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AIM: To assess the accuracy of predicting intraocular lens(IOL)power after myopic refractive surgery using the Pentacam system's true net power(TNP)in the 3 mm zone combined with the SRK/T formula [i.e. TNP 3 mm(SRK/T)].METHODS: Retrospective study. This study enrolled 35 cases(50 eyes)of patients undergoing cataract surgery after laser assisted in situ keratomileusis(LASIK)or photorefractive keratectomy(PRK)from July 2019 to December 2021. Preoperatively, IOL power of 50 eyes, 34 eyes and 41 eyes was calculated by TNP 3 mm(SRK/T), Barrett True-K and Olsen 2 formulas, respectively, with at least 2 formulas used to calculate IOL power for each patient. The actual diopter was recorded 3 mo postoperatively. Prediction errors(PE)of IOL power were compared among the three calculation methods, and the proportion of eyes with PE within ±0.5 D and ±1.0 D was analyzed.RESULTS: The PE at 3 mo postoperatively for TNP 3 mm(SRK/T), Barrett True-K, and Olsen 2 was -0.02±0.63, -0.54±0.80, and 0.25±0.80 D, respectively(P<0.001). The proportions of PE within ±0.5 D were 66%(33/50), 44%(15/34)and 37%(15/41), respectively(P<0.05); the proportions of PE within ±1.0 D were 88%(44/50), 71%(24/34)and 80%(33/41), respectively(P>0.05).CONCLUSION: The Pentacam TNP 3 mm(SRK/T)method is simple to operate and provides accurate calculation of IOL power after corneal refractive surgery.
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AIM: To comparatively analyze the pain related factors levels and therapeutic response in patients treated with ~(99)Tc-MDP and ~(153)Sm-EDTMP for painful skeletal metastases. METHODS: Plasma endothelin (ET), calcitonin gene-related peptide (CGRP), thromboxane B_2 (TXB_2) and 6-keto-prostaglandin F_ 1? (6-k-PGF_ 1? ) levels were analyzed in 93 patients with painful skeletal metastases prior and 3 months after treatment. 55 cases were just treated with 153 Sm-EDTMP (group A); 19 cases were treated only with 99 Tc-MDP (group B); and 19 cases were treated with both 153 Sm-EDTMP and 99 Tc -MDP (group C). RESULTS: 69.1 %, 73.7 % and 89.5 % of the patients were experienced pain relief 3 months after treatment in groups A, B and C, respectively. Comparative analysis shows that: ET and 6-k-PGF_ 1? levels increased significantly 3 months after treatment in all patients (P
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AIM: To observe the early changes of local cerebral blood supply in dogs during the acute vertebral artery stenosis by 99 TcmECD cerebral blood flow perfusion imaging(CBFPI).METHODS: Twenty-four dogs were randomized into groups of normal controls(A),moderate stenosis(B),severe stenosis(C) and arterial occlusion(D),with 6 in each group.Group A were free from any intervention,but Group B,C and D were undergone ligation of the right vertebral arteries by the extent of 50%～69%(Group B),70%～99%(Group C) or 100%(Group D).The imaging agents were injected intravenously 0.5-1 h after ligation and the single photon emission computed tomography(SPECT) was performed after 1 h.RESULTS: CBFPI examination of the early changes of cerebral blood supply during the acute vertebral artery stenosis by visualization showed that the sensitivity was 33.3%,83.3% and 100% in Group B,C and D,respectively,with an average sensitivity of 72.2%,while semi-quantitative assessment suggested that the sensitivity was 50%,100% and 100% in the three groups,respectively,with an average sensitivity of 83.3%.When examining the activity ratio for regions of interest(ROI) by semi-quantitative 99 Tcm-ECD CBFPI,the findings suggested that Group D and C decreased significantly(exception in cerebellum in Group C),but Group B had no evident changes,as compared with Group A.By comparison of the groups of B-C,B-D and C-D,differences were observed in the right temporal lobes,whereas the changes in left temporal lobes were seen in Group B-C or B-D.The changes were seen in occipital lobes when groups of B and D were compared,but with no differences in cerebellum.CONCLUSION: The degree of stenosis in vertebral arteries may involve varied regions,the temporal lobe is susceptive,followed by occipital lobe,while cerebellum is somewhat resistant from the involvement.