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1.
Artículo en Inglés | MEDLINE | ID: mdl-39299643

RESUMEN

BACKGROUND: Plasma is a collection of active particles generated by dissociating molecules and ionizing atoms through applying high energy to a gas, such as high-sound heating or electrical shock. Recently, many reports have been published on the effectiveness of non-thermal atmospheric pressure gas discharge plasma (NTAPP) on living organisms. Furthermore, we have reported on the promotion of bone and tendon repair by NTAPP irradiation. We hypothesized that irradiation of NTAPP would promote the repair of the tendon-bone junction in a rotator cuff repair. This study investigated the effect of NTAPP irradiation on the healing process of the tendon-bone junction. METHODS: Among 36 Japanese white rabbits, the infraspinatus tendon was detached from the humeral insertion site. A 3.2 mm bone tunnel was then created at the original insertion site of the infraspinatus muscle. The left shoulder was irradiated with NTAPP at a distance of 1 cm from the bone tunnel for 5 minutes (plasma-treated group), while the right shoulder was not irradiated (control group). The rabbits were sacrificed at 2, 4, and 8 weeks postoperatively, and six of each were used for histological evaluation. Mechanical tests were also performed on six specimens each at 4 and 8 weeks. RESULTS: Histological evaluation showed that at 4 weeks, the histological tendon to bone maturing score was 6.8±1.3 in the plasma-treated group and 4.8±1.6 in the control group (p<0.01); at 8 weeks it was 9.0±1.0 in the plasma-treated group and 5.2±1.1 in the control group (p<0.01). Fibrocartilage formation and new bone formation were observed at both 4 and 8 weeks. In the mechanical test, the plasma-treated group had 75.0 ± 18.9 N in ultimate load to failure at 8 weeks. In the control group, it was 51.1±7.9 N. (p=0.04) CONCLUSION: The repair of the rotator cuff at the tendon-bone junction was significantly improved at 4 and 8 weeks by irradiation with NTAPP.

2.
Biochem Biophys Res Commun ; 736: 150512, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39142235

RESUMEN

Combustible cigarette and heated tobacco products (HTPs), the two most frequently used tobacco products, negatively affect bone healing. However, whether smoking cessation following fracture benefits bone healing is unclear. Therefore, this study investigated the effect of smoking cessation immediately after surgery on reduced fracture healing induced by smoking. Smoking combustible cigarettes and heated tobacco products generates cigarette smoking extracts (CSE) (extracts from combustible cigarettes [cCSE] and from HTPs [hCSE], respectively). In vivo, CSEs were injected intraperitoneally into rat models for 3 weeks before femoral midshaft osteotomy and fixation. The rats were then divided into CSE continuation and cessation groups postoperatively. Micro-computed tomography (µCT) and biomechanical analyses were performed 6 weeks postoperatively to assess bone union at the fracture site. In vivo study showed µCT assessment also revealed significantly higher cortical bone mineral density (p = 0.013) and content (p = 0.013), and a higher bone union score (p = 0.046) at the fracture site in the cCSE cessation group than in the cCSE continuation group. Biomechanical assessment revealed that elasticity at the fracture site was significantly higher in the cCSE cessation group than in the cCSE continuation group (p = 0.041). These findings provide that smoking cessation, particularly of combustible cigarette, immediately after a fracture accelerates bone fracture healing and increases mechanical strength at the fracture site.

3.
Spine J ; 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39147142

RESUMEN

BACKGROUND CONTEXT: Orthotic treatment is a common option for the conservative treatment of osteoporotic vertebral fractures (OVF). However, there is insufficient evidence of its clinical benefit. PURPOSE: To investigate the effectiveness of orthotic treatment for OVF. STUDY DESIGN/SETTING: Retrospective cohort study with data from two prospective studies. PATIENT SAMPLE: This study included 160 patients with fresh OVF enrolled in 2012 and 2020 prospective cohort studies. OUTCOME MEASURES: The visual analog scale (VAS) score for low back pain was used for clinical outcomes, and radiographic parameters included the percent height of the vertebra and angular change of the vertebral body. Moreover, the occurrence of secondary vertebral fractures was followed-up over time. METHODS: The patients were divided into brace and no-brace groups and were matched according to propensity score for age, sex, anterior percent height at the initial examination, and presence of old OVFs. Hazard ratio for the cumulative incidence of secondary vertebral fractures with and without bracing were calculated and analyzed using the generalized Wilcoxon test. In addition, the brace group was divided into soft and rigid brace groups and compared with the no-brace group. RESULTS: Each group had 61 cases after propensity score matching. There were no significant differences in the VAS improvement for low back pain and the change in percent height of the anterior and posterior walls from initial examination to 6 months after injury (p=.87, p=.39 and p=.14, respectively, mixed-effect models). Meanwhile, the mean angular change of fractured vertebrae was 4.3° / 3.2° initially and 1.2° / 2.5° at 6 months (the brace group / no-brace group, respectively; p=.007, mixed-effect models). A significant difference was also observed between the rigid brace group and the no-brace group (p=.008, mixed effect models). The incidence of secondary vertebral fractures was 1.6% / 11.4% at 1 month, indicating a significant difference (the brace group / no-brace group, respectively; p = .028). The hazard ratio for the cumulative incidence of secondary fractures due to orthotic treatment was 0.47 (95% confidence interval 0.20-1.09, p=.054). CONCLUSIONS: Although orthotic treatment for fresh OVF did not relieve pain, it might contribute to the stabilization of the fractured vertebra, especially using a rigid brace. Moreover, it might influence a reduction of the imminent vertebral fracture risk immediately after the onset of OVF. CLASSIFICATIONS: Clinical study.

4.
Heliyon ; 10(4): e26277, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38390153

RESUMEN

When athletes in ball game sports start sprinting in the forward direction from a parallel stance, they commonly use the forward- and false-step techniques. Previous studies focusing on the performance of short-distance sprints starting in the forward direction have demonstrated that the false-step technique is superior to the forward-step technique. Although athletes start sprinting in various directions based on relevant visual cues, such as movements of the ball or the opponent players, the effectiveness of each technique for starting a sprint in the other direction is still unclear. This study aims to clarify the effectiveness of each technique in improving the performance of the short-distance sprint starting in the lateral direction. In this study, 20 athletes started 5-m sprints in the right direction from the parallel stance using either of these two techniques. Kinematic and kinetic analyses were performed from movement initiation to the flight phase after the second step in the sprinting direction. The average and terminal sprint velocities throughout this range were larger in the forward-step technique (p = 0.039 and 0.003), indicating its superiority in traveling and accelerating performance. The change of sprint velocity in the initial phase until the contact of the first step in the sprinting direction was smaller in the false-step technique (p < 0.001), although this phase included "false step." These results indicate that the forward-step technique is superior in sprints starting in the lateral direction, and the advantage results from greater acceleration in the initial phase immediately after movement initiation. These findings imply the sprint-directional dependence of the relative superiority of these techniques, providing an impetus for athletes and coaches to consider and establish the effective training and coaching methods of short-distance sprints.

5.
Spine (Phila Pa 1976) ; 49(6): 378-384, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38126538

RESUMEN

STUDY DESIGN: Multicenter, prospective cohort study. OBJECTIVE: The current study aimed to identify the incidence of residual paresthesias after surgery for degenerative cervical myelopathy (DCM), and to demonstrate the impact of these symptoms on clinical outcomes and patient satisfaction. SUMMARY OF BACKGROUND DATA: Surgery for DCM aims to improve and/or prevent further deterioration of physical function and quality-of-life (QOL) in the setting of DCM. However, patients are often not satisfied with their treatment for myelopathy when they have severe residual paresthesias, even when physical function and QOL are improved after surgery. MATERIALS AND METHODS: The authors included 187 patients who underwent laminoplasty for DCM. All patients were divided into two groups based on their visual analog scale score for paresthesia of the upper extremities at one year postoperatively (>40 vs. ≤40 mm). Preoperative factors, changes in clinical scores and radiographic factors, and satisfaction scales at one year postoperatively were compared between groups. The authors used mixed-effect linear and logistic regression modeling to adjust for confounders. RESULTS: Overall, 86 of 187 patients had severe residual paresthesia at one year postoperatively. Preoperative patient-oriented pain scale scores were significantly associated with postoperative residual paresthesia ( P =0.032). A mixed-effect model demonstrated that patients with severe postoperative residual paresthesia showed significantly smaller improvements in QOL ( P =0.046) and myelopathy ( P =0.037) than patients with no/mild residual paresthesia. Logistic regression analysis identified that residual paresthesia was significantly associated with lower treatment satisfaction, independent of improvements in myelopathy and QOL (adjusted odds ratio: 2.5, P =0.010). CONCLUSION: In total, 45% of patients with DCM demonstrated severe residual paresthesia at one year postoperatively. These patients showed significantly worse treatment satisfaction, even after accounting for improvements in myelopathy and QOL. As such, in patients who experience higher preoperative pain, multidisciplinary approaches for residual paresthesia, including medications for neuropathic pain, might lead to greater clinical satisfaction. LEVEL OF EVIDENCE: 3.


Asunto(s)
Parestesia , Enfermedades de la Médula Espinal , Humanos , Parestesia/epidemiología , Parestesia/etiología , Estudios Prospectivos , Calidad de Vida , Incidencia , Resultado del Tratamiento , Vértebras Cervicales/cirugía , Enfermedades de la Médula Espinal/epidemiología , Enfermedades de la Médula Espinal/cirugía , Dolor
6.
Spine (Phila Pa 1976) ; 48(19): 1365-1372, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37389977

RESUMEN

STUDY DESIGN: Prospective cohort study. OBJECTIVE: To identify the effects of multidisciplinary approaches (MAs) to improve social functioning (SF) on 1-year surgical outcomes in patients with cervical myelopathy. SUMMARY OF BACKGROUND DATA: Despite significant improvement in cervical myelopathy, a patient's quality of life (QOL) sometimes does not improve postoperatively. A previous study revealed that SF, rather than myelopathy severity, correlated with QOL improvement after decompression surgery for cervical myelopathy. PATIENTS AND METHODS: This study compared two prospective cohorts in Japan. Patients who underwent cervical laminoplasty for cervical myelopathy from 2018 to 2020 were enrolled in the control cohort. Patients who underwent the same surgery with the same indications between 2020 and 2021 were enrolled in the MA cohort. Patients in the control cohort were treated with a standard care protocol, and those in the MA cohort were treated with a multidisciplinary protocol that focused on SF improvement. The changes in the total Japanese Orthopedic Association (JOA) score and in the domains of the JOA scores (upper limb function, lower limb function, upper limb sensory, and lower limb sensory) from preoperatively to 1 year postoperatively were compared between the control and MA cohorts using a mixed-effect model. RESULTS: The control and MA cohorts comprised 140 and 31 patients, respectively. The improvement in the JOA score was significantly better in the MA cohort than in the control cohort ( P = 0.040). In analyses of each JOA score domain, the improvement of upper limb function was significantly better in the MA cohort than in the control cohort ( P = 0.033). Similarly, the MA cohort demonstrated significantly higher patient-reported outcomes for upper extremity function than the control cohort ( P < 0.001). In addition, the self-care domain of QOL score at 1 year postoperatively was significantly higher in the MA cohort than in the control cohort ( P = 0.047). CONCLUSION: MAs to improve/rebuild a patient's SF were effective in improving cervical myelopathy and the self-care domain of QOL. This study is the first to demonstrate the effectiveness of postoperative MAs in patients with cervical myelopathy. LEVEL OF EVIDENCE: Level 3.


Asunto(s)
Laminoplastia , Enfermedades de la Médula Espinal , Espondilosis , Humanos , Estudios Prospectivos , Calidad de Vida , Vértebras Cervicales/cirugía , Interacción Social , Resultado del Tratamiento , Enfermedades de la Médula Espinal/cirugía , Enfermedades de la Médula Espinal/etiología , Laminoplastia/efectos adversos , Descompresión Quirúrgica , Espondilosis/cirugía
7.
Opt Express ; 31(1): 502-508, 2023 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-36606984

RESUMEN

We quantitatively discussed the effect of core-dependent loss (CDL) on the crosstalk (XT) of multicore fibers (MCFs). In practical ranges of XT and CDL, CDL has no significant effect on power coupling coefficients and XT between cores. Therefore, taking into account the CDL-induced signal attenuation difference among cores is sufficient when considering the signal-to-XT ratio in an MCF with CDL. We also analytically investigated the effect of CDL on XT measurements, and found that the effects of the CDLs induced in an MCF as a measurement target and a measurement setup (including input/output devices) can be canceled in the geometric mean of linear values (or the arithmetic mean of decibel values) of the XT by switching the source core and destination core of the XT.

8.
J Orthop Sci ; 28(4): 895-900, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35718602

RESUMEN

BACKGROUND: Restrictions during the coronavirus disease 2019 (COVID-19) pandemic have decreased physical activity levels, which may result in locomotive syndrome. This study evaluated the change in locomotive syndrome prevalence and associated risk factors among an elderly population before and after a coronavirus outbreak. METHODS: This written self-administered cross-sectional survey was conducted in conjunction with the coronavirus disease vaccination program in Habikino City, Japan. Participants who were aged ≥65 years completed the five-question Geriatric Locomotive Function Scale before and during the pandemic. The diagnosis of locomotive syndrome and its stage was based on the Geriatric Locomotive Function Scale score: stage 1 (2-3 points), 2 (4-5 points), and 3 (≥6 points). Data on lifestyle changes, including regular exercise, during the pandemic were collected. RESULTS: This study included 12,197 participants (36.7% of the city's total elderly residents). The prevalence of locomotive syndrome increased from 41.3% to 47.1% after the outbreak. In total, 765 (6.3% of overall population) and 295 (9.5% of the participants who had stages 1-2 before the pandemic) participants developed locomotive syndrome and stage 3 locomotive syndrome, respectively. The multivariate logistic regression analysis indicated that a decrease in exercise was significantly associated with the onset of locomotive syndrome (all stages) (odds ratio = 2.5, p < 0.001) and locomotive syndrome stage 3 (odds ratio = 2.6, p < 0.001). CONCLUSIONS: Extrapolation of the study's findings to the entire population of Japan suggests that approximately 2 million elderly individuals might develop locomotive syndrome after the coronavirus outbreak. Additionally, 10% of the participants with mild-moderate locomotive syndrome before the pandemic may develop severe locomotive syndrome after the outbreak. The greatest risk factor for new-onset or worsening locomotive syndrome was a decrease in daily exercise. Thus, there is an urgent need for adequate exercise guidelines during the coronavirus pandemic, especially for the elderly population.


Asunto(s)
COVID-19 , Locomoción , Humanos , Anciano , Estudios Transversales , COVID-19/epidemiología , Estilo de Vida , Brotes de Enfermedades , Síndrome , Japón/epidemiología
9.
J Clin Med ; 11(19)2022 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-36233429

RESUMEN

Patient satisfaction is crucial in pay-for-performance initiatives. To achieve further improvement in satisfaction, modifiable factors should be identified according to the surgery type. Using a prospective cohort, we compared the overall treatment satisfaction after microendoscopic lumbar decompression between patients treated postoperatively with a conventional physical therapy (PT) program (control; n = 100) and those treated with a PT program focused on low back pain (LBP) improvement (test; n = 100). Both programs included 40 min outpatient sessions, once per week for 3 months postoperatively. Adequate compliance was achieved in 92 and 84 patients in the control and test cohorts, respectively. There were no significant differences in background factors; however, the patient-reported pain score at 3 months postoperatively was significantly better, and treatment satisfaction was significantly higher in the test than in the control cohort (-0.02 ± 0.02 vs. -0.03 ± 0.03, p = 0.029; 70.2% vs. 55.4%, p = 0.045, respectively). In the multivariate logistic regression analysis, patients treated with the LBP program tended to be more satisfied than those treated with the conventional program, independent of age, sex, and diagnosis (adjusted odds ratio = 2.34, p = 0.012). Postoperative management with the LBP program could reduce pain more effectively and aid spine surgeons in achieving higher overall satisfaction after minimally invasive lumbar decompression, without additional pharmacological therapy.

10.
Materials (Basel) ; 14(18)2021 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-34576506

RESUMEN

We report the critical current density (Jc) and vortex pinning properties in single crystals of a novel iron-based superconductor (IBS) KCa2Fe4As4F2 with large Jc in the pristine state, before and after introduction of artificial defects by swift-particle irradiation. The effects of 2.6 GeV U and 3 MeV proton irradiations in KCa2Fe4As4F2 single crystals on transition temperature Tc and Jc, including its dose dependence, are systematically studied. Jc~8 MA/cm2 under a self-field at 2 K in the pristine crystal is strongly enhanced up to 19.4 and 17.5 MA/cm2 by irradiation of 2.6 GeV U-ions and 3 MeV protons, respectively. Suppression of Tc and dose dependence of Jc in KCa2Fe4As4F2 is different from that in a representative IBS of (Ba,K)Fe2As2, which can be explained by considering the presence of embedded defects in pristine KCa2Fe4As4F2. The vortex dynamics in the pristine and proton irradiated KCa2Fe4As4F2 single crystals are also investigated from the analyses of the field dependence of Jc and the normalized magnetic relaxation rate. In addition to the contribution of embedded defects, weak collective pinning is considered for comprehensive analyses. Vortex dynamics in KCa2Fe4As4F2 is similar to those in (Ba,K)Fe2As2 to some extent, and different from that in anisotropic Li0.8Fe0.2OHFeSe. Large anisotropy, due to the presence of insulating blocking layers in KCa2Fe4As4F2, which leads to much lower irreversibility field (Hirr) compared with 122-type IBSs, strongly affect the vortex dynamics.

11.
Spine (Phila Pa 1976) ; 46(18): 1218-1225, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34435984

RESUMEN

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To compare the clinical outcomes 5 years after minimally invasive posterior decompression for lumber spinal stenosis (LSS) between patients with and without degenerative spondylolisthesis (DS). SUMMARY OF BACKGROUND DATA: Indications for surgical procedures for patients with LSS and DS are still under investigation. Since minimally invasive surgery does not affect most anatomical structures, preoperative DS may not negatively affect the clinical outcomes of minimally invasive posterior decompression. METHODS: Overall, 198 patients with LSS who underwent microendoscopic or microscopic decompression and were followed up for more than 5 years postoperatively were included in the present study. Patients who showed a segmental kyphosis >5° at the surgical level during flexion were treated with fusion surgery. However, other patients, including those with DS, were treated with posterior decompression. The patients were divided into two groups: the DS group included 82 patients with >3-mm slip and the non-DS group included 112 patients with ≤3-mm slip or without slip. A mixed-effects model adjusted for age and sex was used to compare the improvements in the visual analog scale score for low-back pain and the Japanese Orthopaedic Association score of the two groups. For subgroup analysis (n = 53), the changes in the preoperative physical component summary and the mental component summary of Short Form-36 of the two groups at 5 years after surgery were evaluated. RESULTS: There was no significant difference in the improvement of preoperative low-back pain visual analog scale score and Japanese Orthopaedic Association score 5 years after surgery between the two groups. Subgroup analysis showed no significant difference between the two groups in the improvement of preoperative physical component summary and mental component summary 5 years after surgery. CONCLUSION: After carefully eliminating patients with segmental instability, DS did not affect the clinical outcomes of minimally invasive decompression surgery.Level of Evidence: 3.


Asunto(s)
Estenosis Espinal , Espondilolistesis , Descompresión Quirúrgica , Humanos , Vértebras Lumbares/cirugía , Estudios Retrospectivos , Estenosis Espinal/cirugía , Espondilolistesis/cirugía , Resultado del Tratamiento
12.
J Phys Ther Sci ; 32(8): 510-515, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32884172

RESUMEN

[Purpose] This study evaluated subjective posture recognition by physiotherapists with expertise in posture, examined the quantification of posture using a three-dimensional (3D) motion capture, and described posture-based characteristics. [Participants and Methods] We photographed good, normal, and bad postures in 12 participants using an infrared camera, and the resultant data were analyzed. [Results] We observed the largest displacement from a good to a bad posture in the tenth thoracic vertebra on the X-axis in the anterior-posterior direction in comparison with other index points. Further, we observed considerable differences between good and bad postures compared with other index points. Moreover, we noted significant differences between the amount of displacement between good to a normal posture and from a good to a bad posture. The vertical displacement of the Z-axis was smaller than other index points. [Conclusion] Th10 captured features from the three postures. The X-axis was displaced most between good and bad postures. Further, the amount of displacement on the Z-axis was less between good and bad posture, rendering it difficult to capture features. Therefore, the findings reported herein can be used to compare the front and rear directions of the X-axis for capturing postural changes.

13.
Biochem Biophys Res Commun ; 532(2): 185-189, 2020 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-32859379

RESUMEN

We previously reported that Escherichia coli strains carrying a firefly luciferase reporter gene (luc+) showed a posttranslationally-generated bioluminescence burst upon entry into the stationary phase. In this paper, we studied the mechanism underpinning this burst by using a series of "Keio" gene deletion strains. When luc+ driven by the lac gene promoter (lacp::luc+) was introduced into a group of Keio strains, the resulting reporter strains showed significantly altered timing and/or sizes of the burst. Remarkably, a reporter strain that lacked phosphoglucose isomerase (PGI), which catalyzes the second step of glycolysis, showed no burst, while the onset of the stationary phase of this strain was the same as that of the wild-type (WT) reporter strain. Consistently, the WT reporter strain showed no burst, when grown on arabinose or xylose instead of glucose as the carbon source. These results suggest that a process in carbohydrate metabolism is involved in the mechanism of generation of the burst. We measured temporal changes in intracellular NADPH concentrations but could not detect a significant increase or decrease relative to the occurrence of the burst. Functional implications and possible applications of the burst are discussed.


Asunto(s)
Metabolismo de los Hidratos de Carbono , Escherichia coli/genética , Escherichia coli/metabolismo , Adenosina Trifosfatasas/genética , Adenosina Trifosfatasas/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Benzotiazoles/farmacología , Metabolismo de los Hidratos de Carbono/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Eliminación de Gen , Genes Reporteros , Glucosa-6-Fosfato Isomerasa/genética , Glucosa-6-Fosfato Isomerasa/metabolismo , Glucólisis/fisiología , Luciferasas/genética , Luciferasas/metabolismo , Mediciones Luminiscentes , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , NADP/metabolismo
14.
IEEE Trans Image Process ; 27(9): 4571-4584, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29993578

RESUMEN

We propose a method of using a focal stack, i.e., a set of differently focused images, as the input for a novel light field display called a "tensor display." Although this display consists of only a few light attenuating layers located in front of a backlight, it can be viewed from many directions (angles) simultaneously without the resolution of each viewing direction being sacrificed. Conventionally, a transmittance pattern is calculated for each layer from a light field, namely, a set of dense multi-view images (typically dozens) that are to be observed from different directions. However, preparing such a massive amount of images is often cumbersome for real objects. We developed a method that does not require a complete light field as the input; instead, a focal stack composed of only a few differently focused images is directly transformed into layer patterns. Our method greatly reduces the cost of acquiring data while also maintaining the quality of the output light field. We validated the method with experiments using synthetic light field datasets and a focal stack acquired by an ordinary camera.

15.
J Magn Reson Imaging ; 2018 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-29493823

RESUMEN

BACKGROUND: Synovitis, which is a hallmark of rheumatoid arthritis (RA), needs to be precisely quantified to determine the treatment plan. Time-intensity curve (TIC) shape analysis is an objective assessment method for characterizing the pixels as artery, inflamed synovium, or other tissues using dynamic contrast-enhanced MRI (DCE-MRI). PURPOSE/HYPOTHESIS: To assess the feasibility of our original arterial mask subtraction method (AMSM) with mutual information (MI) for quantification of synovitis in RA. STUDY TYPE: Prospective study. SUBJECTS: Ten RA patients (nine women and one man; mean age, 56.8 years; range, 38-67 years). FIELD STRENGTH/SEQUENCE: 3T/DCE-MRI. ASSESSMENT: After optimization of TIC shape analysis to the hand region, a combination of TIC shape analysis and AMSM was applied to synovial quantification. The MI between pre- and postcontrast images was utilized to determine the arterial mask phase objectively, which was compared with human subjective selection. The volume of objectively measured synovitis by software was compared with that of manual outlining by an experienced radiologist. Simple TIC shape analysis and TIC shape analysis combined with AMSM were compared in slices without synovitis according to subjective evaluation. STATISTICAL TESTS: Pearson's correlation coefficient, paired t-test and intraclass correlation coefficient (ICC). RESULTS: TIC shape analysis was successfully optimized in the hand region with a correlation coefficient of 0.725 (P < 0.01) with the results of manual assessment regarded as ground truth. Objective selection utilizing MI had substantial agreement (ICC = 0.734) with subjective selection. Correlation of synovial volumetry in combination with TIC shape analysis and AMSM with manual assessment was excellent (r = 0.922, P < 0.01). In addition, negative predictive ability in slices without synovitis pixels was significantly increased (P < 0.01). DATA CONCLUSIONS: The combination of TIC shape analysis and image subtraction reinforced with MI can accurately quantify synovitis of RA in the hand by eliminating arterial pixels. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018.

16.
Br J Radiol ; 89(1061): 20151000, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26942294

RESUMEN

OBJECTIVE: To improve on the reproducibility and sensitivity of the assessment of patients with rheumatoid arthritis (RA), two semi-automated measurement methods of the area of enhancing pannus (AEP), based on thresholding (AEP_THRES) and pixel-by-pixel time-intensity curve analysis (AEP_TIC), were evaluated as an alternative for the gold-standard manual contouring method (AEP_MANUAL). METHODS: 8 patients (7 females and 1 male) with RA of the wrist or finger joints participated in the study. A three-dimensional contrast-enhanced dynamic sequence was used at 3 T. After identifying the most relevant time-intensity curve (TIC) shape in terms of synovitis by comparing with the synovitis score using the RA-MRI scoring system, three different approaches for measuring the AEP were performed. Spearman's test of rank correlation was used to compare AEPs via two semi-automated methods (AEP_THRES and AEP_TIC) against manual segmentation (AEP_MANUAL) in the entire hand region as well as the wrist and the finger regions. RESULTS: The TIC shape of "washout after fast initial enhancement" had excellent correlation with synovitis score (r = 0.809). The correlation coefficient between AEP_TIC and AEP_MANUAL was evaluated to be better than that of AEP_THRES and AEP_MANUAL in the wrist region (AEP_THRES: r = 0.716, AEP_TIC: r = 0.815), whereas these were of comparable accuracy for the entire hand and the finger regions. CONCLUSION: This study suggests that TIC analysis may be an alternative to manual contouring for pannus quantification and provides important clinical information of the extent of the disease in patients with RA. ADVANCES IN KNOWLEDGE: TIC shape analysis can be applied for new quantitative assessment for RA synovitis in the wrist.


Asunto(s)
Artritis Reumatoide/patología , Interpretación de Imagen Asistida por Computador/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética , Sinovitis/patología , Adulto , Anciano , Artritis Reumatoide/complicaciones , Medios de Contraste , Femenino , Dedos/patología , Mano/patología , Humanos , Imagenología Tridimensional , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sinovitis/complicaciones , Articulación de la Muñeca/patología
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