Most of what you will read while shopping for an OCT is written by the people who build them. This OCT machine buying guide is written from the other side of the purchase order — the procurement side. It assumes you already know what an OCT does in your lane, and that what you actually need help with is narrower: which differences between systems will change your day-to-day, which are marketing, and what you are committing to for the next seven to ten years once the unit is bolted to a table.
An OCT is rarely a one-time purchase. It is a platform decision. The device arrives with a software ecosystem, a data format, a service relationship, and an upgrade path attached, and those outlast the hardware. Here is how to evaluate all of it before you sign.
Start with the scans you will actually run
Before comparing any two systems, write down the scan protocols your practice will run in a normal week and roughly how often. Posterior segment work, glaucoma follow-up, anterior segment imaging, and angiography are different asks of the same box, and the configuration you need follows directly from that list. A practice running high-volume follow-up has a different problem than one doing occasional referral-grade imaging — the first is buying throughput and repeatability, the second is buying capability.
This list is also your negotiating instrument. Vendors quote configurations, not devices. Knowing which modules you will use in year one — and which you would only use if a subspecialty joins later — is what separates a right-sized quote from an expensive one.
Spectral-domain vs. swept-source: what the difference actually buys you
This is the comparison that dominates the category, and it is worth being precise about it rather than treating "newer" as "better."
Scan speed
Speed is measured in axial scans (A-scans) per second. Review of Optometry puts current spectral-domain models at 26,000 to 80,000 axial scans per second, and swept-source systems at 100,000 to 200,000. In the room, that number translates into acquisition time — how long a patient has to hold steady, and how many usable captures you get per attempt with a difficult fixator. It is one of the few specs that reliably shows up in your schedule.
Depth and the choroid
Swept-source systems image deeper, which is the standard argument for the tier. But the gap is not absolute: Eyes On Eyecare notes that enhanced depth imaging (EDI) on spectral-domain devices can partially mitigate the difference in choroidal visualization, and that the practical clinical benefits of swept-source versus spectral-domain "remain to be strongly validated." If a vendor is selling you the depth argument, ask whether EDI is included on the spectral-domain unit you are comparing against — it is often an option worth asking for by name.
Angiography
OCT angiography is now available on both technologies, so it is no longer a reason on its own to move tiers. Treat OCT-A as a line item: decide from your scan list whether you will use it, price it as a module, and ask whether it can be added later or must be specified at purchase.
The software is the product
The single most common procurement mistake in this category is evaluating the hardware and inheriting the software. Three things deserve direct questions:
- The normative database. Eyes On Eyecare is blunt about the consequence: RNFL thickness values "are not interchangeable between the devices," because devices use different normative data and signal strengths. That is a purchasing fact, not a clinical footnote — it means your accumulated baselines do not port cleanly if you switch platforms. Ask what happens to your existing data, and whether the vendor supports importing it.
- Licensing and upgrades. Ask which analysis modules are licensed separately, what a software upgrade costs after the warranty period, and whether upgrades are included in a service agreement or billed per release.
- Viewing stations. Ask how many concurrent viewing seats are included and what each additional one costs. A device that can only be reviewed at the device is a workflow problem you will discover in month two.
Integration: where your images actually live
Ophthalmic imaging has a long history of proprietary silos. As Medicai describes it, each imaging device historically shipped with its own software writing to its own format — Zeiss Forum for Cirrus data, Heidelberg HEYEX for Spectralis, Topcon IMAGEnet for Triton. The practical fix is DICOM compliance, which lets a vendor-neutral archive ingest data from any DICOM-compliant device regardless of manufacturer and normalize it into one archive with a single viewer.
Two questions get you most of the way there:
- Does it support DICOM modality worklist? Modality worklist carries the scheduled imaging context from the EHR to the device, so a scheduled exam appears on the OCT when the technician pulls up the patient, instead of being typed in by hand. Manual entry is where mismatched patient records come from.
- How does it talk to your EHR? Integration typically runs over HL7 v2 messaging for demographics and orders, or increasingly FHIR APIs in cloud-native deployments. Ask your EHR vendor and your OCT vendor the same question separately, and compare the answers before you buy — not after.
Get any integration promise in writing, in the quote. "It integrates" is not a specification.
Fit the room, not just the budget
Footprint, table requirements, and power are the boring constraints that derail installs. Measure the room the unit is going into, including the door it has to come through and the clearance a technician needs to work behind the patient. Confirm whether the quoted table is included or assumed, and whether the device needs a dedicated circuit. If you are equipping from scratch rather than replacing, our equipment checklist for opening a new practice sequences the room build so imaging lands after the lane is actually ready for it.
Total cost of ownership beyond the purchase order
The quoted number is the beginning of the cost, not the whole of it. Build your comparison across at least five years and include: the service agreement after the warranty lapses; software upgrades and module licenses; additional viewing seats; installation and calibration; staff training, including retraining when the technician who ran it leaves; and the cost of downtime, which is the one nobody quotes and everybody eventually pays.
Review of Optometry lists warranty length, software upgrade expense, service agreements, and whether training is included in the purchase price among the cost factors buyers should be evaluating — and flags inadequate staff training as a recurring misstep. That last point is worth taking seriously: a capable device that only one person can operate well is a partially purchased device.
Service, warranty, and uptime
This is where an equipment provider earns its keep, and where the shortlist usually resolves. Ask who performs the service — the seller or a subcontractor — and where the parts are. Ask the realistic response time for your zip code, whether loaner equipment exists during a repair, and what the warranty actually covers versus excludes. A device that is down for three weeks because a part is crossing an ocean is not a bargain at any price.
US Ophthalmic is not a middleman on this: we run an in-house technical and spare-parts department and support what we sell, which is the entire reason the warranty conversation is worth having with us directly. Our customer service and support page covers how service requests actually route, and why practices choose US Ophthalmic lays out what we stand behind.
New, open-box, or pre-owned
OCT is one of the categories where the pre-owned decision needs the most care, precisely because of the software and normative-database questions above. A well-inspected unit from a seller who can service it is a legitimate way into the category; an auction-lot unit with no software entitlement and no service path is a liability. If you are weighing it, our guide to buying used ophthalmic equipment lays out the inspection and warranty questions in full, and current open-box and clearance inventory is worth checking before you commit to new — availability changes constantly.
The one rule specific to OCT: confirm in writing that the software license and any analysis modules transfer with the unit, and that the seller can still obtain parts and service for that model. Do not assume either.
The vendor questionnaire
Send the same list to every vendor on your shortlist and compare the answers side by side. The answers, and how readily they come, tell you as much as the specs:
- What is the A-scan rate, and what is the realistic acquisition time for the protocols on my list?
- Is EDI included or optional on this configuration?
- Which analysis modules are licensed separately, and what do they cost to add later?
- Does the system export DICOM, and does it support modality worklist?
- Has this model been integrated with my specific EHR before? With whom can I speak?
- Can my existing imaging data be imported, and what is lost if it is not?
- What does the warranty cover, for how long, and what does it exclude?
- Who performs service, where are the parts, and what is the response time to my location?
- What training is included, and what does retraining a new technician cost?
- What has the software upgrade cadence and cost been over the past five years?
Frequently asked questions
Is swept-source OCT worth it over spectral-domain?
It depends on your scan list, not on the tier name. Swept-source runs faster — 100,000 to 200,000 A-scans per second versus 26,000 to 80,000 for current spectral-domain models, per Review of Optometry — and images deeper. But Eyes On Eyecare notes the practical clinical benefits of swept-source over spectral-domain remain to be strongly validated, and that EDI on a spectral-domain device can partially close the choroidal-visualization gap. Compare a specific configuration against a specific configuration, not a category against a category.
Can I move my existing OCT data to a new device?
Not automatically, and this is the question buyers most often ask too late. Devices use different normative data and signal strengths, and RNFL thickness values are not interchangeable between them. Ask each vendor directly what import path exists and what your baselines are worth on the new platform before you switch.
Do I need OCT angiography?
OCT-A is available on both spectral-domain and swept-source systems, so it is a module decision rather than a tier decision. Work it out from the scan list you wrote down first, and ask whether it can be added later or has to be specified at purchase.
What does DICOM support mean in practice?
It means your images are not trapped in one vendor's software. A DICOM-compliant device can feed a vendor-neutral archive alongside equipment from other manufacturers and be reviewed through one viewer. It also enables modality worklist, which pushes the scheduled exam from your EHR to the device instead of relying on manual entry.
Should I buy a refurbished OCT?
It can be a sound way into the category if — and only if — the unit comes from a seller who can service it, the software license and modules transfer with it, and parts are still available for the model. Get all three in writing. Our used-equipment guide covers the full inspection checklist.
Talk it through with someone who services the equipment
If you want the shortlist narrowed against your actual scan list, room, and EHR rather than against a spec sheet, that is a conversation worth having before you shop. You can see the OCT systems we carry, compare them against the retinal cameras that may cover part of the same need, and read our clinical overview of retinal imaging in eye care for the imaging context behind the purchase.
When you are ready for real numbers, configurations, and availability: Request a Quote — we will come back with a configuration built around your scan list, not a catalog page. Financing options are available.
Sources consulted: Review of Optometry, "Conquer These OCT Technology Choices and Challenges"; Eyes On Eyecare, "What's the Right OCT for You?"; Medicai, "Ophthalmology PACS".