Fine needle aspiration cytology: an in vitro study of cell yield

To investigate the effect of needle size and number of passes into a tumour mass on the cell yield from a fine needle aspirate, an in vitro study was undertaken in 19 consecutive tumours removed surgically for biopsy. Different needle sizes (23G, 21G, 19G) passed in random order, five, ten and fifteen times into the tumours, were compared. The type of tumour, needle size and number of passes independently and significantly influenced cell yield. A 21G(green) needle passed into the tumour at least 10 times was the most efficient in obtaining cells. This in vitro study could explain the variation in the reported accuracy of fine needle aspiration cytology from groups using different techniques and is perhaps one reason why the highest diagnostic accuracy and the lowest rate of unsatisfactory aspirates comes from a centre which uses a 21G needle and at least 10 passes through the tumour.     

Rediscovery and redefinition of Malcolm Smith's Trimeresurus kanburiensis in Thailand, with a report of envenoming.

Three specimens of an apparently rare pit viper, Trimeresurus kanburiensis, previously known only from the holotype collected in 1928, were found near Kanchanaburi in western Thailand. One of the snakes had bitten a young woman on the foot. She experienced severe local pain, swelling that involved the whole of the bitten limb and beyond, local bruising, recurrent shock, peripheral leucocytosis and a mild coagulopathy, but she recovered despite the lack of specific treatment. The severity of envenoming augurs ill for a young or debilitated patient bitten by this species. During the last 20 years, the name T. kanburiensis has been used incorrectly for the medically more important species, T. purpureomaculatus. Conversely, the name T. purpureomaculatus has been misapplied to specimens of a species of viper from southern Thailand which we consider very similar to T. kanburiensis, but for which a new specific name, 'T. venustus', has been suggested recently. The rediscovery and redefinition of T. kanburiensis should prevent further confusion.     

Ageing and comorbidity among low-income psychiatric outpatients

The objective of this study was to determine if non-psychiatric morbidity increases with age in a group of low-income psychiatric outpatients. Data on demographics, presenting complaints, DSM-III diagnoses and use of psychiatric services were collected on all individuals (N = 382) admitted to a psychiatric outpatient clinic serving low-income population. Non-psychiatric morbidity was identified on the basis of medical history, physical examination, and laboratory investigations. Bivariate analyses were done to determine the significance of the associations of comorbidity with other variables. A logistic regression was done using the presence or absence of comorbidity as the dependent variable. Age was the only variable which was significantly predictive of comorbidity. Additional resources should be allocated for the diagnosis and treatment of comorbidity among low-income elderly.     

Concordance between routine interictal magnetoencephalography and simultaneous scalp electroencephalography in a sample of patients with epilepsy.

Both electroencephalography (EEG) and magnetoencephalography (MEG) localize epileptiform activity but may yield different results. This discordance may arise from different detection capabilities or from different data collection and interpretation techniques. Comparisons of MEG and EEG have focused on detection of individual spikes. However, side-by-side comparisons of results as used in the clinical setting is lacking. In this report, we present our empirical comparison. We reviewed 58 simultaneous MEG-EEG recordings (35 paired-sensors, 23 whole-head) from a diverse epilepsy population, comparing previous clinical MEG interpretations with new blinded EEG interpretations, noting lobar concordance of readers' judgments of regional abnormalities. A second-pass unblinded analysis, using all available clinical data, assessed the relative contribution and plausibility of the results of each technique. Concordance was high (85%) overall. Discordance was sometimes caused by constraints imposed by MEG dipole fitting techniques. Even when results of the techniques did not match, MEG often disambiguated the clinical scenario, especially when combined with imaging information. Thoughtful analysis of combined MEG-EEG datasets, beyond algorithm-based interictal spike detection, can help guide clinical decision-making even when concordance between techniques is imperfect. In some cases, EEG and MEG are synergistic and provide complementary information.     

Evaluation of 188 consecutive homografts implanted in pulmonary position after 20 years.

OBJECTIVE: Homografts are considered the gold standard for right ventricular outflow tract reconstruction. Their long-term durability is limited, and alternatives became available. We evaluate their long-term hemodynamic performance to permit comparisons with alternative devices. METHODS: Between 1985 and 2004, 188 homografts were implanted in pulmonary position at our institution. Mean patient age was 24.8 years (range 2 days-75 years); 56 were female and 132 male. Total follow-up time was 1073 years. Fifty-eight percent were Ross procedures (mean age 31.5 years) and 42% were different procedures (mean age 15.6 years); main diagnoses were tetralogy of Fallot (48%), truncus arteriosus (14%), transposition of the great arteries (11%). Twenty-six percent were redo implantations. We evaluated freedom from death, explantation, insufficiency, relevant gradient, degeneration, and the interval between diagnosis of degeneration and therapeutic procedure (therapeutic gap). Results were stratified by indication, age, history, homograft size, and origin. RESULTS: Ten-year-freedom-from explantation was 82% in homografts >19 mm and 45% in smaller ones. Ten-year freedom from degeneration was 68% after Ross procedure and 25% after other operations; it was 83% in patients older than 10 years at implantation and 51% in younger ones. 'Non-Ross-procedure' and 'implantation age below 10 years' were the only independent risk factors for degeneration. The observed trend towards therapeutical gap reduction was not statistically significant. CONCLUSIONS: Homograft implantation in the pulmonary position can be performed with good long-term freedom from explantation. However, freedom from degeneration is a matter of concern. Therefore, alternative valved conduits are required especially for pediatric patients.     

Mental object rotation in Parkinson's disease.

Deficits in visual-spatial ability can be associated with Parkinson's disease (PD), and there are several possible reasons for these deficits. Dysfunction in frontal-striatal and/or frontal-parietal systems, associated with dopamine deficiency, might disrupt cognitive processes either supporting (e.g., working memory) or subserving visual-spatial computations. The goal of this study was to assess visual-spatial orientation ability in individuals with PD using the Mental Rotations Test (MRT), along with other measures of cognitive function. Non-demented men with PD were significantly less accurate on this test than matched control men. In contrast, women with PD performed similarly to matched control women, but both groups of women did not perform much better than chance. Further, mental rotation accuracy in men correlated with their executive skills involving mental processing and psychomotor speed. In women with PD, however, mental rotation accuracy correlated negatively with verbal memory, indicating that higher mental rotation performance was associated with lower ability in verbal memory. These results indicate that PD is associated with visual-spatial orientation deficits in men. Women with PD and control women both performed poorly on the MRT, possibly reflecting a floor effect. Although men and women with PD appear to engage different cognitive processes in this task, the reason for the sex difference remains to be elucidated.