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1.
J Orthop Surg (Hong Kong) ; 32(2): 10225536241268607, 2024.
Article in English | MEDLINE | ID: mdl-39054928

ABSTRACT

PURPOSE: To perform a quantitative analysis of the amount of cancellous bone in the distal radius and olecranon process by segmentation of computed tomographic scans. As a secondary analysis, the bone density by Hounsfield units was evaluated at the same sites. METHODS: Computed tomography angiography images of the upper extremity were analyzed using 3-D Slicer™ medical imaging software. Bone volume (cm3) and density (Hounsfield units) from the cancellous bone between the distal radius and the olecranon process were compared by creating an advanced three-dimensional model. The images were analyzed in duplicate, and an intraclass correlation was performed to assess measurement consistency. RESULTS: Twenty subjects were included. A total volume of 5.01 ± 1.21 cm3 and 5.81 ± 1.61 cm3 for the distal radius and the olecranon process (p < .0001), respectively, was found. Regarding Hounsfield units, the density of the olecranon process was 303.1 ± 73.26, and the distal radius was 206.5 ± 63.73 (p < .0001). All intraclass correlation coefficients were >0.992. CONCLUSION: These results suggest that the olecranon process has a greater volume and a higher bone mineral density than the distal radius. With these results, the surgeon will have the ability to decide the quantity and quality of bone grafts according to the surgical procedure.


Subject(s)
Bone Density , Imaging, Three-Dimensional , Radius , Tomography, X-Ray Computed , Humans , Radius/diagnostic imaging , Radius/surgery , Male , Female , Middle Aged , Adult , Tomography, X-Ray Computed/methods , Olecranon Process/diagnostic imaging , Olecranon Process/surgery , Bone Transplantation/methods , Aged , Upper Extremity/surgery , Upper Extremity/diagnostic imaging , Cancellous Bone/diagnostic imaging , Cancellous Bone/transplantation
3.
Clin Radiol ; 79(9): 657-664, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38945792

ABSTRACT

A range of abnormalities may acutely affect the upper limb (UL) extremity vasculature including trauma, peripheral vascular disease, and inflammatory conditions. Significant technical advances in computed tomography angiography (CTA) have led to the widespread adoption of this noninvasive modality for rapid evaluation of UL arterial abnormalities in the emergency department setting. A key advantage of CTA over traditional digital subtraction angiography (DSA) is the ability to evaluate concurrent osseous and soft tissue injuries. Accurate identification of pathology requires knowledge of normal UL arterial anatomy in addition to a high-quality study, which may be achieved with a robust CTA protocol. We describe the spectrum of imaging findings on upper limb CTA associated with various acute presentations. Traumatic vascular injuries may occur secondary to penetrating and blunt aetiologies appearing on CTA as contrast extravasation, pooling, pseudoaneurysm, occlusion, and arteriovenous fistula. Peripheral vascular disease manifests as atherosclerotic plaques with thready downstream opacification, and these may precipitate acute thromboembolic events. Inflammatory conditions affecting the UL vasculature includes large and small vessel vasculitides characterised by arterial mural thickening. The use of modalities, including ultrasound and magnetic resonance angiography (MRA), should be considered for further characterisation where appropriate.


Subject(s)
Computed Tomography Angiography , Emergency Service, Hospital , Upper Extremity , Humans , Computed Tomography Angiography/methods , Upper Extremity/blood supply , Upper Extremity/diagnostic imaging
4.
Muscle Nerve ; 70(3): 302-305, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38938077

ABSTRACT

Total supported abduction, or TSA, is a position for ultrasound evaluations and guided interventions of the upper extremity. It provides optimal access to the medial arm through the volar wrist and palmar hand for diagnostic evaluations of the median and ulnar nerves as well as procedures including injections for carpal tunnel syndrome, ulnar neuropathy at the elbow, and stenosing tenosynovitis. It enables ease of both ipsilateral and bilateral evaluations/interventions without the need for significant positional changes by the patient or physician. Incorporation of TSA may enhance clinical efficiency by reducing the amount of time, materials, and space required to provide such services.


Subject(s)
Ultrasonography , Upper Extremity , Humans , Upper Extremity/diagnostic imaging , Ultrasonography/methods , Patient Positioning/methods , Carpal Tunnel Syndrome/diagnostic imaging , Ulnar Nerve/diagnostic imaging
5.
Surg Radiol Anat ; 46(9): 1469-1479, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38874605

ABSTRACT

PURPOSE: For basic training in ultrasonography (US), medical students and residents must learn cross-sectional anatomy. However, the present educational material is not sufficient to learn the sectional anatomy for US. This study aimed to provide a criterion for reading ambiguous structures on US images of upper limb through the sectioned images of Visible Korean. METHODS: US images of the right arm of a volunteer were scanned (28 planes). For comparison with US images, the sectioned images of the right upper limb (24 bits color, 0.5 mm intervals, 0.06 mm × 0.06 mm sized pixel) were used. After the volume model was constructed from the sectioned images using MRIcroGL, new sectioned images of 28 planes corresponding to the US images of 28 planes were created by adjusting the slope of the volume model. In all images, the anatomical terms of 59 structures from the shoulder to the fingers were annotated. RESULTS: In the atlas, which consists of 28 sets of US images and sectioned images of various slope planes, 59 structures of the shoulder, arm, elbow, wrist, palm, and fingers were observed in detail. CONCLUSION: We were able to interpret the ambiguous structures on the US images using the sectioned images with high resolution and actual color. Therefore, to learn the cross-sectional anatomy for US, the sectioned images from the Visible Korean project were deemed to be the suitable data because they contained all human gross anatomical information.


Subject(s)
Anatomy, Cross-Sectional , Ultrasonography , Upper Extremity , Humans , Upper Extremity/diagnostic imaging , Upper Extremity/anatomy & histology , Ultrasonography/methods , Visible Human Projects , Republic of Korea , Color , Male
6.
Curr Med Imaging ; 20: e15734056281665, 2024.
Article in English | MEDLINE | ID: mdl-38545766

ABSTRACT

INTRODUCTION: Neurolymphomatosis (NL) is a rare disease. Ultrasound (US) plays a crucial role in diagnosing and following up the NL. CASE PRESENTATION: A 59-year-old man was hospitalized with acute pain in the left upper extremity. Ultrasound revealed segmental swelling of multiple nerves around his left elbow with abundant blood flow signals. Contrast-Enhanced Ultrasound (CEUS) showed a rapid, complete and homogenous enhancement in the nerve lesions in the early arterial phase. The NL was confirmed by imaging and flow cytometry, and he accepted chemotherapy. The posttherapeutic ultrasound showed that the nerves in the left upper limb were basically normal. Unfortunately, the patient died of cerebral metastasis in 5 months. CONCLUSION: The nerve US and CEUS can show specific manifestations and provide more diagnostic information about NL.


Subject(s)
Upper Extremity , Male , Humans , Middle Aged , Follow-Up Studies , Ultrasonography/methods , Upper Extremity/diagnostic imaging
7.
Radiography (Lond) ; 30(3): 753-758, 2024 May.
Article in English | MEDLINE | ID: mdl-38432174

ABSTRACT

INTRODUCTION: Injuries to extremities are a common presentation to emergency departments and may be associated with multiple abnormalities. Patients may be referred for X-ray imaging of multiple adjacent regions, but the diagnostic outcomes of these X-ray examinations have not been fully explored. The aim of this study was to assess the diagnostic efficacy of X-ray examinations of adjacent body regions in the upper limb. METHODS: Upper limb X-rays examinations performed over six months were collected from two hospitals, and all patients who had adjacent regions X-rayed were included. Using the radiology reports as a reference standard, the diagnostic yield of these additional adjacent X-ray examinations was assessed. Descriptive statistics and Pearson's Chi Square were used for data analysis. RESULTS: 591 patients had 1455 X-ray examinations, ranging from two to six X-ray requests. More than 80% of X-ray examinations were due to an injury, but less than 60% had symptoms mentioned in the clinical history. Overall, 39.1% of initial examinations reported a new finding but only 1.5% of all subsequent imaging had a new abnormality detected. Examinations with symptoms specified in the clinical history were more likely to detect new findings (p=<0.001). CONCLUSION: Imaging is an essential diagnostic tool in medical settings, but all radiographic tests should be justified, and adjacent imaging has a low diagnostic yield, hence, all limbs should be carefully assessed individually to assess the need for imaging. Every request should be justified based on presentation and symptoms, particularly when multiple areas may be impacted. IMPLICATIONS FOR PRACTICE: Radiographic imaging is easily accessible but adherence to guidelines and assessing the diagnostic yield of common examinations is important to ensure benefits to patients.


Subject(s)
Upper Extremity , Humans , Female , Male , Upper Extremity/diagnostic imaging , Middle Aged , Adult , Radiography , Aged , Adolescent , Retrospective Studies , Young Adult , Aged, 80 and over
9.
Radiography (Lond) ; 30(3): 745-752, 2024 May.
Article in English | MEDLINE | ID: mdl-38428199

ABSTRACT

INTRODUCTION: Dynamic techniques should be used to compliment static imaging in the field of Musculoskeletal ultrasound. Performing limb movements and imaging simultaneously, allows for diagnosing certain musculoskeletal conditions not otherwise confirmed by still images. This article aims to provide guidance on how to perform a selection of these dynamic musculoskeletal ultrasound techniques with a focus on the upper limb. METHODS: This pictorial guide features techniques gathered from literature review and experience gained in the field. RESULTS: Application of dynamic ultrasound techniques has been evidenced in the literature to diagnose conditions such as trigger finger, dislocating tendons and causes of peripheral neuropathy. CONCLUSION: Musculoskeletal conditions only elicited during limb movement can be difficult to diagnose. Appropriate use of dynamic techniques increases likelihood of correct diagnosis of the described conditions. IMPLICATIONS FOR PRACTICE: Ultrasound provides a unique opportunity to visualise these conditions thus ultrasound users should aim to familiarise themselves with dynamic ultrasound techniques to improve patient outcomes.


Subject(s)
Musculoskeletal Diseases , Ultrasonography , Upper Extremity , Humans , Ultrasonography/methods , Upper Extremity/diagnostic imaging , Musculoskeletal Diseases/diagnostic imaging
10.
Bull Hosp Jt Dis (2013) ; 82(1): 53-59, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38431978

ABSTRACT

Ultrasound technologies are infrequently utilized in orthopedics as a first line diagnostic method, however, advances in technology and the applied techniques have opened the door for how and when ultrasound can be used. One specific avenue is the use of point of care ultrasound in which ultrasound is used at the time of initial patient evaluation by the evaluating physician. This use expedites time to diagnosis and can even guide therapeutic interventions. In the past two decades there have been numerous studies demonstrating the effectiveness of ultrasound for the diagnosis of many orthopedic conditions in the upper extremity, often demonstrating that it can be used in the place of and with greater diagnostic accuracy than magnetic resonance imaging. This review elaborates on these topics and lays a groundwork for how to incorporate point of care ultrasound into a modern orthopedic practice.


Subject(s)
Musculoskeletal Diseases , Orthopedic Procedures , Humans , Point-of-Care Systems , Ultrasonography , Upper Extremity/diagnostic imaging
11.
Semin Musculoskelet Radiol ; 28(2): 180-192, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38484770

ABSTRACT

Increase in youth sports participation, longer duration of play, and earlier starting points have increased the prevalence of acute and repetitive overuse musculoskeletal injuries. This rise in injury rates has led to increased efforts to better understand the susceptible sites of injury that are unique to the growing immature skeleton. Upper extremity injuries are currently the best studied, particularly those that occur among pediatric baseball players and gymnasts. The weak link in skeletally immature athletes is the growth plate complex that includes those injuries located at the epiphyseal and apophyseal primary physes and the peripherally located secondary physes. This article reviews the anatomy and function of these growth plate complexes, followed by a discussion of the pathophysiologic mechanisms, spectrum of imaging findings, and existing evidence-based guidelines for injury prevention and return to play.


Subject(s)
Athletic Injuries , Baseball , Humans , Adolescent , Child , Athletic Injuries/diagnostic imaging , Return to Sport , Upper Extremity/diagnostic imaging , Upper Extremity/injuries , Athletes , Radiologists , Baseball/injuries
13.
Hand Surg Rehabil ; 43(2): 101636, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38215880

ABSTRACT

Ultrasound elastography is a recently developed method for accurate measurement of soft tissue stiffness in addition to the clinician's subjective evaluation. The present review briefly describes the ultrasound elastography techniques and outlines clinical applications for tendon, muscle, nerve, skin and other soft tissues of the hand and upper limb. Strain elastography provides a qualitative evaluation of the stiffness, and shear-wave elastography generates quantitative elastograms superimposed on a B-mode image. The stiffness in degenerative tendinopathy and/or tendon injury was significantly lower than in a normal tendon in several studies. Elastography is also a reliable method to evaluate functional muscle activity, compared to conventional surface electromyography. The median nerve is consistently stiffer in patients with carpal tunnel syndrome than in healthy subjects, on whatever ultrasound elastography technique. Elastography distinguishes normal skin from scars and can be used to evaluate scar severity and treatment. Elastography has huge clinical applications in musculoskeletal tissues. Continued development of systems and increased training of clinicians will expand our knowledge of elastography and its clinical applications in the future.


Subject(s)
Elasticity Imaging Techniques , Humans , Upper Extremity/diagnostic imaging , Upper Extremity/physiopathology , Hand/diagnostic imaging , Hand/physiopathology , Carpal Tunnel Syndrome/diagnostic imaging , Carpal Tunnel Syndrome/physiopathology , Muscle, Skeletal/diagnostic imaging , Muscle, Skeletal/physiopathology , Tendons/diagnostic imaging , Tendon Injuries/diagnostic imaging , Tendon Injuries/physiopathology , Cicatrix/diagnostic imaging , Cicatrix/physiopathology
14.
Top Stroke Rehabil ; 31(5): 501-512, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38194359

ABSTRACT

BACKGROUND: After stroke, the effects of focused scapulo-humeral training with simultaneous assessment of the changes in shoulder subluxation, related muscle thicknesses and upper limb performance have not been studied in the literature. OBJECTIVES: This study aimed to investigate the effects of an 8-week scapulo-humeral training program in addition to conventional rehabilitation on upper extremity/trunk functions, shoulder pain, and sonographic measurements of the shoulder joint and periscapular muscles. METHODS: Thirty stroke individuals were randomly separated into two groups as Group I-scapulo-humeral training (5F/10 M) and Group II - control (5F/10 M). Conventional rehabilitation program was applied to both groups, and a scapulo-humeral training exercise protocol was added for the scapulo-humeral group. All the treatments were applied for 1 hour/day, 3 days/week, 8 weeks. Clinical evaluations were made using the Fugl Meyer Assessment-Upper Extremity(FMA-UE), Action Research Arm Test(ARAT), ABILHAND, Visual Analog Scale, and Trunk Impairment Scale(TIS). Ultrasound was used to measure serratus anterior/lower trapezius muscle thicknesses, and acromion-greater tubercule/acromio-humeral distances. RESULTS: FMA-UE, ARAT, ABILHAND and TIS scores increased in both groups, with greater increases in most parameters in the scapulo-humeral training group. Shoulder pain decreased only in the scapulo-humeral training group. Subacromial distances were decreased on the paretic side, and muscle thicknesses increased on both sides in the scapulo-humeral training group, and in the control group, only serratus anterior muscle thickness increased on the paretic side (p < 0.05 for all). CONCLUSIONS: Additional scapulo-humeral exercises to conventional rehabilitation was seen to improve upper extremity/trunk performance and shoulder pain, and to increase scapula stabilizer muscle thicknesses in stroke individuals with mild-moderate upper extremity disability.


Subject(s)
Exercise Therapy , Stroke Rehabilitation , Stroke , Ultrasonography , Humans , Male , Female , Stroke Rehabilitation/methods , Middle Aged , Stroke/diagnostic imaging , Stroke/physiopathology , Aged , Exercise Therapy/methods , Muscle, Skeletal/diagnostic imaging , Muscle, Skeletal/physiopathology , Shoulder Pain/rehabilitation , Shoulder Pain/diagnostic imaging , Shoulder Pain/etiology , Upper Extremity/physiopathology , Upper Extremity/diagnostic imaging , Adult , Scapula/diagnostic imaging , Scapula/physiopathology , Treatment Outcome
15.
Magn Reson Imaging ; 107: 24-32, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38181836

ABSTRACT

PURPOSES: Non-contrast magnetic resonance lymphography (NMRL) has recently shown the capability of evaluating anatomical fluid distribution in upper extremity lymphedema (UEL). However, there is still a lack of knowledge about the correlation between the characteristic three-dimensional (3D) NMRL findings and the indocyanine green lymphography (ICG-L) findings. Our goal was to clarify the relationship between the 3D NMRL findings and the ICG-L findings. METHODS: Medical charts of patients with secondary UEL who underwent NMRL and ICG-L between January 2018 to October 2021 were reviewed. The upper extremities were divided into 6 regions; the hand, elbow, and the radial and ulnar aspects of the forearm and the upper arm. We investigated the prevalence of characteristic 3D NMRL patterns (Mist/Spray/Inky) in each region based on the ICG-L stage. We also examined the association between the 3D NMRL stage which we proposed and the ICG-L stage, and other clinical factors. RESULTS: A total of 150 regions of 25 patients with upper extremities lymphedema were enrolled in the study. All of the characteristic patterns increased significantly as the ICG-L stage advanced (p < 0.001, < 0.001, and < 0.001, respectively). The predominant NMRL patterns changed significantly from the Early pattern (Mist pattern) to the Advanced pattern (Inky/Spray pattern) as the ICG-L stage progressed (p < 0.001). The higher Stage of 3D NMRL was significantly associated with the progression of the ICG-L stage (rs = 0.80, p < 0.001). CONCLUSIONS: Characteristic 3D NMRL patterns and the 3D NMRL Stage had a significant relationship with the ICG-L stage and other clinical parameters. This information may be an efficient tool for a more precise and objective evaluation of various treatments for UEL patients.


Subject(s)
Lymphedema , Lymphography , Humans , Lymphography/methods , Retrospective Studies , Indocyanine Green , Lymphedema/diagnostic imaging , Upper Extremity/diagnostic imaging , Magnetic Resonance Spectroscopy
16.
IEEE Trans Biomed Eng ; 71(4): 1161-1169, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37922169

ABSTRACT

Surface electromyography (sEMG) is currently the primary method for user control of prosthetic manipulation. Its inherent limitations of low signal-to-noise ratio, limited specificity and susceptibility to noise, however, hinder successful implementation. Ultrasound provides a possible alternative, but current systems with medical probes are expense, bulky and non-wearable. This work proposes an innovative prosthetic control strategy based on a piezoelectric micromachined ultrasound transducer (PMUT) hardware system. Two PMUT-based probes were developed, comprising a 23×26 PMUT array and encapsulated in Ecoflex material. These compact and wearable probes represent a significant improvement over traditional ultrasound probes as they weigh only 1.8 grams and eliminate the need for ultrasound gel. A preliminary test of the probes was performed in non-disabled subjects performing 12 different hand gestures. The two probes were placed perpendicular to the flexor digitorum superficialis and brachioradialis muscles, respectively, to transmit/receive pulse-echo signals reflecting muscle activities. Hand gesture was correctly predicted 96% of the time with only these two probes. The adoption of the PMUT-based strategy greatly reduced the required number of channels, amount of processing circuit and subsequent analysis. The probes show promise for making prosthesis control more practical and economical.


Subject(s)
Artificial Limbs , Humans , Ultrasonography , Signal-To-Noise Ratio , Transducers , Upper Extremity/diagnostic imaging
17.
CJEM ; 26(4): 228-231, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38060159

ABSTRACT

Ultrasound-guided nerve blocks (UGNBs) are becoming a more common method for pain control in the emergency department. Specifically, brachial plexus blocks have shown promise for acute upper extremity injuries as well as an alternative to procedural sedation for glenohumeral reductions. Unfortunately, there is minimal discussion in the EM literature regarding phrenic nerve paralysis (a well-known complication from brachial plexus blocks). The anatomy of the brachial plexus, its relationship to the phrenic nerve, and why ultrasound-guided brachial plexus blocks can cause phrenic nerve paralysis and resultant respiratory impairment will be discussed. The focus on patient safety is paramount, and those with preexisting respiratory conditions, extremes of age or weight, spinal deformities, previous neck injuries, and anatomical variations are at greater risk. We put forth different block strategies for risk mitigation, including patient selection, volume and type of anesthetic, block location, postprocedural monitoring, and specific discharge instructions. Understanding the benefits and risks of UGNBs is critical for emergency physicians to provide effective pain control while ensuring optimal patient safety.


Subject(s)
Brachial Plexus Block , Humans , Brachial Plexus Block/methods , Ultrasonography, Interventional/methods , Emergency Service, Hospital , Paralysis , Upper Extremity/diagnostic imaging , Upper Extremity/injuries , Upper Extremity/innervation , Pain , Anesthetics, Local
18.
J Surg Res ; 293: 613-617, 2024 01.
Article in English | MEDLINE | ID: mdl-37837816

ABSTRACT

INTRODUCTION: Lymphoscintigraphy (LS) helps identify drainage to interval (epitrochlear or popliteal) lymph node basins for extremity melanomas. This study evaluated how often routine LS evaluation identified an interval sentinel lymph node (SLN) and how often that node was found to have metastasis. METHODS: A single institution, retrospective study identified patients with an extremity melanoma who underwent routine LS and SLN biopsy over a 25-y period. Comparisons of factors associated with the identification of interval node drainage and tumor status were made. RESULTS: In 634 patients reviewed, 5.7% of patients drained to an interval SLN. Of those biopsied, 29.2% were positive for micrometastases. Among patients with biopsies of both the traditional and interval nodal basins, nearly 20% had positive interval nodes with negative SLNs in the traditional basin. Sex, age, thickness, ulceration, and the presence of mitotic figures were not predictive of identifying an interval node on LS, nor for having disease in an interval node. Anatomic location of the primary melanoma was the only identifiable risk factor, as no interval nodes were identified in melanomas of the thigh or upper arm (P ≤ 0.001). CONCLUSIONS: Distal extremity melanomas have a moderate risk of mapping to an interval SLN. Routine LS should be considered in these patients, especially as these may be the only tumor-positive nodes. However, primary extremity melanomas proximal to the epitrochlear or popliteal nodal basins do not map to interval nodes, and improved savings and workflow could be realized by selectively omitting routine LS in such patients.


Subject(s)
Lymphadenopathy , Melanoma , Sentinel Lymph Node , Skin Neoplasms , Humans , Sentinel Lymph Node/diagnostic imaging , Sentinel Lymph Node/pathology , Lymphoscintigraphy , Retrospective Studies , Lymphatic Metastasis/diagnostic imaging , Lymphatic Metastasis/pathology , Radionuclide Imaging , Skin Neoplasms/diagnostic imaging , Skin Neoplasms/surgery , Skin Neoplasms/pathology , Melanoma/diagnostic imaging , Melanoma/surgery , Melanoma/pathology , Lymph Nodes/pathology , Sentinel Lymph Node Biopsy , Upper Extremity/diagnostic imaging , Lymph Node Excision , Melanoma, Cutaneous Malignant
19.
Magn Reson Med ; 91(2): 773-783, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37831659

ABSTRACT

PURPOSE: DTI characterizes tissue microstructure and provides proxy measures of nerve health. Echo-planar imaging is a popular method of acquiring DTI but is susceptible to various artifacts (e.g., susceptibility, motion, and eddy currents), which may be ameliorated via preprocessing. There are many pipelines available but limited data comparing their performance, which provides the rationale for this study. METHODS: DTI was acquired from the upper limb of heathy volunteers at 3T in blip-up and blip-down directions. Data were independently corrected using (i) FSL's TOPUP & eddy, (ii) FSL's TOPUP, (iii) DSI Studio, and (iv) TORTOISE. DTI metrics were extracted from the median, radial, and ulnar nerves and compared (between pipelines) using mixed-effects linear regression. The geometric similarity of corrected b = 0 images and the slice matched T1-weighted (T1w) images were computed using the Sörenson-Dice coefficient. RESULTS: Without preprocessing, the similarity coefficient of the blip-up and blip-down datasets to the T1w was 0·80 and 0·79, respectively. Preprocessing improved the geometric similarity by 1% with no difference between pipelines. Compared to TOPUP & eddy, DSI Studio and TORTOISE generated 2% and 6% lower estimates of fractional anisotropy, and 6% and 13% higher estimates of radial diffusivity, respectively. Estimates of anisotropy from TOPUP & eddy versus TOPUP were not different but TOPUP reduced radial diffusivity by 3%. The agreement of DTI metrics between pipelines was poor. CONCLUSIONS: Preprocessing DTI from the upper limb improves geometric similarity but the choice of the pipeline introduces clinically important variability in diffusion parameter estimates from peripheral nerves.


Subject(s)
Diffusion Magnetic Resonance Imaging , Diffusion Tensor Imaging , Humans , Diffusion Tensor Imaging/methods , Diffusion Magnetic Resonance Imaging/methods , Peripheral Nerves , Upper Extremity/diagnostic imaging , Echo-Planar Imaging , Image Processing, Computer-Assisted/methods
20.
Sensors (Basel) ; 23(18)2023 Sep 12.
Article in English | MEDLINE | ID: mdl-37765897

ABSTRACT

Digital representations of anatomical parts are crucial for various biomedical applications. This paper presents an automatic alignment procedure for creating accurate 3D models of upper limb anatomy using a low-cost handheld 3D scanner. The goal is to overcome the challenges associated with forearm 3D scanning, such as needing multiple views, stability requirements, and optical undercuts. While bulky and expensive multi-camera systems have been used in previous research, this study explores the feasibility of using multiple consumer RGB-D sensors for scanning human anatomies. The proposed scanner comprises three Intel® RealSenseTM D415 depth cameras assembled on a lightweight circular jig, enabling simultaneous acquisition from three viewpoints. To achieve automatic alignment, the paper introduces a procedure that extracts common key points between acquisitions deriving from different scanner poses. Relevant hand key points are detected using a neural network, which works on the RGB images captured by the depth cameras. A set of forearm key points is meanwhile identified by processing the acquired data through a specifically developed algorithm that seeks the forearm's skeleton line. The alignment process involves automatic, rough 3D alignment and fine registration using an iterative-closest-point (ICP) algorithm expressly developed for this application. The proposed method was tested on forearm scans and compared the results obtained by a manual coarse alignment followed by an ICP algorithm for fine registration using commercial software. Deviations below 5 mm, with a mean value of 1.5 mm, were found. The obtained results are critically discussed and compared with the available implementations of published methods. The results demonstrate significant improvements to the state of the art and the potential of the proposed approach to accelerate the acquisition process and automatically register point clouds from different scanner poses without the intervention of skilled operators. This study contributes to developing effective upper limb rehabilitation frameworks and personalized biomedical applications by addressing these critical challenges.


Subject(s)
Forearm , Upper Extremity , Humans , Upper Extremity/diagnostic imaging , Hand , Algorithms , Neural Networks, Computer
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