Surface location of right atrial central point by echocardiography / 中华超声影像学杂志

Objective To propose an accurate method of noninvasive determination of central venous pressure(CVP ) by locating the central point of right atrium (RA ) using echocardiography .Methods Through the 3D reconstruction ,the accurate positions of RA of 30 patients who had been examined by multislice 3‐dimensional computed tomography for chest imaging were recorded .Based on solid geometric principles ,the central point in RA was located by echocardiography and then compared with CT‐location point .The accuracy and feasibility were assessed by absolute distance (Da) ,vertical distance (Dv) and the whole time of location (T) between the two points .Results Mean Da ,Dv and T of the whole subjects were 07.6cm(95% CI:06.2to08.1cm),01.6cm(95% CI:-00.2to03.4cm),and438.0s(95% CI:400.1to 47 4.0 s) ,respectively .Conclusions The echocardiographic method on the basis of solid geometry proposed in this study could be used to locate the central point in RA accurately and simply .Thus it would be helpful to improve the accuracy of noninvasive determination of central venous pressure .

Correlation between Lens Thickness and Anterior Chamber Depth after Cataract Operation

The accuracy of intraocular lens power calculation in cataract surgery depends on three factor :accuracy of the biometric data[axial length, corneal power, predicted pseudophakic anterior chamber depth], accuracy of manufacturer of IOL power quality, and accuracy of the IOL power formulas usedto obtain desired lens power. We retrospectively analyzed 27 patients[40 eyes] who had taken 3.2 millimeterscleral tunnel incision and been implanted with Silicone IOL. We evaluated the correlation between pseudophakic anterior chamber depth and preoperative lens thickness. And, we calculated the ratio of anterior and posterior distance from the central point on the presumption that there is the central point remaining constant despite of thickening of lens. The preoperative mean lens thickness was 4.47 +/-0 .4 9 mm. The change of anterior chamber depth was significantly increased according to the lens thickness at postoperaitve 3months[r=0.57, p<0.01]. The mean ratio of anterior and posterior distance from central point was 0.29:0.71. This result suggests that the postoperative anatomical center of IOL will change more posterior as increasing preoperative lens thickness. And we concluded that we would more exactly predict postoperative pseudophakic anterior chamber depth considering the preoperative lens thickness if the ratio of lens thickening was constant.