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James C Ahn, MD

Ophthalmology · Palo Alto

NPI 1902915028

Medicare standing
Clear
Enrolled, allowed to bill and order, not excluded
Plans that list them
1
1 carrier
Office
1

Offices

1 location · Sutter Bay Medical Foundation · 3,783 clinicians in this group

Looking this up.

Plans that list them

1 plan · 1 carrier

A missing listing does not mean out of network. Directories change, and a listing does not cover every office. Call Dr. Ahn’s office at (415) 600-1020 to confirm they take your plan. Ask about the office you use, its medical group, referrals and appointments.

Plans whose provider directory lists this clinician
DualConnect (HMO D-SNP)Santa Clara Family Health PlanListedSep 1, 2026

California Medical Board record

Licence G52250 · Current

Licensed to practise in California · since 1984 · expires 2028-02-29 · Boston University School of Medicine.

No disciplinary actions, convictions, malpractice judgments or citations in this record.

Original Medicare doctor bills

$34,956

Medicare paid this office $34,956 for 124 people.

This is what Medicare paid the clinician — not Medicare Advantage, and not the pharmacy.

Largest Original Medicare bills
Return visit (30+ min)76$9,892$116
Long return visit (40+ min)20$3,820$166
Short return visit (20+ min)20$1,612$73
Exam to measure eye deviation and range of motion21$1,560$60
Imaging of optic nerve38$1,444$36
See all 6 services
Every Original Medicare service billed
Return visit (30+ min)76$9,892$116
Long return visit (40+ min)20$3,820$166
Short return visit (20+ min)20$1,612$73
Exam to measure eye deviation and range of motion21$1,560$60
Imaging of optic nerve38$1,444$36
Exam of visual field with extended testing15$977$61

Who their Medicare patients are

124 Original Medicare patients in 2024. Average age 77 · Women 65% · Health risk score 0.84. At or below the middle of the specialty; the typical ophthalmology clinician is at 1.16.

Conditions among them: High blood pressure 53% · Diabetes 21% · Coronary heart disease 19% · Cancer 16% · Atrial fibrillation 15% · Depression 15% · Chronic kidney disease 10% · Stroke 9%.

The office billed $138,406, Medicare allowed $46,358 and paid $34,956; for 1,873 services of 21 kinds.

Original Medicare patients only. A risk score of 1.0 is the average Medicare patient; higher means sicker. Any count under 11 is hidden.

Year by year

Original Medicare by year
20241241,873770.84$138,406$34,956
20231311,491750.90$141,931$35,010
20221531,299750.87$147,468$39,373
2021131821770.95$109,795$28,818
20201821,050751.01$170,906$42,480
20192921,850761.01$352,558$81,348
20183291,548760.94$364,772$87,627
20173291,366760.91$393,331$92,973
20163351,337751.04$399,089$94,850
20153971,797760.99$494,351$124,301
20143611,905750.96$465,694$108,500
20133031,571741.12$313,175$77,212

Original Medicare only. A service billed for fewer than 11 people in a year is hidden, so the lines can add up to less than the year's total.

See the services billed each year

2023: 5 services

Original Medicare services billed in 2023
Return visit (30+ min)78$9,268$107
Long return visit (40+ min)17$3,487$174
Short return visit (20+ min)22$2,128$82
Exam of visual field with extended testing30$1,909$58
Imaging of optic nerve31$1,217$36

2022: 6 services

Original Medicare services billed in 2022
Return visit (30+ min)93$12,167$110
Short return visit (20+ min)40$4,893$84
Long return visit (40+ min)18$3,146$175
Exam to measure eye deviation and range of motion34$2,777$60
Imaging of optic nerve35$1,437$36
Exam of visual field with extended testing20$1,184$51

2021: 6 services

Original Medicare services billed in 2021
Return visit (30+ min)74$8,891$107
Short return visit (20+ min)30$3,226$83
Exam of visual field with extended testing36$2,355$60
Long return visit (40+ min)13$1,967$151
Exam to measure eye deviation and range of motion24$1,551$60
Imaging of optic nerve24$879$34

2020: 6 services

Original Medicare services billed in 2020
Return visit (30+ min)109$12,256$94
Short return visit (20+ min)39$3,064$65
Long return visit (40+ min)20$3,029$138
Exam to measure eye deviation and range of motion28$2,494$64
Exam of visual field with extended testing36$2,083$56
Imaging of optic nerve45$1,688$34

2019: 14 services

Original Medicare services billed in 2019
Return visit (30+ min)170$20,595$98
Repair of tendon of upper eyelid15$12,663$844
Short return visit (20+ min)79$7,293$68
Botox12$5,368None
Exam to measure eye deviation and range of motion44$4,178$61
Face injection for nerve paralysis12$3,920$145
Exam of visual field with extended testing49$2,903$57
New patient visit (45+ min)16$2,290$143
Imaging of optic nerve57$2,212$35
Biopsy of eyelid12$2,177$181
Long return visit (40+ min)13$1,607$124
New patient visit (30+ min)16$1,351$84
Short return visit14$670$37
Office for the evaluation and management of established patient that may not require presence of healthcare professional12$326$19

2018: 11 services

Original Medicare services billed in 2018
Return visit (30+ min)203$24,162$94
Repair of tendon of upper eyelid13$9,919$763
Short return visit (20+ min)81$7,216$62
Exam of visual field with extended testing68$4,521$58
Exam to measure eye deviation and range of motion58$4,333$64
Long return visit (40+ min)26$3,658$131
Probing of nasal tear duct18$3,054$153
Imaging of optic nerve57$2,302$35
New patient visit (30+ min)21$2,026$96
New patient visit (45+ min)16$1,925$120
Short return visit16$767$40

2017: 14 services

Original Medicare services billed in 2017
Return visit (30+ min)219$26,402$92
Repair of tendon of upper eyelid19$15,078$794
Short return visit (20+ min)76$6,608$65
Exam to measure eye deviation and range of motion62$5,523$60
Exam of visual field with extended testing68$3,997$57
Long return visit (40+ min)21$3,499$135
Biopsy of eyelid22$3,456$157
Probing of nasal tear duct14$2,503$132
Imaging of optic nerve61$2,462$34
New patient visit (45+ min)16$2,423$151
New patient visit (30+ min)21$1,850$88
Dilation of tear drainage opening11$1,186$99
Short return visit17$627$35
Office for the evaluation and management of established patient that may not require presence of healthcare professional13$321$19

2016: 15 services

Original Medicare services billed in 2016
Return visit (30+ min)142$17,606$98
Repair of tendon of upper eyelid17$13,165$731
Removal of growth of eyelid26$7,773$268
Short return visit (20+ min)78$6,766$67
Established patient problem focused exam of visual system77$6,153$71
Exam to measure eye deviation and range of motion56$4,439$60
Exam of visual field with extended testing70$3,827$51
Biopsy of eyelid18$2,740$152
Imaging of optic nerve54$2,506$41
Established patient complete exam of visual system23$2,316$101
New patient visit (45+ min)14$2,128$152
Dilation of tear drainage opening12$1,602$107
Short return visit30$1,385$38
New patient visit (30+ min)15$1,340$89
Office for the evaluation and management of established patient that may not require presence of healthcare professional16$275$17

2015: 19 services

Original Medicare services billed in 2015
Return visit (30+ min)174$23,014$100
Repair of tendon of upper eyelid14$11,275$805
Established patient problem focused exam of visual system98$9,544$80
Removal of growth of eyelid26$7,443$266
Exam to measure eye deviation and range of motion69$7,155$66
Extensive repair of turning-outward eyelid defect13$6,490$499
Exam of visual field with extended testing80$6,007$64
Established patient complete exam of visual system47$5,484$114
Short return visit (20+ min)67$5,166$67
Dilation of tear drainage opening27$4,331$124
Imaging of optic nerve70$3,593$43
New patient visit (45+ min)22$3,364$153
Long return visit (40+ min)19$3,177$138
Short return visit41$1,908$40
New patient complete exam of visual system12$1,527$127
New patient problem focused exam of visual system11$748$68
Exam of visual field with limited testing14$471$34
Photography of content of eyes16$337$20
Office for the evaluation and management of established patient that may not require presence of healthcare professional12$247$21

2014: 17 services

Original Medicare services billed in 2014
Repair of tendon of upper eyelid26$21,028$779
Return visit (30+ min)81$8,312$89
Established patient problem focused exam of visual system83$8,092$82
Established patient complete exam of visual system66$7,641$108
Dilation of tear drainage opening45$7,582$108
Short return visit (20+ min)96$6,712$60
Removal of growth of eyelid16$4,516$266
Exam of visual field with extended testing59$4,032$58
Short return visit49$2,449$39
Imaging of optic nerve39$1,933$41
Biopsy of eyelid12$1,814$151
Exam to measure eye deviation and range of motion23$1,705$63
Long return visit (40+ min)13$1,672$105
New patient visit (45+ min)11$1,554$141
New patient complete exam of visual system11$1,250$114
Photography of content of eyes44$872$20
Exam of visual field with limited testing11$367$33

2013: 13 services

Original Medicare services billed in 2013
Return visit (30+ min)143$15,306$92
Short return visit (20+ min)88$5,744$59
Dilation of tear drainage opening28$4,811$107
Removal of growth of eyelid16$4,659$259
Established patient complete exam of visual system36$4,033$106
Long return visit (40+ min)25$3,333$128
Exam of visual field with extended testing45$3,205$59
Exam to measure eye deviation and range of motion30$1,940$54
Imaging of optic nerve36$1,866$41
Short return visit26$1,215$35
Established patient problem focused exam of visual system11$921$84
Exam of visual field with limited testing26$920$33
Photography of content of eyes29$581$20

Drugs they prescribed that Part D paid

$18,910

Pharmacies billed $18,910 in 2024.

This is pharmacy cost, not the office bill, and not what patients paid.

Opioids were 0% of their Part D prescriptions (0 of 60) in 2024. At or below the middle of the specialty; the typical ophthalmology clinician is at 0%.

31 generic and 29 brand-name prescriptions · $18,910 in drug cost.

Part D prescriptions only. The opioid rate is opioid prescriptions as a share of all this clinician's Part D prescriptions; surgeons and pain specialists run higher than others, so it is shown against the same specialty.

Largest Part D drug costs
Latanoprost15$132$9

Year by year

Part D prescribing by year
202460250% (0)48%$18,910
202352150% (0)46%$9,468
202262230% (0)47%$11,759
202151320% (0)47%$11,044
202012160None50%$16,284
201918377None51%$12,461
2018202800% (0)44%$13,995
2017227980% (0)39%$15,088
201621279None47%$13,352
201528296None41%$18,804
201414659None37%$7,322
2013107440% (0)50%$7,442

Part D prescriptions only. A drug prescribed to fewer than 11 people in a year is hidden.

See the drugs prescribed each year

2023: 1 drug

Part D drugs prescribed in 2023
Timolol Maleate12$159$13

2022: 1 drug

Part D drugs prescribed in 2022
Latanoprost12$284$24

2020: 4 drugs

Part D drugs prescribed in 2020
Latanoprost30$951$32
Olopatadine15$501$33
Erythromycin11$123$11
Polymyxin B Sul-Trimethoprim13$101$8

2019: 5 drugs

Part D drugs prescribed in 2019
Brimonidine12$2,108$176
Olopatadine22$1,478$67
Latanoprost63$1,397$22
Erythromycin21$239$11
Polymyxin B Sul-Trimethoprim12$101$8

2018: 5 drugs

Part D drugs prescribed in 2018
Timolol Maleate16$1,679$105
Olopatadine25$1,205$48
Tobramycin-Dexamethasone13$990$76
Latanoprost47$783$17
Polymyxin B Sul-Trimethoprim17$158$9

2017: 5 drugs

Part D drugs prescribed in 2017
Pataday11$1,826$166
Olopatadine13$1,388$107
Latanoprost47$1,085$23
Polymyxin B Sul-Trimethoprim36$305$8
Diclofenac13$299$23

2016: 6 drugs

Part D drugs prescribed in 2016
Pataday11$1,751$159
Brimonidine19$1,410$74
Azelastine24$794$33
Latanoprost55$702$13
Dorzolamide-Timolol12$212$18
Polymyxin B Sul-Trimethoprim13$109$8

2015: 7 drugs

Part D drugs prescribed in 2015
Brimonidine30$3,201$107
Pataday13$1,974$152
Tobramycin-Dexamethasone12$1,424$119
Latanoprost78$931$12
Timolol Maleate11$471$43
Erythromycin21$250$12
Polymyxin B Sul-Trimethoprim24$201$8

2014: 4 drugs

Part D drugs prescribed in 2014
Latanoprost36$568$16
Timolol Maleate18$212$12
Erythromycin16$201$13
Polymyxin B Sul-Trimethoprim19$185$10

2013: 3 drugs

Part D drugs prescribed in 2013
Pataday11$1,371$125
Timolol Maleate16$240$15
Latanoprost15$220$15

Professional record

NPI
1902915028
Licence
CA G52250California G52250: Current · expires 2028-02-29
Trained
Boston University School of Medicine, 1982
Gender
Male
More record details
Sole proprietor
No
Taxonomy
Federal specialty code 207W00000X (207W00000X)
Mailing address
325 Distel Cir, Los Altos, CA, 94022
NPI first listed
2006-08-30
NPI last updated
2020-03-03
NPI record certified
2020-03-03

This is when the NPI record was last certified, not a medical board exam.