Gonad shielding of children who undergo a pelvic examination may not be necessary if low-dose optimized digital radiography (DR) equipment is used, according to a new study by Dutch researchers published online first in Insights into Imaging.
If properly positioned, gonad shielding can lower radiation dose to the testes by about 95% and to the ovaries by about 50%, the study authors noted. However, the problem is that proper placement to cover the target area but none of the bony pelvic structures can be tricky, and it can result in retakes or suboptimal images that do not show all diagnostic images.
Radiologists at Maastricht University Medical Center believe that using gonad shielding may have more disadvantages than advantages. They compared 500 anterior-posterior (AP) pelvic radiographs taken in 2007 and 2008 using gonad shielding with 195 examinations taken in 2010 without gonad shielding. Their objective was to assess the quality of the images produced with respect to loss of diagnostic information and re-evaluate the benefit of shielding in terms of attainable radiation risk reduction (Insights into Imaging, 25 September 2011).
All the examinations for both time periods were performed using flat-panel DR systems (Axiom Aristos FX Plus, Siemens Healthcare). The systems had preprogrammed protocols, which set the high voltage (kVp), additional filter, focus to image-detector distance, and either a fixed tube current exposure (mAs) or the automatic exposure control (AEC). The protocols also indicated whether bucky antiscatter grids were needed. Age-dependent protocols with fixed technique parameters were used for children younger than age 10. Sized-based protocols were used for patients ages 10 to 15 years. The effective dose without gonad shielding ranged from 0.008 to 0.098 mSv.
The children ranged in age from infancy to 15 years. In 2007-2008, 61% of the patients imaged were girls, yet placement of shielding to protect the ovaries was incorrect in at least 87% of cases, the researchers found. For infants up to 12 months, an age group that represented almost one-third of the girls, shielding was properly placed only 3% of the time. Retakes had to be performed for more than half of the infant population, and retakes also had to be performed for 28% of patients ages 1 to 5 years (28% of the total of 304 female patients).
The percentage of improperly shielded testes was lower for boys, but still was quite high: a low of 52% for boys ages 1 to 5 years, representing 21% of the male group. It was highest at 71% for boys ages 5 to 10 years. However, only eight retakes were needed for this pediatric male group, seven of whom were for infants.
Based on the appearance of images when they were rereviewed, retakes had been performed only if they were of extremely poor quality and a diagnosis could not be made, according to lead author Dr. Marij Frantzen of the department of radiology. In one case in which a retake had been performed, a poorly positioned shield had covered an osteomyelitic lesion in a boy.
Gonad shielding was a necessity when radiation dose exposure for a pelvic AP exam was high. In the 1950s, it averaged about 10 mGy, but today the figure is a few tenths of a milligray. Staff at Maastricht decided in 2010 that it would be more beneficial to have images of constant good to excellent quality for all children rather than use gonad shielding with its inherent placement difficulties.
Without gonad shielding, the hereditary detriment adjusted risk for girls ranged between 0.1 x 10-6 and 1.3 x 10-6, and for boys between 0.3 x 10-6 and 3.9 x 10-6, depending upon their age. When shielding is properly positioned, the reduction in hereditary risk for girls was on average 6% of the total risk of the radiography and 24% for boys.
After making these calculations, Frantzen and colleagues still believed that the trade-off in increased radiation dose exposure to the testes and ovaries would be outweighed by having the peripheral zones of the pelvic bones displayed and providing images of excellent diagnostic quality to radiologists for interpretation. But it is imperative that clinical staff use state-of-technology, low-dose DR systems and protocols that adhere to the as low as reasonably achievable (ALARA) principles. Otherwise, they should continue to use gonad shielding with the realization that attention to placement is imperative, the authors noted.
![Examples of ultrasound findings and techniques. (A) Images in a 39-year-old male patient with a mass in the left thigh. The mass is heterogeneous on the B-mode US image (compared with the patient in D) and showed increased microvascularity (superb microvascular imaging [SMI]) and shear-wave elastography (SWE) values. Undifferentiated pleomorphic sarcoma was diagnosed at biopsy (with pleomorphic rhabdomyosarcoma in surgical specimen). (B) Images in an 18-year-old male patient with a mass in the left leg. The mass is hypoechoic on the B-mode image, with no other findings suggestive of malignancy. The lesion is in contact with the cortex of the tibia, which is slightly irregular. CT revealed a doubtful anteromedial tibial erosion. The microvascular study demonstrated high vascularization, suggestive of malignancy. Periosteal Ewing sarcoma was diagnosed with both histologic and immunohistochemical confirmation. (C) Images in a 69-year-old female patient with a lump growing on the outside of the left leg. Multiple SWE examinations were performed (please note the high values obtained in the measurements, whereas the color map highlights the stiffness relative to adjacent tissues). SMI showed areas of increased vascularization to target for sampling. Undifferentiated spindle cell sarcoma was diagnosed at biopsy, with residual leiomyosarcoma in the surgical specimen after neoadjuvant therapy. (D) Images in a 56-year-old female patient with a mass in the right thigh. The mass is heterogeneous at both B-mode ultrasound (similar to patient A) and MRI (coronal T2-weighted spectral attenuated inversion recovery [SPAIR]; T1-weighted pre-contrast and postcontrast imaging), which even shows uptake after the administration of paramagnetic contrast material, which is traditionally suggestive of malignancy. Low values at SMI and elastography are suggestive of benignity. Spindle cell lipoma was diagnosed at biopsy, with atypical spindle cell lipomatous tumor in the surgical specimen.](https://img.auntminnieeurope.com/mindful/smg/workspaces/default/uploads/2026/08/images-radiol250278fig2.APCFLSvX6p.jpg?auto=format%2Ccompress&fit=crop&h=100&q=70&w=100)
![Examples of ultrasound findings and techniques. (A) Images in a 39-year-old male patient with a mass in the left thigh. The mass is heterogeneous on the B-mode US image (compared with the patient in D) and showed increased microvascularity (superb microvascular imaging [SMI]) and shear-wave elastography (SWE) values. Undifferentiated pleomorphic sarcoma was diagnosed at biopsy (with pleomorphic rhabdomyosarcoma in surgical specimen). (B) Images in an 18-year-old male patient with a mass in the left leg. The mass is hypoechoic on the B-mode image, with no other findings suggestive of malignancy. The lesion is in contact with the cortex of the tibia, which is slightly irregular. CT revealed a doubtful anteromedial tibial erosion. The microvascular study demonstrated high vascularization, suggestive of malignancy. Periosteal Ewing sarcoma was diagnosed with both histologic and immunohistochemical confirmation. (C) Images in a 69-year-old female patient with a lump growing on the outside of the left leg. Multiple SWE examinations were performed (please note the high values obtained in the measurements, whereas the color map highlights the stiffness relative to adjacent tissues). SMI showed areas of increased vascularization to target for sampling. Undifferentiated spindle cell sarcoma was diagnosed at biopsy, with residual leiomyosarcoma in the surgical specimen after neoadjuvant therapy. (D) Images in a 56-year-old female patient with a mass in the right thigh. The mass is heterogeneous at both B-mode ultrasound (similar to patient A) and MRI (coronal T2-weighted spectral attenuated inversion recovery [SPAIR]; T1-weighted pre-contrast and postcontrast imaging), which even shows uptake after the administration of paramagnetic contrast material, which is traditionally suggestive of malignancy. Low values at SMI and elastography are suggestive of benignity. Spindle cell lipoma was diagnosed at biopsy, with atypical spindle cell lipomatous tumor in the surgical specimen.](https://img.auntminnieeurope.com/mindful/smg/workspaces/default/uploads/2026/08/images-radiol250278fig2.APCFLSvX6p.jpg?auto=format%2Ccompress&dpr=2&fit=crop&h=167&q=70&w=250)
