Influence of investigator experience on reliability of adult acquired flatfoot deformity measurements using weightbearing computed tomography

BackgroundOur purpose was to assess the reliability of measurements of adult-acquired flatfoot deformity (AAFD) taken by investigators of different levels of clinical experience using weightbearing computed tomography (WBCT).MethodsNineteen AAFD patients underwent WBCT. Three investigators with different levels of clinical experience made AAFD measurements in axial, coronal, and sagittal planes. Intra- and interobserver reliability were assessed. Mean values for each measurement were compared between investigators.ResultsAfter a training protocol, substantial to perfect intra- and interobserver reliability was observed for most measures, regardless of the investigator’s experience level. Significant differences between investigators were observed in 2 of 21 measured parameters: medial cuneiform–first metatarsal angle (P = 0.003) and navicular–medial cuneiform angle (P = 0.001).ConclusionsAAFD radiographic measurements can be performed reliably by investigators with different levels of clinical experience using WBCT.Level of evidenceLevel II, prospective comparative study.     

Hindfoot alignment of adult acquired flatfoot deformity: A comparison of clinical assessment and weightbearing cone beam CT examinations

BackgroundClinical assessment of hindfoot alignment (HA) in adult acquired flatfoot deformity (AAFD) can be challenging and weightbearing (WB) cone beam CT (CBCT) may potentially better demonstrate this three-dimensional (3D) deformity. Therefore, we compared clinical and WB CBCT assessment of HA in patients with AAFD.MethodsIn this prospective study, we included 12 men and 8 women (mean age: 52.2, range: 20–88) with flexible AAFD. All subjects also underwent WB CBCT and clinical assessment of hindfoot alignment. Three fellowship-trained foot and ankle surgeons performed six hindfoot alignment measurements on the CT images. Intra- and Inter-observer reliabilities were calculated using intra-class correlation (ICC). Measurements were compared by paired T-tests, and p-values of less than 0.05 were considered significant.ResultsThe mean of clinically measured hindfoot valgus was 15.2 (95% confidence interval [CI]: 11.5–18.8) degrees. It was significantly different from the mean values of all WB CBCT measurements: Clinical Hindfoot Alignment Angle, 9.9 (CI: 8.9–11.1) degrees; Achilles tendon/Calcaneal Tuberosity Angle, 3.2 (CI: 1.3–5.0) degrees; Tibial axis/Calcaneal Tuberosity Angle, 6.1 (CI: 4.3–7.8) degrees; Tibial axis/Subtalar Joint Angle 7.0 (CI: 5.3–8.8) degrees, and Hindfoot Alignment Angle 22.8 (CI: 20.4–25.3) degrees. We found overall substantial to almost perfect intra- (ICC range: 0.87–0.97) and inter-observer agreements (ICC range: 0.51–0.88) for all WB CBCT measurements.ConclusionsUsing 3D WB CBCT can help characterize the valgus hindfoot alignment in patients with AAFD. We found the different CT measurements to be reliable and repeatable, and to significantly differ from the clinical evaluation of hindfoot valgus alignment.Level of evidence: Level II—prospective comparative study.     

Evaluation of peritalar subluxation in adult acquired flatfoot deformity using computed tomography and weightbearing multiplanar imaging

Background

The aim of this study was to assess the inferior talus-superior talus (inf-tal-sup-tal) angle (previously proven reliable in multiplanar-weight bearing imaging (MP-WB)) on both computed tomography (CT) and MP-WB scans. We sought to compare the angle between the two modalities in both AAFD and control groups, as well as to compare the groups to each other.

Accuracy of cone-beam computed tomography for syndesmosis injury diagnosis compared to conventional computed tomography

BackgroundSyndesmosis injury can lead to ankle mortise instability and early osteoarthritis. Several multiple detector computed tomography (MDCT) methods for measurement have been developed. Weight-bearing cone beam CT (WB CBCT) is an emerging technique that offers the possibility of upright-position scanning and lower doses. This study sought to assess the diagnostic accuracy of WB CBCT in syndesmose injury compared to MDCT, with instability confirmed via manual testing upon arthroscopic examination.MethodsThree musculoskeletal radiologists with different levels of expertise prospectively analyzed 11 MDCT and eight WB CBCT scans of the same trauma-afflicted ankles with clinical suspicion of syndesmosis lesion over a period of 5 months. They evaluated 10 methods of measurement in both sides. Syndesmosis was considered pathological on arthroscopic examination in four patients. Correlation between readers was evaluated with intra-class correlation testing (p < 0.05 was considered significant). Capacity of discrimination was assessed by area under the curve (AUC) for all methods.ResultsInter-observer agreement was near excellent for both WB CBCT and MDCT for the anterior tibio-fibular (TF) distance (ICC = 0.781 and 0.831, respectively), posterior TF distance (ICC = 0.841 and 0.826), minimal TF distance (ICC = 0.899 and 0.875), and TF surface (ICC = 0.93 and 0.84). AUC were better for MDCT than WB CBCT in assessing syndesmosis instability for: anterior TF distance (ROC = 0.869 vs. 0.555, p = 0.01), minimal TF distance (ROC = 0.883 vs. 0.608, p = 0.02) and antero-posterior fibular translation (ROC = 0.894 vs. 0.467, p = 0.006).ConclusionsMDCT demonstrated better ability to distinguish pathological syndesmosis than WB CBCT, with the antero-posterior fibular translation the best discriminating measurement. The physiological widening of the contralateral syndesmosis occurring with the WB CBCT upright position may explain these results.     

Analysis of biomechanical stresses caused by hindfoot joint arthrodesis in the treatment of adult acquired flatfoot deformity: A finite element study

BackgroundTreatments of adult acquired flatfoot deformity in early stages (I–IIa–IIb) are focused on strengthening tendons, in isolation or combined with osteotomies, but in stage III, rigidity of foot deformity requires more restrictive procedures such as hindfoot joint arthrodesis. Few experimental studies have assessed the biomechanical effects of these treatments, because of the difficulty of measuring these parameters in cadavers. Our objective was to quantify the biomechanical stress caused by both isolated hindfoot arthrodesis and triple arthrodesis on the main tissues that support the plantar arch.MethodsAn innovative finite element model was used to evaluate some flatfoot scenarios treated with isolated hindfoot arthrodesis and triple arthrodesis.Results and conclusionsWhen arthrodeses are done in situ, talonavicular seems a good option, possible superior to subtalar and at least equivalent to triple. Calcaneocuboid arthrodesis reduces significantly both fascia plantar and spring ligament stresses but concentrates higher stresses around the fused joint.     

CT血管造影技术在枕颈手术中的应用

目的 评价在枕颈手术中应用术前CT血管造影(CTA)技术的价值.方法 16例枕颈疾病患者在术前进行CTA检查.完成3D重建后,评价椎动脉寰枢段走行、分支.测定寰椎椎动脉沟距中线距离、侧块中点距中线距离、枢椎峡部宽度等指标.根据影像学研究进行后路枕颈固定2例,后路寰枢固定10例,经口1例,经口 枕颈固定2例,单纯减压手术1例.结果 影像学研究发现椎动脉不对称3例,异常分支2例, 直接入颅1例, 肿瘤侵犯1例.16例手术均未出现医源性椎动脉及脊髓损伤.结论 在枕颈部畸形及肿瘤患者存在很高的椎动脉异常发生率,CTA是进行枕颈部手术前一项很有价值的检查,降低了损伤椎动脉的发生率.     

锥形束CT与根尖片对牙根纵裂诊断的对比研究

目的:比较锥形束CT(CBCT)和X线根尖片在牙根纵裂诊断中的准确度,探讨CBCT对牙根纵裂诊断的价值。方法:选取临床检查中疑似牙根纵裂患牙50例,分别进行X线根尖片、CBCT检查诊断和外科手术诊断;对X线根尖片和CBCT对牙根纵裂的诊断结果进行统计分析。结果:CBCT诊断牙根纵裂的敏感度(83.33%)高于X线根尖片诊断牙根纵裂的敏感度为(47.61%),P<0.05。结论:CBCT比X线根尖片能更准确诊断牙根纵裂,有助于牙根纵裂诊断。     

Prospective nonrandomized study to evaluate cone beam computed tomography for technical assessment of standard and complex endovascular aortic repair

ObjectiveThe objective of this study was to analyze the utility of cone beam computed tomography (CBCT) for technical assessment of standard and complex endovascular aneurysm repair (EVAR).MethodsData of consecutive patients who underwent standard or complex EVAR in 2016 and 2017 at our institution were entered into a prospective database and analyzed retrospectively. There were 154 patients (126 male; mean age, 74 ± 8 years) enrolled in a prospective study between 2016 and 2017. A total of 170 aortic procedures were investigated, including 85 fenestrated-branched EVARs (F-BEVARs), 42 abdominal and thoracic EVARs, 32 EVARs with iliac branch devices, and 11 aorta-related interventions. Technical assessment was done using CBCT with and without contrast enhancement, digital subtraction angiography (DSA), and computed tomography angiography (CTA). Patients with stage 3B or stage 4 chronic kidney disease had CBCT without contrast enhancement. Radiation exposure (mean dose-area product), effective dose (ED), and amount of iodine contrast agent were analyzed. End points were presence of any endoleak, positive findings warranting possible intervention (stent kink or compression, type I or type III endoleak, dissection, thrombus), and need for secondary intervention.ResultsRadiation exposure and amount of iodine contrast agent were significantly higher (P < .05) for F-BEVAR compared with other aortic procedures (174±101 Gy∙cm² vs 1135±113 Gy∙cm² and 144±60 mL vs 122±49 mL). ED averaged 74±36 mSv for the aortic procedure, 18 ± 18 mSv for fluoroscopy, 7 ± 7 mSv for DSA acquisition, 15±7 mSv for CBCT, and 34±17 mSv for CTA imaging (P < .001). Endoleak detection was significantly higher (P < .001) with CBCT (53%) compared with DSA (14%) and CTA (46%). CBCT identified 52 positive findings in 43 patients (28%), higher for F-BEVAR compared with other aortic procedures (35% vs 16%; P = .01). Positive findings included stent compression or kink in 29 patients (17%), type I or type III endoleak in 16 patients (10%), and arterial dissection or thrombus in 7 patients (5%). Of these, 28 patients (18%) had positive findings that prompted an intraoperative (17%) or delayed intervention (1%). Another 15 patients (10%) with minor positive findings were observed with no clinical consequence. DSA alone would not have detected positive findings in 34 of 43 patients (79%), including 21 patients (49%) who needed secondary interventions. CTA diagnosed two (1%) additional endoleaks requiring intervention (one type IC, one type IIIC) that were not diagnosed by CBCT. Replacing DSA and CTA by CBCT would have resulted in 53% ± 13% reduction in amount of iodine contrast agent and 55% ± 12% reduction in ED (P < .05).ConclusionsCBCT reliably detected positive findings prompting immediate revisions in nearly one of five patients, with the highest rates among F-BEVAR patients. Detection of any endoleak was higher with CBCT compared with DSA or CTA, but most endoleaks were observed. DSA alone failed to detect positive findings warranting revisions.     

Prostatic artery embolization using three-dimensional cone-beam computed tomography

PurposeThe purpose of this study was to report the use of three-dimensional (3D) cone-beam computed tomography (CBCT) for prostatic artery embolization (PAE) in patients with benign prostatic hypertrophy (BPH).Materials and methodsTwenty-three consecutive men who underwent PAE using 3D CBCT from June 2016 to September 2018, were retrospectively included in this observational single-center study. There were 23 men with a mean age of 73 ± 12 (SD) years (range: 52–94 years) with moderate to severe lower urinary tract symptoms (mean international prostate symptom score, 21 ± 5.7 [SD]; range: 9–30) due to BPH (mean prostate weight, 100 g ± 63 [SD]; range: 30–250 g). PAEs were analyzed with respect to procedure time, fluoroscopy time, technical success, complications and dosimetric indices.ResultsThe mean catheterization time of the prostatic artery from the internal iliac artery was 17.3 ± 12.5 (SD) min (range: 8–57 min) on the right side and 23.6 ± 14.9 (SD) min (range: 6–54 min) on the left side. A technical success was achieved in 21 patients (21/23; 91%). PAE was bilateral in 14 patients (14/21; 66%) and unilateral in 7 patients (7/21; 33%). No occurrence of non-target embolization was reported. The mean dose area product was 146.7 ± 47.9 (SD) Gy.cm² (range: 54–254 Gy.cm²) and mean cumulative air kerma was 771.4 ± 333.3 (SD) mGy; range: 280–1560 mGy. The mean fluoroscopy time was 42.3 ± 23.1 (SD) min (range: 19.4–118.2 min).Conclusion3D CBCT is a useful tool to identify the prostatic arteries and facilitates catheterization of prostatic arteries with an acceptable level of radiation exposure.     

Optimal acquisition time to discriminate between breast cancer subtypes with contrast-enhanced cone-beam CT

PurposeTo identify the optimal acquisition time to best discriminate between benign and malignant breast lesions on contrast-enhanced cone beam CT (CE-CBCT) and evaluate the potential of CE-CBCT to differentiate between breast cancer subtypes.Material and methodA total of 98 women with a mean age of 49 ± 10 (SD) years (range: 29–77 years) with 100 BI-RADS 4 or 5 breast lesions were prospectively included. CE-CBCT images were obtained at 1- and 2-min after intravenous administration of iodinated contrast material. Contrast enhancement of breast lesions on CE-CBCT were evaluated and compared between different subtypes. Cut-off values for best discriminating between benign and malignant breast lesions with CE-CBCT were obtained from receiver operating characteristic curves.ResultsMalignant breast lesions showed greater enhancement than benign ones at 1-min (67.28 ± 39.79 [SD] HU vs. 42.27 ± 40.31 [SD] HU, respectively; P = 0.007) and 2-min (70.93 ± 38.05 [SD] HU vs. 48.94 ± 41.83 [SD] HU, respectively; P = 0.016) after intravenous administration of contrast material. At 1-min after intravenous administration of contrast material, an optimal cut-off value of 54.43 HU was found to best discriminate between malignant and benign breast lesions (AUC = 0.681; 95%CI: 0.558–0.805; P = 0.006) yielding 69.0% sensitivity (95%CI: 56.9–79.5%) and 69.2% specificity (95% CI: 48.2–85.7%). At 2-min, an optimal cut-off value of 72.65 HU was found to best discriminate between malignant and benign breast lesions (AUC = 0.654; 95%CI: 0.535–0.774; P = 0.020) yielding 50.7% sensitivity (95%CI: 38.6–62.8%) and 80.8% specificity (95%CI: 60.6–93.4%). CE-CBCT helped differentiate between immunohistochemical subtypes of breast lesions with lowest enhancement for triple negative lesions. No differences in enhancement were found among histopathological subtypes lesions at 1-min (P = 0.478) and 2-min (P = 0.625).ConclusionCE-CBCT helps discriminate between malignant and benign breast lesions, with best capabilities obtained at 1-min after intravenous administration of contrast material. For malignant lesions, quantitative analysis of enhancement on CE-CBCT helps differentiate between immunohistochemical subtypes.     

锥形束CT在上颌埋伏中切牙正畸治疗中的应用

目的:评价锥形束CT(CBCT)在上颌埋伏中切牙正畸治疗中的应用价值。方法:选择在我院就诊的上颌埋伏中切牙患者54例(男32例,女22例),应用CBCT进行扫描和图像三维重建,显示埋伏中切牙的形态、位置、牙根弯曲情况以及与邻牙的关系。结果:经CBCT三维重建后,54例病例均清晰的显示了埋伏中切牙的牙体形态、唇腭向位置、萌出方向、牙根弯曲情况以及与邻牙的关系。结论:CBCT检查能提供准确,直观的信息,对上颌埋伏阻生的诊断,治疗设计具有更好的指导意义。     

Biotenodesis screw for fixation of FDL transfer in the treatment of adult acquired flatfoot deformity

BACKGROUND: In stage II PTTD, flexor digitorum longus (FDL) tendon transfer with an adjunctive bony procedure is the most common method of surgical correction. This paper presents an alternative method of fixation with a biotenodesis interference screw (Arthrex Biotenodesis Screw System) that allows proper tensioning of the FDL tendon transfer. MATERIALS AND METHODS: We retrospectively reviewed 25 consecutive patients who underwent FDL tendon transfer utilizing a biotenodesis interference screw. Intraoperative stability was noted and any loss of correction was assessed postoperatively. RESULTS: Stable fixation was achieved in 24 of the 25 patients who underwent FDL tendon transfer for PTTD. We were not able to achieve stable fixation in one patient due to improper placement of the bone tunnel. This was recognized intraoperatively and did not affect the final outcome. CONCLUSION: This method is technically easier to perform than the recommended technique by the manufacturer. It can be performed through a slightly smaller incision without disrupting the normal interconnections between flexor hallucis long (FHL) and FDL tendon at the Knot of Henry.     

C臂锥形束CT的基本理论及其在介入放射学中的应用

C臂锥形束CT以C臂旋转运动、平板探测器采集和计算机重建技术进行血管造影和软组织成像,实现了二维摄影、透视与三维CT影像的有效结合,在头颈部、腹部血管及肿瘤介入治疗和非血管介入治疗领域具有独特优势。本文对C臂锥形柬CT的基本理论及在介入放射学中的应用进行综述。     

Impact of onlay fusion and cone beam computed tomography on radiation exposure and technical assessment of fenestrated-branched endovascular aortic repair

Objective

The objective of this study was to analyze the impact of advanced imaging applications and cone beam computed tomography (CBCT) on radiation exposure of the patient and operator and detection of technical problems during fenestrated-branched endovascular aortic repair (F-BEVAR) for treatment of pararenal aneurysms and thoracoabdominal aortic aneurysms (TAAAs).

Quantitative computed tomography for measuring bone mineral density in athletes

We studied the effect of different training patterns on vertebral trabecular and cortical bone mineral density (BMD) in male athletes using quantitative computed tomography. Vertebral trabecular (t) and cortical (c) BMDs of the first three lumbar vertebrae were measured using single energy quantitative computed tomography in 51 athletes including 10 weight lifters (mean age 20 years), 13 soccer players (mean age 27 years), 28 wrestlers (mean age 17 years), and 45 age-matched volunteers (mean age 21 years). Measured BMDs were correlated with age, body height and weight, training hours per week, sports years, and type of physical activity. Vertebral tBMDs were found to be 44%, 23%, and 24% higher in the weight lifters, soccer players, and wrestlers, respectively, compared with the volunteers. The corresponding cBMDs were 18%, 6%, and 11% higher than that of volunteers. There was significant correlation between the trabecular and cBMD, and height of the athletes, sports years, training hours per week, and physical activity. The most significant correlation with BMD was the type of physical activity. Both the height of the subjects and physical activity variables showed variations of 47% and 32% in trabecular and cBMD, respectively. According to the multiple analysis of variance (MANOVA) only the physical activity factor was effective, with a significance level ofP<0.01; the other factors and interactions were not effective (P>0.05) on trabecular and cBMD. Different training patterns have a different anabolic effect on both trabecular and cBMDs of the vertebrae, and this effect is more pronounced on the trabecular compartment. Weight lifting showed the highest anabolic effect on both trabecular and cBMDs compared with soccer playing and wrestling. Of the independent variables, physical activity showed the highest anabolic effect on the vertebrae. These results may have implications for devising exercise strategies to reduce the possibility of fracture in old age.