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OBJECTIVES: The purpose of this study was to assess the impact of pre-intervention arterial remodeling on subsequent vessel behavior following balloon angioplasty. BACKGROUND: Positive arterial remodeling before intervention has been shown to have a negative impact on the clinical outcome after nonstented coronary interventional procedures. However, the mechanism of interventions in coronary vessel geometry over time is less well characterized. METHODS: Serial (pre-, post- and follow-up) intravascular ultrasound analysis was performed in 46 native coronary lesions. Positive remodeling (PR) was defined as vessel area (VA) at the target lesion greater than that of average reference segments. Intermediate or negative remodeling (IR/NR) was defined as VA at the target lesion less than or equal to that of average reference segment. Remodeling index was defined as VA at the target lesion site divided by that of average references. RESULTS: Pre-interventional PR and IR/NR were present in 21 (46%) and 25 (54%) of 46 patients, respectively. At follow-up, the change in plaque area was similar between the two groups (1.3 +/- 2.1 vs. 1.2 +/- 2.1 mm(2), p = 0.840). Lesions with PR showed a significantly smaller change in VA than those with IR/NR (-0.2 +/- 2.5 vs. 1.4 +/- 2.3 mm(2), p = 0.03). As a result, late lumen loss was significantly larger in lesions whose pre-intervention configuration exhibited PR (-1.5 +/- 1.8 vs. 0.2 +/- 1.6 mm(2), p = 0.002). CONCLUSIONS: Lesions with PR appear to have less capacity to compensate for further plaque growth after balloon angioplasty and thus show a proportional increase in late lumen loss. This may in part explain the less favorable clinical outcomes of positively remodeled lesions.

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With the advent of intravascular brachytherapy (IVBT), a striking reduction in the rate of restenosis has been observed. The use of intravascular ultrasound (IVUS) during IVBT trials has shown many aspects and relevant pathophysiologic mechanisms following this practical therapy. Specifically, IVUS quantitative assessments have demonstrated a drastic inhibition of both neointimal formation and negative remodeling to be the predominant vascular response to IVBT. Moreover, IVBT has shown promise for challenging high-risk restenosis cases, such as patients with diabetes mellitus and smaller caliber target vessels. However, unexpected radiation-induced complications have also been discovered, as more patients have been treated for a broad class of lesion subsets. Edge effect, induced by catheter-based radiation, was seen to be due to geographic miss of the radiation source, advocating a new concept known as "radiation edge". Furthermore, late thrombosis, which is known to be strongly associated with new stent implantation following IVBT, may be avoided with novel antiplatelet agents. Two additional complications, whose clinical significance remains unclear, are unhealed dissection and late stent malapposition featured by IVUS qualitative assessment. Unhealed dissection was observed in half of radiated dissections and late stent malapposition has been seen for all radiation sources in a small percentage of cases at 6-12 months follow-up. Radiation sources, dosimetry, and delivery methods continue to improve and should ultimately translate to more effective treatment for the patient with atherosclerotic coronary disease.

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BACKGROUND: Vessel remodeling is an important mechanism of late lumen loss after nonstent coronary interventions. However, its impact on in-stent restenosis has not been systematically investigated. METHODS AND RESULTS: Serial volumetric intravascular ultrasound analyses (poststent and follow-up) were performed in 55 lesions treated with a balloon-expandable stent (ACS MultiLink) using standard stent deployment techniques. The vessel volume (VV), lumen volume (LV), and volume bordered by the stent (SV) were measured using Simpson's method. The volume of plaque and neointima outside the stent (peri-stent volume, PSV) and volume of neointima within the stent (intrastent volume) were also measured. The change of each parameter during the follow-up period (follow-up minus poststent) was calculated and then divided by SV to normalize these values (designated as percent change [%]). As expected, %PSV directly correlated with %VV (P<0.0001, r=0.935), with no significant SV. A highly significant inverse correlation was seen between %PSV and the percent change of intrastent volume (P<0.0001, r=0.517). Consequently, %LV significantly correlated with peri-stent remodeling, as measured by %VV (P<0.0001, r=0.602). CONCLUSION: Positive remodeling of the vessel exterior to a coronary stent occurs to a variable degree after stent implantation. There is a distinct trade-off between positive remodeling and in-stent hyperplasia: in segments in which the degree of peri-stent remodeling is less, intrastent neointimal proliferation is greater and accompanied by more significant late lumen loss.

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OBJECTIVES: The study was done to elucidate the relationship between baseline arterial remodeling and clinical outcome following stenting. BACKGROUND: The impact of preintervention arterial remodeling on subsequent vessel response and clinical outcome has been reported following nonstent coronary interventions. However, in stented segments, the impact of preintervention remodeling on clinical outcome has not been clarified. METHODS: Preintervention remodeling was assessed in 108 native coronary lesions by using intravascular ultrasound (IVUS). Positive remodeling (PR) was defined as vessel area (VA) at the target lesion greater than that of average reference segments. Intermediate or negative remodeling (IR/NR) was defined as VA at the target lesion less than or equal to that of average reference segment. Remodeling index expressed as a continuous variable was defined as VA at the target lesion site divided by that of average reference segments. RESULTS: Positive remodeling was present in 59 (55%) and IR/NR in 49 (45%) lesions. Although final minimal stent areas were similar (7.76 +/- 1.80 vs. 8.09 +/- 1.90 mm2, p = 0.36), target vessel revascularization (TVR) rate at nine-month follow-up was significantly higher in the PR group (22.0% vs. 4.1%, p = 0.01). By multivariate logistic regression analysis, higher remodeling index was the only independent predictor of TVR (p = 0.02). CONCLUSIONS: Lesions with PR before intervention appear to have a worse clinical outcome following IVUS-guided stenting. Intravascular ultrasound imaging before stenting may be helpful to stratify lesions at high risk for accelerated intimal proliferation.

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The purpose of this study was to clarify the 3-dimensional behavior of plaque during coronary stent expansion. Serial intravascular ultrasound (IVUS) studies, preintervention, and poststenting were evaluated in 32 patients treated with a single-balloon expandable tubular stent. External elastic membrane (EEM), lumen, stent, and plaque + media cross-sectional area were measured at 1-mm intervals through the entire stent as well as proximal and distal reference segments 5 mm from the stent edge. Volumetric calculations were based on Simpson's rule. Overall, the plaque + media volume through the entire lesion did not change during stent expansion (218 +/- 51 vs 217 +/- 47 mm3, p = 0.69). However, EEM and lumen volume increased significantly (EEM volume, 391 +/- 84 vs 448 +/- 87 mm3 [p < 0.0001]; lumen volume, 173 +/- 52 vs 231 +/- 54 mm3 [p < 0.0001]). The change in lumen volume correlated strongly with the change in EEM volume (r = 0.85, p < 0.0001), but poorly with the change in plaque + media volume (r = 0.37, p = 0.03). Plaque + media volume decreased in the midstent zone (59 +/- 14 vs 53 +/- 11 mm3, p = 0.0005), and increased in the distal stent zone (40 +/- 11 vs 44 +/- 9 mm3, p = 0.003), but did not change in either the proximal stent zone or reference segments. The mechanism of stent expansion is a combination of vessel stretch and plaque redistribution, translating disease accumulation from the midstent zone to the distal stent zone.

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BACKGROUND: Ultra-high-frequency (40- to 50-MHz) intravascular ultrasound (IVUS) improves image quality compared with conventional 20- to 30-MHz IVUS. However, as the frequency of IVUS increases, high-intensity backscatter from blood components may cause visual difficulties in discrimination between the lumen and arterial wall structure. The purpose of this study was to evaluate the effect of a novel blood noise reduction algorithm (BNR) on quantitative coronary ultrasound measurements. METHODS AND RESULTS: IVUS studies using a 40-MHz transducer were performed in 35 patients with coronary artery disease. A total of 620 gray-scale images (310 pairs) were processed with and without the BNR, and lumen cross-sectional area (CSA) was determined by 2 independent observers. With the BNR, the intraobserver and interobserver correlation coefficients for lumen CSA were significantly improved (0.85 to 0.99 and 0.80 to 0.98, respectively). In the 270 images (135 pairs) in which vessel wall measurements were possible, the BNR significantly improved the intraobserver and interobserver correlation coefficients for plaque plus media CSA (0.83 to 0.99 and 0.76 to 0.97, respectively), whereas no influence was observed for external elastic membrane CSA (1.00 to 1.00 and 0.99 to 0.99, respectively). CONCLUSIONS: This study demonstrates the feasibility of this novel algorithm to reduce blood noise, thereby enabling accurate lumen border delineation and providing reproducible measurements of both the lumen and plaque plus media CSAs. Incorporating a digital BNR may serve as an important adjunct to ultra-high-frequency IVUS imaging for improving accurate quantitative evaluation of vessel dimensions.

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Automated edge detection may standardize measurements among observers, providing for rapid assessment of intravascular ultrasound (IVUS) images. However, with high frequency images, enhanced blood signals make it difficult to define and trace the lumen borders. Accordingly, we evaluated a fully automated contour analysis facilitated with a blood noise reduction algorithm (BNR) for 40-MHz IVUS images in human coronary arteries of 27 patients. This algorithm is based on the principle that blood echo speckles have higher temporal and spatial variations than the arterial wall. A total of 193 paired lumen areas and 78 external elastic membrane (EEM) areas were measured and compared. Automated measurements showed good agreement with manual tracings for lumen and EEM area, with high correlation coefficients (0.945 and 0.950, respectively) and small variability (0.4 +/- 14.4% and 0.6 +/- 9.7%, respectively). This preliminary finding suggests that automated contour detection facilitated with BNR appeared to be a feasible and reliable technique for area measurements in 40-MHz IVUS imaging.

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After illustrating the main difficulties usually encountered in efforts to prevent injuries and improve the safety of populations, this paper will propose a frame of reference on the subject of safety promotion. It applies to the prevention of non-intentional injuries as well as to the problem of violent crimes and suicide. This framework should facilitate dialogue among those involved in these issues by encouraging better integration of the various prevention models used. It should also improve both the implementation and effectiveness of interdisciplinary and intersectorial interventions.

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In the light of two cases of benign schwannomas of the tongue, including one particularly large tumour, the authors review the clinical and histological features and natural history of these tumours. Their rarity may explain the limited knowledge concerning these tumours and the long interval prior to treatment, resulting in technical difficulties due to their volume. Surgical enucleation is generally easy to perform. The prognosis is excellent after resection, as malignant transformation is exceptional.

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A histological study of the margins of radical prostatectomy specimens has been made intraoperatively by frozen section in a series of 66 patients. In 8 of them (12% of all) a positive margin was discovered 10 times at the urethral [3], vesical [2], deferential [1] level, at the level of the Santorini [1] and of the rectoprostatic wall [3]. Further resection was immediately performed until histologically normal tissue was reached in 6 of these patients, for whom positive margins were thus made negative; and the prostatectomy was performed. The prostate was not removed in two patients. Only one positive margin not screened intraoperatively was discovered on definitive specimen examination. The rate of postoperative PSA was lowered in the 6 patients whose margins had been made negative, which is compatible with complete resection. However, 7 of these 8 patients received radiation (45 gray). We made a comparison between the groups with negative (57 patients) and positive margins (9 patients) for preoperative PSA levels, Gleason's scores, and invasion of the capsule, of the seminal vesicles and of the lymph nodes. There was no significant difference between both groups for the PSA levels, Gleason's score and the involvement of the seminal vesicles. Conversely, there was a significant difference between both groups (corrected chi 2 test) for invasion of the capsule (p = 0.02) and of lymph nodes (p = 0.02). Intraoperative histological control allows immediately recognizing and treating some positive margins, in order to choose during the operation whether resection should be widened or abandoned.

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Ultrasonically guided liver puncture was carried out in 26 patients without overt carcinoma, who presented with a small intrahepatic mass giving an ultrasonographic image of primary or secondary tumour. Puncture was performed with a lumbar or a Chiba needle under local anaesthesia, and a real-time ultrasound apparatus with guide was used. The specimens collected were fixed on slides for histological examination. An aetiological diagnosis was made in 73% of the cases (16 carcinomas and 3 liver abscesses). No abnormal cells were detected and further investigations were conducted in 15%. The failure rate was 12% (2 punctures without specimens and 1 false-negative result). No infectious or haemorrhagic complication was observed.

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In anticipation of the use of functional T-lymphocyte hybrids in adoptive immunotherapy, the differentiation and tumorigenicity of hybrid clones generated by fusion of a T lymphocyte derived from F1 (DBA/J2 x AKR) mouse spleen, and a polyoma virus-transformed fibroblast initiated from C3H mouse cells, were studied. The hybrid cells grew in suspension and had an appearance (by transmission and scanning electron microscopy) very similar to that of the lymphocytic line. The hybrid and the different clones could induce tumour grafts. Malignancy was dominant in newborn mice where tumours were obtained in all mouse strains (allogeneic or semi-allogeneic) inoculated. In adult mice, the hybrid cells were tumorigenic in C3H and F1 (DBA/J2 x AKR), whereas there was complete tumour rejection in allogeneic (C57/BL6) or semi-allogeneic (DBA/J2 and AKR) mice. The role played by major histocompatibility antigens in the graft rejection is discussed. The histology of the tumour grafts was intermediate between fibrosarcoma and lymphosarcoma.

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