptoms and other diseases did not correlate with the status of their esophageal motility.

Hepatic artery: variability in measurement of resistive index and systolic acceleration time in healthy volunteers.

PURPOSE: To determine the intrinsic sampling variability of measurements of hepatic artery resistive index and systolic acceleration time in healthy subjects and to estimate the components of variability attributable to the sonographer, individual measurement, and subject. MATERIALS AND METHODS: In a randomized, controlled (blinded) fashion, nine sonographers measured hepatic artery resistive index and systolic acceleration time in five healthy subjects by using Doppler ultrasound (US). Analysis of variance was used to estimate the contribution of several factors to the observed variability in measurements. RESULTS: The standard deviation for a single measurement was 0.08 for resistive index and 39 msec for systolic acceleration time. For resistive index, the estimated variance components were 0.0012 (18%), 0.0004 (6%), and 0.0050 (76%) for the subject, sonographer, and intrinsic variability, respectively. For systolic acceleration time, the estimated variance components were 59 msec (4%), 264 msec (17%), and 1,250 msec (79%) for the subject, sonographer, and intrinsic variability, respectively. CONCLUSION: Because of substantial variability in hepatic arterial measures, caution is indicated when interpreting small changes in the measurement of these Doppler US indexes.

Timing of parenchymal enhancement on dual-phase dynamic helical CT of the liver: how long does the hepatic arterial phase predominate?

OBJECTIVE: Dual-phase dynamic helical CT is now being used to detect and characterize benign and malignant hypervascular lesions in the liver. The purpose of this study is to define the timing and degree of parenchymal enhancement of normal liver during the hepatic arterial phase. SUBJECTS AND METHODS: This prospective study included 102 patients with known or suspected hypervascular hepatic lesions who underwent dual-phase helical CT. After unenhanced CT scanning, we injected iopamidol (Isovue 300; Bracco Diagnostics, Princeton, NJ) at 3 ml/sec for 120 ml, then at 2 ml/sec for 55-60 ml. Scan delay for the hepatic arterial phase was 25 sec and for the portal venous phase was 76 sec. Section thickness was 7 mm and pitch was 1:1. Operator-defined regions of interest were obtained from all three phases. RESULTS: Mean unenhanced attenuation of the liver was 51 +/- 12 H. The liver revealed progressive enhancement during the hepatic arterial phase as follows: an increase of 10 H occurred at a mean time of 33 +/- 4 sec, 20 H at 39 +/- 6 sec, 30 H at 44 +/- 8 sec, 40 H at 46 +/- 6 sec, and 50 H at 48 +/- 5 sec. At 20 H and 30 H of enhancement, we found a statistically significant difference (p < .01) for the mean times of men and women. Mean peak enhancement during the portal venous phase was 89 +/- 23 H. CONCLUSIONS: Because the hepatic arterial contribution to liver perfusion is approximately 30%, parenchymal enhancement greater than approximately 30% of peak might indicate portal venous predominance. In our study, this percentage corresponded to an increase of approximately 30 H. Therefore, detection of hypervascular lesions in the hepatic arterial phase may be compromised when imaging lasts longer than approximately 44 sec after the initiation of contrast material injection because 44 sec was the mean time for 30 H of enhancement in our series. However, variability between patients was marked, particularly between men and women. Furthermore, the data suggests that the hepatic arterial phase may be relatively brief and that it may be difficult to image properly using current helical CT technology.

Can the US examination for lower extremity deep venous thrombosis be abbreviated? A prospective study of 755 examinations.

PURPOSE: To determine if the ultrasound (US) survey of the lower extremity for deep venous thrombosis (DVT) can be curtailed without compromising diagnostic efficacy. MATERIALS AND METHODS: The authors performed 755 US examinations in 721 patients (1,024 lower extremities) referred for suspicion of lower extremity DVT. The full lengths of the deep veins were studied, and findings were categorized at five locations: common femoral vein (CFV), proximal superficial femoral vein (CFV), mid-SFV, distal SFV, and popliteal vein (PV). RESULTS: Acute thrombus was seen in one or more veins in 131 (17.4%) of the 755 examinations. DVT isolated to a single vein was seen in 28 (21.4%) of the 131 positive examinations: DVT was limited to the CFV in eight studies (61%), to the SFV in six studies (4.6%), and to the PV in 14 studies (10.7%). CONCLUSIONS: DVT limited to a single vein occurs with sufficient frequency that the US screening survey cannot be abbreviated without loss of diagnostic efficacy.

Functional abnormalities of the pharynx: a prospective analysis of radiographic abnormalities relative to age and symptoms.

PURPOSE: To determine the prevalence and severity of functional abnormalities of the pharynx relative to patient age and symptoms. MATERIALS AND METHODS: Radiographic evaluation of the pharynx was performed in 110 consecutive outpatients aged 19-84 years old who had no previous surgery of the larynx, pharynx, or esophagus. Each patient completed a symptom data sheet, and we reviewed medical records to determine the main indication for each examination. Videofluoroscopy and static filming in frontal and lateral positions were done with 20-ml barium boluses. We then evaluated functional abnormalities and classified abnormal findings by type and severity. RESULTS: We categorized patients by age into three groups: less than 40 years old (n=31), between 40 and 60 years old (n =42), and greater than 60 years old (n=37). We found a significant increase in the prevalence (23%, 36%, 57%, respectively) and severity of functional abnormalities of the pharynx in older patients (p < .05). Laryngeal penetration, aspiration, pharyngeal stasis, and cricopharyngeal bar were the main abnormalities found in the two older groups. However, we found no correlation between functional abnormalities of the pharynx and symptoms and indications (p > .05). CONCLUSION: Functional abnormalities of the pharynx increased in prevalence and severity with age. Often these findings were not related to specific pharyngeal symptoms and must be interpreted cautiously in older patients.

Videofluoroscopic evaluation of patients with Guillain-Barré syndrome.

We reviewed 14 patients with clinically confirmed Guillain-Barré syndrome for swallowing dysfunction. All had swallowing dysfunction varying from mild to severe. Six patients (43%) had equivalent impairment during oral and pharyngeal phases. Seven patients (50%) had more severe functional abnormalities during the pharyngeal phase than during the oral phase. One patient (7%) had moderate disorder during the oral phase and mild disorder during the pharyngeal phase. Thirty-six percent of the patients had moderate-to-severe dysfunction during the oral phase, and 71% had moderate-to-severe dysfunction during the pharyngeal phase. In 5 patients who had multiple sequential examinations, moderate or severe swallowing disorders improved to mild-to-moderate disorders within 4-8 weeks after the onset of the symptoms. Residual swallowing disorders may be seen in those who had severe swallowing dysfunction during the later phases of their disease. Further investigations are needed to determine if swallowing abnormalities persist after complete recovery from Guillain-Barré syndrome.

Barrett esophagus and adenocarcinoma.

Barrett esophagus has become a common lesion in the esophagus; it is presumably caused by reflux esophagitis. Double-contrast barium esophagraphy improves radiographic evaluation of Barrett esophagus. The presence of midesophageal stricture, mucosal reticular pattern, and deep esophageal ulceration suggests the presence of Barrett esophagus. Other findings, such as hiatal hernia, thickened mucosal folds, and gastroesophageal reflux, are also frequently seen in Barrett esophagus but are not specific. Adenocarcinoma may complicate Barrett mucosa, usually with severe dysplasia. Adenocarcinoma has morphologic forms similar to squamous cell carcinoma in the esophagus. Barium esophagram, CT scans, and endoscopic sonography are used to evaluate and stage adenocarcinoma in the esophagus.