Dose Reduction Protocol for Full Spine X-ray Examination Using Copper Filters in Patients With Adolescent Idiopathic Scoliosis

The Prevalence of Cancer in Dutch Female Patients with Idiopathic Scoliosis Compared with the General Population

Background and Objectives: Epidemiological studies have demonstrated the potential oncogenic effects of cumulative radiation exposure, particularly during childhood. One group experiencing repeated exposure to radiation at an early age for multiple years is patients treated for idiopathic scoliosis (IS). This study aimed to determine the relationship between childhood radiological exposure and adult cancer prevalence in children treated for IS. Materials and Methods: Data from 337 predominantly female patients treated at our hospital between January 1981 and January 1995 were gathered and compared to the Dutch national cancer rates. The standardized prevalence ratios for cancer in IS patients were compared with the cancer prevalence rates from the general Dutch population. Results: The overall cancer prevalence in women was 5.0%, with no significant difference compared to the general population (p = 0.425). The results of this study do not suggest that female patients treated for idiopathic scoliosis during childhood have an increased risk of cancer later in life. Conclusion: Despite being the largest recent study in its field, the modest participant number limits its ability to draw conclusions. However, the detailed data collected over a long observation period, alongside data from a period with comparable radiation rates, contributes to refining clinical practice and laying the groundwork for future systematic reviews.

Low-dose whole-spine imaging using slot-scan digital radiography: a phantom study

BACKGROUND

Slot-scan digital radiography (SSDR) is equipped with detachable scatter grids and a variable copper filter. In this study, this function was used to obtain parameters for low-dose imaging for whole-spine imaging.

METHODS

With the scatter grid removed and the beam-hardening (BH) filters (0.0, 0.1, 0.2, or 0.3 mm) inserted, the tube voltage (80, 90, 100, 110, or 120 kV) and the exposure time were adjusted to 20 different parameters that produce equivalent image quality. Slot-scan radiographs of an acrylic phantom were acquired with the set parameters, and the optimal parameters (four types) for each filter were determined using the figure of merit. For the four types of parameters obtained in the previous section, SSDR was performed on whole-spine phantoms by varying the tube current, and the parameter with the lowest radiation dose was determined by visual evaluation.

RESULTS

The parameters for each filter according to the FOM results were 90 kV, 400 mA, and 2.8 ms for 0.0 mm thickness; 100 kV, 400 mA, and 2.0 ms for 0.1 mm thickness; 100 kV, 400 mA, and 2.8 ms for 0.2 mm thickness; and 110 kV, 400 mA, and 2.2 ms for 0.3 mm thickness. Visual evaluation of the varying tube currents was performed using these four parameters when the BH filter thicknesses were 0.0, 0.1, 0.2, and 0.3 mm. The entrance surface dose was 59.44 µGy at 90 kV, 125 mA, and 2.8 ms; 57.39 µGy at 100 kV, 250 mA, and 2.0 ms; 46.89 µGy at 100 kV, 250 mA, and 2.8 ms; and 39.48 µGy at 110 kV, 250 mA, and 2.2 ms, indicating that the 0.3-mm BH filter was associated with the minimum dose.

CONCLUSION

Whole-spine SSDR could reduce the dose by 79% while maintaining the image quality.

Reduction of radiation exposure in scoliosis monitoring using flat detector and pulsed fluoroscopy technology

A new flat detector and pulsed fluoroscopy technology is available to further reduce radiation exposure in radiological monitoring during scoliosis treatment in children and adolescents. The aim of this study is to compare different settings of the system (opening area(OA) and image quality settings (IQS)) in order to find the optimal parameters with high image quality and the lowest possible radiation exposure. Therefore, we examined four cadaver spines (T1 to sacrum) with the flat detector technique using digital pulsed fluoroscopy and simulated the abdominal soft tissues. The images were merged and evaluated by three different investigators using an established scoring system. For comparison, we used digital radiography images of the cadaver spines. The values for the DAP increased from the small OA (33% ; 0.56 µGy·m²) to the maximum OA (100% ; 0.82 µGy·m²) by 45% (p = .003) and from the low image quality setting (0.57 µGy·m²) to the high setting (0.84 µGy·m²) by 48% (p = .028). Despite the low DAP, the setting 33% OA achieved the best point values for image quality, therefore this setting is clearly preferred. Using a digital fluoroscopy system allows a significant reduction of radiation exposure by a factor of 7.5 (3.88µGy·m² to 0.5µGy·m²) compared to slot- scanning x-ray (EOS). Due to this success, the flat detector and pulsed fluoroscopy technology can be an alternative to established methods such as X-ray and EOS in clinical use.

Combination of Side-Bending and Traction Radiographs Do Not Influence Selection of Fusion Levels Compared to Either One Alone in Adolescent Idiopathic Scoliosis

STUDY DESIGN

A retrospective study.

OBJECTIVES

Curve flexibility in patients with adolescent idiopathic scoliosis (AIS) can be evaluated using different techniques. This study aimed to determine whether the combination of side-bending (SB) and traction (TX) radiographs influences preoperative planning for AIS than either radiograph alone.

METHODS

Thirty-two spine surgeons were asked to review 30 AIS Lenke type 1 cases and select an upper instrumented vertebra (UIV) and lower instrumented vertebra (LIV) for the posterior spinal instrumentation of each case. Each rater reviewed the cases 3 times in each round. The raters were provided with the full-length posteroanterior (PA) and lateral standing and SB radiographs for round 1; PA, lateral, and TX radiographs for round 2; and PA, lateral, SB, and TX radiographs for round 3. Intra- and inter-rater reliabilities were evaluated using Kappa statistics.

RESULTS

The intra-rater reliability for UIV and LIV was 0.657 and 0.612 between rounds 1 and 2, 0.634 and 0.692 between rounds 1 and 3, and 0.659 and 0.638 between rounds 2 and 3, respectively, which indicated substantial agreement between rounds. The inter-rater kappa reliabilities for UIV and LIV selection were 0.103 and 0.412 for round 1, 0.121 and 0.380 for round 2, and 0.125 and 0.368 for round 3, indicating slight to moderate agreement between raters.

CONCLUSIONS

Whether raters used either SB or TX radiography, or both in addition to PA and lateral standing radiographs, did not influence the decision making for UIV or LIV of AIS Lenke type 1 surgery.

Using a dedicated spine radiology technologist is associated with reduced fluoroscopy time, radiation dose, and surgical time in pediatric spinal deformity surgery

STUDY DESIGN

Retrospective comparative study OBJECTIVES: The goal of this study was to investigate fluoroscopy time and radiation exposure during pediatric spine surgery using a dedicated radiology technologist with extensive experience in spine operating rooms. Repetitive use of intraoperative fluoroscopy during posterior spinal fusion (PSF) exposes the patient, surgeon, and staff to radiation.

METHODS

Retrospective review was conducted on patients with posterior spinal fusion (PSF) of ≥ 7 levels for adolescent idiopathic scoliosis (AIS) at a pediatric hospital from 2015 to 2019. Cases covered by the dedicated radiology technologist (dedicated group) were compared to all other cases (non-dedicated group). Surgical and radiologic variables were compared between groups.

RESULTS

230 patients were included. 112/230 (49%) were in the dedicated group and 118/230 (51%) were in the non-dedicated group. Total fluoroscopy time was significantly reduced in cases with the dedicated technologist (46 s) compared to those without (69 s) (p = 0.001). Radiation dose area product (DAP) and air kerma (AK) were reduced by 43% (p < 0.001) and 42% (p < 0.001) in the dedicated group, respectively. The dedicated group also had reduced total surgical time (4.1 vs. 3.5 h; p < 0.001) and estimated blood loss (447 vs. 378 cc (; p = 0.02). Multivariate regression revealed that using a dedicated radiology technologist was independently associated with decreased fluoroscopy time (p = 0.001), DAP (p < 0.001), AK (p < 0.001), surgical time (p < 0.001), and EBL (p = 0.02).

CONCLUSIONS

In AIS patients undergoing PSF, using a dedicated radiology technologist was independently associated with significant reductions in fluoroscopy time, radiation exposure, surgical time, and EBL. This adds to the growing body of research demonstrating that the experience level of the team-not just that of the surgeon-is necessary for optimal outcomes.

LEVEL OF EVIDENCE

III.

Decreased Vertical Trunk Inclination Angle and Pelvic Inclination as the Result of Mid-High-Heeled Footwear on Static Posture Parameters in Asymptomatic Young Adult Women

The influence of high-heel footwear on the lumbar lordosis angle, anterior pelvic tilt, and sacral tilt are inconsistently described in the literature. This study aimed to investigate the impact of medium-height heeled footwear on the static posture parameters of homogeneous young adult standing women. Heel geometry, data acquisition process, as well as data analysis and parameter extraction stage, were controlled. Seventy-six healthy young adult women with experience in wearing high-heeled shoes were enrolled. Data of fifty-three subjects were used for analysis due to exclusion criteria (scoliotic posture or missing measurement data). A custom structured light surface topography measurement system was used for posture parameters assessment. Three barefoot measurements were taken as a reference and tested for the reliability of the posture parameters. Two 30-degree wedges were used to imitate high-heel shoes to achieve a repeatable foot position. Our study confirmed the significant (p < 0.001) reduced vertical balance angle and pelvis inclination angle with large and medium-to-large effects, respectively, due to high-heel shoes. No significant differences were found in the kyphosis or lordosis angles. High-heeled shoes of medium height in young asymptomatic women can lead to a straightening effect associated with a reduced vertical balance angle and decreased pelvic inclination.