COST Cheat Sheet 2026

The 30 highest-yield COST facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. What is the primary route by which aqueous humor drains from the eye to maintain intraocular pressure? → Schlemm's canal via the trabecular meshwork
2. What is the function of a vitrectomy in ophthalmic surgery? → To remove the vitreous humor and treat retinal conditions
3. Fuchs' endothelial corneal dystrophy primarily causes vision loss by affecting which corneal layer? → Endothelium
4. Mitomycin C is applied during trabeculectomy or pterygium excision to: → Inhibit fibroblast proliferation and scarring
5. How should a practitioner handle an unexpected finding during pharmacology basics procedures? → Document it and follow established protocols for further evaluation
6. What is the purpose of a tonometer in ophthalmic procedures? → To measure intraocular pressure.
7. A scrubbed technologist's glove is punctured during a case. Which glove technique can NOT be used to replace it? → Closed gloving
8. What is the primary purpose of aseptic technique in ophthalmic surgery? → To prevent microbial contamination and infection.
9. Which ethical principle means 'first, do no harm'? → Nonmaleficence
10. Operating on the wrong eye is classified by the National Quality Forum as a: → Never event (serious reportable event)
11. A scrub technologist gets a needlestick from a used instrument. What is the first action? → Wash the site with soap and water right away, then report the exposure
12. What does a neutral zone (hands-free technique) achieve in the ophthalmic OR? → It avoids hand-to-hand passing of sharps to reduce injuries
13. Preoperative NSAIDs (non-steroidal anti-inflammatory drops) are used before cataract surgery primarily to: → Prevent intraoperative miosis and reduce postoperative inflammation
14. Under OSHA's Bloodborne Pathogens Standard, who pays for the hepatitis B vaccine for an at-risk surgical technologist? → The employer, at no cost to the employee
15. How should a practitioner handle an unexpected finding during documentation standards procedures? → Document it and follow established protocols for further evaluation
16. In the context of Certified Ophthalmic Surgical Technologist, what is the primary goal of diagnostic procedures? → Optimal patient outcomes and safety
17. Which evidence-based approach is most important when applying patient safety protocols principles? → Integrating current research with clinical expertise and patient values
18. Which ocular tissues carry the highest risk for transmitting Creutzfeldt-Jakob disease (CJD) prions? → Retina and optic nerve
19. The aqueous humor is produced by which ocular structure? → Ciliary body
20. Which ethical principle is most directly applicable to treatment planning? → Beneficence — acting in the patient's best interest
21. Which layer of the choroid is directly adjacent to the outer surface of the retinal pigment epithelium? → Choriocapillaris
22. How should a practitioner handle an unexpected finding during clinical assessment methods procedures? → Document it and follow established protocols for further evaluation
23. Which hand hygiene method is required after caring for a patient with Clostridioides difficile? → Soap and water handwashing
24. How should a practitioner handle an unexpected finding during patient safety protocols procedures? → Document it and follow established protocols for further evaluation
25. In the context of Certified Ophthalmic Surgical Technologist, what is the primary goal of medical ethics and law? → Optimal patient outcomes and safety
26. In the context of Certified Ophthalmic Surgical Technologist, what is the primary goal of patient communication? → Optimal patient outcomes and safety
27. What role does documentation play in treatment planning? → It is a critical legal and clinical requirement
28. What is the purpose of a corneal transplant in ophthalmic surgery? → To replace a damaged cornea and restore vision
29. In a Schirmer I test, wetting of less than how many millimeters in 5 minutes generally suggests aqueous tear deficiency? → 5 mm
30. How should the circulator pour sterile balanced salt solution into a basin on the sterile field? → Pour slowly from high enough to avoid splashing, without touching the basin