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The first stage of development of a series of mammo graphs was finished at ROENTGENPROM JSC in late 2008. These mammographs are designed to run all types of mammographic examinations. The serial production of these mammographs was started in 2008. This series includes the first modern domestic film mammograph Mammo R (Fig. 1).Experience of domestic physicians and foreign man ufacturers was taken into account during development of this model. As a result, the Mammo R mammograph meets the requirements for a modern mammographic system for both screening and diagnostic examination of women. The Mammo R mammograph consists of 100% domestic components.Therefore, the first stage of development of domestic mammographs is complete. The Mammo R mammo graph has been available to Russian medical organizations since late 2008. Digital mammographs and biopsy units for Mammo R mammographs were developed at ROENTGENPROM JSC during the second and the third stages of the process of development of these domestic mammographs.The second stage (late 2009) will bring either a digi tal unit to the film mammograph or a completely digital mammograph.Advantages of a digital mammograph over a film mammograph include the ability to take higher quality photographs at lower radiation dose. The mammograph This work describes specifications of a modern domestic film mammograph available from ROENTGENPROM JSC. Serial production of this mammograph began in 2008. This was the end of the first stage of development of a series of mammographs. The second stage included manufacture of the Mammo RPTs digital scanning mammo graph. This stage will be finished in late 2009. A biopsy unit compatible with this mammograph will be developed in 2010. New Devices Fig. 1. General view of the Mammo R mammograph.

The Ministry of Health of the Russian Federation has issued recommendations for methods of X ray radia tion dose control in roentgenology [3 11]. According to MUK 2.6.1.962 00 [11], effective radiation dose should be monitored during diagnosis and prophylaxis.MUK is intended to provide treatment and prophy laxis and organization of measurement of radiation doses received by patients. MUK is applicable to all types of medical X ray examinations, except mammography, com puter tomography, osteodensitometry, and dental X ray. MUK 2.6.1.962 00 determines two methods of meas urement of effective dose. The first method is based on measurement of the product of dose multiplied by area. Effective dose (D eff ) received by a patient of given age dur ing X ray examination is calculated from the equation:where Φ is the product of dose multiplied by area, cGy⋅cm 2 , and K d is dose coefficient for a given examina tion, µSv/(cGy⋅cm 2 ). The dose coefficient is equivalent to the ratio of effective dose to the input dose. An expensive instrument for measuring the product of dose multiplied by area is an obligatory component of medical X ray examination. According to the second method used in general roentgenoscopy and fluorogra phy, effective dose received by a patient of given age dur ing X ray examination is calculated from the equation:where R is radiation yield of X ray source, (mR⋅m 2 )/ (mA⋅sec); i is tube current, mA; t is examination time, sec; K e is dose coefficient for given examination, µSv/(mR⋅m 2 ). The dose coefficient is equivalent to ratio of effective dose to the radiation yield. Unfortunately, the second method is not applicable to digital X ray scanning radiography and fluorography because a fan shaped beam formed by a slot diaphragm is used in these cases [2]. In case of scanning X ray, effective exposure time t eff is introduced. This parameter depends on the slot width and rate of scanning.In addition, there are certain disadvantages of this method of measurement of effective dose. First, radiation yield of a radiation source is variable depending on anode exploitation time, filtration properties, etc. Therefore, radiation yield of an X ray radiation source should be controlled at least twice a year. Second, coefficient K e [11] was obtained statistically and cannot be applied to a given patient without correction.The goal of this work was to describe a method for determination of the effective dose received by a patient during digital scanning fluorographic examination from the results of measurement of radiation dose scattered by the patient's body.This method requires a special dosimeter of scat tered radiation. The theoretical advantages of the method are:1) detector location outside working beam and pos sibility of online measurement of exposure dose of scat tered radiation without distortion;2) dependence of measured exposure dose (calculat ed effective dose) on individual properties of the object (patient).