Physician Profile
Joann CONG YIN Chang, M.D.
Unclaimed ProfileAbout Dr. Chang
Joann CONG YIN Chang, M.D. practices ophthalmology in Lancaster, MA. Joann is a 2004 graduate of University of Cincinnati College of Medicine. According to Medicare claims data, Joann cared for 2,247 Medicare patients across 3,098 services. The services billed most often include measurement of corneal curvature and depth of eye, established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more, and established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more.
Summarised automatically from public NPI registry and CMS Medicare data. Not written or reviewed by this provider. Claim this profile to replace it — free, and no identity document with a practice or institutional email.
Education & Training
Specialty
Credentials & Licensing
License numbers are what the provider reported to NPPES when the NPI was issued or updated. NPPES does not verify licensure; confirm current standing with the state licensing board.
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
- (978) 537-3900
- Email not available
Practice Locations
479 OLD UNION TPKE
Lancaster, MA 01523
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
- Cataracts
- Diabetic retinopathy
- Dry eye
- Glaucoma
- Macular degeneration
Cornea and external eye
- Blepharitis
- Corneal abrasion
- Corneal ulcer
- Keratoconus
- Pink eye
- Pterygium
Eyelid and tear drainage
- Blocked tear duct
- Chalazion
- Drooping eyelid
Refractive and focusing
- Astigmatism
- Eye misalignment (strabismus)
- Farsightedness
- Lazy eye (amblyopia)
- Nearsightedness
- Presbyopia
Retina and vitreous
- Epiretinal membrane
- Retinal detachment
Eye injuries
- Foreign Object in Eye
Inflammation, neurologic, and orbit
- Thyroid eye disease
- Uveitis
Retina & vitreous
- Eye Floaters and Flashes
Procedures & services
Most searched procedures
- Cataract surgery
- Eye exam
- LASIK
- Retina surgery
Examination and imaging
- Corneal topography
- Fluorescein angiography
Cataract and lens
- Intraocular lens exchange
- YAG laser capsulotomy
Corneal procedures
- Amniotic Membrane Eye Graft
Eye diagnostics
- Optical Coherence Tomography Scan
Eye injuries
- Eye Scratch Laceration Repair
- Foreign Object Removal from Eye
Eyelid surgery
- Stye Removal
Eyelid, tear duct, and muscle
- Drooping-eyelid repair
- Entropion repair
- Eye-muscle surgery
- Eyelid surgery
- Tear-duct bypass surgery
Glaucoma
- Glaucoma drainage-device implantation
- Laser peripheral iridotomy
- Minimally invasive glaucoma surgery
- Selective laser trabeculoplasty
Laser eye surgery
- Laser Floater Removal
Laser procedures
- Laser Treatment for Retinal Tear
Laser vision correction
- SMILE Eye Surgery
Refractive surgery
- Clear Lens Exchange
- Implantable Contact Lenses
Tear duct & Orbit
- Orbital Decompression Surgery
- Tear Duct Plugs
Procedures Most Often Billed to Medicare
3,098 services · 2,247 patients · 21 distinct codes
| Procedure | Type | Code | Services | Compared with peers |
|---|---|---|---|---|
| Removal of cataract with insertion of prosthetic lens | Procedure | 66984 |
310 | More often than most peers in Ophthalmology |
| Insertion of drug delivery implant into tear duct of eye | Procedure | 68841 |
210 | More often than most peers in Ophthalmology |
| Closure of tear duct opening using plug | Procedure | 68761 |
102 | More often than most peers in Ophthalmology |
| Removal of recurring cataract in lens capsule using a laser | Procedure | 66821 |
64 | More often than most peers in Ophthalmology |
| Complex removal of cataract with insertion of prosthetic lens | Procedure | 66982 |
24 | As often as other peers in Ophthalmology |
| Transplantation of outer layer of corneal tissue | Procedure | 65756 |
11 | Less often than most peers in Ophthalmology |
| Ultrasound scan of cornea to determine thickness | Imaging | 76514 |
29 | As often as other peers in Ophthalmology |
| Measurement of corneal curvature and depth of eye | Treatment | 92136 |
605 | More than most peers in Ophthalmology |
| Imaging of retina | Treatment | 92134 |
235 | More often than most peers in Ophthalmology |
| Imaging of front third of eye using a special microscope | Treatment | 92286 |
190 | More 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 5
Same specialty, same street address — most likely the same department or group.
Related specialists at this location 8
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 — 23 related providers in 3 groups
Trained at University of Cincinnati College of Medicine 8
Other providers in the same specialty who trained at the same institution.
Class of 2004 at University of Cincinnati College of Medicine 7
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 MA who bill this service to Medicare most often.
Common questions
What kind of doctor is Joann CONG YIN Chang?
Joann CONG YIN Chang is an eye doctor in Lancaster, MA. That is the designation recorded for this NPI in the federal registry, where it is listed as “Ophthalmology”.
NPI registry
What is Joann CONG YIN Chang's address?
Joann CONG YIN Chang is listed at 479 Old Union Tpke, Lancaster, MA 01523. Addresses come from the NPI registry and can lag a move, so confirm before travelling.
NPI registry
How can I make an appointment with Joann CONG YIN Chang?
The number on file is (978) 537-3900. Guide.md cannot book appointments or pass on messages — please call the office directly.
NPI registry
What is Joann CONG YIN Chang's NPI number?
Joann CONG YIN Chang's National Provider Identifier is 1730359100. 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 Joann CONG YIN Chang train?
Joann CONG YIN Chang attended University of Cincinnati College of Medicine, graduating in 2004. This comes from the CMS National Downloadable File.
CMS public data
How long has Joann CONG YIN Chang been practicing?
Joann CONG YIN Chang has 22 years experience. Calculated from a graduation year of 2004, reported in the CMS National Downloadable File.
CMS public data
What procedures does Joann CONG YIN Chang perform?
According to Medicare billing data, Joann CONG YIN Chang performs procedures including removal of cataract with insertion of prosthetic lens, insertion of drug delivery implant into tear duct of eye and closure of tear duct opening using plug; reads or performs imaging such as ultrasound scan of cornea to determine thickness; provides treatments such as measurement of corneal curvature and depth of eye and imaging of retina, alongside routine visits and testing. This reflects Medicare patients only and is billing volume, not a measure of quality.
Medicare claims
Has Joann CONG YIN Chang confirmed this information?
Not yet. This profile is built from public federal data and has not been confirmed by Joann CONG YIN Chang. If this is you, claiming it is free.
Guide.md
Provider data sourced from the NPPES NPI Registry and CMS public datasets. Information is provided for reference and is not medical advice.