J Refract Surg. 2024 Apr;40(4):e260-e269. doi: 10.3928/1081597X-20240311-07. Epub 2024 Apr 1.
To compare the parameters of three different topographic devices (Pentacam HR, Oculus Optikgeräte GmbH; Sirius, Costruzione Strumenti Oftalmici; and Cassini, i-Optics) in grading the severity of keratoconus in cross-linked and non-cross-linked eyes.
This was a prospective comparative interventional study done in a tertiary eye care center, wherein 114 eyes of 68 patients with keratoconus were divided into two groups: 62 eyes that were observed and 52 eyes that were cross-linked. All eyes were evaluated on all three topographers at baseline, 3-month follow-up, and 6-month follow-up.
The Sirius showed significantly lower values of mean flat keratometry in comparison to the Pentacam HR (limits of agreement [LoA]: 1.75 to 3.51%) and Cassini (LoA: 1.75 to 3.51%). The mean steep keratometry values were higher for the Cassini in comparison to the Pentacam HR (LoA: 4.39 to 7.02%) and Sirius (LoA: 3.51 to 6.14%). The mean steep keratometry values of the Sirius were significantly lower than those of the Pentacam HR and in both the cross-linked and observation groups (LoA: 3.51 to 6.14%). The mean keratometry values were significantly higher in the Cassini compared to the Pentacam HR (LoA: 3.51 to 8.77%) and significantly lower in the Sirius in comparison to the Pentacam HR (LoA: 3.51 to 6.14%). The mean difference in astigmatism was also statistically significant between the three tomographers in both groups, with the Cassini showing higher values (LoA: 3.51 to 5.26%) and the Sirius lower values than the Pentacam HR (LoA: 5.26 to 6.14%).
The authors conclude the three devices cannot be used interchangeably. The Cassini showed better agreement and correlation with the Pentacam HR in the staging of keratoconus, whereas the Sirius tended to underdiagnose and under-stage the disease. .
比较三种不同地形图仪（Pentacam HR、Oculus Optikgeräte GmbH；Sirius、Costruzione Strumenti Oftalmici；以及 Cassini、i-Optics）在交联和未交联眼评估圆锥角膜严重程度的参数。
这是一项在三级眼科中心进行的前瞻性对比干预研究，纳入 68 例圆锥角膜患者的 114 只眼，分为观察组（62 只眼）和交联组（52 只眼）。所有眼均在基线、3 个月随访和 6 个月随访时用 3 种地形图仪进行评估。
与 Pentacam HR（容许区间 [LoA]：1.75 至 3.51%）和 Cassini（LoA：1.75 至 3.51%）相比，Sirius 的平均平 K 值明显较低。Cassini 的平均陡 K 值明显高于 Pentacam HR（LoA：4.39 至 7.02%）和 Sirius（LoA：3.51 至 6.14%）。与 Pentacam HR 和交联组及观察组相比，Sirius 的平均陡 K 值明显更低（LoA：3.51 至 6.14%）。Cassini 的平均 K 值明显高于 Pentacam HR（LoA：3.51 至 8.77%），而 Sirius 的平均 K 值明显低于 Pentacam HR（LoA：3.51 至 6.14%）。两组中三种断层扫描仪之间的平均散光差异也具有统计学意义，Cassini 显示出更高的值（LoA：3.51 至 5.26%），而 Sirius 则低于 Pentacam HR（LoA：5.26 至 6.14%）。
作者得出结论，这三种设备不能互换使用。与 Pentacam HR 相比，Cassini 在圆锥角膜分期中具有更好的一致性和相关性，而 Sirius 倾向于低估和低估疾病。
