Changes in optic nerve head blood flow and retrobular hemodynamics following calcium-channel blocker treatment of normal-tension glaucoma

Background: Because calcium channel blockers reduce vascularresistance, they may have a clinical application in the treatment ofnormal-tension glaucoma (NTG). This study investigates changes inboth the optic disc blood flow and the hemodynamics of retrobulbarvessels in NTG patients after the systemic administration of a calcium channel blocker. Methods: Twelve eyes of 12 NTG patients (meanage 57 6 ± 15.3 years) were examined before and after a 4-weektreatment with 2 mg b.i.d. oral nilvadipine, an L-typc calcium channel blocker. By scanning laser-Doppler flowmetry (SLDF), we obtained the velocity, flow, and volume from within a 10 × 10 pixel windowplaced on the temporal rim region of the optic disc perfusion map. Byultrasound color Doppler imaging (CDI), we measured the peak systolicvelocity (PSV) and the end diastolic velocity (EDV) of the ophthalmicartery (OA), central retinal artery (CRA), nasal posterior ciliary artery (NPCA), and temporal posterior ciliary artery (TPCA). We then calculated a resistance index (RI) for each vessel. Results: After treatment, the flow and velocity of the optic disc blood flow significantly increased (P < 0.05).Nilvadipine also significantly reduced RIs of the CRA, NPCA, and TPCA(P <0 .05), and increased both the PSV of the NPCA and the EDVs of the CRA, NPCA, and TPCA. The percent change in velocity correlated significantly with the percent changes of the CRA RI and NPCA RI. Conclusions: Oral nilvadipine appears to reduce orbital vascular resistance, which consequentlyincreases the optic disc blood flow. Abbreviations.BP – blood pressure;CRA – central retinal artery;CDI – ultrasound color Doppler imaging;EDV – end diastolic velocity;NPCA – short posterior ciliary arteries located nasal to optic nerve;NTG – normal-tension glaucoma;OA – ophthalmic artery;PP – perfusion pressure;PSV – peak systolic velocity;RI – resistance index;SLDF scanning laser-Doppler flowmetry;TPCA – short posterior ciliary arteries locatedtemporal to optic nerve.     

Breast cancer vascularity: Color Doppler sonography and histopathology study

Summary In this prospective study, the authors examined 50 patients with breast tumors (malignant, n = 32; benign, n = 18) to investigate the correlation between color Doppler flow mapping and histopathological findings and to evaluate the clinical significance of color Doppler mapping. Among the 32 patients with breast cancer, color Doppler signals were detected in 24 patients (75%). The maximum flow velocities varied from 5 to 34 cm/sec, with 16 (67%) of them above 15 cm/sec. Among the 18 patients with benign tumors, color Doppler signals could be detected in 7 (39%). The maximum flow velocity varied from 3 to 30 cm/sec but was over 15 cm/sec in only two patients (28%). Histological studies revealed that color Doppler signals detected by Doppler sonography correlated with disordered neovascularization penetrating the lesion from its periphery, consisting of thin-walled blood vessels and large arteriovenous shunts. Although large tumors tend to have high Doppler flow, there is no significant correlation between the maximum flow velocity and tumor size. There is also no significant correlation between the detection of high flow color Doppler signals and the age, receptor status, tumor size, lymph node metastases, or clinical stage of patients with breast cancer. However, there is a positive association (p < 0.05) between nodal metastases and higher tumor flow velocity in T1 ( 2 cm) breast tumors, but not in larger tumors. It is concluded that color Doppler is useful in the assessment of tumor vascularity but is of limited value in the differentiation of benign from malignant lesions. However, the presence of color Doppler signals in Tl breast cancer suggesting early dissemination of the cancer might be of important clinical significance in detecting those small, apparently early, but aggressive tumors with poor prognosis.     

Reliability of Doppler color flow mapping in the identification and localization of multiple ventricular septal defects

The purpose of this study was to compare Doppler color flow mapping with angiography and surgical observation for detection of multiple ventricular septal defects (VSDs). Only patients with elevated pulmonary ventricular pressure were included. Among 137 patients with VSDs, 38 multiple defects were identified in 25 patients echocardiographically, 34 multiple defects in 24 patients angiographically, and 21 multiple defects in 17 patients surgically. Using surgical observation as the reference standard, the sensitivity of echocardiography for identifying patients with multiple VSDs was 17 of 17 (100%) and for angiography 15 of 17 (88%). The sensitivity of echocardiography for identifying all multiple VSDs seen at operation was 19 of 21 (90%) and of angiography was also 19 of 21 (90%). In many patients, use of both techniques may no longer be necessary.     

Echocardiographic and color flow Doppler assessment of systemic and pulmonary venous connection and drainage in the neonate with congenital heart disease

Systemic and pulmonary venous anomalies are frequently encountered either as isolated lesions or as a significant component of a more complex lesion in the newborn infant with congenital heart disease. Two-dimensional echocardiography and Doppler techniques (conventional and color flow) have become the primary diagnostic imaging modality in this setting. Precise pre-operative definition of these variable venous connection and drainage patterns is critical as the required surgical procedure may solely be based on exact understanding of the veins' anatomy and physiology. On the systemic venous site, anomalies of superior and inferior venae cavae, innominate vein, and coronary sinus can be equally well imaged with either echocardiography or angiography. However, on the pulmonary venous site, echocardiography and Doppler techniques including color flow mapping are superior to angiography for precise definition of the connection and drainage sites of the individual pulmonary veins.     

In vivo structure–activity studies on the dark‐color‐inducing neurohormone of locusts

In the 11‐residue long dark‐color‐inducing neurohormone (DCIN = [His⁷]‐corazonin), of locusts, from residue 2 to residue 11, one amino acid at each time was substituted by d ‐phenylalanine (d ‐Phe). The dark‐color‐inducing effect of these peptides was investigated in comparison with unaltered DCIN by a bioassay based on nymphs of a DCIN‐deficient albino mutant of the migratory locust, Locusta migratoria. Substitution of any single amino acid by d ‐Phe always reduced the activity, but did not abolish it completely. Maximum inactivation was obtained after substitution of Gln4, Ser6, or Trp9. The latter two residues are within the partial sequence ‐Ser‐Xxx‐Gly‐Trp‐ (Xxx = His in the DCIN) that seems to be important for the dark‐color‐inducing activity, as found also in another study (Insect Biochem. Mol. Biol. 32, 2002, 909). Gln4, however, is outside of this partial sequence. Minimal, although still considerable, inactivation occurred after substitution of Gly8, Phe3, or Asn11, despite the fact that Gly8 is within the ‐Ser‐Xxx‐Gly‐Trp‐ partial sequence. In conclusion, no single active core was found, indicating that the whole sequence of the DCIN is necessary to induce maximum darkening effect. No difference was found in the activity of the peptides in which Gly8 was substituted by d ‐Phe or by L ‐Phe. Therefore the ‐Ser‐Xxx‐Gly‐Trp‐ partial sequence does not seem to be stabilized by a type II β‐turn. Nevertheless, existence of another kind of turn that includes this partial sequence is feasible. A single unsuccessful attempt was made to discover an antagonist to the DCIN.     

残根残冠修复的临床应用研究

目的 探讨残根残冠修复的临床效果。方法 对285例321颗前后牙残根残冠经过完善的根管治疗后进行铸造桩核全冠修复，并进行2年至6年的临床观察。结果 285例321颗患牙修复后成功310颗，失败11颗，成功率96．6％。结论 残根残冠经过完善的根管治疗后铸造桩核全冠修复是其目前得以保留并发挥功能的理想方法。     

钛基底对钛-瓷修复体表面色的影响

目的　探讨钛金属基底对钛 -瓷修复体表面色是否有明显影响。方法　制作 Dentsply DETREY- Carat瓷粉与钛 -瓷修复体标准试件 ,用 CS- 5型分光光度计测色 ,统计分析测定结果 ,并计算色差。结果　钛金属基底与Ni- Cr金属基底间颜色差异较大 ,但加不透明瓷及牙体瓷后 ,两组试件各色度指标统计学上无显著性差异 ,色差均小于 1.5。结论　钛金属基底对钛 -瓷修复体表面色无明显影响 ,Dentsply两种瓷粉同色瓷间无明显颜色差异。     

彩色多普勒组织显像在小儿病毒性心肌炎诊断中的应用

本文报告用彩色多普勒组织显像(DTI)测定正常小儿173名,病毒性心肌炎40例,发现DTI在正常小儿的规律。病毒性心肌炎二尖瓣环舒张早期运动速度(MVR-DeV)显著低于正常儿童,40例病毒性心肌炎MVR-DeV降低者占72.5％,经过治疗后MVR-DeV90％以上短期内恢复正常。MVR-DeV降低率显著高于心脏解剖、心功能、心脏血流参数、心电图和心肌酶的异常率。因此,MVR-DeV对病毒性心肌炎的诊断、病情了解以及疗效观察均有重要价值。     

婴幼儿先天性心脏病合并室缺的肺动脉压测定研究

目的探讨婴幼儿先天性心脏病合并室缺的肺动脉压测定与连续波多普勒法相关性的临床研究。方法40例婴幼儿先天性心脏病合并室缺患者分为两组，以室缺合并平均肺动脉压〉20mmHg为观察组，室缺合并平均肺动脉压〈20nm、Hg为对照组，应用连续波多普勒法与术前用导管法所测肺动脉压进行比较。结果观察组连续波多普勒法测出肺动脉压与导管所测肺动脉压显著相关（r=0．70，P〈0．01），可达到定量诊断肺动脉高压的目的；对照组不紧密相关（r=0．65，P〉0．05）。结论连续波多普勒法对婴幼儿先天性心脏病合并室缺的患儿的肺动脉压评估可靠。