Research progress on prediction of postoperative intraocular lens position.

With the progress in refractive cataract surgery, more intraocular lens (IOL) power formulas have been introduced with the aim of reducing the postoperative refractive error. The postoperative IOL position is critical to IOL power calculations. Therefore, the improvements in postoperative IOL position prediction will enable better selection of IOL power and postoperative refraction. In the past, the postoperative IOL position was mainly predicted by preoperative anterior segment parameters such as preoperative axial length (AL), anterior chamber depth (ACD), and corneal curvature. In recent years, some novel methods including the intraoperative ACD, crystalline lens geometry, and artificial intelligence (AI) of prediction of postoperative IOL position have been reported. This article attempts to give a review about the research progress on prediction of the postoperative IOL position.

Preliminary clinical report of alternate episodes of Posner-Schlossman syndrome and viral keratitis.

Posner-Schlossman syndrome (PSS) and viral keratitis have a shared pathogen and are common diseases in China, but there are few case reports on whether these two diseases occur concurrently or alternately. After long-term clinical observations, six patients with alternating episodes of PSS and viral keratitis were confirmed at our hospital in the past 10 years. Of the six patients, three were female and three were male. Four patients had monocular PSS with ipsilateral monocular viral keratitis, one had monocular PSS with bilateral viral keratitis, and one had bilateral PSS with bilateral viral keratitis. Of the six cases, three had epithelial viral keratitis and three had endothelial viral keratitis. In four cases, the interval between the onset of the two diseases ranged from 8 days to 3 years, and two cases showed overlapping manifestations of the two diseases in 3 to 6 days, both with incomplete absorption of keratic precipitates. The six cases had intermittent episodes of both diseases and significant loss of corneal sensation during the onset of viral keratitis, and were effectively treated with antiviral therapy. PSS and viral keratitis may alternate episodically, and clinical attention should be paid to these conditions. The mechanism of the alternate episodes might be associated with viral infection and the use of glucocorticoids.

Time-course changes in left ventricular myocardial deformation in STZ-induced rabbits on velocity vector imaging.

OBJECTIVES: To clarify the time-course changes in left ventricular myocardial deformation using velocity vector imaging and to provide insights into our understanding of the cardiac pathophysiology in diabetes mellitus. METHODS: Thirty New Zealand white rabbits were randomly divided into either the control group (n = 10) or the diabetes mellitus (DM) group (induced with STZ, n = 20). For the myocardial deformation studies, echocardiography and syngo-vector velocity imaging (VVI) were performed at baseline and after 2, 4, 8, and 12 weeks in all of the rabbits. The left ventricular (LV) global longitudinal and circumferential strain and strain rate were measured. For histomorphological study of the heart structure, 2 of the STZ-induced rabbits were killed at 2, 4, 8, and 12 weeks. Routine hematoxylin and eosin staining was performed. RESULTS: At 2 weeks, the global longitudinal strain (GLS), systolic strain rate (GLSRs), and diastolic strain rate (GLSRd) were significantly lower in the DM group compared with the control group (-18.16% versus -24.00%, -1.86 s(-1) versus -2.49 s(-1), 1.93 s(-1) versus 2.42 s(-1), respectively, P < 0.05), while, compared with the control group, the global circumferential strain (GCS), systolic strain rate (GCSRs), and diastolic strain rate (GCSRd) in the DM group were significantly decreased (-12.77% versus -23.31%, -1.31 s(-1) versus -2.20 s(-1), 1.41 s(-1) versus 2.15 s(-1), respectively, P < 0.05) at 8 weeks. With the progression of untreated diabetes, the histoanatomical alterations intensified gradually beginning at 2 weeks. CONCLUSIONS: The progressive impairments in LV myocardial deformation and structure occurred early in diabetic rabbits with normal LV ejection fraction (EF), FS, and E/A. VVI could be used to evaluate subtle cardiac dysfunction in the early phase of DM.

Assessment of regional myocardial function in patients with dilated cardiomyopathy by velocity vector imaging.

OBJECTIVE: To assess the left ventricular (LV) longitudinal systolic and diastolic function in patients with dilated cardiomyopathy (DCM) by syngo Velocity Vector Imaging (VVI). METHODS: Digital dynamic images of 30 DCM patients and 30 healthy subjects were collected; then the longitudinal velocity, strain, and strain rate were measured in systolic early and late diastolic periods, and the time to peak systolic velocity, strain, and strain rate were measured and recorded. The parameters of the two groups were compared. RESULTS: All of the parameters of the DCM were significantly lower than those of the normal group (P < 0.05-0.01), except that the parameter of late diastolic strain was not different between the two groups (P > 0.05). CONCLUSIONS: VVI is a novel noninvasive tool to assess quantitatively and objectively LV regional systolic and diastolic function in patients with DCM; it provides another useful modality for evaluating cardiac function.