Per-Modality Profitability: MRI vs CT vs Ultrasound vs PET

A four-center imaging group in SE Florida posted $11.8M of revenue and $1.94M of EBITDA last year. On paper, a 16.4% margin. The CFO was satisfied. The lender was satisfied. The owner was not — because the cash story told a different version, and nobody could explain why.

Once we decomposed the P&L by modality, the picture flipped. Three of the four modalities were running clean, double-digit contribution margins. The fourth — the one the owner had been pushing the hardest, the one the marketing team was bragging about, the one that had grown 31% year-over-year — was running structurally negative on a per-claim basis once tracer-input costs and prior-auth labor were properly allocated.

The 16.4% headline EBITDA was three healthy businesses subsidizing one money-losing one. Nobody had said it out loud because nobody had built the report.

This article is the per-modality profitability framework we apply inside every Strategic Radiology Review. It turns "imaging revenue" into four discrete businesses with four discrete economics — and exposes which modalities are paying the bills versus which are quietly burning the cash.

Key Takeaway: Imaging centers do not have a single business — they have four. MRI, CT, ultrasound, and PET Tracer Scans each have fundamentally different per-claim revenue, cost structure, payer-mix exposure, and DSO. Rolling them into a single "imaging" line on the P&L produces a number that is mathematically valid and operationally meaningless. The right framework is per-modality contribution margin: $/claim → variable cost → contribution $ → contribution %. Most multi-center SE Florida operators have at least one modality running 30+ percentage points below the others — and have never seen it on a financial report.

Why the Single-Line P&L Is Killing Your Decisions

Most imaging-center P&Ls are built for tax compliance, not management. They report:

This format passes IRS scrutiny. It says nothing about which modality is making money.

Owners running this format end up making capacity, marketing, and capital-allocation decisions based on volume signals rather than profitability signals. They see MRI volume up 18%, conclude MRI is performing, and approve a second magnet. Six months later they wonder why cash got worse, not better.

The fix is structurally simple and operationally rare: rebuild the P&L with modality as the primary segmentation axis. Every dollar of revenue gets tagged to a modality. Every variable cost gets traced. Fixed costs get allocated by use, not by square footage. The output is four (or five) parallel mini-P&Ls instead of one unified one.

The Four-Modality Framework

For SE Florida multi-center imaging, the natural segmentation:

  1. MRI — high-revenue per claim, capital-intensive, payer-mix-exposed
  2. CT — moderate revenue, throughput business, Medicare-heavy
  3. Ultrasound (with X-ray and DEXA grouped) — low revenue per claim, high volume, fast cash conversion
  4. PET Tracer Scans — high revenue, high tracer input cost, low volume, structurally distinct economics

Larger groups may add a fifth bucket for mammography or interventional procedures. The principle is the same: decompose to the level where the economics are actually distinct, and stop there.

Bucket 1 — MRI

The marketing engine of most imaging centers. High billed amounts, prestige modality, and the modality patients and referring physicians most identify with.

The economic reality:

MRI is the highest-LOP-concentration modality at most SE Florida imaging centers, which means MRI is also the highest gap between face-value A/R and yield-adjusted A/R. (See the related framework in LOP Economics: Real Yield vs Face Value.)

Healthy MRI contribution margin at a well-managed SE Florida center: 35–55% of collected revenue, depending on payer mix.

Bucket 2 — CT

The throughput business. Faster slot time than MRI, cleaner payer mix (more Medicare, less LOP), and structurally easier to scale.

The economic reality:

CT is the workhorse modality. It rarely produces the headline-grabbing per-claim revenue of MRI or PET, but it produces predictable cash with relatively clean DSO. (For broader context on payer-class DSO behavior across modalities, see DSO Benchmarks for Imaging Centers: 2026 SE Florida Data.)

Healthy CT contribution margin: 40–60% of collected revenue.

Bucket 3 — Ultrasound (with X-ray and DEXA)

The volume business. Low per-claim revenue, very low variable cost, fast cash conversion, low payer drama.

The economic reality:

Ultrasound, X-ray, and DEXA produce small dollars per claim but excellent contribution margin and the fastest cash. They are the modalities that fund the business while the prestige modalities collect the headlines.

Healthy contribution margin: 50–70% of collected revenue.

Bucket 4 — PET Tracer Scans

The structurally distinct modality. PET Tracer Scans are not "imaging" in the same financial sense as MRI, CT, or ultrasound — they are a tracer-pass-through-plus-margin business that sits inside the imaging center's four walls but operates on different economics.

The economic reality:

The defining feature of PET Tracer Scans is that a meaningful share of every encounter's revenue is pre-spent on the tracer dose. A scan that doesn't get reimbursed doesn't just lose contribution margin — it loses the tracer cost in cash. The economic discipline required to run a PET Tracer Scan business is fundamentally different from the rest of the imaging operation.

This is why we run PET Tracer Scans as a separate business unit on every Two-Business-Unit P&L decomposition: rolling tracer-pass-through economics into general imaging hides the single largest profit-or-loss driver in modern radiology.

Healthy PET Tracer Scan contribution margin: 25–45% of collected revenue when payer mix and prior-auth discipline are operating well; structurally negative when they are not. (For more on toxic combinations: 7 Payers, 41 Procedures, $80,593 Lost.)

The Decomposed P&L — A Worked Example

Here is the same $11.8M imaging center, with the modality decomposition applied:

Modality Volume Revenue Variable Cost Direct Labor Contribution $ Contribution %
MRI 7,200 scans $5,184,000 $325,000 $612,000 $4,247,000 81.9%
CT 9,400 scans $3,196,000 $188,000 $282,000 $2,726,000 85.3%
Ultrasound / X-ray / DEXA 14,600 scans $1,898,000 $35,000 $292,000 $1,571,000 82.8%
PET Tracer Scans 480 scans $1,536,000 $1,008,000 $96,000 $432,000 28.1%
Total 31,680 $11,814,000 $1,556,000 $1,282,000 $8,976,000 76.0%

Three things jump off the page once the report exists:

  1. PET Tracer Scans are pulling 28% contribution against the rest of the business at 80%+. That gap is not a problem in itself — PET Tracer Scans are structurally tracer-pass-through. But the gap reveals where prior-auth discipline, payer selection, and toxic-combination management need to live. (See: The Most Expensive 2-Minute Decision in Your Medical Practice.)
  2. Ultrasound throws off $1.57M of contribution at 14,600 scans of low-glamour volume. This is the modality that is actually paying the rent in most SE Florida imaging centers — and the one the marketing budget rarely supports.
  3. MRI's $4.25M contribution looks healthy in dollars, but its 81.9% rate hides the LOP and PIP exposure. Run the per-payer DSO and yield analysis on MRI specifically and the cash story gets less rosy than the contribution-margin story.

This decomposition takes a competent finance person 4–8 hours to build the first time. It takes 30 minutes a month to maintain once the data flow is set up. Most imaging operators never build it because their accountant is producing tax-compliance-format financials and their billing company is not paid to produce management reporting.

Cost Allocation — Where the Math Gets Honest

The biggest pitfall in modality-level P&L is fixed-cost allocation. Three approaches in increasing rigor:

Naive allocation (avoid): square footage. Allocates rent and utilities by floor space the modality occupies. Penalizes high-throughput low-footprint modalities (ultrasound) and undercredits low-throughput high-footprint ones (MRI).

Better allocation: revenue share. Allocates fixed cost as a percentage of each modality's revenue. Easier to compute, but creates a circularity that disadvantages high-revenue modalities and advantages low-revenue ones.

Right allocation: scan-time-weighted. Allocates fixed cost by share of total scan time the modality consumes — which is also the share of capacity it consumes. PET Tracer Scans take 90 minutes per scan; ultrasound takes 25; the fixed-cost allocation should reflect that.

The scan-time-weighted approach matches contribution margin with actual capacity utilization, which is the question owners are usually trying to answer ("which modality should I expand?") even when they don't know how to phrase it.

Capital Allocation — The Question This Report Is Built For

Once the per-modality P&L is real, the capital-allocation conversation changes from "which modality has the best growth story" to "which modality produces the best contribution dollars per dollar of incremental capital."

The natural questions:

These are not theoretical questions. They are the four questions every SE Florida imaging owner is making decisions about right now — usually without the per-modality P&L that turns the decisions into math.

The Tax Layer

Modality-level segmentation has tax-planning implications that compound the management-reporting benefits:

The point is not that modality segmentation creates new tax strategies — it's that modality segmentation gives you the data resolution to execute the tax strategies competently. Most imaging-center tax work today is done at a resolution that's invisible to the actual business inside the center.

Five Actions for SE Florida Imaging Operators

1. Re-build your last 12 months of P&L with modality as the primary segmentation axis. Volume from the billing system. Variable cost from supplies and tracer purchasing data. Direct labor from time-tracking or estimated allocation. Fixed cost via scan-time-weighting. The 4–8 hour upfront investment unlocks every subsequent decision.

2. Run contribution margin by modality, by month, for 12 months. You're looking for trends, not just point-in-time numbers. A modality whose contribution margin has drifted 7 points over four quarters is telling you something the headline EBITDA cannot.

3. Cross-tabulate modality contribution against payer mix. The MRI bucket may be 80% contribution overall but 35% contribution on the LOP-heavy slice and 90% on the Medicare slice. Capacity allocation should follow the math, not the marketing pitch.

4. Match capital-allocation decisions to per-modality contribution. The next $400K of equipment spend should go to the modality where each incremental dollar of capacity converts most efficiently into contribution dollars. The data to make that decision is in the per-modality P&L.

5. Build modality segmentation into the year-over-year tax plan. Bonus depreciation, R&D credits, equipment placed-in-service timing — all of it gets sharper with modality data. Without it, year-end tax work is happening at a resolution that's blind to the actual business.

What This Looks Like for an Operator

Your billing data has every number this report requires. Your payroll system has every number this report requires. Your equipment list has every number this report requires. The question is whether anyone is integrating those three sources into a single per-modality view that turns "imaging" from one number into four businesses.

The four-center group from the opening of this article ran the modality decomposition during a Strategic Radiology Review. The analysis exposed a PET Tracer Scan program running structurally negative on three specific commercial payer combinations, an MRI bucket whose headline contribution masked an LOP yield problem, and an ultrasound operation whose 67% contribution margin had been quietly carrying the entire group.

Within 60 days, the operator declined two specific PET Tracer Scan payer combinations, redirected $300K of planned MRI capital toward a third ultrasound unit and a sonographer, and re-cut the next year's budget around modality contribution dollars instead of modality volume. The next quarter's contribution dollars were $187K higher than the prior comparable quarter — on lower total scan volume.

Most accounting firms see a 16% EBITDA and move on. The operator sees a healthy headline. Both are looking at the same number — and both are missing the same problem. This is what happens when accounting stops looking backward and starts looking forward. (Read how accounting becomes an ROI center, not a cost center.)

The Monday after the modality P&L hit the operator's desk, he told us it was the first financial report he had seen in 11 years that actually told him which business he was running. Four businesses, four contribution profiles, four capital-allocation conversations. One operating company.

Ready to Decompose Your P&L by Modality?

A Strategic Radiology Review is a fixed-fee, two-week engagement that produces the per-modality contribution analysis described in this article — alongside Two Business Unit P&L decomposition, per-payer-class DSO benchmarking, and a banker-grade Intelligence PDF built specifically for multi-center SE Florida imaging operators.

Book a Strategic Radiology Review →

Frequently Asked Questions

What is a healthy contribution margin for an imaging modality? Targets vary by modality: MRI 35–55%, CT 40–60%, ultrasound/X-ray/DEXA 50–70%, and PET Tracer Scans 25–45% net of tracer cost. The absolute number matters less than internal consistency: a modality drifting 7+ points off its prior trailing-12-month average is signaling something the headline P&L will not.

How do I allocate fixed costs across modalities? Scan-time-weighted allocation matches fixed cost to capacity consumption and produces the most defensible per-modality contribution figure. Square-footage allocation is the most common but penalizes high-throughput modalities. Revenue-share allocation creates a circularity that biases the math.

Should PET Tracer Scans be reported as a separate business unit? Yes. Tracer pass-through economics make PET Tracer Scans structurally distinct from general imaging, and rolling them into a single imaging line hides the largest profit-or-loss driver in a modern center. The Two Business Unit Framework breaks PET Tracer Scans out as a separate operating segment with its own P&L, its own DSO, and its own capital-allocation logic.

How long does it take to build modality-level P&L? First time: 4–8 hours of finance and billing-data work to construct the prior-12-months baseline. Ongoing: 30 minutes per month to maintain once the data pipeline is set up. The cost is overwhelmingly upfront; the benefit compounds every month thereafter.

Will my CPA or accountant produce this report? Almost never, unless explicitly asked. Standard accounting deliverables are tax-compliance-format financials, which roll modalities into a single imaging line. Producing modality-level management reports requires a different scope, different data inputs, and different reporting cadence — which is why most imaging centers have to build this view outside their compliance accounting workflow.

Disclaimer: This article is for informational purposes only and does not constitute tax, legal, or financial advice. Tax situations vary — consult a qualified tax professional for advice specific to your circumstances. Practice examples are anonymized composites based on real client data; identifying details have been changed.