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DTS 5.1 and DFS
Clinical Radiology (2002) 57: 861±866 doi:10.1053/crad.2002.1084, available online at http://www.idealibrary.com on
Correspondence DTS 5.1 AND DFS Barium enema by a junior specialist registrar: are the doses to patients acceptable? SIR, During my ®rst year of radiology training I documented the dose area product (DAP) after each barium enema that I performed on a digital ¯uoroscopy system (DFS) (GE System 1694D, Prestalix, with Last Image Hold and ¯uoro store facility) and a non-digital (Diagnost 88, Philips, Conventional Image Intensi®er screening system, no last image or Fluoro store hold facility). The aim was to audit my performance with the dose reference level (DRL third centile of 3200 cGycm2) obtained from barium enemas ( patient's body weight 50±90 kg) performed by colleagues in the same department [1]. Doses from the decubitus radiographs were not included. Out of 32 eligible patients (body weight 50±90 kg) twenty four (75%, 95% CI 60±90%) recorded a DAP less than 3200 cGycm2. I ( just) achieved the standard set in the audit. The mean DAP from the non-digital and digital systems did not show a signi®cant dierence (2680 and 2600 cGycm2 respectively, P 0.8). The mean ¯uoroscopy time using the digital system was 53% less than that in the non-digital system (2.3 versus 4.9 minutes, P 0.000, the high outlier was excluded from the analysis). There was no signi®cant dierence in the DAP between the two systems from this study. However the dierence in ¯uoroscopy times was signi®cant. The reference DAP in `Clinical Audit in Radiology 100 Recipes' [2] is higher than the most recent DRL from the NRPB (6093 versus 3500c Gycm2) [3,4]. This probably re¯ects lower radiation exposures due to increasing use of digital ¯uoroscopy equipment kits in the past 5 to 10 years. This is the era of the Digital Tracking System - DTS 5.1 [5]. One would assume that most of us use a digital system (both for music and barium work) these days. But if you are one of those who use a nondigital system (and cherishes the old vinyl record) you may wish to upgrade to a state of the art pulsed ¯uoroscopy digital system. A. DOSS
Fig. ± Fluroscopy times from the non-digital system (1) are nearly twice as long as those of the digital system (2).
Diagnostic Radiology, Royal Hallamshire Hospital, Sheeld Teaching Hospitals NHS Trust, Sheeld S10 2JF, U.K.
REFERENCES 1 Doss A, Morrison G, Clout C, Collins MC. Barium Enemas by a Junior Radiologist in Training: Are radiation doses acceptable? Radiology (RSNA) 2001. Abstract p625. 2 Godwin R, de Lacey G, Manhire A. Clinical Audit in Radiology 100 Recipes. Royal College of Radiologists: London, UK 1996. 3 Hart D, et al. Doses to Patients from Medical X-ray Examinations in the UK -1995 Review. NRPB R289, 1996. 4 Diagnostic Reference Level Working Party. National Dose Reference Levels. January 2000. 5 DTS Digital Surround http://timefordvd.com/ref/dts.shtml.
0009-9260/02/$35.00
# 2002 The Royal College of Radiologists
Correspondence DTS 5.1 AND DFS Barium enema by a junior specialist registrar: are the doses to patients acceptable? SIR, During my ®rst year of radiology training I documented the dose area product (DAP) after each barium enema that I performed on a digital ¯uoroscopy system (DFS) (GE System 1694D, Prestalix, with Last Image Hold and ¯uoro store facility) and a non-digital (Diagnost 88, Philips, Conventional Image Intensi®er screening system, no last image or Fluoro store hold facility). The aim was to audit my performance with the dose reference level (DRL third centile of 3200 cGycm2) obtained from barium enemas ( patient's body weight 50±90 kg) performed by colleagues in the same department [1]. Doses from the decubitus radiographs were not included. Out of 32 eligible patients (body weight 50±90 kg) twenty four (75%, 95% CI 60±90%) recorded a DAP less than 3200 cGycm2. I ( just) achieved the standard set in the audit. The mean DAP from the non-digital and digital systems did not show a signi®cant dierence (2680 and 2600 cGycm2 respectively, P 0.8). The mean ¯uoroscopy time using the digital system was 53% less than that in the non-digital system (2.3 versus 4.9 minutes, P 0.000, the high outlier was excluded from the analysis). There was no signi®cant dierence in the DAP between the two systems from this study. However the dierence in ¯uoroscopy times was signi®cant. The reference DAP in `Clinical Audit in Radiology 100 Recipes' [2] is higher than the most recent DRL from the NRPB (6093 versus 3500c Gycm2) [3,4]. This probably re¯ects lower radiation exposures due to increasing use of digital ¯uoroscopy equipment kits in the past 5 to 10 years. This is the era of the Digital Tracking System - DTS 5.1 [5]. One would assume that most of us use a digital system (both for music and barium work) these days. But if you are one of those who use a nondigital system (and cherishes the old vinyl record) you may wish to upgrade to a state of the art pulsed ¯uoroscopy digital system. A. DOSS
Fig. ± Fluroscopy times from the non-digital system (1) are nearly twice as long as those of the digital system (2).
Diagnostic Radiology, Royal Hallamshire Hospital, Sheeld Teaching Hospitals NHS Trust, Sheeld S10 2JF, U.K.
REFERENCES 1 Doss A, Morrison G, Clout C, Collins MC. Barium Enemas by a Junior Radiologist in Training: Are radiation doses acceptable? Radiology (RSNA) 2001. Abstract p625. 2 Godwin R, de Lacey G, Manhire A. Clinical Audit in Radiology 100 Recipes. Royal College of Radiologists: London, UK 1996. 3 Hart D, et al. Doses to Patients from Medical X-ray Examinations in the UK -1995 Review. NRPB R289, 1996. 4 Diagnostic Reference Level Working Party. National Dose Reference Levels. January 2000. 5 DTS Digital Surround http://timefordvd.com/ref/dts.shtml.
0009-9260/02/$35.00
# 2002 The Royal College of Radiologists