PDA-phone-based instant transmission of radiological images over a CDMA network by combining the PACS screen with a Bluetooth-interfaced local wireless link

Abstract

Remote teleconsultation by specialists is important for timely, correct, and specialized emergency surgical and medical decision making. In this paper, we designed a new personal digital assistant (PDA)-phone-based emergency teleradiology system by combining cellular communication with Bluetooth-interfaced local wireless links. The mobility and portability resulting from the use of PDAs and wireless communication can provide a more effective means of emergency teleconsultation without requiring the user to be limited to a fixed location. Moreover, it enables synchronized radiological image sharing between the attending physician in the emergency room and the remote specialist on picture archiving and communication system terminals without distorted image acquisition. To enable rapid and fine-quality radiological image transmission over a cellular network in a secure manner, progressive compression and security mechanisms have been incorporated. The proposed system is tested over a code division Multiple Access 1x-Evolution Data-Only network to evaluate the performance and to demonstrate the feasibility of this system in a real-world setting.

Fig 1.

A system configuration of PDA–phone-based emergency teleradiology system. PACS should be installed in the emergency room. Bluetooth and cellular communication link the PACS screen to both attending physician’s PDA and remote consultant’s PDA.

Fig 2.

Multiresolution image compression by two-stage application of JPEG progressive compression. (a) Original image 1,280 × 1,024 pixels. (b) Subsampled image (1/4) 320 × 256 pixels, first transmission. (c) Upsampled image 1,290 × 1,024 pixels. (d) Difference image (a)–(c) 1,280 × 1,024 pixels, second transmission (see the expanded Fig. 2d). (e) Last updated image 1,280 × 1,024 pixels.

Fig 3.

Secure wireless transmission of radiological image through Bluetooth with SAFER+ scheme and through CDMA 1×-EVDO with mobile VPN.

Fig 4.

Transmission time in terms of compression ratio. Total transmission time is affected by CDMA phone-calling setup time, first image transmission over Bluetooth, first image transmission over CDMA 1×-EVDO, second image transmission over Bluetooth, and second image transmission over CDMA 1×-EVDO.

Fig 5.

Regarding image distortion, the proposed system (b) is compared with the direct photographing method (c)–(g). (a) Original image. (b) Undistorted image acquisition. (c) Overexposed distortion. (d) Underexposed distortion. (e) Reflection distortion due to camera flash. (f) Camera-shaking distortion. (g) Unmatched camera focus distortion.

Fig 6.

Image-viewing functions including (a) full-screen display, (b) zoomed display, (c) rotated display, and (d) magnified display are implemented to display with different resolution, display format, and orientation.