Evaluation of aDigital Camera for

Acquiring Teleradiology Images

Elizabeth A. Krupinski, PhDUniversity of ArizonaDepartment of RadiologyArizona Telemedicine Program

Ronald S. Weinstein, MDUniversity of ArizonaDepartment of PathologyArizona Telemedicine Program

Carlos Gonzales, MD Michael GonzalesPatagonia Family Health Center

This work was supported by:

1) US Dept. Agriculture, Rural Utilities Service Distance Learning and Telemedicine Grant2) US Dept. Commerce, National Telecommunications and Information Administration TIIAP Grant3) Office of Rural Health Policy, HRSA Dept. Health & Human Services Rural Telemedicine Grant Program4) The State of Arizona

Goal To determine if a commercially available

digital camera can be used to acquire photographs of radiologic images to transmit them via store-forward technology over a telemedicine network.

ATP Telemedicine SitesTuba City

Kingman

Cottonwood

Ganado

Payson Springerville

Whiteriver

DOC - Phoenix

DOC - Yuma

NogalesPatagonia

Douglas

AHSCKinoTucson VA

AHSC Hub

Telemedicine

Telepathology

Teleradiology

Flagstaff

NARBHA Net

Arizona Rural Telemedicine Network (ARTN) ATM based network based on high-speed T1 carriers 3 ATM switches located in Northern (Flagstaff),

Central (Phoenix) & Southern (Tucson) regions of the state

Tandberg CANVAS Health Care Unit for real-time interactive teleconsults

MedVision for store-forward teleconsults CompuRAD/Lumisys for teleradiology

Case Volume Telemedicine

020406080

100120140160180

Num

ber

of C

ases

2ndQtr97

3rdQtr97

4thQtr97

1stQtr98

2ndQtr98

3rdQtr98

4thQtr98

1stQtr99

Teleradiology Network 3 of the sites (Kino Community

Hospital in Tucson, Springerville & White River) are connected to the University Medical Center via the high-speed (T1) Arizona Rural Telemedicine Network (ARTN)

1 site (Tucson VA) uses dial-up service

Case Volume Teleradiology

0

50

100

150

200

250

300

350N

umb

er o

f ca

ses

2ndQtr97

3rdQtr97

4thQtr97

1stQtr98

2ndQtr98

3rdQtr98

4thQtr98

1stQtr99

Sub-Specialties CoveredCardiology Ophthalmology Peds. Orthopedics

Dental Orthoped. Surg. Peds. Psychiatry

Dermatology Orthopedics Peds. Pulmonology

Endocrinology Otorhinology Peds. Rheumatology

Fam. & Comm. Med. Pain Clinic Peds. Urology

Gastroenterology Pathology Psychiatry

Genetics Peds. Cardiology Radiology

Hematology/OncologyPeds. Dermatology Reprod/Infertility

Infectious Disease Peds. Endocrinology Rheumatology

Internal Medicine Peds. Gastroenterology Surgery

Medicine Peds. Hem/Onc Surgical Oncology

Nephrology Peds. Infec. Disease Toxicology

Neurology Peds. Nephrology Urology

Ob/Gyn Peds. Neurology Vascular

Types of Service

Routine Diagnostic Consult

38%

Second Opinion18%

Medication Check19%

Psych Therapy15%

Other1%

Psych Evaluation6%

Manage Chronic Condition

2%

Manage Acute Condition

1%

Patient Information

Lab Reports51%

Written*10%

Still Photos23%

Other4%

EKG/EEG/EMG2%

Radiographs10%

Rationale Teleradiology is an important part of an

increasing number of Radiology & Telemedicine programs

Saves time and feedback to referring clinician is faster than with other methods (e.g., courier) - 85% of our teleradiology cases have a “wet read” report generated within 6 hours

Rationale

It can, however, be expensive! For digital modalities a merge box is needed For plain film a digitizer or video capture system

is required Some sites just cannot afford these options A low-cost alternative had to be explored

Rationale The Patagonia Family Health Center needs

consults especially in orthopedics & bone radiology

Have no x-ray facilities so send patients to Nogales’ Mariposa Clinic, the report & films are sent over either with patients or later

Problem - Mariposa only has a general radiologist so sub-specialty consults are often required

The Camera

Canon PowerShot600CCD image sensor832 x 608 pixels24-bit color resolutionf/2.5 lensBuilt-in flash150 kB file size

The Cases 40 bone trauma cases (e.g., fracture, subluxation,

soft tissue damage) from the Patagonia Family Health Clinic

Cases that required a consult in the past & were representative of the types of cases they would be sending for teleconsults in the future - typically subtle lesions

The Photographs Film images were placed on standard viewbox

with extraneous light blocked out The physician identified region(s) of interest

based on clinical history and nature of problem At least one global and one close up shot were

acquired for each image using the Canon PowerShot camera

Display

Images sent over ARTN to the MedVision workstation

Color monitor, 1024 x 768 pixels Window/level, zoom/pan available for use during

viewing Film images displayed on standard viewbox

Protocol 2 orthopedic surgeons & 2 bone radiologists

reviewed the 40 cases on film & using the digital photographs displayed on the monitor

Film reading 6 months after monitor reading Reported:

• Diagnosis• Decision confidence using 6-level scale• Image quality using 4-level scale

Results - Image Quality

0

1020

3040

50P

ER

CE

NT

Film Photo

Excellent

Good

Fair

Poor

Results - Image Quality 2 = 20.32, df = 9, p = 0.02 9 of the photo cases were rated poor

4 film cases were rated poor Of the 9 photo cases, 4 (45%) were rated as poor

because the region-of-interest was not captured sufficiently

Some views (film & photo) were not what the readers were used to - different technologists

Results - Diagnoses* Reader Agreement (Kappa)

1 0.89

2 0.92

3 0.94

4 0.88

* Truth was determined by 2 radiologists not participating in the study from the film images

Results - Confidence

0

20

40

60

PE

RC

EN

T

FILM vs PHOTOCONFIDENCE

Same*

One*

Two*

* How many categories film & monitor confidences differ by

Conclusions A digital still camera can be used effectively to

capture images of bone trauma radiographs for store-forward telemedicine consults

Well-framed close-up shots of the region-of-interest are essential

Good quality original films are essential

Other Applications? Other non-screening applications where a specific

suspicious region-of-interest can be identified for close-up photographs

Unless the lesion is fairly gross, the global shots are not adequate for consultation - close-up shots are required in the majority of cases