Biomedical subjects

David Connell

Publications and source records attributed to David Connell.

11 recordsLinked to original sources

PubMed2006

MR imaging findings of acetabular dysplasia in adults.

OBJECTIVE: To evaluate the diagnostic accuracy of MR imaging in the identification of labral and articular cartilage lesions in patients with acetabular dysplasia. DESIGN AND PATIENTS: Pre-operative MR imaging was performed on 27 hips in 25 consecutive patients (16 males, 9 females, age range 19-52 years, mean age 31.2 years) with radiographic evidence of acetabular dysplasia (centre-edge angle of Wiberg <20 degrees). The average duration of symptoms was 16.2 months. Two musculoskeletal radiologists assessed MR images in consensus for the presence of abnormality involving the acetabular labrum and adjacent acetabular articular cartilage. A high resolution, non-arthrographic technique was used to assess the labrum and labral chondral transitional zone. Surgical correlation was obtained in all cases by a single surgeon experienced in hip arthroscopy and ten patients with normal hip MRI were included to provide a control group. RESULTS: The acetabular labra in the dysplastic hips demonstrated abnormal signal intensity, and had an elongated appearance when compared with the control group (mean length 10.9 mm vs 6.4 mm). Morphological appearances in the labra included surface irregularity, fissures and cleft formation. MR imaging correctly identified the severity of chondral abnormality in 24 of 27 hips (89%) when compared with arthroscopic findings. CONCLUSIONS: MR imaging demonstrates an elongated labrum, focal intra-substance signal change and irregularity and fissuring of the margins in patients with acetabular dysplasia. Abnormality is also identified at the labral chondral transitional zone, where fissuring, focal clefts, chondral deficiency and subchondral cyst formation may be apparent. A high-resolution, non-arthrographic technique can provide an accurate preoperative assessment and evaluate the presence of premature osteoarthritis.

Acetabulum↗

PubMed2006

Imaging of hamstring injuries: therapeutic implications.

Though recent research into the diagnosis and management of hamstring disorders has resulted in early and accurate recognition of injury, hamstring strain remains the most common form of muscle injury in the active population. With prompt recognition of hamstring strain, an appropriate rest and rehabilitation routine may be devised by the sports clinician in the hope of avoiding future and possibly more debilitating injury. As such, imaging has played a pivotal role in assisting athletes, both elite and recreational, in returning to activity expeditiously.

Athletic Injuries↗

PubMed2006

Sonography and MRI of rectus abdominis muscle strain in elite tennis players.

OBJECTIVE: The objective of this study was to describe the imaging findings at sonography and MRI of rectus abdominis muscle strain in tennis players. CONCLUSION: Asymmetrical hypertrophy of the recti is seen in elite tennis players. The muscle belly hypertrophies on the side opposite the dominant arm and is subject to muscle tears of its deep fibers below the umbilicus. Imaging can be used to show these injuries.

Adolescent↗

PubMed2005

Magnetic resonance imaging of the hip: detection of labral and chondral abnormalities using noncontrast imaging.

PURPOSE: Traditional imaging techniques have limited ability to detect subtle chondral and labral injuries of the hip. We performed a retrospective review of patients who underwent magnetic resonance imaging (MRI) of the hip and subsequent hip arthroscopy in order to evaluate the ability of optimized, noncontrast MRI to identify tears of the acetabular labrum and defects in articular cartilage. TYPE OF STUDY: Retrospective review of a consecutive sample. METHODS: Between January 1997 and July 2000, 92 patients had MRI of the hip, followed by arthroscopic surgery of that hip by 1 of 2 surgeons (R.B., D.E.P.). Two musculoskeletal MR radiologists blinded to the initial MRI and surgical findings, independently interpreted the studies, looking for the location and degree of articular cartilage and acetabular labral pathology. RESULTS: Of the 92 patients studied, each of 2 radiologists correctly identified 83 (94%) and 84 (95%) of the 88 labral tears present at surgery, respectively. There was 92% interobserver agreement on the MRI studies. For articular cartilage defects on the femoral head and acetabulum, there was good agreement (92% and 86% within 1 grade) between MRI and surgical grading and between the 2 MR readers (kappa of 0.8 for femoral head cartilage and 0.7 for acetabular cartilage). CONCLUSIONS: This study shows that noncontrast MRI of the hip, using an optimized protocol, can noninvasively identify labral and chondral pathology. Such information may facilitate deciding which patients warrant surgical intervention, thus preserving hip arthroscopy as a therapeutic tool. LEVEL OF EVIDENCE: Level II, Development of Diagnostic Criteria Study.

Acetabulum↗

PubMed2005

Overview of the National Health Educator Competencies Update Project, 1998-2004.

The National Health Educator Competencies Update Project (CUP), conducted during 1998-2004, addressed what health educators currently do in practice, the degree to which the role definition of the entry-level health educator is still up-to-date, and the validation of advanced-level competencies. A 19-page questionnaire was sent to a representative sample of health educators in recognized practice settings in all states and the District of Columbia. A total of 4,030 health educators participated in the research (70.6% adjusted response rate) resulting in the largest national data set of its kind, with 1.6 million data points. The model derived from the research was hierarchical (7 areas of responsibility, 35 competencies, and 163 subcompetencies), with three levels of practice (Entry, Advanced 1, and Advanced 2) differentiated by degrees earned and years of experience. The findings affect professional preparation, credentialing, and professional development.

Advisory Committees↗

PubMed2004

A comparison of magnetic resonance imaging, sonography, and radiography of the hand in patients with early rheumatoid arthritis.

OBJECTIVE: As therapy for rheumatoid arthritis (RA) becomes more effective, more sensitive imaging methods are required to assess disease activity and joint damage. We compared magnetic resonance imaging (MRI), sonography, and radiography for assessment of disease activity for the detection of bony erosions. METHODS: Forty-six patients with newly diagnosed RA (onset within 2 years) received clinical and laboratory assessment followed by radiographs, sonography, and MRI of the right hand at baseline and at 6 months according to a standardized protocol. We determined the presence of edema, synovitis, effusions, tendon fluid, tendon thickening, and size in the same way by MRI and sonography. The intra- and interreader reliability of MRI and radiographs and predictors of MRI erosions at 6 month followup were also examined. RESULTS: At baseline, 39 (85%), 14 (30%), and 17 (37%) patients had erosions identified on MRI, sonography, and radiography, respectively. Over time, the percentage of patients with erosions increased to 91% for MRI, 41% for sonography, and 48% for radiography. The absolute number of erosions increased from 177 to 239 erosions for MRI, from 30 to 43 for sonography, and from 38 to 73 for radiographs. The intra- and interreader reliability for the assessment of erosions and synovitis on MRI was acceptable (intrareader ICC of 0.60 and 0.90; interreader ICC of 0.77 and 0.89, respectively). CONCLUSION: MRI appears to be the most sensitive modality for erosive disease compared with sonography and radiography. Sonography detected more joint and tendon sheath effusions than MRI in this study and therefore may have a role in the assessment of disease activity.

Adult↗

PubMed2003

Evaluation of the immortalised mouse brain capillary endothelial cell line, b.End3, as an in vitro blood-brain barrier model for drug uptake and transport studies.

Well-characterised cell lines represent important tools for the study of endogenous solute or xenobiotic transport. A brain microvascular cell line, b.End3, isolated from mice transformed with the Polyoma virus middle T-antigen is available commercially. Here we report the characterisation of some features of b.End3 of relevance to its use in blood-brain barrier transport investigations. The b.End3 cells displayed a distinctive spindle-like squamous morphology in culture. Clathrin coated pits and numerous uncoated intracellular vesicles were evident within the cells, as was the expression of the vesicle-associated proteins, clathrin, caveolin-1, flotillin and dynamin II. In the presence of C6 astroglial co-culture b.End3 monolayers achieved a maximal transendothelial electrical resistance of 130 Omega cm2, but lacked real discrimination with respect to the permeation of transcellular and paracellular probes, e.g. permeability coefficients (x 10(-6) cm s(-1)) for propranolol of approximately 23 vs. 16 for sucrose. RT-PCR analysis confirmed the presence within the b.End3 cells of mRNA transcripts for the following transporters: GLUT-1; MCT 1 and 2; OAT1; Oatp1; mdr 1a and 1b; MRP 1 and 5; beta-alanine, system L and system y+L amino acid carriers; the nucleoside transporters cNT1 and 2, eNT1 and 2, and the tight junctional elements, ZO-1, JAM, occludin, claudin-1 and -5. The b.End3 cells actively accumulated D-glucose in a sodium-independent manner with characteristics consistant with that of GLUT-1. Functionality for P-glycoprotein efflux was evident as assessed by a rhodamine-123 accumulation and retention assay. The system L LAT1/4F2hc amino acid transporter was examined through uptake of L-leucine and L-phenylalanine and provided Km and Vmax values of approximately 16 microM and 350-480 pmol/mg protein/10 min, respectively; the affinity of transport for these substrates being weaker, approximately threefold, when the b.End3 cells were grown in the presence of C6 astroglial factors. Although the b.End3 cells appear unsuitable for transendothelial permeability assessments they display characteristics that would allow their worthwhile use in studies addressing blood-brain barrier transport mechanisms.

Alkaline Phosphatase↗

PubMed2003

Evaluation of the hamstring muscle complex following acute injury.

OBJECTIVE: To evaluate the imaging findings following acute hamstring injury. DESIGN AND PATIENTS: We retrospectively reviewed the imaging findings of hamstring muscle complex (HMC) strain in 170 patients referred to our institution over a 3-year period. A total of 179 injuries to the HMC were demonstrated in 170 patients (154 male, 16 female, mean age 28.2 years). The mean duration of symptoms was 4.7 days (range 1-10 days). MR imaging was performed in 97 cases and sonography in 102 cases (both modalities were performed in 20 examinations). Attention was directed to the frequency of muscle involvement, the location of the injury within the muscle-tendon unit, the extent of the injury and discriminating avulsion from muscle injury. RESULTS AND CONCLUSIONS: Twenty-one patients had proximal tendon injury, with sixteen avulsions and five partial tears. Sixteen of these patients had surgical confirmation of hamstring avulsion from the ischial tuberosity (14 conjoint, 2 biceps femoris alone) and all were reliably diagnosed with MR imaging (16/16), but less so with sonography (7/12). Four distal tendon avulsions were also observed (three semitendinosus, one biceps femoris). With respect to muscle injury, the biceps femoris was most commonly injured (124/154). Semimembranosus was an uncommon muscle injury (21/154) and semitendinosus rare (9/154). Imaging can discriminate a hamstring tendon avulsion from musculotendinous strain and helps identify which patients necessitate surgical management as opposed to conservative treatment.

Adult↗

PubMed2003

Posterior tibiotalar ligament injury resulting in posteromedial impingement.

OBJECTIVE: To describe the imaging features of the normal anatomy and injury of the posterior tibiotalar ligament (PTTL) of the ankle in a group of patients presenting with posteromedial impingement. MATERIALS AND METHODS: Twenty-five consecutive patients underwent imaging for posteromedial ankle pain following injury. All 25 patients were investigated with MR imaging, 17 with ultrasound and 5 with radionuclide bone scanning. Clinical data and surgical findings were correlated with the results of radiological investigation. RESULTS: The PTTL demonstrated scar formation and a hypertrophic response consistent with previous injury in all 25 patients. Displacement or encasement of the surrounding tendons and their sheaths was often encountered (12/25). Bony avulsion was demonstrated in 5/25 occasions with ultrasound and 2/25 with MR imaging. Twelve patients underwent surgery, confirming the radiological findings. CONCLUSION: Imaging can effectively evaluate the integrity of the PTTL in the context of ongoing posteromedial ankle pain.

Adult↗

PubMed2002

Adhesive capsulitis: role of MR imaging in differential diagnosis.

The purpose of this study was to describe and characterize the MR imaging findings in a group of patients who underwent surgery for adhesive capsulitis. Twenty-four MR imaging studies in 24 consecutive patients with clinical evidence of adhesive capsulitis were performed prior to arthroscopic capsulotomy. There were 17 women and 7 men with a mean age of 53.5 years. Images were scrutinised for changes in the synovium particularly in the rotator interval, around the biceps anchor and axillary pouch. Intravenous gadolinium was given routinely. We also examined a control group of 22 patients who underwent the same MR imaging protocol after referral for rotator cuff pathology. Soft tissue density showing variable enhancement after gadolinium administration was visible in the rotator interval in 22 of 24 studies on MR imaging. Seventeen patients showed soft tissue density partially encasing the biceps anchor. Ten patients showed thickening and gadolinium enhancement of the axillary pouch. Three patients from the study cohort had partial tears of the supraspinatus tendon. All the patients subsequently had surgery which confirmed fibrovascular scar tissue in the rotator interval, around the biceps anchor and a variable degree of synovial inflammation of the glenohumeral capsule. Two patients from a control group with suspected rotator cuff pathology showed abnormal intensity in the rotator interval on MR imaging. Magnetic resonance imaging can identify changes in the shoulder joint that correspond to abnormalities seen at surgery. This may be useful for discriminating adhesive capsulitis from other causes of shoulder pain.

Adult↗

PubMedDate not supplied

Hamstring muscle complex: an imaging review.

Increasing activity in the general population and the high demands placed on athletes have resulted in injuries to the hamstring muscle complex (HMC) being commonplace in sports. Imaging of HMC injuries can form a considerable part of a sports medicine practice, with a wide spectrum of such injuries being reflected in their varied imaging appearances. Magnetic resonance (MR) imaging and ultrasonography (US) are the imaging modalities of choice in this setting. Both MR imaging and US provide exquisitely detailed information about the HMC with respect to localization and characterization of injury. Optimization of MR imaging involves the use of a surface coil and high-resolution techniques, allowing the musculoskeletal radiologist not only to diagnose injury and assess severity but also to provide the clinician with useful clues with respect to prognosis. The portability and availability of US make it an attractive modality for the diagnosis of acute hamstring injuries, although its effectiveness is dependent on operator experience. A thorough knowledge of the HMC anatomy and of the spectrum of imaging findings in HMC injury is crucial for providing optimal patient care and will enable the musculoskeletal radiologist to make an accurate and useful contribution to the treatment of athletes at all levels of participation.

Athletic Injuries↗