MR imaging of small hepatocellular carcinoma (< or = 20 mm)--correlation with vascularity and histological features

We have evaluated the efficacy of magnetic resonance (MR) imaging for detecting hepatocellular carcinoma less than 20 mm in diameter (sHCC). This study involved 72 cases of sHCC tumors which were also investigated by angiography and histology. These cases were retrospectively examined for correlations between tumor stain (vascularity) on angiography, histological features (fat deposition, clear cells and the grade of differentiation) and the findings on T1 and T2 weighted MR imaging. The sHCC detection rate by MR imaging was 73.6% (53 cases) and by angiography was 59.7% (43 cases). Thirty-five cases were detected both the MR imaging and by angiography. The main MR imaging patterns were hypo to isointense on T1 weighted images (T1WI) and hyperintense on T2 weighted images (T2WI) in 22 cases, and hyperintense on both T1WI and T2WI in 7. In 18 cases which were not demonstrated by tumor staining on angiography, the main MR imaging patterns were hyperintense on T1WI and isointense on T2WI in 14. The histological features included fat deposition in 22 cases, 20 cases of which were hyperintense on T1WI, and 10 of these 20 were hyperintense on both T1WI and T2WI. Fat deposition was marked in 9. According to the grade of differentiation, 23 of the 26 cases with well differentiated HCC tumors were hyperintense on T1WI, and 21 of the 27 cases with moderately to poorly differentiated HCC were hypo to isointense on T1WI and hyperintense on T2WI. sHCC was visualized by MR imaging, reflecting vascularity, fat deposition and the grade of differentiation. In particular, MR imaging is useful for a differential diagnosis between the well differentiated HCC and the moderately to poorly differentiated HCC, and useful for the diagnosis of an early HCC.     

Mitral valve protrusion assessed by use of B-mode echocardiography in dogs with mitral regurgitation

OBJECTIVES: The purpose of this study ws to assess whether a community program begun in March 1988 that organized multiple city departments and private citizens could reduce alcohol-impaired driving, related driving risks, and traffic deaths and injuries. METHODS: Trends in fatal crashes and injuries per 100 crashes were compared in Saving Lives Program cities and the rest of Massachusetts from March 1984 through February 1993. In annual roadside surveys conducted at randomly selected locations, safety belt use among occupants of 54577 vehicles and travel speeds of 118442 vehicles were observed. Four statewide telephone surveys (n = 15188) monitored self-reported driving after drinking. RESULTS: In program cities relative to the rest of Massachusetts during the 5 program years in comparison with the previous 5 years, fatal crashes declined 25%, from 178 to 120, and fatal crashes involving alcohol decreased 42%, from 69 to 36. Visible injuries per 100 crashes declined 5%, from 21.1 to 16.6. The proportions of vehicles observed speeding and teenagers who drove after drinking were cut in half. CONCLUSIONS: Interventions organized by multiple city departments and private citizens can reduce driving after drinking, related driving risks, and traffic deaths and injuries.     

Prevalence of hyperapobetalipoproteinemia and other lipoprotein phenotypes in men (aged < or = 50 years) and women (< or = 60 years) with coronary artery disease

The prevalence and clinical characteristics of hyperapobetalipoproteinemia (hyperapoB) and other phenotypes of dyslipoproteinemia were examined in 99 men (aged < or = 50 years) and 104 women (< or = 60 years) undergoing elective diagnostic coronary arteriography. HyperapoB was the most common phenotype (34%) associated with premature coronary artery disease (CAD). Only 20.2% of patients with CAD had a normal lipoprotein phenotype. The significant odds ratios for CAD were as follows: hypertriglyceridemic hyperapoB 17.45 (p < 0.0001), type IV 6.54 (p = 0.0001), type IIa 4.73 (p = 0.008), normotriglyceridemic hyperapoB 2.54 (p = 0.03) and type IIb 8.73 (p = 0.05). The strong association of hypertriglyceridemic hyperapoB with CAD reflected the multiplicative effect of increased low-density lipoprotein apolipoprotein B and endogenous hypertriglyceridemia, and was independent of the effects of age, sex, diabetes mellitus, systemic hypertension, body mass index and cigarette smoking. The ratio of apolipoprotein B to A-1 was better than those of low-density to high-density lipoprotein cholesterol and total to high-density lipoprotein cholesterol at discriminating dyslipidemic phenotypes from normal. Obesity was increased approximately 1.5 to two-fold in the hypertriglyceridemic phenotypes, diabetes was more prevalent in hypertriglyceridemic hyperapoB (6.8-fold; p < 0.001) and type IV (4.4-fold; p = 0.02), and hypertension was increased 1.5- to twofold in most dyslipidemic groups. The data indicate that hyperapoB and endogenous hypertriglyceridemia both contribute to the risk of premature CAD.     

Simultaneous determination of aortic valve area by the Gorlin formula and by transesophageal echocardiography under different transvalvular flow conditions. Evidence that anatomic aortic valve area does not change with variations in flow in aortic stenosis

OBJECTIVES: The purpose of this study was to determine the impact of changes in flow on aortic valve area (AVA) as measured by the Gorlin formula and transesophageal echocardiographic (TEE) planimetry. BACKGROUND: The meaning of flow-related changes in AVA calculations using the Gorlin formula in patients with aortic stenosis remains controversial. It has been suggested that flow dependence of the calculated area could be due to a true widening of the orifice as flow increases or to a disproportionate flow dependence of the formula itself. Alternatively, anatomic AVA can be measured by direct planimetry of the valve orifice with TEE. METHODS: Simultaneous measurement of the planimetered and Gorlin valve area was performed intraoperatively under different hemodynamic conditions in 11 patients. Left ventricular and ascending aortic pressures were measured simultaneously after transventricular and aortic punctures. Changes in flow were induced by dobutamine infusion. Using multiplane TEE, AVA was planimetered at the level of the leaflet tips in the short-axis view. RESULTS: Overall, cardiac output, stroke volume and transvalvular volume flow rate ranged from 2.5 to 7.3 liters/min, from 43 to 86 ml and from 102 to 306 ml/min, respectively. During dobutamine infusion, cardiac-output increased by 42% and mean aortic valve gradient by 54%. When minimal flow was compared with maximal flow, the Gorlin area varied from (mean +/- SD) 0.44 +/- 0.12 to 0.60 +/- 0.14 cm2 (p < 0.005). The mean change in Gorlin area under different flow rates was 36 +/- 32%. Despite these changes, there was no significant change in the planimetered area when minimal flow was compared with maximal flow. The mean difference in planimetered area under different flow rates was 0.002 +/- 0.01 cm2 (p = 0.86). CONCLUSIONS: By simultaneous determination of Gorlin formula and TEE planimetry valve areas, we showed that acute changes in transvalvular volume flow substantially altered valve area calculated by the Gorlin formula but did not result in significant alterations of the anatomic valve area in aortic stenosis. These results suggest that the flow-related variation in the Gorlin AVA is due to a disproportionate flow dependence of the formula itself and not a true change in valve area.     

Paraprosthetic regurgitation in aortic prostheses: determination of the hemodynamic significance by pulsed Doppler examination of the subclavian artery flow

Paraprosthetic leaks in aortic prostheses may cause significant aortic regurgitation. Color flow Doppler echocardiography is the method of choice for detecting paraprosthetic leaks, but quantitation of regurgitation is limited by this method. This study investigated the value of pulsed Doppler of the left subclavian artery flow for assessing the hemodynamic significance of paraprosthetic regurgitation in aortic prostheses in 32 patients with, and in 77 control subjects without paraprosthetic leaks. Paraprosthetic leaks were either detected by transthoracic or transesophageal color flow echocardiography. The hemodynamic significance of paraprosthetic regurgitation was determined by means of a dichotomous angiographic classification - significant versus insignificant regurgitation. Pulsed Doppler was performed to measure the maximal diastolic and systolic velocities, and diastolic and systolic velocity-time-integrals (VTI) and their ratios in the subclavian artery flow. The accuracy of these parameters for differentiating significant versus insignificant regurgitation was assessed. Angiography revealed 13 significant and 19 insignificant forms of aortic regurgitation. In all patients, examination of the subclavian artery was feasible by pulsed Doppler. The highest correlation between Doppler derived parameters and regurgitation was calculated for the ratios of diastolic and systolic VTI (r = 0.84), diastolic VTI (r = 0.82) and ratio of diastolic and systolic velocities (r = 0.80). An increase of the ratio of diastolic and systolic VTI (> 45%) and ratio of diastolic to systolic velocity (> 0.4), and increased diastolic VTI (> 60 cm) in the subclavian artery velocity profile identified significant paraprosthetic regurgitation with a sensitivity of 94%, 75% and 87%, and specificity of 87%, 80% and 87%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

Postoperative infection following orthopaedic surgery in human immunodeficiency virus-infected hemophiliacs with CD4 counts < or = 200/mm3

Human immunodeficiency virus-infected hemophiliacs are at risk for bacterial and opportunistic infections with worsening immunosuppression. Thus, the risk of postoperative infection following orthopaedic surgery is of considerable concern. A survey of United States hemophilia treatment centers was conducted to determine the incidence of postoperative infection in human immunodeficiency virus-positive hemophiliacs with CD4 counts of 200 mm3 or less undergoing orthopaedic surgery. A total of 115 centers from 37 states reported that postoperative infection occurred in 10 (15.1%) of 66 patients undergoing 74 orthopaedic procedures, between several weeks and 5 months following surgery. In five (50%), pre-operative infection preceded postoperative joint infection. Staphylococcus was the most common organism isolated in a prosthetic joint infection, in 6 of 10 (60.0%), and the knee was the most commonly affected joint, in 9 of 10 (90.0%). Joint arthroplasty appeared to have 10 times the risk of nonarthroplasty procedures for postoperative infection (9 of 34 [26.5%] and 1 of 40 [2.5%], respectively, P < .01). Two subjects developed chronic osteomyelitis. The rate of postoperative infection in human immunodeficiency virus-positive hemophiliacs with CD4 counts of 200/mm3 or less appears to be high, when compared with the general population. Early, vigorous treatment should be instituted for suspected infection, antibiotic prophylaxis considered for invasive procedures, and surgical intervention individualized based on the balance of risks and benefits.