Purpose: To investigate the correlation between dose predicted by the treatment planning system (TPS) using either orthogonal digitally reconstructed radiographs (DRRs) or 3-D reconstructed CT images, and dose measured by semiconductor detectors, under clinical conditions of HDR brachytherapy of the cervix uteri.Materials and Methods: A total of 32 intracavitary brachytherapy applications were performed for 12 patients having cervix uteri cancer after receiving external pelvic irradiation with concomitant chemotherapy. The prescribed dose to point A was 7 Gy. Dose was calculated for both ICRU bladder and rectal points based on DRRs and for 3-D CT images based volumetric calculation of bladder and rectum. In vivo diode dosimetry was performed for the bladder and rectum during treatment sessions.Results: The ICRU bladder reference point received an average of 3.6 ± 0.9 Gy, while the volumes of 1, 2, and 5 cm3 of the bladder received 5.6 ± 2. Gy, 5.1 ± 1.7 Gy, 4.3 ± 1.4 Gy, respectively. The ratio of the 1 cm3 bladder dose to the diode dose was 1.8 ± 0.7, and the ratio of the dose at ICRU bladder reference point to the diode dose was 1.2 ± 0.5. The ICRU rectal reference point received an average of 5.1 ± 1.1 Gy, while the volumes of 1, 2, and 5 cm3 of the rectum received 5.3 ± 1.3 Gy, 4.9 ± 1.1 Gy, and 4.2 ± 0.9 Gy, respectively. The ratio of the 1 cm3 rectal dose to the diode dose was 1.9 ± 0.6, and the ratio of the ICRU rectal reference point dose to the diode dose was 1.8 ± 0.4.Conclusions: In HDR brachytherapy for cervix uteri cancer: 3-D image based dose calculation is the most accurate and reliable method to evaluate dose given to critical organs. ICRU bladder and rectal reference points are not good estimate of maximum dose given to these critical organs. In-vivo diode dosimetry is an important method of quality assurance, but clinical decision should be made based on 3-D calculations. Purpose: To investigate the correlation between dose predicted by the treatment planning system (TPS) using either orthogonal digitally reconstructed radiographs (DRRs) or 3-D reconstructed CT images, and dose measured by semiconductor detectors, under clinical conditions of HDR brachytherapy of the cervix uteri. Materials and Methods: A total of 32 intracavitary brachytherapy applications were performed for 12 patients having cervix uteri cancer after receiving external pelvic irradiation with concomitant chemotherapy. The prescribed dose to point A was 7 Gy. Dose was calculated for both ICRU bladder and rectal points based on DRRs and for 3-D CT images based volumetric calculation of bladder and rectum. In vivo diode dosimetry was performed for the bladder and rectum during treatment sessions. Results: The ICRU bladder reference point received an average of 3.6 ± 0.9 Gy, while the volumes of 1, 2, and 5 cm3 of the bladder received 5.6 ± 2. Gy, 5.1 ± 1.7 Gy, 4.3 ± 1.4 Gy, respectively. The ratio of the 1 cm3 bladder dose to the diode dose was 1.8 ± 0.7, and the ratio of the dose at ICRU bladder reference point to the diode dose was 1.2 ± 0.5. The ICRU rectal reference point received an average of 5.1 ± 1.1 Gy, while the volumes of 1, 2, and 5 cm3 of the rectum received 5.3 ± 1.3 Gy, 4.9 ± 1.1 Gy, and 4.2 ± 0.9 Gy, respectively. The ratio of the 1 cm3 rectal dose to the diode dose was 1.9 ± 0.6, and the ratio of the ICRU rectal reference point dose to the diode dose was 1.8 ± 0.4. Conclusions: In HDR brachytherapy for cervix uteri cancer: 3-D image based dose calculation is the most accurate and reliable method to evaluate dose given to critical organs. ICRU bladder and rectal reference points are not good estimate of maximum dose given to these critical organs. In-vivo diode dosimetry is an important method of quality assurance, but clinical decision should be made based on 3-D calculations.