Vascular Supply of the Metacarpophalangeal Joint

OBJECTIVE: To describe in detail the arterial vasculature of metacarpophalangeal joints 2–5 on cadaver specimens and to compare it to ultrasound imaging of healthy subjects. METHODS: Eighteen hands of donated human cadavers were arterially injected and investigated with either corrosion casting or cryosectioning. Each layer of cryosectioned specimens was photographed in high-resolution. Images were then segmented for arterial vessels of the metacarpophalangeal (MCP) joints 2–5. The arterial pattern of the joints was reconstructed from the segmented images and from the corrosion cast specimens. Both hands of ten adult healthy volunteers were scanned focusing on the vasculature of the same joints with high-end ultrasound imaging, including color Doppler. Measurements were made on both cryosectioned arteries and Doppler images. RESULTS: The arterial supply of MCP joints 2–5 divides into a metacarpal and a phalangeal territory, respectively. The metacarpal half receives arteries from the palmar metacarpal arteries or proper palmar digital arteries, while the phalangeal half is supplied by both proper and common palmar digital arteries. Comparing anatomical and ultrasonographic results, we determined the exact anatomic location of normal vessels using Doppler images acquired of healthy joints. All, except three branches, were found with less than 50% frequency using ultrasound. Doppler signals were identified significantly more frequently in MCP joints 2–3 than on 4–5 (p < 0.0001). Similarly, Doppler signals differed in the number of detectable small, intraarticular vessels (p < 0.009), but not that of the large extraarticular ones (p < 0.1373). When comparing measurements acquired by ultrasound and on cadaver vessels, measurements using the former technique were found to be larger in all joints (p < 0.0001). CONCLUSION: Using morphological and ultrasonographic techniques, our study provides a high-resolution anatomical maps and an essential reference data set on the entire arterial vasculature of healthy human MCP 2–5 joints. We found that Doppler signal could be detected in less than 50% of the vessels of healthy volunteers except three locations. Intraarticular branches were detected with ultrasound imaging significantly more frequently on healthy MCP 2–3 joints, which should be taken into account when inflammatory and normal Doppler signals are evaluated. Our study also provides reference data for future, higher-resolution imaging techniques

Synovitis maps for the assessment of inflammatory diseases of the hand

Objectives: To compare accuracy and review times of FLASH-MRI-derived synovitis maps (SM) with conventional MR images (cMRI) in the assessment of articular synovitis and tenosynovitis of the hand. Methods: 80 hands in 40 patients (mean age, 48years; range, 15-72years) were assessed for synovitis on cMRI and SM by two readers independently. Reporting times and diagnostic confidence (scale: 1 = least, 5 = most confident) were measured. Results from an assessment of a panel of senior musculoskeletal radiologists served as the standard of reference. Results: Sensitivity and specificity for the detection of articular synovitis were 0.91/1.00 (R1) and 1.00/0.67 (R2) on cMRI and 0.87/0.75 (R1) and 0.91/0.45 (R2) on SM and for the detection of tenosynovitis 0.95/0.63 (R1) and 0.67/0.79 (R2) on cMRI and 0.67/0.89 (R1) and 0.38/1.00 (R2) on SM. Mean review times (cMRI/SM, sec) were 142/37 (R1) and 167/25 (R2). Mean diagnostic confidence (cMRI/SM) was 3.7/3.4 (R1) and 3.2/3.5 (R2) for articular synovitis and 4.0/4.0 (R1), 3.3/3.7 (R2) for tenosynovitis. Conclusion: Synovitis maps provide a comparable diagnostic accuracy to conventional MR images in the assessment of articular synovitis and tenosynovitis of the hand. Because of short review times, synovitis maps provide a fast overview of locations with synovial enhancemen

Biometric Systems

Biometric authentication has been widely used for access control and security systems over the past few years. The purpose of this book is to provide the readers with life cycle of different biometric authentication systems from their design and development to qualification and final application. The major systems discussed in this book include fingerprint identification, face recognition, iris segmentation and classification, signature verification and other miscellaneous systems which describe management policies of biometrics, reliability measures, pressure based typing and signature verification, bio-chemical systems and behavioral characteristics. In summary, this book provides the students and the researchers with different approaches to develop biometric authentication systems and at the same time includes state-of-the-art approaches in their design and development. The approaches have been thoroughly tested on standard databases and in real world applications

UWOMJ Volume 63, Number 2, Spring 1994

Schulich School of Medicine & Dentistryhttps://ir.lib.uwo.ca/uwomj/1240/thumbnail.jp

Effect of intra-articular administration of superparamagnetic iron oxide nanoparticles (SPIONs) for MRI assessment of the cartilage barrier in a large animal model

<div><p>Early diagnosis of cartilage disease at a time when changes are limited to depletion of extracellular matrix components represents an important diagnostic target to reduce patient morbidity. This report is to present proof of concept for nanoparticle dependent cartilage barrier imaging in a large animal model including the use of clinical magnetic resonance imaging (MRI). Conditioned (following matrix depletion) and unconditioned porcine metacarpophalangeal cartilage was evaluated on the basis of fluorophore conjugated 30 nm and 80 nm spherical gold nanoparticle permeation and multiphoton laser scanning and bright field microscopy after autometallographic particle enhancement. Consequently, conditioned and unconditioned joints underwent MRI pre- and post-injection with 12 nm superparamagnetic iron oxide nanoparticles (SPIONs) to evaluate particle permeation in the context of matrix depletion and use of a clinical 1.5 Tesla MRI scanner. To gauge the potential pro-inflammatory effect of intra-articular nanoparticle delivery co-cultures of equine synovium and cartilage tissue were exposed to an escalating dose of SPIONs and IL-6, IL-10, IFN-γ and PGE₂ were assessed in culture media. The chemotactic potential of growth media samples was subsequently assessed in transwell migration assays on isolated equine neutrophils. Results demonstrate an increase in MRI signal following conditioning of porcine joints which suggests that nanoparticle dependent compositional cartilage imaging is feasible. Tissue culture and neutrophil migration assays highlight a dose dependent inflammatory response following SPION exposure which at the imaging dose investigated was not different from controls. The preliminary safety and imaging data support the continued investigation of nanoparticle dependent compositional cartilage imaging. To our knowledge, this is the first report in using SPIONs as intra-articular MRI contrast agent for studying cartilage barrier function, which could potentially lead to a new diagnostic technique for early detection of cartilage disease.</p></div

A study of the use of combined thermal and microwave modelling of body regions for microwave thermography

Microwave thermography has been used for the objective assessment of inflammation in the knee joints and wrist and finger joints of patients suffering with rheumatoid arthritis by comparison with similar information obtained from a control group of subjects. Combined microwave and thermal modelling has been used to estimate the effective blood supply to the anterior intra-articular region of the patella, and the perfusion of the quadriceps muscle in both groups. 2-D numerical modelling was compared with results obtained using 1-D modelling. Microwave thermography has also been used for the detection of breast cancer. However, problems such as high false positive detection rates have occurred due to natural cyclical breast temperature changes. The thermal behaviour of the normal breast throughout the menstrual cycle has been investigated and it is shown that microwave thermography is capable of detecting temperature variations in the female breast corresponding to the ovulatory and luteal phase of the menstrual cycle. Combined microwave and thermal modelling estimated the effective perfusion of the normal breast to be in the range 0.2 - ˜ 2 kg m-3s-1. This is consistent with previous work. Microwave thermography is a quick, simple technique which clinicians can easily use. It is non-invasive, passive and causes the patient no distress. By using combined microwave and thermal modelling it is possible to estimate tissue blood perfusions and water contents and compare them with expected values. The technique has many potential applications and will hopefully find a secure niche in clinical medicine