Monitoring of Curve Progression in Patients with Adolescent Idiopathic Scoliosis Using 3-D Ultrasound.

OBJECTIVE: The aim of the work described here was to determine whether 3-D ultrasound can provide results comparable to those of conventional X-ray examination in assessing curve progression in patients with adolescent idiopathic scoliosis (AIS). METHODS: One hundred thirty-six participants with AIS (42 males and 94 females; age range: 10-18 y, mean age: 14.1 ± 1.9 y) with scoliosis of different severity (Cobb angle range: 10º- 85º, mean: of 24.3 ± 14.4º) were included. Each participant underwent biplanar low-dose X-ray EOS and 3-D ultrasound system scanning with the same posture on the same date. Participants underwent the second assessment at routine clinical follow-up. Manual measurements of scoliotic curvature on ultrasound coronal projection images and posterior-anterior radiographs were expressed as the ultrasound curve angle (UCA) and radiographic Cobb angle (RCA), respectively. RCA and UCA increments ≥5º represented a scoliosis progression detected by X-ray assessment and 3-D ultrasound assessment, respectively. RESULTS: The sensitivity and specificity of UCA measurement in detecting scoliosis progression were 0.93 and 0.90, respectively. The negative likelihood ratio of the diagnostic test for scoliosis progression by the 3-D ultrasound imaging system was 0.08. CONCLUSION: The 3-D ultrasound imaging method is a valid technique for detecting coronal curve progression as compared with conventional radiography in follow-up of AIS. Substituting conventional radiography with 3-D ultrasound is effective in reducing the radiation dose to which AIS patients are exposed during their follow-up examinations.

Semi-automatic ultrasound curve angle measurement for adolescent idiopathic scoliosis.

PURPOSE: Using X-ray to evaluate adolescent idiopathic scoliosis (AIS) conditions is the clinical gold standard, with potential radiation hazards. 3D ultrasound has demonstrated its validity and reliability of estimating X-ray Cobb angle (XCA) using spinous process angle (SPA), which can be automatically measured. While angle measurement with ultrasound using spine transverse process-related landmarks (UCA) shows better agreed with XCA, its automatic measurement is challenging and not available yet. This research aimed to analyze and measure scoliotic angles through a novel semi-automatic UCA method. METHODS: 100 AIS subjects (age: 15.0 ± 1.9 years, gender: 19 M and 81 F, Cobb: 25.5 ± 9.6°) underwent both 3D ultrasound and X-ray scanning on the same day. Scoliotic angles with XCA and UCA methods were measured manually; and transverse process-related features were identified/drawn for the semi-automatic UCA method. The semi-automatic method measured the spinal curvature with pairs of thoracic transverse processes and lumbar lumps in respective regions. RESULTS: The new semi-automatic UCA method showed excellent correlations with manual XCA (R2 = 0.815: thoracic angles R2 = 0.857, lumbar angles R2 = 0.787); and excellent correlations with manual UCA (R2 = 0.866: thoracic angles R2 = 0.921, lumbar angles R2 = 0.780). The Bland-Altman plot also showed a good agreement against manual UCA/XCA. The MADs of semi-automatic UCA against XCA were less than 5°, which is clinically insignificant. CONCLUSION: The semi-automatic UCA method had demonstrated the possibilities of estimating manual XCA and UCA. Further advancement in image processing to detect the vertebral landmarks in ultrasound images could help building a fully automated measurement method. LEVEL OF EVIDENCE: Level III.

3D ultrasound imaging provides reliable angle measurement with validity comparable to X-ray in patients with adolescent idiopathic scoliosis.

BACKGROUND & OBJECTIVE: The application of ultrasound imaging for spine evaluation could minimize radiation exposure for patients with adolescence idiopathic scoliosis (AIS). A customized three-dimensional (3D) ultrasound imaging system has been demonstrated to provide reliable and valid coronal curvature measurements. However, these measurements were using the spinous processes as anatomical reference, leading to a predictable underestimation of the traditionally used Cobb angles. An alternative 3D ultrasound image reconstruction method was applied to create coronal images with more lateral features for angle measurement. The objective of this study was to test the reliability and the validity of this angle, the ultrasound curve angle (UCA), and compare the UCA with the Cobb angles on X-ray images of patients with AIS. MATERIALS AND METHODS: This study was divided into: 1) Investigation of intra- and inter-reliability between two raters for measuring the UCA and two operators for acquiring ultrasound images; 2) Investigation of the validity between the radiographic Cobb angle and the UCA. Fifty patients and 164 patients with AIS, were included in the two stages, respectively. Patients underwent bi-planar X-ray and 3D ultrasound scanning on the same day. The proposed UCA was used to measure the coronal curvature from the ultrasound coronal images, which were formed using a newly customized volume projection imaging (VPI) method. The intra-rater/operator and inter-rater and operator reliability of the UCA were tested by intra-class correlation coefficient (ICC) (3,1) and (2,1), respectively. The validity of UCA measurements as compared to radiographic Cobb angles was tested by inter-method ICC (2,1), mean absolute difference (MAD), standard error of measurement (SEM), Pearson correlation coefficient and Bland-Altman statistics. The level of significance was set as 0.05. RESULTS: Excellent intra-rater and intra-operator (ICC (3,1)≥0.973) and excellent inter-rater and inter-operator reliability (ICC (2,1)≥0.925) for UCA measurement, with overall MAD and SEM no more than 3.5° and 1.7° were demonstrated for both main thoracic and (thoraco)lumbar curvatures. Very good correlations were observed between UCA and Cobb angle for main thoracic ( R 2 =0.893) and (thoraco)lumbar ( R 2 =0.884) curves. The mean (SD) measurements in terms of radiographic Cobb and UCA were 27.2 â€‹± â€‹11.6° and 26.3 â€‹± â€‹11.4° for main thoracic curves; and 26.2 â€‹± â€‹11.4° and 24.8 â€‹± â€‹9.7° for (thoraco)lumbar curve respectively. One hundred sixty-four subjects (33 male and 131 female subjects; 11-18 years of age, mean of 15.1 â€‹± â€‹1.9 years) were included for the validity session. Excellent inter-method variations (ICC (2,K) ≥0.933) with overall MAD and SEM no more than 3.0° and 1.5° were demonstrated for both main thoracic and (thoraco)lumbar curvatures. In addition, Bland-Altman plots demonstrated an acceptable agreement between ultrasound and radiographic Cobb measurements. CONCLUSION: In this study, very good correlations and agreement were demonstrated between the ultrasound and X-ray measurements of the scoliotic curvature. Judging from the promising results of this study, patients with AIS with different severity of curves can be evaluated and monitored by ultrasound imaging, reducing the usage of radiation during follow-ups. This method could also be used for scoliosis screening.The Translational potential of this article: Ultrasound curve angle (UCA) obtained from 3D ultrasound imaging system can provide reliable and valid evaluation on coronal curvature for patients with AIS, without the need of radiation.

Investigation of the Phenomenon of Coronal-Sagittal Curvature Coupling on Curve Progression: An Exploratory Study using 3-D Ultrasound.

A 3-D ultrasound system was determined to provide reliable and valid results for scoliosis assessment in the coronal and sagittal planes. The objective of this study was to investigate whether 3-D ultrasound can detect coronal-sagittal coupling and to study its potential effect on curve progression in patients with adolescence idiopathic scoliosis (AIS) as per the traditional Cobb angle classification. Radiographic and ultrasonic coronal and sagittal curvatures of 126 patients with AIS were evaluated. Thoracic kyphosis (TK) and lumbar lordosis (LL) with different coronal deformity were compared correspondingly based on either main thoracic or (thoraco)lumbar curve groups. The TK and LL of patients with single curves were also compared with study the curve effect on sagittal curvatures. A prospective cohort of 51 patients were followed for an average of 23 months for preliminary progression investigation. TKs in patients with larger main thoracic Cobb angles was significantly smaller than those with smaller main thoracic Cobb angles, judging by the results obtained from ultrasound and X-ray. The TKs of patients with only single right main thoracic curves were significantly smaller than those of patients with only single left (thoraco)lumbar curves. In addition, patients with progressive curves were observed to be relative hypokyphotic during early visits.

Patients With Idiopathic Scoliosis Run an Increased Risk of Schizophrenia.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: To investigate a possible linkage between idiopathic scoliosis (IS) and schizophrenia in an adolescent population. SUMMARY OF BACKGROUND DATA: There is an interesting link between schizophrenia and idiopathic scoliosis: schizophrenia is a disturbance of mental equilibrium, and scoliosis of physical equilibrium, both are multifactorial, genetically determined, start at a young age, and brain development is thought to play a role. Furthermore, both may be presenting symptoms of the genetic disorder 22q11 deletion syndrome. This study poses the question whether these two poorly understood disorders are related. METHODS: A retrospective cohort study was conducted and consisted of 3,702 Swedish adolescents, collected from the National Patient Register, that underwent inpatient care for IS during 1997-2015. These were matched by age, sex, and date of diagnosis to 370,200 controls, collected from Swedish population data, and then followed up in the National Patient Register to identify in- and outpatient care for schizophrenia diagnosis. Follow-up time was calculated from first IS diagnosis date until date of schizophrenia diagnosis or end of follow-up. Cox proportional regression analysis was performed to estimate hazard ratios (HRs) with 95% confidence intervals (CIs) for being diagnosed with schizophrenia. RESULTS: Over a median follow-up time of 9.5 years, 0.7% of patients with IS developed schizophrenia versus 0.5% of controls (p = .04). The risk of schizophrenia was significantly higher in patients with IS (HR, 1.52; 95% CI, 1.03-2.23). Using only hospitalized schizophrenia as event, the prevalence for schizophrenia was 0.5% versus 0.3% (p ≤.01; HR, 1.83; 95% CI, 1.17-2.84). CONCLUSION: This study suggests that patients with IS have increased risk of schizophrenia. Dissatisfaction with one's physical appearance might lead to psychological distress and provoke mental illness in predisposed persons. Alternatively, these two disorders may share a common genetic background. LEVEL OF EVIDENCE: Level 2B.