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W D Middleton

Publications and source records attributed to W D Middleton.

At least 37 records · Page 2Linked to original sources
PubMed1996

Bowel wall thickening: differentiation of inflammation from ischemia with color Doppler and duplex US.

PURPOSE: To determine whether ultrasonography (US) can be used to differentiate inflammatory from ischemic bowel wall thickening. MATERIALS AND METHODS: Thirty-five patients (aged 23-96 years) with inflammatory or ischemic bowel wall thickening underwent US. Thickness was recorded, echotexture categorized, color Doppler flow graded, presence of intramural arterial signal recorded, and resistive index calculated. RESULTS: The difference between inflammatory and ischemic bowel wall thicknesses was not significant (P = .49). Differences in color Doppler flow (P < .0001), arterial signal (P = .0005), and bowel wall echotexture (P < or = .0200) between patients with inflammatory and ischemic bowel wall thickening were significant. Absence of or barely visible color Doppler flow and absence of arterial signal suggested ischemia; readily visible color Doppler flow and a stratified echotexture suggested inflammation. A resistive index less than 0.60 indicated inflammation. The difference in resistive index between the two groups was not significant (P = .12). CONCLUSION: Duplex and color Doppler flow US are helpful in differentiation between ischemic and inflammatory bowel wall thickening.

Case-Control Studies↗
PubMed1996

Angiomyolipoma and renal cell carcinoma: US differentiation.

PURPOSE: To analyze whether shadowing and other ultrasound (US) features were helpful for distinguishing angiomyolipoma (AML) from renal cell carcinoma (RCC). MATERIALS AND METHODS: US images were reviewed of 49 patients with RCC and 35 patients with AML. Each tumor was evaluated for size, location, echogenicity, homogeneity, shadowing, hypoechoic rim, and intratumoral cysts. When available, computed tomographic (CT) scans of AMLs were analyzed for the amount of fat and soft tissue in each lesion. RESULTS: AMLs tended to be smaller and more frequently echogenic than RCCs, but statistically significant overlap occurred. Shadowing was seen in 12 (33%) AMLs but was not seen in RCCs. Hypoechoic rims and intratumoral cysts were seen only in RCCs (numbers were too small to perform further statistical analysis). CONCLUSION: In hyperechoic renal masses, the presence of shadowing, a hypoechoic rim, and intratumoral cysts are important findings that may help distinguish AML from RCC.

Adult↗
PubMed1996

Local staging of endometrial carcinoma: comparison of transvaginal and intraoperative sonography and gross visual inspection.

OBJECTIVE: The purposes of this study were to compare transvaginal sonography (TVS), intraoperative sonography (IOS), and gross visual inspection of the uterus with the histopathologic findings in patients with endometrioid adenocarcinoma, and to compare the accuracies of TVS, IOS, and gross visual inspection in staging of the tumor. SUBJECTS AND METHODS: Sixteen patients with endometriod carcinoma were prospectively evaluated with TVS and IOS. Intraoperative gross visual inspection was also performed. Gray-scale, duplex, and color Doppler findings were used to stage patients. The location and depth of myometrial invasion and the presence of cervical involvement were recorded. At gross visual inspection, only the absence or presence and the depth of myometrial invasion (< or = 50% or >50%) were recorded. The data were analyzed three ways. First, in uterine specimens with myometrial invasion, a site-by-site comparison was made among the TVS and IOS findings and the final histologic results regarding location and depth of tumor invasion. Next, to determine tumor stage, myometrial invasion was defined in two ways: (1) absent, 50% or less, or greater than 50%; and (2) 50% or less or greater than 50%. Then imaging findings, gross visual inspection, and the final histologic results were compared. RESULTS: Of the 16 uterine specimens, eight had myometrial invasion, with 13 separate sites of tumor invasion. IOS correctly identified the location and depth (+/- 10% of the histologic depth) of tumor invasion at four (31%) sites, and TVS at one (8%) site. TVS and IOS overestimated myometrial invasion due to adenomyosis, bulky intraluminal tumor, and lymphovascular invasion. When myometrial invasion was defined as absent, 50% or less, or greater than 50%, TVS was correct in 60% of cases, IOS in 56%, and gross visual inspection in 53%. When myometrial invasion was defined as 50% or less or greater than 50%, TVS was correct in 93% of cases, IOS in 81%, and gross visual inspection in 80%. CONCLUSION: TVS and IOS are inaccurate in predicting the precise location and depth of myometrial tumor invasion. However, when a less rigorous definition of invasion is used, the accuracies of TVS and IOS are comparable to gross visual inspection in staging of the tumor.

Adult↗
PubMed1996

Peripheral portal venous blood flow alterations induced by hepatic masses: evaluation with color and pulsed Doppler sonography.

We examined 29 patients with intra- and extrahepatic masses and 10 normal volunteers with duplex and color Doppler ultrasonography. Portal blood flow adjacent to the masses was categorized as anterograde, retrograde, or nondetectable and was correlated with lesion size, character, and location. Anterograde flow was documented in the main portal vein and in the central right and left portal veins in all patients and volunteers. Flow in the peripheral portal veins near the lesion examined was retrograde in 17, anterograde in 10, and nondetectable in two of the patients. Retrograde peripheral flow was seen only in solid lesions, abscesses, and large subcapsular hematomas. Peripheral portal flow was anterograde in all of the volunteers. This study confirms that color Doppler sonography can detect alterations in portal flow induced by intra- and extrahepatic masses. The relatively common presence of peripheral portal flow reversal in patients with metastases and hepatocellular carcinomas indicates that it is not a reliable sign for differentiation between these entities.

Adult↗
PubMed1995

Diagnosis of venoocclusive disease of the liver after bone marrow transplantation: value of duplex sonography.

OBJECTIVE: The purpose of this study was to determine if duplex sonography of the hepatic vasculature can be used to detect venoocclusive disease in patients who have had bone marrow transplantation. SUBJECTS AND METHODS: Twenty-seven bone marrow transplant recipients were serially studied with hepatic duplex sonography before (n = 27) and biweekly after (n = 136) transplantation. Duplex waveforms were obtained from the hepatic artery and the portal and hepatic venous systems. Clinical records were reviewed to confirm the clinical diagnosis of venoocclusive disease (n = 5), including its time of onset and duration. Patients with venoocclusive disease were further split into two groups: those with clinically active disease and those with clinically inactive disease. The resistive index in the hepatic artery, the velocity in the portal vein, and the differences among bone marrow transplant values before and after transplantation were compared among the groups. RESULTS: On the basis of data obtained before transplantation, a resistive index greater than 0.76 and a change in resistive index greater than 0.10 after transplantation were considered abnormal. Similarly, velocity in the portal vein after transplantation was considered abnormal when the value was less than 4.3 cm/sec or more than 50.3 cm/sec. There was no statistically significant difference in the resistive index in the hepatic artery or velocity in the portal vein among patient groups. Hepatopetal portal venous flow was shown in 26 of 27 patients during the study. Portal venous flow was reversed in one patient with venoocclusive disease. Appropriately directed hepatic venous flow was demonstrated in all 27 patients. CONCLUSION: Our study shows that resistive index in the hepatic artery, velocity and flow direction in the portal vein, and flow direction in the hepatic vein as detected by duplex sonography are of no value in the diagnosis of venoocclusive disease after transplantation.

Adult↗
PubMed1995

Imaging of the common bile duct during laparoscopic cholecystectomy: sonography versus videofluoroscopic cholangiography.

OBJECTIVE: The purpose of this prospective study was to compare the accuracies of laparoscopic sonography and laparoscopic videofluoroscopic cholangiography in detecting common bile duct stones and in identifying ductal anomalies during laparoscopic cholecystectomy. SUBJECTS AND METHODS: Ninety-five patients who underwent laparoscopic videofluoroscopic cholecystectomy were prospectively studied with laparoscopic sonography and laparoscopic videofluoroscopic cholangiography. The number of successful studies, the time required to complete the study, and complications resulting from the study were recorded. The biliary system was evaluated for complete visualization of the common bile duct, visualization of the cystic duct, ductal anomalies, maximum diameter of the common bile duct, and common bile duct stones and/or debris. Also determined was whether laparoscopic sonographic findings altered operative management. RESULTS: Laparoscopic sonography was successfully performed in 93 of 95 patients, and laparoscopic videofluoroscopic cholangiography was successfully performed in 90 of 95 patients. The time required to complete laparoscopic sonography ranged from 3 to 18 min (mean +/- SD, 8 +/- 3 min), and that required to complete laparoscopic cholangiography ranged from 5 to 28 min (mean +/- SD, 14 +/- 6 min). Laparoscopic sonography visualized the complete common bile duct in 84 of 93 patients, and laparoscopic cholangiography did so in 86 of 90 patients. Laparoscopic sonography showed the cystic duct in 87 of 93 patients, and laparoscopic cholangiography did so in 80 of 90 patients. Laparoscopic sonography showed no ductal anomalies in any of the 93 patients. Laparoscopic cholangiography showed ductal variants in 13 of 90 patients; however, 11 of the variants were proximal to the sonographic scan plane. Laparoscopic sonography showed common bile duct stones in 12 of 93 patients, and laparoscopic cholangiography did so in five of 90 patients. Laparoscopic sonography altered operative management in two of 93 patients. CONCLUSION: Our results show that laparoscopic sonography is as accurate as laparoscopic videofluoroscopic cholangiography in visualizing the common bile duct and cystic duct and in detecting common bile duct stones. However, the data are too limited to determine whether laparoscopic sonography is as accurate as laparoscopic cholangiography in detecting ductal anomalies.

Adult↗
PubMed1994

Testicular microlithiasis: imaging appearances and pathologic correlation.

PURPOSE: To determine the spectrum of sonographic findings, clinical implications, and pathologic correlation in patients with testicular microlithiasis (TM). MATERIALS AND METHODS: The cases of 42 patients with the characteristic appearance of TM on sonograms were retrospectively evaluated for the number, pattern, and distribution of echogenic foci and for associated intratesticular abnormalities. Medical records and pathologic reports were reviewed. RESULTS: Considerable variation was found in the number and distribution of occurrences of TM (five to 60 echogenic foci per transducer field). In some patients, peripheral clustering was seen. Most patients demonstrated side-to-side symmetry, but asymmetric distribution was seen in eight patients and unilateral foci were seen in one patient. In 17 patients, a germ cell neoplasm was seen. One additional patient had a focal lesion that was proved to be an infarct. CONCLUSION: TM has a characteristic sonographic appearance. Because of the 40% occurrence of primary testicular neoplasm in association with it, TM cannot continue to be considered a benign finding.

Adolescent↗
PubMed1994

Ultrasonography of rotator cuff pathology.

Shoulder sonography is a valuable means of evaluating the rotator cuff and biceps tendon. In experienced hands, it is as sensitive as arthrography and magnetic resonance imaging for detecting rotator cuff tears and abnormalities of the biceps tendon. Because sonography is rapid, noninvasive, relatively inexpensive, and capable of performing bilateral examinations in one sitting, it should be used as the initial imaging test when the primary question is one of rotator cuff or biceps tendon abnormalities.

Diagnosis, Differential↗
PubMed1993

Hyperechoic renal cell carcinomas: increase in detection at US.

Recent reports have indicated that hyperechoic renal cell carcinomas (RCCAs) are more frequent among small cancers and that small cancers are being detected more frequently. To determine whether these trends have resulted in a change in the frequency of detection of hyperechoic RCCA and, in particular, in the frequency of RCCA mimicking angiomyolipomas (AMLs), the sonographic features of 90 pathologically proved RCCAs in 82 patients were retrospectively reviewed and correlated with tumor size. Tumor echogenicity was compared with that of normal renal parenchyma and classified as hypoechoic, isoechoic, slightly hyperechoic, or markedly hyperechoic. Thirty-one tumors were 3 cm in diameter or less, and 59 were larger than 3 cm. Ten (32%) of the tumors 3 cm in diameter or less were markedly hyperechoic and mimicked AMLs, whereas only one (2%) of the tumors larger than 3 cm had this appearance (P < .001). Eleven of the 90 tumors (12%) were markedly hyperechoic. Twenty-four (77%) of the small tumors were either slightly or markedly hyperechoic, compared with 19 (32%) of the larger tumors (P < .001). Because of the increased detection of small RCCAs in recent years, the number of hyperechoic cancers and the number of cancers mimicking AMLs have increased.

Adult↗
PubMed1993

Analysis of intratesticular arterial anatomy with emphasis on transmediastinal arteries.

PURPOSE: The vascular anatomic features of the testis were studied with color Doppler ultrasound to determine the prevalence and anatomic relationships of transmediastinal arteries. MATERIALS AND METHODS: Fifty testes in 26 men were prospectively examined to identify and analyze transmediastinal arteries by means of color Doppler equipment optimized for detection of slow blood flow. RESULTS: Transmediastinal arteries were present in 26 testes (52%). In the 24 men in whom both testes were evaluated, transmediastinal arteries were unilateral in 12 men (50%), bilateral in six men (25%), and absent in six men (25%). In four testes, transmediastinal arteries were multiple; in the rest, they were single. In most testes, they occurred in the superior half of the testis. Only three transmediastinal arteries (6%) branched within the testicular parenchyma. Seventeen transmediastinal veins were seen in 13 testes (26%). Ten of these 17 veins (59%) were paired with transmediastinal arteries; the seven others (41%) were isolated. CONCLUSION: Transmediastinal arteries occur in approximately one-half of normal testes and should be considered normal.

Adult↗
PubMed1993

Morphologic and hemodynamic findings at sonography before and after creation of a transjugular intrahepatic portosystemic shunt.

OBJECTIVE: The purpose of this study was to describe the morphologic and hemodynamic findings in the hepatic vasculature before and immediately after creation of a transjugular intrahepatic portosystemic shunt. SUBJECTS AND METHODS: We used gray-scale, duplex, and color Doppler sonography to prospectively examine 25 patients before and after percutaneous placement of a stent to create a transjugular intrahepatic portosystemic shunt. Patency and direction of flow were determined in the stent and in the main, right, and left portal veins. Flow velocity was measured in the stent and in the main portal vein. RESULTS: In all patients, the stent was easily identified as connecting branches of the portal and hepatic veins. Three thrombosed stents were correctly detected sonographically. One stent that was thought to be thrombosed at sonography was found to be patent at angiography. Flow velocities in the patent stents ranged from 73 to 185 cm/sec (mean, 130 +/- 33 cm/sec). Mean peak velocities in the main portal vein were 20 cm/sec before stent placement and 38 cm/sec after stent placement (p < .002). In 14 patients, flow direction in the left or right portal vein was hepatofugal after the stent was placed. In two of these 14 patients, long-term follow-up showed subsequent conversion of flow in the portal vein branches from hepatofugal to hepatopetal. One of these two patients had a thrombosed stent and the other had a hepatic vein stenosis above the stent. The second patient also had a proven decrease in flow velocity in the stent at the time of stenosis. CONCLUSION: We conclude that high flow velocities are expected in the main portal vein and in the stent immediately after the shunt is created and that flow in portal vein branches is usually hepatofugal. We recommend sonography soon after the shunt is created, so that baseline flow velocity in the stent and flow direction in portal vein branches can be established, because a subsequent decrease in flow velocity in the stent or a change in direction of flow in a portal branch may indicate stent malfunction.

Blood Flow Velocity↗
PubMed1992

Preliminary experience using endoscopic ultrasonography in the diagnosis of choledocholithiasis.

Twenty patients with symptomatic cholelithiasis and suspected choledocholithiasis were evaluated in an ongoing prospective trial using endoscopic ultrasonography (EUS), standard abdominal ultrasonography (US) and ERCP for the detection of choledocholithiasis prior to laparoscopic cholecystectomy. EUS was used successfully to image the extrahepatic bile duct in all patients. EUS detected three of four proven bile duct stones and correctly identified 16 bile ducts as stone free, thus being more accurate than standard abdominal US. The preliminary results of this ongoing prospective trial and the experience reported by other authors suggest that EUS may be as sensitive as ERCP in the detection of choledocholithiasis.

Cholangiopancreatography, Endoscopic Retrograde↗
PubMed1992

Testicular tumors: findings with color Doppler US.

A study of 28 patients with surgically proved testicular tumors was performed to determine the appearance at color Doppler ultrasound (US) scanning. There was a general correlation of tumor size and vascularity. Twenty of 21 (95%) tumors larger than 1.6 cm were hypervascular. Six of seven (86%) tumors smaller than 1.6 cm were hypovascular. One small, 1.1-cm-diameter seminoma was hypervascular, and one 2.8-cm-diameter seminoma was hypovascular. The histologic findings of the tumor did not correlate with the vascularity of the lesion as seen at color Doppler US. Resistive indexes ranged from .476 to 1.0 (mean, 0.70). Peak systolic velocities ranged from 8.4 cm/sec to 64.9 cm/sec (mean, 9.8 cm/sec). Venous flow was detected in eight tumors. The gray-scale findings, as well as history and physical examination findings, correctly suggested a neoplasm in all cases. The findings at color Doppler US were prospectively interpreted as indicative of neoplasm in 27 cases and as indicative of inflammation in one case. The authors conclude that color Doppler US scanning has only a limited role in the evaluation of testicular tumors.

Adolescent↗