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J T Ferrucci

Publications and source records attributed to J T Ferrucci.

At least 19 recordsLinked to original sources
PubMed1992

Accumulation of iron oxide particles around liver metastases during MR imaging.

The histologic nature of the bright ring ("peritumoral edema") around some liver metastases on T2-weighted magnetic resonance (MR) images is controversial. In the case reported, particles of the iron oxide contrast agent AMI-25 are retained in the peritumoral zone of a colon cancer metastasis, causing the bright ring to disappear. The location of iron particles in resected specimens could be used systematically to study peritumoral edema.

Adenocarcinoma↗
PubMed1992

Percutaneous obliteration of the cystic duct with a holmium:yttrium-aluminum-garnet laser: results of in vitro and animal experiments.

OBJECTIVE: The purpose of this study was to investigate the feasibility of using a holmium:yttrium-aluminum-garnet laser to permanently occlude the cystic duct in order to isolate the gallbladder from the biliary-enteric circulation and prevent gallstone formation. MATERIALS AND METHODS: To determine the optimal laser parameters (power and pulsing rate) for cystic duct thermocoagulation, 20 freshly excised porcine gallbladders with intact cystic ducts underwent low-energy (0.075-0.085 J/pulse) or high-energy (0.20-0.25 J/pulse) thermocoagulation. Histopathologic examination was done to determine the extent of cystic duct injury. After in vitro experiments, percutaneous transcholecystic laser thermocoagulation of the cystic duct was performed on 23 anesthetized domestic pigs (four controls). Cholangiograms immediately after laser thermocoagulation were obtained to assess cystic duct occlusion. Animals were sacrificed for histopathologic correlation immediately after laser thermocoagulation (n = 4), 72 hr later (n = 4), and 6 weeks later (n = 15). RESULTS: In the in vitro studies, all 10 cystic ducts in the high-energy group were occluded, while only four in the low-energy group were occluded. At histology, all cases in both groups showed circumferential injury to the cystic duct wall without injury to the cystic artery or vein. In the in vitro experiments, the cystic duct was successfully cannulated in 21 (91%) of 23 animals. Cholangiography after thermocoagulation showed occlusion of the cystic duct in 16 (84%) of 19 cases. Immediately after laser thermocoagulation, the cystic duct mucosa was circumferentially destroyed, whereas after 72 hr necrosis of the cystic duct wall and periductal tissues had occurred. By 6 weeks, all pigs had complete cystic duct fibrosis without injury to the common bile duct. CONCLUSION: Holmium:yttrium-aluminum-garnet laser thermocoagulation of the cystic duct can be performed easily, results in immediate cystic duct occlusion, and leads to permanent fibrous ductal obliteration by 6 weeks.

Animals↗
PubMed1992

Percutaneous chemical gallbladder sclerosis after laser-induced cystic duct obliteration: results in an experimental model.

OBJECTIVE: Chemical gallbladder sclerosis has been attempted as a way to defunctionalize the gallbladder in patients who have undergone nonsurgical removal of gallstones and who are unable to undergo surgical/laparoscopic cholecystectomy. The purpose of this investigation was threefold: to study an animal model for chemical sclerosis of the gallbladder with 95% ethanol and 3% sodium tetradecyl sulfate, to attempt chemical sclerosis immediately after percutaneous cystic duct obliteration by laser thermocoagulation, and to assess histopathologic changes in the gallbladder after sclerosis. MATERIALS AND METHODS: Percutaneous cholecystostomy and laser thermocoagulation of the cystic duct was performed in 13 pigs. Eight pigs underwent immediate gallbladder sclerosis with 95% ethanol and 3% sodium tetradecyl sulfate while two pigs received 95% ethanol only. The remaining three pigs served as controls. The cholecystostomy catheter was removed immediately after the procedure. All animals were sacrificed 6 weeks after laser thermocoagulation. Multiple sections through the gallbladder, which included the adjacent liver, the cystic duct, and the common bile duct, were obtained for histologic examination. RESULTS: At autopsy, the gallbladder in all 10 animals who underwent gallbladder sclerosis was reduced in size compared with controls. In all treated animals, the gallbladder mucosa was denuded; however, in nine of 10 cases reepithelialization had occurred. Complete sclerosis without reepithelialization was achieved in one pig who received both ethanol and sodium tetradecyl sulfate. In the two animals who received ethanol only, the depth of wall necrosis around the gallbladder lumen was less than in those pigs who received both ethanol and sodium tetradecyl sulfate. No pigs showed signs of hepatic necrosis or injury to the common bile duct. CONCLUSION: Cystic duct laser thermocoagulation allows immediate gallbladder sclerotherapy without injury to the common bile duct. Sclerosis with ethanol and sodium tetradecyl sulfate results in denudation of the gallbladder mucosa. However, a single therapeutic session with immediate removal of the cholecystostomy catheter was inadequate for gallbladder ablation in this model because of reepithelialization.

Animals↗
PubMed1991

Liver tumor imaging.

Liver tumor imaging is the paradigm of the dilemma of diagnostic decision-making in the current era of abundant high technology. In part, this is a reflection of the multiplicity of imaging techniques now in wide use worldwide. These include ultrasound (US), radionuclide scintigraphy (RNS), computed tomography (CT), magnetic resonance imaging (MRI), and techniques especially designed for staging the extent of known liver cancer, such as computed tomography during arterial portography (CTAP) and intraoperative ultrasound (IOUS). Most authorities concede that CT scanning is the single test most closely fitting the designation "gold standard" for liver tumor imaging, although MRI, a less mature technique, is already preferred by some. Local factors profoundly influence the selection and sequence of imaging studies, including available equipment, radiologic skills, institutional interests, and especially the specific clinical circumstances of the patient. Thus, diagnostic algorithms or decision trees for sequential imaging workup of liver tumor suspects tend to be somewhat institution specific.

Carcinoma, Hepatocellular↗
PubMed1991

Percutaneous contact dissolution of gallstones: complexity of radiologic care.

The clinical and technical considerations for successful gallstone dissolution with methyl tert-butyl ether (MTBE) are often underestimated. Patients are selected for MTBE therapy on the basis of a functioning gallbladder without evidence of acute inflammation or calcified stones at plain radiography. A transhepatic route is favored for percutaneous insertion of the cholecystostomy catheter because of the theoretic reduced frequency of bile leakage. MTBE is delivered manually through the catheter in a closed system, with dissolution times of 4-16 hours. After MTBE dissolution, residual debris in the gallbladder is present at follow-up sonography in up to 75% of patients. The high frequency of residual debris, the potential for stone recurrence, and the labor-intensive nature of MTBE therapy make its future uncertain, especially with the advent of laparoscopic cholecystectomy.

Cholelithiasis↗
PubMed1991

Preclinical evaluation of MnDPDP: new paramagnetic hepatobiliary contrast agent for MR imaging.

Manganese(II)-N,N'-dipyridoxylethylenediamine-N,N'-diacetate-5,5'-bis (phosphate) (MnDPDP) is a paramagnetic complex designed for use as a hepatobiliary agent. The T1 relaxivity of MnDPDP (2.8 [mmol/L]-1.sec-1 in aqueous solution) was similar to that of gadolinium diethylenetriaminepentaacetic acid (DTPA) (4.5 [mmol/L]-1.sec-1) and gadolinium tetraazocyclodecanetetraacetic acid (DOTA) (3.8 [mmol/L]-1.sec-1). However, in liver tissue the T1 relaxivity of MnDPDP (21.7 [mmol/L]-1.sec-1) was threefold higher than that reported for Gd-DOTA (6.7 [mmol/L]-1.sec-1). Maximum liver T1 relaxation enhancement occurred 30 minutes after injection of MnDPDP, at which time 54MnDPDP biodistribution studies indicated that 13% of total body activity was in the liver. Enhanced (MnDPDP, 50 mumol/kg) MR images showed a fivefold increase in tumor-liver contrast-to-noise ratio over baseline unenhanced images. Results of the authors' acute and subchronic toxicity studies suggest that MnDPDP will be safe at the doses necessary for clinical imaging; at 10 mumol/kg, the safety factor (LD50/effective dose) for MnDPDP is 540, significantly greater than the safety factor of Gd-DTPA (ie, 60-100).

Animals↗
PubMed1991

Optimal technique for detection of gallstones at injection cholecystography: in vitro analysis.

Injection cholecystography is often employed during invasive gallbladder procedures to determine the number of gallstones that are present. The authors undertook this study to define the optimal radiographic technique for performance of injection cholecystography. Condoms filled with 100 mL of contrast medium at four different iodine concentrations (30%, 15%, 7.5%, and 3.8% [wt/vol]) and containing up to five 4-mm-thick gallstones or a single 10-mm-thick gallstone were radiographed in a 20-cm-deep water bath by using four kilovolt peak settings (70, 80, 90, and 100 kVp). Images were read by three radiologists who were blinded to the radiographic technique. significantly (P less than .05) improved Decreasing iodine concentration significantly (P less than .05) improved detection of 4-mm-thick gallstones at a constant kilovolt peak setting. However, increasing the kilovolt peak setting while using the same concentration of contrast medium had no statistically significant influence on gallstone detectability, although radiologists did indicate a preference for the high-kilovolt peak technique. Results of the authors' experiments showed that for detection of small gallstones at injection cholecystography, use of a low-concentration contrast medium and a high kilovolt peak setting is the recommended radiographic technique.

Cholecystography↗
PubMed1991

Focal nodular hyperplasia of the liver: MR findings in 35 proved cases.

MR images of 28 patients with 35 lesions of hepatic focal nodular hyperplasia were reviewed to determine the frequency of findings considered typical of this condition (isointensity on T1- and T2-weighted pulse sequences, a central hyperintense scar on T2-weighted images, and homogeneous signal intensity). Fifteen lesions were imaged at 0.6 T with T1- and T2-weighted spin-echo (SE) pulse sequences; 20 lesions were imaged at 1.5 T with T1-weighted SE and gradient-echo pulse sequences and T2-weighted SE pulse sequences. Diagnosis of focal nodular hyperplasia was made pathologically in 25 patients, with nuclear scintigraphy in four, and with follow-up imaging in six. Only seven lesions (20%) were isointense relative to normal liver on both T1- and T2-weighted images. On T1-weighted SE images, 21 lesions (60%) were isointense relative to normal liver, 12 (34%) were hypointense, and two (6%) were hyperintense. On T2-weighted SE images, 12 lesions (34%) were isointense and 23 (66%) were hyperintense relative to normal liver. A central scar was present in 17 lesions (49%) and was hypointense relative to the lesion on T1-weighted images and hyperintense on T2-weighted images. Twenty lesions (57%) were of homogeneous signal intensity throughout the lesion, except for the presence of a central scar. All three MR imaging characteristics were present in three cases (9%). We conclude that hepatic focal nodular hyperplasia has a wide range of signal intensity on MR imaging.

Adult↗
PubMed1991

Liver tumor imaging: current concepts.

With the increasing availability of curative surgical techniques for primary and secondary hepatic neoplasms, the tasks for clinical imaging of liver cancer suspects have become more exacting. Detection of tumor, differential diagnosis of individual nodules, and mapping the anatomic extensions of malignant disease are now routinely required. Related and unrelated liver substrate abnormalities such as cavernous hemangioma and focal fatty deposits are often discovered in liver cancer suspects and must be differentiated from metastatic deposits. Moreover, modern imaging methods frequently display tiny subcentimeter nodules which often prove difficult to adequately characterize (micrometastases vs other). The most sensitive imaging techniques are CT after arterial portography and intraoperative ultrasound, but because of their invasiveness, these are reserved exclusively for staging. For primary screening MR imaging is increasingly preferred over CT because of its superiority in discriminating hemangiomas and cysts from metastases without the need for iodinated contrast material.

Carcinoma, Hepatocellular↗
PubMed1991

Iron oxide enhanced MR imaging of the liver and spleen: review of the first five years.

Superparamagnetic iron oxide (SPIO) particles are a potent new class of MR contrast agents affording improved detection of hepatic and splenic neoplasms. In this report we review the development of this agent through preclinical studies and early clinical results at Massachusetts General Hospital during a 5 year investigation. SPIO particles are sequestered by normal reticuloendothelial system (RES) phagocytic Kupffer cells but are not retained in tumor tissue. Consequently, there is a five fold increase in T2 relaxation between normal RES tissue and tumor with a comparable advantage in quantitative signal to noise ratio, contrast to noise ratio and lesion detectibility in the liver and spleen at MR imaging. Increased lesion conspicuity can be exploited to decrease threshold size for lesion detection to less than 3 mm. Clinically beneficial effects occur with a variety of mildly T2-weighted spin-echo pulse sequences; gradient-echo techniques show even greater benefit after administration of SPIO. Metabolically, pharmaceutical grade preparations are biodegradable and bioavailable, being rapidly turned over into body iron stores and incorporated into erythrocyte hemoglobin. Early dose escalation clinical trials have identified a probable clinical dose range of 10-20 mumol Fe/kg body weight. SPIO compounds evaluated to date are still investigational in the United States. Newer commercial formulations currently being evaluated may extend clinical safety margins.

Ferric Compounds↗
PubMed1991

[Magnetic resonance tomographic diagnosis of a myelolipoma of the adrenal glands].

Myelolipoma is an uncommon, benign, adrenal lesion composed of fatty tissue and bone marrow elements. The presence of fat within this tumor is the key factor in identification and noninvasive diagnosis with imaging methods. Since fat has a characteristic behavior reflected by the MR signal intensity, a specific diagnosis can be made by MRI.

Adrenal Gland Neoplasms↗
PubMed1990

Clinical application of superparamagnetic iron oxide to MR imaging of tissue perfusion in vascular liver tumors.

Previous studies of AMI-25, a particulate iron oxide magnetic resonance contrast agent, imaged liver tumors 1 or more hours after injection, in the retention phase after complete clearance of AMI-25 from the circulation. In the present study, imaging was performed in the distribution phase, during the first 12 minutes after injection while contrast agent remain in circulation, and these images were compared with those obtained in the retention phase. Nineteen patients with cancer were studied, including 15 imaged during the distribution phase. T2-weighted distribution phase images demonstrated 90% of the lesions detected by means of T2-weighted retention phase images, showed a 3.5-fold increase in contrast-to-noise ratio over images obtained before administration of AMI-25, and increased diagnostic confidence by reducing signal from small intrahepatic blood vessels. Distribution phase images showed little contrast agent uptake by cancer tissue. Both distribution and retention phase images demonstrated greater contrast agent uptake by hemangiomas than by malignant neoplasms (P less than .01). The use of both distribution phase and retention phase AMI-25-enhanced images offers improved diagnostic accuracy in the detection and characterization of focal liver lesions.

Adenocarcinoma↗
PubMed1990

Gallstone fragmentation with contact electrohydraulic lithotripsy: in vitro study of physical and technical factors.

To identify physical and technical factors that have an effect on fragmentation, the authors performed in vitro contact electrohydraulic lithotripsy (EHL) on gallstones 10 mm or larger in size. Of 122 gallstones, 113 (93%) could be fragmented with 1-46 pulses from a 3-F electrode (average, 10 pulses). Only 12 of the 113 stones could be fragmented with a single spark. Of the nine stones that did not fragment with 50 pulses from a 3-F electrode, four were larger than 30 mm in diameter, and five were seen at radiography to be heavily calcified; all of these stones were fragmented with five or fewer pulses from a 9-F electrode. Stone capture in a wire basket facilitated fragmentation of gallstones of all sizes, but particularly those stones 15 mm or larger. Contact EHL could be performed as well in a 1:1 dilute diatrizoate irrigating solution as in 1:6 normal saline. A significantly greater number of pulses was required to fragment gallstones 15 mm in diameter or larger compared with stones smaller than 15 mm (P less than .01). In addition, stones 15 mm or smaller had a greater tendency to fragment into "gravel" (ie, fragments measuring 2 mm or less), while EHL of stones larger than 15 mm produced larger, discrete fragments of approximately equal size (P less than .05). EHL of heavily calcified gallstones required a significantly greater number of pulses than EHL of less calcified or noncalcified stones (P less than .002).

Cholelithiasis↗