Biomedical subjects
Publications and source records attributed to F B Murphy.
Advances in cross-sectional imaging, as well as cytologic and histologic techniques, have led to an expansion of the radiologist's role in the diagnosis and treatment of various liver diseases. This article reviews the indications, contraindications, techniques, and results of hepatic biopsies and fluid drainage procedures performed with the aid of cross-sectional imaging.
The results of computed tomographic (CT)-guided percutaneous drainage in eight patients with tubo-ovarian abscesses are reported. Seven patients (88%) recovered without surgery and required no further treatment. One patient had marked clinical improvement but still required a posterior colpotomy. No complications occurred. One patient had a recurrence of symptoms 20 months after the procedure that represented a new infection. The role of CT-guided percutaneous drainage in tubo-ovarian abscesses as well as an analysis of the technical aspects associated with a successful procedure are discussed.
Pneumothorax is the most common complication after CT-guided pulmonary interventional procedures and should be promptly diagnosed and treated. Because it is easier to obtain CT scans than chest radiographs after CT-guided interventional procedures, it is important to know the sensitivity of CT in detecting pneumothoraces. To determine the sensitivity of CT for detecting procedure-induced pneumothoraces, we retrospectively reviewed 70 pulmonary interventional procedures performed under CT guidance. The sensitivity for detecting pneumothoraces with CT was compared with the detection rate with expiratory chest radiographs. Thirty-two (46%) of 70 procedures resulted in pneumothorax. Twenty-nine (91%) of the pneumothoraces were detected on CT scans and 27 (84%) were detected on chest radiographs. The difference between these two detection rates was not statistically significant (p less than .90). We conclude that postprocedure CT scans can replace expiratory chest radiographs for the detection of pneumothoraces after CT-directed pulmonary procedures.
One hundred and two patients with cirrhosis and portal hypertension were evaluated sonographically to determine the presence or absence of cholelithiasis. The gallbladder was visualized in 80 of 102 patients. Cholelithiasis was present in 43 of 80 cases (54%). All 22 patients in whom the gallbladder was not seen sonographically had had a previous cholecystectomy. Five of them were operated on prior to development of cirrhosis with portal hypertension, but 14 of the remaining 17 (82%) had evidence of cholelithiasis at pathology. Hence, there was an overall incidence of cholelithiasis of 59% among out 97 patients. This study as well as previous autopsy data indicate an increased incidence of cholelithiasis in patients with cirrhosis, irrespective of etiology or sex. The incidence of cholelithiasis in this study, however, was approximately twice that previously reported in cirrhotics at autopsy. Furthermore, patients with portosystemic shunts showed a significantly higher incidence of cholelithiasis compared to patients who were not shunted (68% vs 49%, p = 0.028). We believe the severity and duration of cirrhosis in our patient population, all with documented portal hypertension, may be the cause of this increased incidence.
The presence of ascites has been considered a contraindication to percutaneous biopsy of the liver. To determine the validity of this assumption, we performed percutaneous biopsies of the liver under CT or sonographic guidance in 28 patients who had ascites and in 28 patients who did not have ascites and compared the complication rates in the two groups. Twenty-two patients (79%) in the group with ascites and 19 patients (68%) in the group without ascites had biopsies to determine the cause or extent of chronic liver disease. The remainder were oncologic patients who had biopsies to determine the cause of a focal hepatic mass. The complication rate in the patients who had ascites (32%) was less than that in the patients who did not have ascites (43%) (the difference did not reach statistical significance, p less than .30). In the ascites group, complications included transient hypotension (five patients), a mild-to-moderate fall in hematocrit (three patients), and a small leak of ascites from the biopsy site (one patient). In the control group, minor complications included transient hypotension (three patients), a mild-to-moderate fall in hematocrit (seven patients), and a small subcapsular hematoma (one patient). One major complication occurred in the control group: a patient required a blood transfusion because of the fall in his hematocrit. We conclude that the complication rate in liver biopsies guided by CT or sonography in the presence of ascites is not higher than similar biopsies done in the absence of ascites. Ascites should not be considered a contraindication for performing such biopsies.
A prospective study compared the efficacy of Doppler ultrasonography (US) and magnetic resonance (MR) imaging in evaluating 38 renal allografts, with specific attention to transplant rejection. Forty-three Doppler US and 42 MR examinations were performed and interpreted. Histologic correlation was obtained from 22 biopsy or nephrectomy specimens. Clinical correlation or a response to instituted therapy was used as confirmation in the remaining allografts. Accuracy in identifying cyclosporine toxicity or acute tubular necrosis could not be evaluated because there were few such cases, with concomitant rejection in most. The ability to predict and identify presence or absence of rejection was not affected by different serum creatinine values. Doppler US was significantly superior to MR imaging in identifying allograft rejection, demonstrating a higher sensitivity (95% vs. 70%), specificity (95% vs. 73%), and accuracy (95% vs. 71%). Because of its low cost and accessibility, Doppler US should become the primary modality for renal transplant screening.
Pulsed Doppler sonography and liver panangiography were performed in 43 patients with cirrhosis. Fourteen patients were evaluated preoperatively, and 28 patients were evaluated after a variceal decompressive shunt. One patient was studied before and after undergoing a shunt. The direction of portal blood flow by Doppler sonography was compared with both the grading pattern and direction of flow by angiography. When portal blood flow was determined to be antegrade by Doppler sonography, angiography showed antegrade flow in 84% (grade I, II, or III portal venous pattern). Six percent had retrograde flow (grade IV), and 10% had portal vein thrombosis. When the portal blood flow was determined to be retrograde by Doppler sonography, angiography showed retrograde flow (grade IV portal venous pattern) in 80% and antegrade flow (grade I, II, or III) in 20%. When an inadequate Doppler tracing was obtained from the portal vein, angiography showed either grade I, II, or III in 38%; grade IV in 50%, and portal vein thrombosis in 13%. There was poor correlation between the calculated mean flow rates, as determined by Doppler sonography, and the angiographic grade. We conclude that pulsed Doppler sonography is accurate in determining the direction of portal flow when an adequate tracing is obtained (36 of 44 studies). When an inadequate tracing is obtained, retrograde portal flow or portal vein thrombosis is likely.
Ascites, hepatomegaly, and abdominal pain constitute the classic triad of the Budd-Chiari syndrome of hepatic-vein or inferior-vena-cava obstruction. This condition was first mentioned by Budd in the mid 1800s and additional information was provided by Chiari in the 1890s. In nearly two-thirds of patients the exact etiology cannot be determined. The syndrome has, however, been associated with hypercoagulable states, neoplasms, trauma, medications, and congenital abnormalities. The diagnosis is difficult to make clinically; therefore, radiology plays a critical role in the workup of these patients. Nuclear medicine, sonography, CT, angiography, and MRI all provide valuable diagnostic information. These data combined with hepatic biopsy determine which patients should be treated by percutaneous angioplasty or surgery, and also determine the type of shunt to be performed (such as the mesoatrial shunt when the inferior vena cava is occluded or severely compressed). Noninvasive imaging is also useful in the follow-up of patients after both percutaneous angioplasty and surgery.
With a recently described rat model technique for direct hepatic injection of tumor cells for imaging research, there were concerns that the injection itself might produce lesions detectable with magnetic resonance (MR) imaging, thereby producing false-positive results. To examine this possibility, the authors prospectively studied 14 Sprague-Dawley rats after direct hepatic injection of cells from a rat hepatoma cell line. The rats were imaged with a variety of pulse sequences before and after intravenous injection of the contrast agent manganese dipyridoxal diphosphate at a dose of 8 mumol/kg. No intrahepatic lesions could be detected with MR imaging during the first 6 days after direct hepatic injection of the tumor cells. Therefore, the direct injection technique should be accurate for evaluating various MR imaging sequences and contrast agents for early hepatic tumor detection.
Due to the development and refinement of computed tomography (CT), sonography, and interventional techniques, the field of interventional radiology has seen tremendous growth in recent years. In particular, the precise anatomic detail provided by CT and sonography has allowed percutaneous biopsies and abscess drainages to be performed safely and effectively. Percutaneous biopsies are now becoming the most common interventional radiographic procedures in many institutions. The usual indications for a biopsy are to determine the etiology of a mass, neoplasm, or inflammation, and to determine whether masses in known oncologic patients represent scarring or residual viable tumor. Accuracy rates for most percutaneous CT-directed biopsies are well over 90%, and the complication rate is very low. CT-directed percutaneous abscess drainages are also safe and effective and, in most cases, will be preferable to surgical drainage. The initial indications for percutaneous drainage (single, unilocular fluid collections) have been greatly expanded to include multiloculated collections, interloop abscesses, periappendiceal abscesses, and even percutaneous cholecystotomies. Biopsy and drainage procedures, together with their accuracy rates, indications and complications, are reviewed in this monograph.
Involvement of the liver in hemochromatosis is generally a diffuse process. A review of the recent radiologic literature showed no reports of focal involvement of the liver by hemochromatosis. We report a case of focal hepatic lesions seen on magnetic resonance images which, when biopsied, proved to be an area of focal hemochromatosis.