BigSIA vs CAS_Calc

The BigSIA is an application designed, developed and sold by Manuel Rodríguez Vallejo for teaching and research purposes. Provides information to the Anterior Segment Surgeon about Corneal Induced Astigmatism (SIA) during Cataract Surgery. The application provides information to allow the surgeon to make a clinical decision based on his or her own knowledge. How to use The BigSIA? 1.- INTRODUCE SUBJECTS The first step is to introduce a subject measured during the preoperative and postoperative follow-up. The preoperative and postoperative corneal powers are the main variables although other variables can be stored for later export and analysis by other software. The subject must be entered through a unique numeric Pseudoidentifier so that no personal data is stored in the device. It is the responsibility of the user to perform an appropriate Pseudoidentification procedure. 2.- CREATE EXAMS FOR SUBJECTS AND ASSIGN A PROTOCOL TO AN EXAM Once the Subject has been introduced, an Exam should be created in the Subject screen. After creating the first Exam it will be necessary to create a new Protocol that will be assigned to that Exam. A Protocol is a uniform way of acting in such a way that the subsequent analysis is reliable. For example, a protocol could include right eyes measured with a particular instrument with a 2.2 mm temporal incision. We can assign a protocol name "protocol1" and all the subjects whose right eyes have been operated on the same incision and measured with the same instrument can be assigned to the same "protocol1". Any variation must be recorded in a different protocol, for example, if I change the eye by the left eye, I must change the protocol and it can not be assigned to "protocol1". Once the Exam is created and assigned the Protocol to it, the preoperative and postoperative corneal power data are inserted. The App will calculate the SIA for that exam. Obviously, preoperative and postoperative astigmatism must be measured through the same device. 3.- ANALYZE THE DATA After having a series of patients undergoing surgery and measured under the same protocol, we can calculate a double-angle chart with the statistics of centrality and dispersion. What are the benefits of the PRO account? The App can be downloaded for free but only 30 subjects and 1 protocol can be included. Users with the PRO annual subscription can include an unlimited number of subjects, unlimited number of protocols, import and export of data in .CSV format, export of plots in vector format, making backup copies, filter according to the magnitude of the preoperative Corneal astigmatism or filter according to the type of preoperative astigmatism (with-the-rule, against-the-rule or oblique). INFORMATION ABOUT PRO SUBSCRIPTION The BigSIA is a freemium app. If you want to access to all the services you have to buy a PRO auto-subscription for 19.99€ (prices can vary between countries) for a period of 1 year. The payment will be charged to your iTunes Account at confirmation of purchase. Subscription automatically renews unless auto-renew is turned off at least 24-hours before the end of the current period. Account will be charged for renewal within 24-hours prior to the end of the current period, and identify the cost of the renewal. Subscriptions may be managed by the user and auto-renewal may be turned off by going to the user's Account Settings after purchase. Any unused portion of a free trial period, if offered, will be forfeited when the user purchases a subscription to that publication, where applicable. You can find our terms and privacy policy at https://www.test-eye.com/index.php/en/apps-en/bigsia

CAS IOL Calc calculates the power of an intraocular lens. It is written for ophthalmic surgeons performing cataract surgery, and for anyone working with ocular biometry. FOUR ENGINES, SIDE BY SIDE • CAS Rx — the engine for routine work. Gaussian optics with a thick corneal model; the machine-learned part is the effective lens position and nothing else. Toric, suitable for all eyes. • CAS classic — the original Castrop formula with the C/H/R constant triplet. It calculates what the web version at iolcon.org calculates. • CAS AI — pure machine learning without any optical calculation, a feasibility study and a cross-check. Spherical only, with hard limits. • SRK/T — the 1990 formula, included as a yardstick because the comparison has been asked for repeatedly. We do not recommend it for clinical use. Where the four diverge, that divergence is information in itself. TWO MODES • Simple — one eye, the short form, the result directly below it. The corneal refinements sit behind a switch. • Full — both eyes in turn, with side comparison, a note field, QR import and a printable calculation sheet: one A4 page, both eyes side by side, with the inputs, the constant footing, the power table, the axis sketch, every note and the scope and limitations of the engine. FOUR MODULES The menu "Module" under the title switches between four calculation paths; the case in the main calculation stays as it is. • IOL calculation — the routine case, the lens in the capsular bag. • Add-on IOL — the supplementary lens in front of a lens already implanted, from the refraction and the pseudophakic anterior chamber depth. • IOL exchange — the replacement lens for a pseudophakic eye; the cylinder comes from the refraction, the radii run alongside as a cross-check. • Secondary implantation — the eye without capsular support, with the lens position set by hand. Each module has its own inputs, its own note field and its own printable sheet. WHAT THE APP DOES • Toric calculation with axis rose, misalignment and residual refraction • Result table with spherical equivalent and the whole lens (sph/cyl) • Refined cornea: posterior surface, thickness, tomographic cylinder • Corneal spherical aberration, derived from the radii and the asphericity (Q or e) and calibrated to the CASIA2 • Post-refractive corneas via funny cornea and the posterior radius • Read biometry from the QR code on the device printout, through the camera or from an image or PDF; the code format is documented at https://iolcon.org/download/LPCM_QR-Import.pdf • Warnings instead of silent extrapolation: percentile limits on every field, eye rarity score, side comparison of the pair, a note when keratometric and tomographic cylinder diverge • Lens catalogue with optimised constants; unknown lenses via the A constant • Full manual inside the app, in three languages • German, English, Italian PRIVACY Everything is calculated on the device. No account, no sign-in, no network connection, no data collection. There are no fields for a name or a date of birth. The report carries no patient identifier. The only things kept on the device are settings, lenses you create yourself (name and constants) and the location of the report folder – never measurements. IMPORTANT CAS IOL Calc is not a medical device. It is for investigational use. Every clinical decision remains with the treating physician. The models were trained on IOLMaster 700 measurements; for other biometers a slight loss of accuracy cannot be excluded. The limitations of each engine are shown permanently in the result panel, on the printout and in detail in the manual. The basis is the Castrop formula: Langenbucher A, Szentmáry N, Cayless A, Weisensee J, Wendelstein J, Hoffmann P. Considerations on the Castrop formula for calculation of intraocular lens power. PLoS One 2021;16(6):e0252102.