OCT-C study guide
OCT-C · Work through your exam, one topic at a time.
The OCT-C (Certified Optical Coherence Tomography Technologist) credential, administered by the Ophthalmic Photographers' Society, recognizes technologists who can independently acquire, evaluate, and troubleshoot OCT images across posterior and anterior segment applications. It is aimed at ophthalmic photographers, imaging technicians, and ophthalmic assistants whose daily work includes OCT capture and image review, and who want a formal demonstration of competence beyond on-the-job training. The OCT-C study guide has 7 sections and about 2,546 words.
01Fundamentals of OCT: Physics, Light Sources, Interferometry, Scan Types and Instrumentation
OCT is the optical analogue of ultrasound: it measures the echo delay of near-infrared light using low-coherence interferometry . Light is split into a sample arm (eye) and a reference arm (mirror or fixed path).
394 words, about 2 min02Normal Anatomy on OCT: Retinal Layers, Vitreoretinal Interface, Choroid and Optic Nerve Head
On a normal macular B-scan the bands run: ILM (hyperreflective, first interface with vitreous), RNFL , GCL , IPL (hyperreflective), INL (hyporeflective), OPL (hyperreflective, contains Henle fibre layer temporally), ONL (hyporeflective), then the four outer bands - ELM , ellipsoid zone (EZ, formerly IS/OS junction) , interdigitation zone (IZ) , and the RPE/Bruch membrane complex . The EZ is the single most clinically weighted band: its continuity tracks photoreceptor integrity.
378 words, about 2 min03Image Acquisition: Scan Protocols, Centration, Alignment and Instrument Operation
Match the protocol to the question. A macular volume/raster (e.g.
384 words, about 2 min04Image Quality Assessment, Artifacts and Troubleshooting
Assess four things in order: signal strength , centration , motion/blink integrity , and segmentation correctness . A scan that fails any of these cannot support a diagnosis of thinning, oedema or progression.
348 words, about 2 min05Recognition of Retinal, Vitreous and Choroidal Pathology on OCT
Ask where the abnormality sits relative to the RPE - this single question resolves most questions. Intraretinal: cystoid spaces (macular oedema from any cause), intraretinal fluid, hard exudates (hyperreflective with shadowing), cotton-wool spots, intraretinal haemorrhage.
351 words, about 2 min06Anterior Segment and Corneal OCT Applications
Anterior segment OCT must penetrate the opaque sclera and the tear film/air interface. The usual wavelength is ~1310 nm , which scatters less in sclera and gives better depth penetration than the 840 nm used for retina; the trade-off is slightly lower axial resolution.
340 words, about 2 min07Patient Safety, Infection Control and Professional Practice Standards
OCT uses low-power, non-ionising near-infrared light; there is no ionising radiation and no magnetic field, so pregnancy and implanted electronic devices are not contraindications in themselves. Output at the cornea is typically well under a milliwatt and within the applicable laser safety standard (ANSI Z136 series and local equivalents), making clinical OCT instruments Class 1 devices in normal use.
351 words, about 2 min