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MARGARET A GREVEN M.D.
NPI 1821380874
Ophthalmology in Winston Salem, NC

Active since May 10, 2011PECOS EnrolledAccepts Medicare Assignment
MEDICAL CENTER BLVD DEPT OF OPHTHALMOLOGY, WINSTON SALEM, NC 27157(336) 716-4091 Get Directions Write a Review

NPPES record last updated: July 21, 2022. Verified against the NPPES registry weekly; last sync: October 25, 2026.

About Margaret A Greven M.d. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

MARGARET A GREVEN M.D. (NPI 1821380874) is an individual ophthalmology provider in Winston Salem, North Carolina, licensed in North Carolina (2017-01126) and active in the NPI registry since May 2011. She is enrolled in Medicare PECOS, is affiliated with Novant Health Forsyth Medical Center, and is a graduate of Other (2011).

NPPES Registry Identity

NPI1821380874
Entity TypeIndividualFemale
Primary Taxonomy207W00000X
Provider Legal NameMARGARET A GREVENCredential: M.D.
Location AddressMEDICAL CENTER BLVD DEPT OF OPHTHALMOLOGYWinston Salem, NC 27157-3216
Mailing AddressPo Box 602658Charlotte, NC 28260-2658 · (336) 716-2011
Phone(336) 716-4091
Sole ProprietorNo
Medical School CMSOtherGraduated 2011
Enumeration DateMay 10, 2011
Last NPPES UpdateJuly 21, 2022
✔ NPI 1821380874 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyOphthalmologyAllopathic & Osteopathic Physicians
Taxonomy Code207W00000X
License✔ Licensed in NC · 2017-01126
Definition
An ophthalmologist has the knowledge and professional skills needed to provide comprehensive eye and vision care. Ophthalmologists are medically trained to diagnose, monitor and medically or surgically treat all ocular and visual disorders. This includes problems affecting the eye and its component structures, the eyelids, the orbit and the visual pathways. In so doing, an ophthalmologist prescribes vision services, including glasses and contact lenses.
MEDICAL CENTER BLVD DEPT OF OPHTHALMOLOGY, Winston Salem, NC 27157
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Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Ambetter from Absolute Total Care, Ambetter Health, Ambetter of North Carolina and more.Insurance ›

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Margaret A Greven M.d. is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID3971735978
PECOS Enrollment IDI20171002000464
Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignment

Medicare enrollment records show Margaret Greven reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Wake Forest University Health Sciences
Same address
Multi-Specialty
MEDICAL CENTER BLVD
Winston Salem, NC 27157
  • Reassigned Medicare billing, North Carolina enrollment
  • 3,003 clinicians in this Medicare group
NPI 1003803032 (336) 716-2255

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Areas of Expertise CMS Part B claims 11

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Injection, faricimab-svoa, 0.1 mg J2777
Faricimab-svoa is a medication given through an injection into the eye to treat certain eye conditions. The 0.1 mg dosage helps control disease progression, improving vision and eye health. The procedure is done by a healthcare professional.
3,000 services20 patients
Imaging of retina 92134
Imaging of the retina is a non-invasive procedure that captures detailed images of your eye's interior. This helps detect conditions like macular degeneration or retinal detachment. It's painless and takes only a few minutes.
941 services395 patients
Injection of drug into eye 67028
An injection into the eye is a procedure where a medication is delivered directly into your eye to treat various conditions. A local anesthetic is applied to numb the eye, ensuring minimal discomfort. The drug helps manage diseases like macular degeneration or diabetic retinopathy.
573 services126 patients
Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more 99213
This is a routine visit for patients who have already been seen by the healthcare provider. During this approximately 20-29 minute appointment, your health status will be evaluated and any necessary treatments or tests will be discussed. It's a chance to address any health concerns you may have.
415 services292 patients
Imaging of retina 92134
Imaging of the retina is a non-invasive procedure that captures detailed images of your eye's interior. This helps detect conditions like macular degeneration or retinal detachment. It's painless and takes only a few minutes.
214 services87 patients
Injection, aflibercept, 1 mg J0178
Aflibercept injection is a treatment for certain eye conditions that affect vision. It works by blocking abnormal blood vessel growth and leakage in the eye, which can cause vision loss. The medication is administered directly into the eye by a healthcare professional.
166 services14 patients

Hospital Affiliations CMS Care Compare 2

Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.

Novant Health Forsyth Medical Center

Acute Care Hospitals · Winston-Salem, NC
3/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number340014
Location3333 Silas Creek ParkwayWinston-Salem, NC 27103 · Forsyth County
Emergency services Birthing friendly

North Carolina Baptist Hospital

Acute Care Hospitals · Winston-Salem, NC
3/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number340047
LocationMedical Center BoulevardWinston-Salem, NC 27157 · Forsyth County
Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 27157 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$125.01 typical visit price
range $54.12 – $165.09
Typical copayment $31.25 (range $13.53 – $41.27)
Most-billed visit code 99204
Established Patient
$67.72 typical visit price
range $17.21 – $134.61
Typical copayment $16.93 (range $4.30 – $33.65)
Most-billed visit code 99213
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Margaret Greven's NPI number?

The NPI number for Margaret Greven is 1821380874. It was assigned to this individual provider in the NPPES registry on May 10, 2011.

Where is Margaret Greven located?

Margaret Greven practices at Medical Center Blvd Dept Of Ophthalmology, Winston Salem, NC 27157. The listed phone number is (336) 716-4091.

What is Margaret Greven's specialty?

The primary specialty registered for this NPI is Ophthalmology with taxonomy code 207W00000X.

Is Margaret Greven enrolled in Medicare?

Yes. Margaret Greven is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

Which organization bills Medicare for Margaret Greven's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Margaret Greven reassigns Medicare benefits to Wake Forest University Health Sciences (Winston Salem, NC). The reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Margaret Greven's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Margaret Greven accept?

Health plans from Ambetter Health, Ambetter from Absolute Total Care, Ambetter of North Carolina, Ambetter of Tennessee and AmeriHealth Caritas Next and 8 other insurers list Margaret Greven as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

Is Margaret Greven affiliated with any hospitals?

According to CMS data, Margaret Greven is affiliated with Novant Health Forsyth Medical Center and North Carolina Baptist Hospital.

When was this NPI record last updated?

The NPPES record for Margaret Greven was last updated on July 21, 2022. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 4 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.