ObjectiveTo introduce a new bone defect model based on the anatomical measurement of radius and ulna in rabbits for offering a standard model for further tissue engineering research.
MethodsFifteen healthy 4-month-old New Zealand rabbits were selected for anatomic measurement and radiological measurement of the radius and ulna. Another 30 healthy 4-month-old New Zealand rabbits were randomly divided into groups A, B, and C (n=10). The radius bone defect was created bilaterally in 3 groups. In group A, the periosteum and interosseous membranes were fully removed with jig-saw by approach between extensor carpi radialis muscle and musculus extensor digitorum. The periosteum and interosseous membranes were fully removed in group B, and only periosteum was removed in group C with electric-saw by approach between extensor carpi radialis muscle and flexor digitorum profundus based on anatomical analysis results of ulnar and radial measurement. The gross observation, X-ray, micro-CT three-dimensional reconstruction, bone mineral density (BMD), and bone mineral content (BMC) were observed and recorded at immediate and 15 weeks after operation. HE staining and Masson staining were performed to observe bone formation in the defect areas.
ResultsBlood vessel injury (1 rabbit), tendon injury (2 rabbits), postoperative hematoma (1 rabbit), and infection (1 rabbit) occurred in group A, postoperative infection (1 rabbit) in group C, and no postoperative complications in group B; the complication rate of group A (50%) was significantly higher than that of groups B (0%) and C (10%) (P<0.05). The radiological examination showed bone defects were fully repaired in groups A and B at 15 weeks, but bridging callus formation was observed in group C. There was no significant difference in BMC and BMD among 3 groups (P>0.05). HE staining and Masson staining results showed bone formation in group A, with structure disturbance and sclerosis. New bone formed in groups B and C, cartilage cells were observed in the center of bone cells.
ConclusionThe radius bone defect model established by approach between extensor carpi radialis muscle and flexor digitorum profundus is an ideal model because of better exposures, less intra-operative blood loss, less complications. Interosseous membranes play a role in bone tissue repair process, and the mechanism needs further study.
The velocity of blood in vessels is an important indicator that reflects the microcirculatory status. The core of the measurement technology, which is based on spatiotemporal (ST) image, is to map the cell motion trace to the two-dimensional ST image, and transfer the measurement of flow velocity to the detection of trace orientation in ST image. This paper proposes a trace orientation measurement algorithm is based on Randomized Hough Transformation and projection transformation, and it is able to estimate trace orientation and flow velocity in noisy ST images. Experiments showed that the agreement between the results by manual and by the proposed algorithm reached over 90%.
Objective To recognize the different phases of Korotkoff sounds through deep learning technology, so as to improve the accuracy of blood pressure measurement in different populations. Methods A classification model of the Korotkoff sounds phases was designed, which fused attention mechanism (Attention), residual network (ResNet) and bidirectional long short-term memory (BiLSTM). First, a single Korotkoff sound signal was extracted from the whole Korotkoff sounds signals beat by beat, and each Korotkoff sound signal was converted into a Mel spectrogram. Then, the local feature extraction of Mel spectrogram was processed by using the Attention mechanism and ResNet network, and BiLSTM network was used to deal with the temporal relations between features, and full-connection layer network was applied in reducing the dimension of features. Finally, the classification was completed by SoftMax function. The dataset used in this study was collected from 44 volunteers (24 females, 20 males with an average age of 36 years), and the model performance was verified using 10-fold cross-validation. Results The classification accuracy of the established model for the 5 types of Korotkoff sounds phases was 93.4%, which was higher than that of other models. Conclusion This study proves that the deep learning method can accurately classify Korotkoff sounds phases, which lays a strong technical foundation for the subsequent design of automatic blood pressure measurement methods based on the classification of the Korotkoff sounds phases.
Objective To explore the anatomical parameters of the cervical uncinate process “inflection point” through cervical CT angiography (CTA) and MRI measurements, offering a reliable and safe anatomical landmark for anterior cervical decompression surgery. Methods A retrospective analysis was conducted on the cervical CTA and MRI imaging data of normal adults who met the selection criteria between January 2020 and January 2024. The CTA dataset included 326 cases, with 200 males and 126 females, aged 22-55 years (mean, 46.7 years). The MRI dataset included 300 cases, with 200 males and 100 females, aged 18-55 years (mean, 43.7 years). Based on the CTA data, three-dimensional models of C3-C7 were constructed, and the following measurements were obtained from the superior view: uncinate process “inflection point” to vertebral artery distance (UIVD), uncinate process tip to vertebral artery distance (UTVD), uncinate process “inflection point” to “inflection point” distance (UID), uncinate process long-axis to sagittal angle (ULSA), and uncinate process “inflection point” to transverse foramen-sagittal angle (UITSA). From the anterior view, the anterior uncinate process to sagittal angle (AUSA) was measured. From the posterior view, the posterior uncinate process to sagittal angle (PUSA) was measured. Based on the MRI data, uncinate process “inflection point” to dural sac distance (UIDD) and dural sac width (DSW) were measured. The trends in measurement parameters of C3-C7 were observed, and the differences in measurement parameters between genders and between the left and right sides of the same segment were compared, as well as the difference in UID and DSW within the same segment was compared. Results The measurement parameters from C3 to C7 in the CTA data showed a general increasing trend, with no significant difference between the left and right sides within the same segment (P>0.05). The UIVD, UTVD, and UID were greater in males than in females, with significant differences observed in the UIVD and UTVD at C3 and C6 and UID at C3, C6, and C7 (P<0.05). The MRI measured DSW showed a general increasing trend from C3 to C7, and the DSW at C6 was greater in females than in males, with a significant difference (P<0.05). The UIDD showed a gradual decreasing trend, with the smallest value at C6. There was no significant difference between males and females or between the left and right sides within the same segment (P>0.05). The UID was greater than the DSW at C3-C7, and the differences were significant (P<0.05). ConclusionThe uncinate process “inflection point” is a constant anatomical structure located at the anteromedial aspect of the uncinate process tip and laterally to the dural sac. It maintains a certain safe distance from the vertebral artery. As a decompression landmark in anterior cervical spine surgery, it not only ensures surgical safety but also guarantees complete decompression.
To achieve non-contact measurement of human heart rate and improve its accuracy, this paper proposes a method for measuring human heart rate based on multi-channel radar data fusion. The radar data were firstly extracted by human body position identification, phase extraction and unwinding, phase difference, band-pass filtering optimized by power spectrum entropy, and fast independent component analysis for each channel data. After overlaying and fusing the four-channel data, the heartbeat signal was separated using frost-optimized variational modal decomposition. Finally, a chirp Z-transform was introduced for heart rate estimation. After validation with 40 sets of data, the average root mean square error of the proposed method was 2.35 beats per minute, with an average error rate of 2.39%, a Pearson correlation coefficient of 0.97, a confidence interval of [–4.78, 4.78] beats per minute, and a consistency error of –0.04. The experimental results show that the proposed measurement method performs well in terms of accuracy, correlation, and consistency, enabling precise measurement of human heart rate.
Objective To investigate and analyze the three-dimensional anatomic structure of glenoid bone in some Chinese people so as to provide the accurate anatomic data to design the new prosthesis of glenoid bone for Chinese people. Methods A total of 90 volunteers with two healthy shoulders (52 males and 38 females, aging 19-60 years with an average of 39.6 years) were selected. Five parameters were measured by use of three-dimensional computed tomography, volumerendering technique (VRT) and multiplanar reformation (MPR), including the maximum antero-posterior width (MAPW),antero-posterior radius of curvature (APROC), maximum supero-inferior height (MSIH), supero-inferior radius of curvature(SIROC) and version angle (VA) of glenoid. All parameters were measured two times, and the average values were analysed by SPSS13.0. The level of significance was set at P lt; 0.05. Results The average MAPW was (2.51 ± 0.32) cm, the average APROC was (5.50 ± 1.21) cm, the average MSIH was (3.45 ± 0.29) cm, the average SIROC was (3.98 ± 0.55) cm, and the average VA was (— 0.03 ± 4.66)°. There were no significant differences (P gt; 0.05) in MAPW, APROC, MSIH, SIROC and VA between two sides. There were significant differences (P lt; 0.05) in MAPW, MSIH, SIROC and VA, and no significant difference (P gt; 0.05) in APROC between female and male. MAPW was correlated with APROC, MAPW was correlated with MSIH, APROC was correlated with SIROC, and the correlation coefficient was 0.298, 0.495 and 0.262, respectively. Conclusion There are no significant differences in MAPW, APROC, MSIH, SIROC and VA of glenoid between two sides. There are sexual significant differences in MAPW, MSIH, SIROC and VA. The data and its statistical results may serve as guidel ines for the design of the glenoid component.
ObjectiveTo review the evaluation method of paraspinal muscle and its role in lumbar spine diseases, and offer reference for further research on paraspinal muscles.MethodsThe related literature of paraspinal muscle measurement and its role in lumbar spine diseases was reviewed. The evaluation methods of paraspinal muscle were analyzed from the advantages and disadvantages and the role of paraspinal muscle in lumbar spine diseases was summarized.ResultsRadiographic methods are often used to evaluate the atrophy of paraspinal muscle, mainly including CT and MRI. The cross-sectional area and fatty infiltration of paraspinal muscle are two key parameters. Radiographic methods are reproducible and widely applied, but CT has the disadvantage of radiation exposure, while the cost of MRI is high. Besides, more and more researchers focus on the functional evaluation of paraspinal muscle, which mainly includes surface electromyogram analysis and back muscle strength test. The surface electromyogram analysis can quantitatively measure neuromuscular function, but the results could be affected by many influencing factors. The back muscle strength test is simple, but it lacks standardized posture. The atrophy of paraspinal muscle is related to many lumbar spine diseases, while the results of different researches are different.ConclusionThere are many methods to evaluate paraspinal muscles, but there is no unified standard. The role of paraspinal muscle in lumbar spine diseases need to be further studied.
Hypertension is the primary disease that endangers human health. A convenient and accurate blood pressure measurement method can help to prevent the hypertension. This paper proposed a continuous blood pressure measurement method based on facial video signal. Firstly, color distortion filtering and independent component analysis were used to extract the video pulse wave of the region of interest in the facial video signal, and the multi-dimensional feature extraction of the pulse wave was preformed based on the time-frequency domain and physiological principles; Secondly, an integrated feature selection method was designed to extract the universal optimal feature subset; After that, we compared the single person blood pressure measurement models established by Elman neural network based on particle swarm optimization, support vector machine (SVM) and deep belief network; Finally, we used SVM algorithm to build a general blood pressure prediction model, which was compared and evaluated with the real blood pressure value. The experimental results showed that the blood pressure measurement results based on facial video were in good agreement with the standard blood pressure values. Comparing the estimated blood pressure from the video with standard blood pressure value, the mean absolute error (MAE) of systolic blood pressure was 4.9 mm Hg with a standard deviation (STD) of 5.9 mm Hg, and the MAE of diastolic blood pressure was 4.6 mm Hg with a STD of 5.0 mm Hg, which met the AAMI standards. The non-contact blood pressure measurement method based on video stream proposed in this paper can be used for blood pressure measurement.
ObjectiveTo summarize the diagnosis and measurement methods of bone defect in anterior shoulder instability (glenoid bone defect and Hill-Sachs lesion).MethodsThe related literature on the diagnosis and measurement of the bone defect in anterior shoulder instability was reviewed and summarized.ResultsThe commonly used techniques for the diagnosis of anterior glenoid bone defect and Hill-Sachs lesion of humeral head include X-ray, CT, MRI, arthroscopy, arthrography. The methods for measuring the degree of anterior glenoid bone defect include Griffith method, glenoid index method, Pico method, and best-fit circle method. The indexes for measuring the Hill-Sachs lesion include the length, width, depth, and volume. X-ray is mainly used for primary screening. Best-fit circle method on three-dimensional (3D) CT reconstruction is commonly used to measure the glenoid bone defect currently. Glenoid track theory on 3D CT reconstruction is popular in recent years. Reliability of measuring the glenoid bone defect and Hill-Sachs lesion with MRI and arthroscopy is still debatable. Arthrography is more and more used in the diagnosis of shoulder joint instability of bone defect and concomitant soft tissue injury.ConclusionHow to improve the accuracy of evaluating glenoid bone defect and Hill-Sachs lesion before surgery still need further study.
Rapid development of recently emerging precision medicine techniques represented by gene therapy has brought hope for the treatment of rare blinding eye diseases such as inherited retinal diseases (IRDs) for which there was no effective treatment previously. Although the globally growth of clinical trials for IRDs has increased rapidly over the past decade, due to the highly genetic and clinical phenotypic heterogeneity, as well as limited data on epidemiology and natural history of the disease, along with severe loss of vision function of majority patients for which the established measurements may not be appropriate, such studies lack standard outcome measurements and endpoints to asses clinical meaningful effectiveness, posing great challenges in terms of study design and evaluation of treatment efficacy, as well as clinical practice application. At present, there is no systematic nor standardized guidance on safety measures, clinical outcomes and endpoints of visual function for clinical trial design in IRDs. Therefore, in order to standardize the validated evaluation of IRDs clinical efficacy outcome measurements and endpoints, the Fundus Disease Group of Chinese Medical Association Ophthalmology Branch and Fundus Disease Committee of Chinese Medical Doctor Association Ophthalmology Branch organized domestic experts to put forward consensus and recommendations on standardizing outcome measurements and endpoints for clinical study design in IRDs, aiming to advance the study design of IRDs natural history research and clinical trials and to effectively evaluate disease progression and intervention efficacy. Along with the development of medical science and clinical trials, relevant content will be improved and updated accordingly.
