Dr. Errol Grannum, MD
What this data tells you about Dr. Grannum
Dr. Errol Grannum is an ophthalmology specialist in Mcallen, TX, with 20 years of NPI registration. Based on federal Medicare data, Dr. Grannum performed 1,706 Medicare services in 2023. These records do not provide a deduplicated patient total.
Between the years covered by Open Payments, Dr. Grannum received a total of $1,563 from 11 pharmaceutical and/or device companies across 69 payment records. A record can group multiple payments. These transfers are publicly reported through CMS Open Payments. Disclosure alone does not establish their effect on care. A reliable breakdown by payment category is not available in this snapshot. Patients may wish to discuss these relationships with their provider.
The Data Coverage level for Dr. Grannum is Very High — reflecting how much public federal data is available about this provider. Patients are encouraged to use this data as one of several factors when choosing a healthcare provider.
Medicare Practice Summary — 2023
Medicare Utilization ↗Top procedures by volume
Ranked by number of services performed for Medicare patients. Avg. submitted charge is what the provider billed; avg. Medicare payment is what CMS paid.
| Procedure | Volume | Avg. paid | Avg. submitted |
|---|---|---|---|
| Eye exam, established patient, focused A limited examination of the visual system for an existing patient. The provider focuses on a specific eye-related concern or symptom. |
659 | $62 | $150 |
| Measurement of corneal pressure | 332 | $8 | $25 |
| Visual field test, extended A test that maps your complete field of vision to detect blind spots or peripheral vision loss. Extended testing provides a more detailed assessment than a standard visual field exam. |
169 | $44 | $225 |
| Eye drainage system examination An examination of the internal drainage system of the eye to assess how fluid flows and drains from the eye. |
147 | $19 | $120 |
| Optic nerve imaging (OCT scan) Imaging of the optic nerve. |
143 | $24 | $300 |
| New patient office visit (45-59 min) An initial office visit for a new patient lasting between 45 and 59 minutes. This code covers the total time spent by the physician or qualified healthcare professional on the date of the encounter. |
84 | $102 | $300 |
| Retinal photography (fundus photo) This procedure involves taking photographs of the retina, the light-sensitive tissue at the back of the eye. It is used to document the condition of the eye's interior structures. |
50 | $25 | $200 |
| Laser repair to improve eye fluid flow A laser procedure used to enhance the drainage of fluid within the eye. |
31 | $157 | $1,800 |
| Ultrasound scan of cornea to determine thickness An ultrasound procedure used to measure the thickness of the cornea. |
30 | $8 | $100 |
| Eyelash removal with forceps This procedure involves the manual removal of eyelashes using forceps. It is a mechanical extraction method performed on the eyelid area. |
29 | $14 | $120 |
| Laser eye fluid drainage tract creation A laser procedure used to create drainage tracts in the iris to help fluid flow out of the eye. |
20 | $218 | $1,400 |
| Extended eye exam with retinal drawing A detailed examination of the back of the eye that includes creating a drawing of the retina. |
12 | $16 | $125 |
Industry Payment Transparency
Open Payments through 2024 ↗Payment categories are unavailable while the source breakdown is being rebuilt. Company and year totals do not identify how much belongs to each category.
Payment trend by year
Annual totals from pharmaceutical and medical device companies.
Payments by company (2024)
All-time payments by company (2018-2024) ›
Associated products mentioned in payments ›
Geographic Context
0.0 mi
Data Sources
| Provider Registry | ✓ NPPES | NPPES snapshot; verify current record |
| Medicare Enrollment | ✓ PECOS | PECOS snapshot |
| Practice Data | ✓ Medicare Util. | Annual (CY lag) |
| Industry Payments | ✓ Open Payments | CY 2024 |
| Disciplinary History | — Not included | N/A |
This provider has data in 4 of 4 available federal datasets, with a Data Coverage level of Very High. This reflects how much public data is available about a provider. How we calculate this →
Summary
Dr. Grannum is a mixed practice specialist, with moderate Medicare volume, with 20 years of NPI registration.
This summary is auto-generated from federal data, describing data availability and patterns. Read our methodology →
Frequently Asked Questions
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This page combines public CMS records with calculated summaries and explanatory procedure labels. These transformations are not verbatim federal records. Sources: NPPES ↗, Open Payments ↗, Medicare Provider Utilization ↗, and PECOS. Publication is mandated by the Physician Payments Sunshine Act (§6002 ACA, 42 U.S.C. §1320a-7h) and the Freedom of Information Act.
This page is not medical advice, an endorsement, a recommendation, or a quality rating. Data Coverage reflects data completeness — how much federal information exists for this provider — not clinical performance, patient outcomes, or quality of care. Always verify information directly with the provider and consult a licensed clinician before making medical decisions.
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