Quick answers
- Which hospitals does Ronald Lessen work at?
- Medicare's official clinician data lists Ronald Lessen at 2 hospitals: Long Island Jewish Medical Center and North Shore University Hospital. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does Ronald Lessen see patients?
- Medicare's clinician data lists 1 practice location in Manhasset, NY. Call before your visit to confirm the address.
- What is Ronald Lessen's specialty?
- Medicare lists Anesthesiology as the primary specialty.
- Does Ronald Lessen accept Medicare assignment?
- Yes. Medicare's clinician data says Ronald Lessen 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 Ronald Lessen?
- (516) 562-0100, as listed in official Medicare / NPI Registry data.
- What is Ronald Lessen's NPI number?
- 1588660328. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where Ronald Lessen works
Medicare's Facility Affiliation Data lists Ronald Lessen at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Long Island Jewish Medical CenterNew Hyde Park, NY · Acute Care Hospital · CCN 330195
- North Shore University HospitalManhasset, NY · Acute Care Hospital · CCN 330106
Practice locations
Addresses where Ronald Lessen is enrolled with Medicare (CMS data updated 2026-10-02).
- 300 Community DrManhasset, NY 11030 (516) 562‑0100
Group practices
Medicare enrollment lists Ronald Lessen as a member of this group (CMS data updated 2026-10-02).
- North Shore - Lij Anesthesiology, PC1,003 clinicians in the group
Specialties
- Anesthesiologyprimary
Other anesthesiologists in Manhasset
Clinicians with the same Medicare primary specialty in Manhasset, NY — not a recommendation.
Clinician information
| Graduation year | 1992 |
|---|---|
| Gender (as listed) | Female |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1588660328 |
| Corrections | Report 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
- Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated 2026-10-02, retrieved 2026-10-29
- National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians