Axonal branching pattern of neurons of the subthalamic nucleus in primates

Axonal projections arising from the subthalamic nucleus (STN) in cynomolgus monkeys (Macaca fascicularis) were traced after labeling small pools (5-15 cells) of neurons with biotinylated dextran amine. Seventy-five single axons were reconstructed from serial sagittal sections with a camera lucida. Most of the STN labeled cells displayed five to eight long, sparsely spined dendrites that arborized mostly along the main axis of the nucleus. Based on their axonal targets, five distinct types of STN projection neurons have been identified: 1) neurons projecting to the substantia nigra pars reticulata (SNr), the internal (GPi) and external (GPe) segments of the globus pallidus (21.3%); 2) neurons targeting SNr and GPe (2. 7%); 3) neurons projecting to GPi and GPe (48%); 4) neurons targeting GPe only (10.7 %); and 5) neurons with axons that coursed toward the sriatum, but whose terminal arborization could not be visualized in detail (17.3%). Axons of the first two types bifurcated into rostral subthalamopallidal and caudal pallidonigral branches. However, the majority of STN axons had only a single branch that coursed rostrally toward the pallidum and striatum. These results reveal that, in contrast to current beliefs, the primate STN is not a monolithic entity. This nucleus harbors several subtypes of projection neurons, each endowed with a highly patterned set of collaterals. This organization allows STN neurons to exert a multifarious effect not only on the GPe, with which the STN is reciprocally connected, but also on the two major output structures of the basal ganglia, the SNr and the GPi.

Biodegradation of pentachlorophenol in a continuous anaerobic reactor augmented with Desulfitobacterium frappieri PCP-1

In this work, a strain of anaerobic pentachlorophenol (PCP) degrader, Desulfitobacterium frappieri PCP-1, was used to augment a mixed bacterial community of an anaerobic upflow sludge bed reactor degrading PCP. To estimate the efficiency of augmentation, the population of PCP-1 in the reactor was enumerated by a competitive PCR technique. The PCP-1 strain appeared to compete well with other microorganisms of the mixed bacterial community, with its population increasing from 10(6) to 10(10) cells/g of volatile suspended solids within a period of 70 days. Proliferation of strain PCP-1 allowed for a substantial increase of the volumetric PCP load from 5 to 80 mg/liter of reaction volume/day. A PCP removal efficiency of 99% and a dechlorination efficiency of not less than 90.5% were observed throughout the experiment, with 3-Cl-phenol and phenol being observable dechlorination intermediates.

Moderate alcohol consumption: the gentle face of Janus

OBJECTIVES

The regular consumption of alcohol in moderate amounts (defined in North America as up to 2 drinks per day for men and 1 drink per day for females) has been recognized in the last decade as a negative risk factor for atherosclerosis and its clinical sequelae: coronary heart disease (CHD), ischemic stroke, and peripheral vascular disease. Mortality and morbidity attributable to CHD are 40-60% lower in moderate drinkers than among abstainers. Among the mechanisms accounting for these reductions, increased circulating concentrations of HDL-cholesterol and inhibition of blood coagulation appear to be paramount. Additional benefits are, in certain beverages, conferred by the presence of constituents other than alcohol (e.g., flavonoids and hydroxystilbenes), which prevent oxidative damage, free radical formation, and elements of the inflammatory response.

CONCLUSIONS

A number of other diseases appear to be beneficially modulated by moderate alcohol consumption based on epidemiologic surveys and, in some instances, experimental evidence. These include duodenal ulcer, gallstones, enteric infections, rheumatoid arthritis, osteoporosis, and diabetes mellitus (type II). Compared with abstainers, moderate drinkers exhibit improved mental status characterized by decreased stress and depression, lower absenteeism from work, and decreased incidence of dementia (including Alzheimer's disease). Although limits of safe drinking have been conservatively defined, it is regrettable that political considerations are hampering the clinical application of this knowledge and its dissemination to the lay public.

Quality care for cardiology patients

To evaluate outcome measures in a cardiology unit, patient satisfaction was measured. Patients consistently related problems in two areas: pain management and the waiting period before their procedure. After a major system change, patient satisfaction increased 16% and 29% respectively.

Frequency of expression of prostate-specific antigen mRNA in lung tumors

The presence of prostate-specific antigen (PSA) protein and messenger RNA (mRNA) was studied in 52 primary lung tumor tissues. The PSA protein was detected more frequently and at higher levels in lung tumor extracts from men. The levels of PSA protein in tumor extracts correlated with preoperative and postoperative serum PSA levels, suggesting a possible contamination of the tumor extracts with PSA from residual blood in the tumor vasculature. The PSA mRNA was detected by reverse transcription-polymerase chain reaction (RT-PCR) and Southern blot hybridization in 24 (68%) of 35 tumors from men, in 9 (53%) of 17 tumors from women, and in 5 (71%) of 7 adjacent normal lung tissue specimens. The levels of PSA protein did not associate with patient age, the tumor stage, grade, or histologic type, or the nodal status. Similarly, PSA mRNA was not associated with any clinicopathologic variables, but squamous cell carcinomas, especially in men, were more frequently positive. A by-product of the RT-PCR procedure was cloned and sequenced and found to be a 450-base pair sequence not previously deposited in the data bank. We conclude that PSA mRNA and protein frequently can be detected in lung tumors and normal tissues from men and women but at levels much lower than those seen in breast carcinomas in women. The significance of the new 450-base pair sequence remains to be determined.

Time course of training-induced changes in maximal exercise of short duration in men and women

The purpose of the present study was to test the hypothesis that gender differences are present in the extent and time course of exercise training-induced changes in maximal 10- and 90-s performance test. Thirty-six sedentary subjects (19 women and 17 men) were submitted to 15 weeks of training involving both continuous and interval ergocycle exercise sessions, while 13 other subjects (5 women and 8 men) served as a control group. Maximal power output after 10 s (P10) and 90s (P90) of cycling exercise was measured before and at each 5-week interval of the 15-week training period in both groups. Significant (p < 0.01) training-induced increases in performance were noted after 5 weeks, 10 weeks and 15 weeks of training for P10, and after 5 and 10 weeks for P90 in both genders. P10 and P90 were significantly increased in both genders (about 25% in men and 35% in women) following the 15-week training program and overall absolute increases were not statistically different between men and women. Slight increases (about 5%) in performance tests were observed in control subjects, but only during the first 5-week interval. P10 and P90 of women expressed as a percentage of that of men remained the same throughout the 15-week program. No significant relationship between pre-training values of P10 and their responses to training was found in men and women. In conclusion, results of the present study indicate that women have the same capacity to increase maximal short-term performance in response to training in comparison to men.

Glutamate currents in morphologically identified human dentate granule cells in temporal lobe epilepsy

Glutamate-receptor-mediated synaptic transmission was studied in morphologically identified hippocampal dentate granule cells (DGCs; n = 31) with the use of whole cell patch-clamp recording and intracellular injection of biocytin or Lucifer yellow in slices prepared from surgically removed medial temporal lobe specimens of epileptic patients (14 specimens from 14 patients). In the current-clamp recording, low-frequency stimulation of the perforant path generated depolarizing postsynaptic potentials that consisted of excitatory postsynaptic potentials and phase-inverted inhibitory postsynaptic potentials mediated by the gamma-aminobutyric acid-A (GABA(A)) receptor at a resting membrane potential of -62.7 +/- 2.0 (SE) mV. In the voltage-clamp recording, two glutamate conductances, a fast alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA)-receptor-mediated excitatory postsynaptic current (EPSC; AMPA EPSC) and a slowly developing N-methyl-D-aspartate (NMDA)-receptor-mediated EPSC (NMDA EPSC), were isolated in the presence of a GABA(A) receptor antagonist. NMDA EPSCs showed a voltage-dependent increase in conductance with depolarization by exhibiting an N-shaped current-voltage relationship. The slope conductance of the NMDA EPSC ranged from 1.1 to 9.4 nS in 31 DGCs, reaching up to twice the size of the AMPA conductance. This widely varying size of the NMDA conductance resulted in the generation of double-peaked EPSCs and a nonlinear increase of the slope conductance of up to 37.5 nS with positive membrane potentials, which resembled "paroxysmal currents," in a subpopulation of the neurons. In contrast, AMPA EPSCs, which were isolated in the presence of an NMDA receptor antagonist (2-amino-5-phosphonovaleric acid), showed voltage-independent linear changes in the current-voltage relationship and were blocked by 6-cyano-7-nitroquinoxaline-2,3-dione. The AMPA conductance showed little variance, regardless of the size of the NMDA conductance of a given neuron. The average AMPA slope conductance was 5.28 +/- 0.65 (SE) nS in 31 human DGCs. This value was similar to AMPA EPSC conductances in normal rat DGCs (5.35 +/- 0.52 nS, mean +/- SE; n = 55). Dendritic morphology and spine density were quantified in the individual DGCs to assess epileptic pathology. Dendritic spine density showed an inverse correlation (r2 = 0.705) with a slower rise time and a longer half-width of the excitatory postsynaptic potentials mediated by the NMDA receptor. It is concluded that both AMPA and NMDA EPSCs contribute to human DGC synaptic transmission in epileptic hippocampus. However, a wide range of changes in the slope conductance of the NMDA EPSCs suggests that the NMDA-receptor-mediated conductance could be altered in human epileptic DGCs. These changes may influence the generation of chronic subthreshold epileptogenic synaptic activity and give rise to pathological excitation leading to epileptic seizures and dendritic pathology.

Electroconvulsive therapy (ECT) for intractable depression following epilepsy neurosurgery

Psychopathology following epilepsy neurosurgery is a significant risk. Treatment modalities have not been addressed in the literature. As disproportionately elevated suicide rates have been reported, it is critical to treat aggressively any psychiatric illness wherein suicidal ideation is a key component. This case reports the safe utilization of electroconvulsive therapy (ECT) for intractable depression following epilepsy neurosurgery (24 references).

Changes in health after elective percutaneous coronary revascularization. A comparison of generic and specific measures

OBJECTIVES

This study determines changes in health-related quality of life after elective percutaneous transluminal coronary angioplasty and compares generic and specific measures.

METHODS

Changes in health-related quality of life were measured in consecutive, symptomatic patients undergoing elective percutaneous coronary revascularization using the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36), the Specific Activity Scale (SAS), and the Canadian Cardiovascular Society Classification (CCSC). The patients were interviewed as outpatients before admission and at least 6 months later.

RESULTS

There were significant changes in the following SF-36 measures: physical functioning (postscore minus prescore = 19.1 +/- 24.1), role limitations due to physical-health problems (40.4 +/- 47.2), bodily pain (19.9 +/- 29.3), vitality (12.9 +/- 25.1), social functioning (20.0 +/- 33.1), role limitations due to emotional-health problems (26.7 +/- 49.0), and general mental health (7.1 +/- 21.2). General health perceptions did not change significantly. Internal-consistency reliability coefficients for these measures ranged from 0.73 to 0.91. There also was significant improvement in the CCSC class, but the SAS class did not change significantly. Overall, the SF-36 role-physical scale was the most responsive to changes after elective percutaneous coronary revascularization, followed by the CCSC and the SF-36 physical functioning scale.

CONCLUSIONS

Although this study cannot determine the causal role of elective percutaneous coronary revascularization in these changes, it provides support for the usefulness of these measures in future evaluations of this intervention.

Coronary restenosis

Return of angina within 6 months of a catheter-based treatment of coronary artery disease usually reflects restenosis due to an overly aggressive local healing response to the procedure-related arterial injury. The restenotic lesion should be treated aggressively. Patients with preexisting diabetes mellitus, renal failure requiring hemodialysis, and left anterior descending artery lesions should be considered to be at exceedingly high risk for clinically significant restenosis. Exercise testing is indicated for all patients who experience a return of their angina within 6 months of an interventional procedure. Nurse practitioners in the primary care setting may be the first clinicians to hear of the return of angina. Patients should always be reassured that repeat intervention is almost always possible and is generally effective in providing long-term relief. New devices (in particular the Palmaz-Schatz stent) may help reduce the likelihood of restenosis, to the extent that they provide a large acute post-treatment lumen diameter that is more tolerant of intimal hyperplasia without producing significant narrowing. Until adjunctive drug therapy is found that effectively reduces the local tissue response to interventional therapy, all clinicians involved in caring for patients following such procedures will need to be vigilant and knowledgeable about recognizing and treating restenosis.

Prostate specific antigen in breast cancer, benign breast disease and normal breast tissue

Prostate specific antigen (PSA) is a tumor marker used widely for the diagnosis and monitoring of prostatic adenocarcinoma. Recently, we provided evidence that PSA may also be produced by breast tumors. In this report we examined quantitatively the PSA levels in 199 breast tumors, 48 tissues with benign breast disease (BBD, 34 fibroadenomas), and 36 normal breast tissues. Significant amounts of PSA (> or = 0.030 ng of PSA per mg of total protein) were found in 28% of breast tumors, 65% of BBD tissues, and 33% of normal breast tissues. PSA positivity in breast tumors was highest in stage I disease (34%) and decreased with disease stage (24% in stage II and 18% in stage III-IV). Using polymerase chain reaction amplification we have shown PSA mRNA presence in patients with PSA protein-positive tissues (benign and malignant) but not in patients with PSA protein-negative tissues. Our data suggest that PSA is expressed frequently by normal breast tissue, by tissue of benign breast diseases, and by breast cancer tissue. Highest expression is seen in benign breast disease and lowest expression in advanced stage cancerous tissue. As PSA production is mediated by steroid hormones and their receptors, we propose that PSA may be a new marker of steroid hormone action in the normal or diseased female breast. The role of this enzyme in the development of breast diseases including breast cancer is currently unknown.

Corticostriatal projections from layer V cells in rat are collaterals of long-range corticofugal axons

Corticostriatal projections arising from the infragranular layers of the motor and second somatosensory cortices were studied in rats after labeling small pools of neurons with biocytin. Camera lucida reconstruction of 263 fibers arising from laminae V and VI revealed that all corticostriatal projections derive from collaterals of lamina V cells whose main axons descend into the cerebral peduncle. In contrast, lamina VI cells do not branch upon the striatum, but upon the thalamus. Together with the results obtained in previous tracing studies, the present data raise the possibility that no neuron is exclusively corticostriatal. We therefore propose that all corticostriatal projections are collaterals given off by the axons of two types of neurons: layer V cells whose main axon project to the brainstem and/or spinal cord, and layer III cells that project to the contralateral hemisphere.

Expression of the prostate-specific antigen gene by a primary ovarian carcinoma

We describe a patient with primary ovarian carcinoma that developed after liver transplantation whose tumor was highly positive for prostate-specific antigen (PSA). PSA in tumor tissue was characterized by two immunoassays, HPLC, immunohistochemistry, reverse transcription-PCR, Southern blotting, and DNA sequencing. PSA in the ovarian tumor was present as free, M(r) 33,000 protein (> 90%) and as PSA bound to alpha 1-antichymotrypsin (M(r) 100,000; < 10%). Immunohistochemistry localized PSA in the cytoplasm of epithelial cells of the tumor. Two separate reverse transcription-PCRs for PSA amplified the expected products which hybridized specifically to a PSA cDNA probe on Southern blots. Sequencing of the PCR products, representing the whole coding sequence of the PSA gene, revealed identity with the sequence of PSA cDNA from prostate tissue. These data suggest that the PSA produced by the ovarian tumor was identical in molecular weight and sequence to prostatic PSA. Based on data of tissue culture experiments with breast carcinoma cell lines, we speculate that the PSA gene in the tumor of this patient was up-regulated by the therapeutically administered glucocorticoids after liver transplantation.

Haemoperitoneum due to spontaneous rupture of hepatic haemangiomatosis: treatment by superselective arterial embolization and partial hepatectomy

A case is reported of a 36-year-old woman with haemoperitoneum due to spontaneous rupture of hepatic haemangiomatosis. Computed tomography showed a subcapsular hepatic mass in the posterior segment of the right hemiliver (subsegment 7) containing a fluid-fluid level. Magnetic resonance imaging depicted a subcapsular hepatic mass displaying an internal fluid-fluid level suggestive of haematoma. Hepatic angiography showed an intense arterial blush in the area of the subsegment 7 and permitted a subsequent and temporarily effective superselective transcatheter embolization of the subsegmental arterial branch for subsegment 7. Because of a recurrence of intraperitoneal haemorrhage 15 days after the first embolization, a new selective hepatic artery embolization was performed. However, intraperitoneal haemorrhage recurred 10 days after the second embolization, and the patient underwent resection of the posterior segments of the right hemiliver (subsegments 6 and 7). This case suggests that superselective arterial embolization, when used alone, does not provide a permanent treatment of haemoperitoneum due to spontaneous rupture of hepatic haemangiomatosis. However, this technique seems to be useful in avoiding an emergency surgery, allowing a planned hepatic resection.

Prostate-specific antigen expression by various tumors

There is a growing body of evidence indicating that prostate-specific antigen (PSA) may be present in many steroid hormone-stimulated epithelial tissues other than that of the prostate. In particular, breast tumor cell lines treated with steroid hormone receptor agonists, breast tumors, and normal human breast have recently been found by our group to contain PSA. To investigate whether PSA may also be present in other human tumors, we employed a highly sensitive immunofluorometric assay technique to quantify PSA immunoreactivity in tumor extracts. Using a PSA-positivity cutoff value of 0.005 ng per mg of protein, 23 of 43 diverse tumors tested positive for PSA protein. Confirmatory analyses for PSA by a commercially available method (IMx) on six samples demonstrated a high degree of concordance between the two methods. To establish the molecular weight of the immunoreactive species, the most highly positive tumor extracts of each tumor type were fractionated by high performance liquid chromatography. Whereas the majority of tumors had immunoreactivity eluting at both 100 KDa and 33 KDa, corresponding to PSA bound to alpha 1-antichymotrypsin and free PSA, respectively, the colon and parotid tumors displayed immunoreactivity only at the 33 KDa fraction. We conclude that in addition to breast tumors and normal breast, colon, ovarian, liver, kidney, adrenal, and parotid tumors can also produce PSA. The physiological role of PSA in these tumors is currently under investigation.

Immunoreactive prostate-specific antigen in lung tumors

Prostate-specific antigen (PSA) is a glycoprotein produced by the epithelial cells of the prostate. PSA is currently used clinically to diagnose and monitor prostate carcinoma. In previous work we have demonstrated that 30% of breast tumors and, more rarely other tumors, contain significant amounts of PSA. PSA appears to be a favorable prognostic indicator in breast cancer. Here, using a sensitive assay, we demonstrated for the first time that lung adenocarcinomas and squamous cell carcinomas also contain PSA. PSA in lung tumor extracts was present mainly in its 33 KDa form (free PSA), at levels measurable by commercial methods. The presence of PSA was associated more closely with male patients and adenocarcinomas. The physiological role of PSA in lung tissue and the prognostic significance of PSA in lung cancer remain to be determined. These and our previous data as well as reports by other groups support the view that PSA is a ubiquitous biochemical marker of steroid hormone action.

Involvement of superior mesenteric vessels and portal vein in pancreatic adenocarcinoma: detection with CT during arterial portography

A prospective study was designed to determine the utility of computed tomography (CT) during arterial portography (CTAP) in the detection of superior mesenteric vessels and portal vein involvement in patients with pancreatic adenocarcinoma. Eighteen patients with adenocarcinoma of the head of the pancreas and eight patients with benign pancreatic disease were investigated with CTAP, dynamic contrast-enhanced CT, and angiography. Appropriate review was made to determine presence or absence of superior mesenteric vessels and portal vein involvement. Final diagnosis was obtained in all cases by surgical explorations. The overall accuracy rate for detecting or excluding superior mesenteric vessels and portal vein involvement was 96% (25 of 26 patients) with CTAP, 88% (23 of 26 patients) with dynamic contrast-enhanced CT, and 85% (22 of 26 patients) with angiography. No statistically significant difference in accuracy was found among the three techniques. Our results suggest that the use of CTAP is not indicated in the preoperative detection of superior mesenteric vessels and portal vein involvement in patients with pancreatic adenocarcinoma.

MRI of Budd-Chiari syndrome

A retrospective study was undertaken to reassess the various magnetic resonance imaging (MRI) features of Budd-Chiari syndrome (BCS). MRI examinations of 22 patients with pathologically confirmed BCS were studied. Spin-echo (SE) T1- (TR = 300-450 ms/TE = 12-15 ms), and SE T2-weighted (TR = 1600-2000 ms/TE = 30-60/90-120 ms) MRI images were obtained in all patients. Gradient-recalled-echo (GRE) images (TR = 7-60 ms/TE = 3-19 ms, flip angle = 10-40 degrees) were obtained in 14 patients. MRI showed thrombosis of three or two hepatic veins in 19 (86%) and 3 (14%) patients, respectively. Spontaneous intrahepatic anastomoses was depicted in five (23%) patients. Ascites appeared in 15 patients (68%). Thrombosis or external compression of the inferior vena cava (IVC) by an enlarged caudate lobe was depicted in six (27%) and five (23%) patients, respectively. Prominent azygos and hemiazygos veins were demonstrated in seven (32%) patients (six of whom had thrombosis of the IVC). MRI showed hepatomegaly in all patients and enlarged caudate lobe in 18 (82%) patients. SE T1- and SE T2-weighted MRI images revealed inhomogeneous signal intensity of hepatic parenchyma in 14 (64%) patients. SE T1- and SE T2-weighted MRI images showed homogeneous signal intensity of hepatic parenchyma in eight (36%) patients. Our results demonstrate that BCS displays various features on MRI images, and such information is important for diagnosis.

Detection of recurrent hepatic metastases after partial hepatectomy: value of CT combined with arterial portography

OBJECTIVE

We did a retrospective study to evaluate the sensitivity of CT combined with arterial portography in detecting recurrent hepatic metastases after partial hepatectomy.

MATERIALS AND METHODS

CT scans combined with arterial portography in 18 patients who had partial hepatectomy and suspected intrahepatic recurrence of metastases were retrospectively reviewed. Eleven of the patients had further surgery, and recurrent hepatic metastases were proved; seven patients were inoperable. The sensitivity of CT with arterial portography for detecting recurrent intrahepatic metastases was determined and correlated with intraoperative findings and findings on follow-up imaging studies in the 11 patients (with a total of 23 hepatic metastases) who had further surgery.

RESULTS

Not one of the 18 CT examinations combined with arterial portography was compromised by inhomogeneous perfusion of contrast material in the portal vein. Of the 23 metastases that were found in the 11 patients who had further surgery, 21 (91%) were shown on CT with arterial portography. In two patients, CT with arterial portography showed two subcapsular hypoattenuating pseudolesions that were correctly identified as nontumorous perfusion defects, as confirmed by intraoperative findings and follow-up imaging studies.

CONCLUSION

This study shows that postoperative CT with arterial portography is efficacious in the detection of intrahepatic recurrent metastases in patients who have had a partial hepatectomy. Furthermore, prior partial hepatectomy does not compromise the quality of this examination.

Cystic tumors of the pancreas: dynamic CT studies

OBJECTIVE

Our retrospective study was performed to reassess the common dynamic CT manifestations of cystic tumors of the pancreas and to determine whether they might allow the differentiation between benign and malignant tumors.

MATERIALS AND METHODS

Dynamic CT examinations of 19 patients with 20 cystic tumors of the pancreas, including 7 serous cystadenomas, 3 benign mucinous cystadenomas, 5 mucinous cystadenocarcinomas, 3 mucin-producing duct ectasias, and 2 papillary cystic epithelial neoplasms, were retrospectively reviewed. The examinations were obtained with 4 to 5 mm collimation with intravenous injection of 120-130 ml of contrast agent.

RESULTS

Calcifications were found only in benign tumors (seven serous cyst-adenomas). Internal septations were found in benign and malignant tumors (seven serous cystadenomas, three benign mucinous cystadenomas, three mucinous cystadenocarcinomas). Solid excrescences within cystic cavities were found only in malignant tumors (two mucinous cystadenocarcinomas, two mucin-producing duct ectasias). Dynamic CT features allowed the distinguishing of serous cystadenomas from other cystic tumors and mucin-producing duct ectasias from other mucinous tumors. Dynamic CT features did not permit differentiation between benign mucinous cystadenomas, mucinous cystadenocarcinomas, and papillary cystic epithelial neoplasms.

CONCLUSION

The review suggests that dynamic CT findings are useful to differentiate (a) serous cystadenomas and mucin-producing duct ectasias from other cystic tumors of the pancreas and (b) benign from malignant tumors. Such differentiation has impact on patient management.

CT of hepatic tumors: prevalence and specificity of retraction of the adjacent liver capsule

OBJECTIVE

The purpose of this study was to describe the CT features of capsular retraction of the liver adjacent to hepatic tumors and to test the hypothesis that this finding is specific for malignant hepatic tumors.

MATERIALS AND METHODS

We first retrospectively reviewed the CT scans of eight patients with pathologically proved malignant hepatic tumors (five secondary and three primary) who had CT scans that showed retraction of the overlying liver capsule. Then, using criteria developed from the first eight cases, we prospectively studied 253 patients with pathologically proved hepatic tumors (75 benign, 178 malignant) to determine the prevalence of retraction of the liver capsule shown by CT and the specificity of this finding for malignant hepatic tumors.

RESULTS

CT scans in the first eight patients showed two types of capsular retraction. In seven patients, the retracted liver capsule was smooth and regular. In one patient, capsular retraction was associated with central ulceration extending to and eroding the liver capsule. Four of 253 patients studied prospectively had hepatic tumors with associated capsular retraction (prevalence, 2%). In those four cases, the retracted liver capsule was smooth and regular. All four tumors were malignant (one fibrolamellar hepatocellular carcinoma, two carcinoid tumors, one colorectal metastasis).

CONCLUSION

Capsular retraction of the liver adjacent to hepatic tumors is an uncommon CT finding that appears to be specific for malignant hepatic tumors.

Focal hepatic masses: comparison of detection during arterial portography with MR imaging and CT

PURPOSE

A prospective study was performed to compare the sensitivity and specificity of magnetic resonance (MR) imaging and computed tomography (CT) both performed during arterial portography in depicting focal hepatic masses.

MATERIALS AND METHODS

Eleven patients with 31 pathologically proved focal hepatic masses were prospectively evaluated. MR arterial portography was performed with 4 mL of a 0.5 mmol/kg solution of gadolinium tetraazacyclododecanetetraacetic acid (DOTA) injected through a catheter into the superior mesenteric artery during multisection gradient-echo imaging.

RESULTS

MR arterial portography depicted 29 of the 31 masses (sensitivity, 94%). CT arterial portography depicted 27 of the 31 masses (sensitivity, 87%). Two masses not depicted with either CT or MR had a diameter of 3 and 7 mm, respectively. Neither MR nor CT demonstrated a false-positive finding (specificity, 100%). The difference in sensitivity and specificity between the two techniques was not statistically significant.

CONCLUSION

MR arterial portography does not enable detection of significantly more focal hepatic masses than does CT arterial portography.