. 2021 Dec 10;63(1):e12305. doi: 10.1002/1348-9585.12305

TABLE 4.

Eye lens dose reduction rate in radiation protection measures and number of possible annual radiology practices by clinical department

Physician	Number of radiology practice	H_p(3)_procedure (μSv/procedure)		DRR ^c [%]	Number of possible annual radiology practices
Physician	FY2018	H_p(3)_{procedure before} ^a	H_p(3)_{procedure after} ^b	DRR ^c [%]	Before‐measures ^d	After‐measures ^e
Cardiologist A	421	79.6	46.0	42	251	435
Cardiologist B	26	176.3	82.3	53	113	243
Cardiologist C	154	207.7	43.2	79	96	463
Neurosurgeon D	120	126.0	79.0	37	159	253
Neurosurgeon E	120	21.6	10.2	53	925	1961
Gastroenterologist F	397	51.1	21.1	59	392	946
Gastroenterologist G	40	24.8	13.5	45	807	1479
Gastroenterologist H	70	1.0	N/A ^f	—	20 000	—
Gastroenterologist I	111	24.9	15.3	39	803	1307
Gastroenterologist J	304	11.7	6.4	46	1705	3145
Orthopedic Surgeon K	97	8.8	2.0	78	2273	10 187
Orthopedic Surgeon L	Unknown	19.1	7.3	62	1045	2755
Radiologist N	202	87.8	28.4	68	228	704
Radiologist O	222	8.8	5.2	41	2268	3854

Number of radiology practice FY2018 > number of possible radiology practices per year are set in boldface; FY2018 = fiscal year 2018; DRR = dose reduction rate.

^{^a}

The median value of eye lens dose before radiation protection measures.

^{^b}

The median value of eye lens dose after radiation protection measures.

^{^c}

The dose‐reduction rate (DRR) [%] = (1 − b/a) 100.

^{^d}

Number of possible annual radiology practices (before radiation protection measures) = The equivalent dose limits to the lens of the eye (ICRP: average annual limit, 20 mSv/year over 5 years) /a.

^{^e}

Number of possible annual radiology practices (after radiation protection measures) = The equivalent dose limits to the lens of the eye (ICRP: average annual limit, 20 mSv/year over 5 years)/b.

^{^f}

Less than the lower limit of dose measurement.