Gregory Christensen, MD
Ophthalmology · Greenville, SCNPI 1851374482
Payments from drug & device makers
What this record shows
This record is dominated by ownership interests: $2,121 of the $2,839 with a category attached, or 74.7%. US Retina LLC accounts for 74.7% of it on its own, with 7 other manufacturers making up the rest. Reporting peaked in 2022 at $1,118 and has fallen 95.4% since, to $51 in 2024.
Across 44 payments — averaging $64.52 each. Meals, travel, consulting and speaking fees, gifts and royalties reported by drug and device makers.
- US Retina LLC$2K
- Regeneron Healthcare Solutions, Inc.$335
- Genentech USA, Inc.$186
- Novartis$86
- Bausch & Lomb, A Division Of Bausch Health US, LLC$63
- Apellis Pharmaceuticals, Inc.$19
- plus $29 from 2 others
What the payments were for
- Food & beverage$71725%
- Ownership interest$2,12175%
General payments by program year
Who reported the general payments
Companies are grouped under their corporate parent — a single manufacturer often files under several CMS reporting entities. Research and ownership payments are counted separately and are not in this table.
| Company | Payments | Total |
|---|---|---|
| US Retina LLC | 6 | $2,121 |
| Regeneron Healthcare Solutions, Inc. | 14 | $335 |
| Genentech USA, Inc. | 12 | $186 |
| Novartis | 5 | $86 |
| Bausch & Lomb, A Division Of Bausch Health US, LLC | 4 | $63 |
| Apellis Pharmaceuticals, Inc. | 1 | $19 |
| Bausch & Lomb Americas Inc. | 1 | $16 |
| AbbVie | 1 | $13 |
How this compares
$2,839 in reported general payments places this provider in the 60th percentile of 293 ophthalmology providers in South Carolina.
Medicare billing
What this is not: this is the amount Original Medicare Part B allowed for services this provider billed in 2024. It is not their income. It excludes Medicare Advantage — now more than half of all Medicare enrollment — along with Medicaid and all commercial insurance, and it is gross practice revenue before staff, rent, supplies and malpractice premiums. CMS also suppresses any figure covering ten or fewer patients, so low-volume providers appear smaller than they are.
Most prescribed under Part D
| Drug | Claims | Cost to plans & patients |
|---|---|---|
| Prednisolone Acetate | 164 | $8,465 |
| Ketorolac Tromethamine | 140 | $4,654 |
| Bromfenac Sodium | 15 | $1,626 |
| Latanoprost | 85 | $849 |
| Timolol Maleate | 90 | $841 |
| Dorzolamide-TimololDorzolamide Hcl/Timolol Maleat | 29 | $502 |
| Brimonidine Tartrate | 30 | $435 |
| Dorzolamide Hcl | 23 | $255 |
| Neomycin-Polymyxin-DexamethNeomycin/Polymyxin B/Dexametha | 13 | $125 |
| Diclofenac Sodium | 12 | $101 |
Paid to pharmacies, not to this prescriber.
Other ophthalmology in Greenville
- Alan LeaheyGreenville$35K
- William BallingerGreenville$14K
- Dilip ThomasGreenville$8K
- Brian WelcomeGreenville$7K
- Kerry SolomonMt Pleasant$1.7M
- William ClarkWest Columbia$768K
- George WaringMt Pleasant$645K
- Karolinne RochaCharleston$552K
- Joseph BishopHilton Head Island$136K
- Erik HappMt Pleasant$124K
Where these figures come from
- Payments: CMS Open Payments, program years 2019–2025 (publication P06302026_06032026).
- Billing: Medicare Physician & Other Practitioners, data year 2024. Original Medicare Part B only.
- Identity: NPPES NPI Registry, July 2026.