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Ophthalmology

Marc Dinowitz, MD

Works at hospitals in Riverhead, NY · New York

Summary

Marc Dinowitz, MD (Ophthalmology) is listed by Medicare at 1 hospital in Riverhead, NY. NPI 1578582466. Medicare data says the clinician accepts Medicare assignment. Source: CMS Facility Affiliation Data, updated 2026-10-02.

From official Medicare data

This page shows what Medicare's official clinician data says about Marc Dinowitz, joined by NPI number (data updated 2026-10-02). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

At a glance

OphthalmologyPrimary specialty
YesAccepts Medicare assignment
30Years since medical school (graduated 1996)
State University Of New York At Stony Brook, School Of MedicineMedical school
MaleGender (as listed)
North Shore-Lij Medical PCGroup practice

Quick answers

Which hospitals does Marc Dinowitz work at?
Medicare's official clinician data lists Marc Dinowitz at 1 hospital: Peconic Bay Medical Center. This is where the clinician works or has privileges; call the hospital to confirm.
Where does Marc Dinowitz see patients?
Medicare's clinician data lists 1 practice location in Port Jefferson, NY. Call before your visit to confirm the address.
What is Marc Dinowitz's specialty?
Medicare lists Ophthalmology as the primary specialty.
Does Marc Dinowitz accept Medicare assignment?
Yes. Medicare's clinician data says Marc Dinowitz accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of 2026-10-02. Ask the office to confirm before your visit.
What is the phone number for Marc Dinowitz?
(631) 473-1320, as listed in official Medicare / NPI Registry data.
What is Marc Dinowitz's NPI number?
1578582466. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Hospitals where Marc Dinowitz works

Medicare's Facility Affiliation Data lists Marc Dinowitz at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.

Practice locations

Addresses where Marc Dinowitz is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists Marc Dinowitz as a member of this group (CMS data updated 2026-10-02).

  • North Shore-Lij Medical PC6,440 clinicians in the group

Specialties

Find other Ophthalmology doctors in New York →

Other ophthalmologists in Port Jefferson

Clinicians with the same Medicare primary specialty in Port Jefferson, NY — not a recommendation.

All ophthalmologists in Port Jefferson →

Clinician information

CredentialMD
Medical schoolState University Of New York At Stony Brook, School Of Medicine
Graduation year1996
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1578582466
CorrectionsReport an error or suggest an update →

Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.

Sources

  1. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated 2026-10-02, retrieved 2026-10-29
  2. National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
  3. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  4. Medicare Care Compare — official Medicare tool to look up clinicians