Palpable prostatic nodules: comparison of US and digital guidance for fine-needle aspiration biopsy

This study was undertaken to evaluate the use of transrectal sonographically guided fine-needle aspiration biopsy and to compare sonographic with digital guidance for biopsy. In 62 patients in whom prostatic carcinoma was suspected at digital rectal examination, fine-needle aspiration biopsies were performed transperineally under sonographic guidance and transrectally under digital guidance. These patients had 89 nodules, 73 of which were sampled with both techniques. Malignant cells were obtained under digital guidance in 17 of 73 nodules (23%) and under sonographic guidance in 16 (22%). An additional seven nodules, which were not seen sonographically, were sampled under digital guidance and proved to be negative. In nine other nodules that were nonpalpable and evident only with sonography, malignant cells were obtained under sonographic guidance in three. These findings indicate that sonographic guidance for fine-needle aspiration biopsy is as good as digital guidance for palpable lesions.     

Pharmacokinetics in obese patients

One of the many problems in providing anaesthesia for morbidlyobese patients is the influence of obesity on pharmacokineticsand pharmacodynamics. Drug administration in obese patientsis difficult because recommended doses are based on pharmacokineticdata obtained from individuals with normal weights; therefore,mistakes in the determination of the appropriate dose are oftenmade. Because of comorbidity in these patients, the functionof organs involved in drug elimination (e.g. kidney, liver)can be affected making pharmacokinetics more difficult and complex.     

Chemical and biomechanical characterization of hyperhomocysteinemic bone disease in an animal model

Background

Classical homocystinuria is an autosomal recessive disorder caused by cystathionine β-synthase (CBS) deficiency and characterized by distinctive alterations of bone growth and skeletal development. Skeletal changes include a reduction in bone density, making it a potentially attractive model for the study of idiopathic osteoporosis.

Methods

To investigate this aspect of hyperhomocysteinemia, we supplemented developing chicks (n = 8) with 0.6% dl-homocysteine (hCySH) for the first 8 weeks of life in comparison to controls (n = 10), and studied biochemical, biomechanical and morphologic effects of this nutritional intervention.

Results

hCySH-fed animals grew faster and had longer tibiae at the end of the study. Plasma levels of hCySH, methionine, cystathionine, and inorganic sulfate were higher, but calcium, phosphate, and other indices of osteoblast metabolism were not different. Radiographs of the lower limbs showed generalized osteopenia and accelerated epiphyseal ossification with distinct metaphyseal and suprametaphyseal lucencies similar to those found in human homocystinurics. Although biomechanical testing of the tibiae, including maximal load to failure and bone stiffness, indicated stronger bone, strength was proportional to the increased length and cortical thickness in the hCySH-supplemented group. Bone ash weights and IR-spectroscopy of cortical bone showed no difference in mineral content, but there were higher Ca²⁺/PO₄^3- and lower Ca²⁺/CO₃^2- molar ratios than in controls. Mineral crystallization was unchanged.

Conclusion

In this chick model, hyperhomocysteinemia causes greater radial and longitudinal bone growth, despite normal indices of bone formation. Although there is also evidence for an abnormal matrix and altered bone composition, our finding of normal biomechanical bone strength, once corrected for altered morphometry, suggests that any increase in the risk of long bone fracture in human hyperhomocysteinemic disease is small. We also conclude that the hCySH-supplemented chick is a promising model for study of the connective tissue abnormalities associated with homocystinuria and an important alternative model to the CBS knock-out mouse.

     

Morphine-augmented cholescintigraphy with a false-negative result and an apparent ectopic gallbladder.

Morphine-augmented cholescintigraphy has been shown to be a highly sensitive and specific means of evaluating acute cholecystitis. False-negative results do occur infrequently, however, and such a case is reported. In addition, this case initially demonstrated an apparent ectopic gallbladder, and thus anomalies in location of the gallbladder will be discussed.     

Hyperdense middle cerebral artery sign on CT: efficacy in detecting middle cerebral artery thrombosis

The hyperdense middle cerebral artery sign is a CT predictor of the development of a large cerebral infarct. The limits of detectability were tested in a blinded, then unblinded analysis of CT scans from 25 acute stroke patients. In the initial blinded analysis, sign detection exhibited the following mean values: sensitivity, 78.5%; specificity, 93.4%; positive predictive value, 66%; negative predictive value, 96.4%; accuracy, 91.3%. Kappa statistics analysis indicated poor interobserver agreement (k = .38). Results of unblinded analysis were as follows: sensitivity, 69%; specificity, 94.4%; positive predictive value, 82.8%; negative predictive value, 88.7%; accuracy, 87.3%. There was fair unblinded interobserver agreement (k = .53). Unblinded analysis had a lower false-positive frequency and did not increase the number of true-positive determinations. We conclude that detection of the hyperdense middle cerebral artery sign on CT scans by multiple observers is a sensitive, accurate, and predictive indicator of middle cerebral artery thromboembolism.