Greggory Gahn, MD
Retina Specialist · Reno, NVNPI 1720541147
Payments from drug & device makers
What this record shows
The money is spread across several categories — consulting fees (37.7%), food and beverage and travel and lodging — rather than concentrated in one kind of arrangement. 20 manufacturers reported payments, led by Genentech USA, Inc. at 48.0% of the total. 2025 is the largest year on record at $7,291, more than ten times the $146 reported in 2020.
Across 141 payments — averaging $102.95 each. Meals, travel, consulting and speaking fees, gifts and royalties reported by drug and device makers.
- Genentech USA, Inc.$7K
- Alcon$3K
- Bausch & Lomb Americas Inc.$2K
- Astellas Pharma US Inc$715
- AbbVie$317
- Glaukos Corporation$257
- plus $1K from 14 others
What the payments were for
- Consulting fees$5,47538%
- Travel & lodging$3,59025%
- Food & beverage$5,35137%
- Education$1001%
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 |
|---|---|---|
| Genentech USA, Inc. | 34 | $6,962 |
| Alcon | 24 | $2,734 |
| Bausch & Lomb Americas Inc. | 26 | $2,319 |
| Astellas Pharma US Inc | 22 | $715 |
| AbbVie(2 entities) | 6 | $317 |
| Glaukos Corporation | 4 | $257 |
| Harrow Eye, LLC | 5 | $241 |
| Ocular Therapeutix, Inc. | 2 | $151 |
| Rxsight Inc | 1 | $134 |
| Johnson & Johnson | 1 | $125 |
| Dompe US, Inc. | 1 | $125 |
| Regeneron Healthcare Solutions, Inc. | 1 | $96 |
| Sight Sciences, Inc. | 3 | $92 |
| ANI Pharmaceuticals, Inc. | 3 | $66 |
| Neurotech Pharmaceuticals, Inc. | 3 | $59 |
| Oyster Point Pharma, Inc. | 1 | $34 |
| Johnson & Johnson Surgical Vision, Inc. | 1 | $26 |
| Astellas Pharma Global Development | 1 | $23 |
| Carl Zeiss Meditec Cataract Technology Inc. | 1 | $20 |
| Alimera Sciences, Inc. | 1 | $19 |
What the payments were tied to
Products named in the reported payments. Only payments of $100 or more are attributed here — the typical reported payment nationally is a meal worth about $16, and listing those product-by-product would be noise.
- SUSVIMO$6,263
- STELLARIS ELITE$1,693
- Crystalens Accommodating IOL (AT-52AO)$1,693
- enVista MX60 IOL$1,693
- Trulign IOL$1,693
- Akreos AO IOL$1,693
- Constellation$160
- IACCESS$140
- iStent inject W$140
- LIGHT ADJUSTABLE LENS (LAL) AND LIGHT DELIVERY DEVICE (LDD)$134
- DEXTENZA$133
- MATRIXMIDFACE$125
- Rocklatan$125
- Rhopressa$125
- IHEEZO$125
- TRIESENCE$125
- Oxervate$125
- AcrySof Toric Aspheric UV Absorbing IOL$120
- VABYSMO$116
- DURYSTA$115
How this compares
Too few retina specialist providers in Nevadato place this figure against a meaningful peer group, so we don't.
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 | 228 | $9,227 |
| Dorzolamide-TimololDorzolamide Hcl/Timolol Maleat | 54 | $856 |
| MoxifloxacinMoxifloxacin Hcl | 15 | $363 |
| ErythromycinErythromycin Base | 31 | $355 |
| Timolol Maleate | 17 | $207 |
| Neomycin-Polymyxin-DexamethNeomycin/Polymyxin B/Dexametha | 17 | $167 |
| Brimonidine Tartrate | 19 | $115 |
Paid to pharmacies, not to this prescriber.
Other retina specialist in Reno
- Spencer FullerReno$6K
- William StevensonReno$5K
- Wen-Shi ShiehReno$310
- George ParLas Vegas$110K
- Chris WuLas Vegas$11K
- Russell JayneLas Vegas$8K
- Charles CalvoLas Vegas$2K
- Alec AmramLas Vegas$1K
- Tyson WardLas Vegas$1K
- John GunnHenderson$1K
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.