Problems with film processing in medical X-ray imaging in Lithuania.

Optimisation in X-ray imaging in order to reduce patient doses during diagnostic X-ray examinations is a complex process given the high level of image quality required. When quality systems are implemented as a basis for optimisation, attention should be paid to the qualifications of the staff and quality control of the equipment and of the X-ray imaging procedures, as well as to the methods used to evaluate the quality of these procedures. Until recently, quality control procedures at health care institutions in Lithuania were limited to the testing of X-ray units. Since film processing is one of the most important factors influencing patient doses and image quality during X-ray examinations, in 2003 the Kaunas department of the Radiation Protection Centre organised inspections of film processing laboratories in 11 health care institutions-hospitals and outpatient departments-in the Kaunas region. Problems of non-compliance with requirements identified during these inspections are discussed in this paper. Most of the health care institutions inspected already had quality assurance programmes. However, the implementation of these programmes was sometimes erratic because of the insufficient attention paid to the film developing processes. The worst situation was found in 4 institutions where the films were developed manually. Only 3 of the 11 departments inspected had sensitometers and densitometers for quality control of the processing. In many cases there was no control of chemicals, film sensitivity and density, or else control was irregular. In only a few departments were the effects of repeated controls investigated and discussed. Despite the current problems occurring in medical X-ray diagnostic departments in Lithuania, the situation is rapidly improving. New equipment is being installed, new devices for quality control are being used and, last but not least, the view of hospital administrators, radiologists and laboratory workers towards quality assurance and quality control is changing.

Comparison of implant quality between loose and intra-operatively linked iodine-125 seeds in prostate cancer brachytherapy.

From 2007 to 2010, 230 patients had iodine-125 seeds implanted (loose or intra-operatively linked into seed trains with variable seed-to-seed spacing). The primary aim was to evaluate differences in implant quality by comparing the intra-operative and post-implant dosimetry in patients treated with loose and intra-operatively linked seeds. The secondary aim was to evaluate the "learning curve" for the procedure. The following parameters were compared: the radiation dose to 90% of the prostate volume (D90), the radiation dose to 30% of the urethral volume (DU30), the percentage of the prostate volume receiving 100% or 200% of the prescribed dose (V100 or V200, respectively), the percentage of the rectal volume receiving 100% of the prescribed dose (VR100), and the homogeneity index (HI). We obtained the following results for loose vs. intra-operatively linked seeds: D90 (Gy), 184.7 ± 15.0 vs. 177.9 ± 12.7 (p = 0.002); V100 (%), 95.5 ± 2.4 vs. 94.9 ± 3.2 (p = 0.206); V200 (%), 35.1 ± 7.5 vs. 24.3 plusmn; 6,9 (p < 0.001); DU30 (Gy), 218.6 ± 24.1 vs. 197.4 ± 19.5 (p = 0.001); VR100 (cm³), 0.6 ± 0.47 vs. 0.3 ± 0.3 (p < 0.001); HI (%), 31.8 ± 7.3 vs. 44.0 ± 9.8 (p < 0.001). The advantages of intra-operatively linked seed implantation over loose seed implantation are a more homogeneous prostate dose and lower urethral and rectal doses. The disadvantage is a lower post-implant D90. Sufficient experience with the loose seed implantation procedure was obtained after the first 40 patients. There was essentially no learning curve when a new implantation method using intra-operatively linked seeds was subsequently initiated.