Qualitative ultrasound training: defining the learning curve.

AIM: To assess the developing competence of two trainees learning groin and shoulder ultrasound when compared to an expert practitioner. MATERIALS AND METHODS: Specific pro formas were used to record ultrasound trainee performance in each scan region and their diagnosis was compared to the opinion of the expert. The data derived were reviewed using kappa analysis and training end points were defined as a minimum 80% trainee agreement with the expert. Retrospectively, cumulative sum analysis was applied to the data to assess case-by-case performance. RESULTS: For groin hernias, reporting an average of 70 examinations was required to become competent and inguinal hernias required higher numbers of examinations than femoral hernias. For shoulders, an average of 80 examinations was required and the supraspinatus and infraspinatus tendons proved the most challenging structures. CONCLUSIONS: Kappa analysis demonstrated a differential in the learning curves for individual structures within each examination region. Sequential kappa scores are consistent with a sigmoid learning curve. The numbers required to achieve satisfactory agreement are suggested as required minima for ultrasound training curricula. Cumulative sum analysis provided a sensitive indicator of trainee performance, quickly highlighting individual learning difficulties when they arose. Its prospective use can ensure extra training support is instigated quickly and appropriately.

Benign hidradenoma: magnetic resonance and ultrasound features of two cases.

Tumors of sweat gland origin are rare in the hand but should be considered in the differential diagnosis when certain imaging features are present. We present a case of nodular hidradenoma of the hand, with previously unreported magnetic resonance imaging features, and a further case in the thigh, both with ultrasound and histopathological correlation. The imaging literature of this tumor is reviewed, and its significance is discussed with respect to the current understanding of its malignant potential.

Posterior dislocation of the long head of biceps tendon: case report and review of the literature.

Posterior or lateral dislocation of the long head of biceps is a rare complication of shoulder dislocation that can result in inability to relocate the humerus. The diagnosis should be suspected when certain radiographic features are present at the initial presentation. Other imaging modalities can aid diagnosis when clinical management is unsuccessful or protracted. We present a case of surgically proven posterior dislocation of the biceps tendon with conventional radiographic, computed tomography and magnetic resonance imaging assessment. The literature on this subject is reviewed, and imaging features associated with the diagnosis are described.

Appraisal of compliance with the UICC/AJCC staging system in the staging of gastric cancer. Union Internacional Contra la Cancrum/American Joint Committee on Cancer.

BACKGROUND: In the surgical management of gastric carcinoma, regional lymphatic spread is of prognostic importance. The fifth edition of the Union Internacional Contra la Cancrum classification has been shown to be reproducible, practical and of significant prognostic use. The tumour node metastasis (TNM) system requires at least 15 lymph nodes to be acquired and examined for staging to be accurate. This has raised concern over the consistency with which the requisite numbers of nodes would be acquired. This study was performed to assess how consistently surgically managed cases of gastric cancer in the West Midlands fulfilled this requirement to allow accurate staging. METHODS: Data from the West Midlands Cancer Intelligence Unit on all cases of gastric cancer registered from 1998 to 1999 were obtained and the number of lymph nodes documented for each surgically managed case was assessed. RESULTS: Overall, only 31.0 per cent of surgically resected cases could be assessed accurately according to the TNM system. The proportion staged accurately varied widely across hospitals from 10.9 to 76.0 per cent. CONCLUSION: These results reflect the need for improved N staging across the region to aid the appropriate multimodal treatment of patients.

Molecular cloning of a cyclic GMP-stimulated cyclic nucleotide phosphodiesterase cDNA. Identification and distribution of isozyme variants.

We have cloned a 4.2-kilobase pair (kb) cDNA that encodes the cyclic GMP-stimulated phosphodiesterase (cGS PDE) from a bovine adrenal cortex library. The 921-residue polypeptide deduced from the cDNA nucleotide sequence is nearly identical with the complete amino acid sequence of the cGS PDE purified from a soluble bovine heart extract. Moreover, PPD-S49 cells transfected with the cGS PDE cDNA express a soluble cAMP hydrolytic activity that is enhanced by cGMP. Total RNA isolated from several bovine tissues were screened for cGS PDE transcript by Northern blot analysis. The cGS PDE cDNA appears to hybridize to a single 4.5-4.6-kb mRNA species. Although the cGS PDE mRNA is most abundant in the adrenal cortex, it is also concentrated in the adrenal medulla and heart and in anatomically distinct regions of the brain and kidney. A mRNA species encoding a putative variant cGS PDE isoform was detected by RNase protection. Total RNA isolated from adrenal cortex, adrenal medulla, liver, kidney, trachea, lung, spleen, and T-lymphocytes completely protected a 452-base riboprobe encoding 100 residues of the adrenal cortex cGS PDE amino terminus. In contrast, RNAs isolated from brain (cerebral cortex, hippocampus, and basal ganglia) protected only 268 bases of this riboprobe. The RNase protection pattern of this same probe using heart RNA showed major bands at both 268 and 452 bases, suggesting that two different cGS PDE mRNA species are expressed. These results indicate that the cGS PDE is widely expressed in a variety of tissues. Moreover, these studies suggest that at least one different cGS PDE isoform having a structurally distinct amino-terminal domain is expressed in brain and heart.

Identification of a noncatalytic cGMP-binding domain conserved in both the cGMP-stimulated and photoreceptor cyclic nucleotide phosphodiesterases.

Partial amino acid sequence has been determined for the cone, alpha' subunit of the bovine photoreceptor cyclic nucleotide phosphodiesterase (PDE) and deduced from nucleotide sequences of a partial cDNA clone. These sequences identify the alpha' subunit as the product of a gene that is distinct from those encoding the alpha or beta subunits of the membrane-associated rod photoreceptor PDE. Comparisons between the recently determined cGMP-stimulated-PDE sequence and those of the alpha and alpha' photoreceptor PDE subunits reveal an unexpected sequence similarity. In addition to the catalytic domain conserved in eukaryotic PDEs, all three PDEs possess a second conserved segment of approximately 340 residues that contains two internally homologous repeats. Limited proteolysis and direct photolabeling studies indicate that the noncatalytic, cGMP-binding site(s) in the cGMP-stimulated PDE is located within this conserved domain, suggesting that it also may serve this function in the photoreceptor PDEs. Moreover, other PDEs that do not bind cGMP at noncatalytic sites do not contain this conserved domain. The function of the conserved segment in the photoreceptor PDEs is not known, but the homology to allosteric sites of the cGMP-stimulated PDE suggests a role in cGMP binding and modulation of enzyme activity.