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Edit this profileAt a glance
- 808 Rickert Dr Ste 201, Naperville, IL 60540
About Dr. Ahn
Based in Naperville, IL, Charles S. Ahn, MD is listed in the NPI registry under ophthalmology. Charles graduated from University of Michigan Medical School in 1993. According to Medicare claims data, Charles cared for 1,275 Medicare patients across 1,575 services. The services billed most often include established patient complete exam of visual system, removal of cataract with insertion of prosthetic lens, and measurement of corneal curvature and depth of eye. NPI 1942260278 identifies this record in the national registry.
Factual summary compiled by Guide.md from public records; not written by this provider.
Education & Training
Specialty
Credentials & Licensing
Medicare information
Exactly as CMS reports it (National Downloadable File, Opt-Out Affidavits, Order & Referring). Not an insurance directory; confirm coverage with the office.
Contact Information
- (630) 355-8000
- Email not available
Practice Locations
808 RICKERT DR STE 201
Naperville, IL 60540
Conditions Commonly Evaluated or Treated
Within Ophthalmology generally. Availability varies by clinician, training and location — this profile has not been claimed, so nothing here is a personal claim by the provider.
Conditions
Most searched conditions
Cornea and external eye
Eyelid and tear drainage
Refractive and focusing
- Astigmatism
- Eye misalignment (strabismus)
- Farsightedness
- Lazy eye (amblyopia)
- Nearsightedness
- Presbyopia
Retina and vitreous
Eye injuries
Inflammation, neurologic, and orbit
Retina & vitreous
Procedures & services
Most searched procedures
Examination and imaging
Cataract and lens
Corneal procedures
Eye diagnostics
Eye injuries
Eyelid surgery
Eyelid, tear duct, and muscle
Glaucoma
- Glaucoma drainage-device implantation
- Laser peripheral iridotomy
- Minimally invasive glaucoma surgery
- Selective laser trabeculoplasty
Laser eye surgery
Laser procedures
Laser vision correction
Refractive surgery
Tear duct & Orbit
Procedures Most Often Billed to Medicare
1,575 services · 1,275 patients · 12 distinct codes
| Procedure | Type | Code | Services | Compared with peers |
|---|---|---|---|---|
| Removal of cataract with insertion of prosthetic lens | Procedure | 66984 |
287 | More often than most peers in Ophthalmology |
| Removal of recurring cataract in lens capsule using a laser | Procedure | 66821 |
122 | More often than most peers in Ophthalmology |
| Creation of eye fluid drainage tracts in iris using a laser, per session | Procedure | 66761 |
16 | Less often than most peers in Ophthalmology |
| Transplantation of outer layer of corneal tissue | Procedure | 65756 |
15 | Less often than most peers in Ophthalmology |
| Established patient complete exam of visual system | Treatment | 92014 |
487 | More often than most peers in Ophthalmology |
| Measurement of corneal curvature and depth of eye | Treatment | 92136 |
271 | More often than most peers in Ophthalmology |
| Established patient problem focused exam of visual system | Treatment | 92012 |
178 | As often as other peers in Ophthalmology |
| New patient complete exam of visual system | Treatment | 92004 |
136 | More often than most peers in Ophthalmology |
| Ct scan of cornea | Treatment | 92025 |
19 | Less often than most peers in Ophthalmology |
| Imaging of front third of eye using a special microscope | Treatment | 92286 |
18 | Less often than most peers in Ophthalmology |
Source: CMS Medicare public data. Shows how often procedures were billed — not quality of care or patient satisfaction.
Related providers
Connections drawn from the registry and from what providers have told us. A link here is not a referral or an endorsement.
Other eye doctors at this location 3
Same specialty, same street address — most likely the same department or group.
Related specialists at this location 6
Clinically related specialties at the same address — the people this provider most likely works alongside.
Also at this address 4
Providers at the same street address. Each files their own registry entry, so a shared practice often appears under several different names.
More connections — 32 related providers in 4 groups
Other eye doctors in Naperville 8
Same specialty, same city.
Trained at University of Michigan Medical School 8
Other providers in the same specialty who trained at the same institution.
Class of 1993 at University of Michigan Medical School 8
Providers who graduated from the same medical school in the same year.
Also performs Removal of cataract with insertion of prosthetic lens 8
Providers in IL who bill this service to Medicare most often.
Common questions
What kind of doctor is Dr. Ahn?
Dr. Ahn is an eye doctor in Naperville, IL. That is the designation recorded for this NPI in the federal registry, where it is listed as “Ophthalmology”.
NPI registry
What is Dr. Ahn's address?
Dr. Ahn is listed at 808 Rickert Dr Ste 201, Naperville, IL 60540. Addresses come from the NPI registry and can lag a move, so confirm before travelling.
NPI registry
How can I make an appointment with Dr. Ahn?
The number on file is (630) 355-8000. Contact the office directly to confirm availability and scheduling.
NPI registry
What is Dr. Ahn's NPI number?
Dr. Ahn's National Provider Identifier is 1942260278. It is issued by the Centers for Medicare & Medicaid Services and is unique and permanent — it does not change if they move practice.
NPI registry
Where did Dr. Ahn train?
Dr. Ahn attended University of Michigan Medical School, graduating in 1993. This comes from the CMS National Downloadable File.
CMS public data
How long has Dr. Ahn been practicing?
Dr. Ahn has 33 years experience. Calculated from a graduation year of 1993, reported in the CMS National Downloadable File.
CMS public data
What procedures does Dr. Ahn perform?
According to Medicare billing data, Dr. Ahn performs procedures including removal of cataract with insertion of prosthetic lens, removal of recurring cataract in lens capsule using a laser and creation of eye fluid drainage tracts in iris using a laser, per session; provides treatments such as established patient complete exam of visual system and measurement of corneal curvature and depth of eye, alongside routine visits and testing. This reflects Medicare patients only and is billing volume, not a measure of quality.
Medicare claims
Has Dr. Ahn confirmed this information?
Not yet. This profile is built from public federal data and has not been confirmed by Dr. Ahn. If this is you, claiming it is free.
Guide.md
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