A mathematical formula to estimate in vivo thyroid volume from two-dimensional ultrasonography

BACKGROUND: The determination of thyroid volume (TV) is required for the management of thyroid diseases. Since two-dimensional ultrasonography (2D-US) has become the accepted method for the assessment of TV (2D-US-TV), we verified whether it accurately assesses postsurgical measured TV (PS-TV). METHODS: In 92 patients who underwent total thyroidectomy by conventional cervicotomy, 2D-US-TV obtained by the ellipsoid volume formula was compared to PS-TV, determined by the Archimedes' principle. RESULTS: Mean 2D-US-TV (23.9 +/- 14.8 mL) was significantly lower than mean PS-TV (33.4 +/- 20.1 mL). Underestimation was observed in 77% of cases, and it was related to gland multinodularity and/or nodular involvement of the isthmus, while 2D-US-TV matched the PS-TV in the remaining 21 cases (23%). A mathematical formula, to estimate PS-TV from US-TV, was derived using a linear model (Calculated-TV = [1.24 x 2D-US-TV]+ 3.66). Calculated-TV (mean value 33.4 +/- 18.3 mL) significantly (p < 0.01) increased from 21 (23%) to 31 (34%) of the cases that matched PS-TV. In addition, it significantly (p < 0.01) decreased from 77% to 27% the percentage of cases where PS-TV was underestimated as well as the range of the disagreement from 245% to 92%. CONCLUSIONS: This study shows that 2D-US does not provide an accurate estimation of TV and suggests that it can be improved by a mathematical model different from the ellipsoid model. If confirmed in prospective studies, this may contribute to a more appropriate management of thyroid diseases.     

Prevalence of virulent Helicobacter pylori strains in patients affected by idiopathic dysrhythmias

Helicobacter pylori virulent strains have been shown to affect cardiovascular diseases through molecular mimicry mechanisms. Silent autoimmune myocarditis has been hypothesized to be the cause of idiopathic dysrhythmias (IA). The aim of this study is to assess the prevalence of virulent H. pylori strains in patients affected by IA. In this study,54 patients (40 men, mean age 44 ± 17 years) affected by IA and 50 healthy subjects (34 men, mean age 45 ± 9) were evaluated. IA, defined as dysrhythmias with no evidence of other cardiac pathology, were either supraventricular (SVA, 23 patients; mean age 45 ± 15 years) or ventricular (VA, 31 patients; mean age 42 ± 18 years). H. pylori infection and gastrointestinal (GI) symptoms were evaluated. H. pylori strains expressing the cytotoxin-associated gene A (cagA) and the vacuolating-cytotoxin A (vacA) were also assessed through western blot. The prevalence of H. pylori is similar in IA patients and in controls (42 vs. 44%; p > 0.05); H. pylori infection is observed in 48 and 39% of the patients are affected by SVA and VA, respectively. The prevalence of CagA-positive strains is increased in IA patients compared to controls (65 vs. 42%; p < 0.01); similarly, the prevalence of VacA-positive strains is also increased in IA patients (74 vs. 46%; p < 0.006). Excluding belching, infected patients did not show any difference in GI symptoms, when compared to non-infected subjects. From this study it is concluded that there is an epidemiological link between CagA and VacA-positive H. pylori strains in IA patients.     

Imaging modalities for evaluation of the spine

The spine can be evaluated by a number of different imaging modalities. Although magnetic resonance imaging has assumed the dominant role in the diagnosis of spinal disease, the individual clinical situation still determines the procedure of choice. This review discusses the different imaging techniques and their currently accepted indications.     

Complications of pelvic resections

The authors report on complications that occurred with 63 pelvic resections. There were 43 complications: 13 infections, seven cases of nerve palsy, 12 cases of vascular or visceral damage, six mechanical and five aesthetic complications. Infection and vascular and visceral damage were more frequent in anterior arch resections, neurological damage in iliac wing resections, and mechanical complications in periacetabular resections. The treatment and outcome of the complications are reported.     

Effect of urinary bladder outlet obstruction on the rabbit ureter

Ureters of mature New Zealand white male rabbits were studied at 7 and 14 days following partial bladder outlet obstruction. Muscarinic receptor density; intracellular concentrations of DNA, RNA, lipid, and hydroxyproline; and functional characteristics of the whole ureter were assessed as a means of characterizing the ureteral secondary response to partial bladder obstruction. Wet weight increased 2-fold by day 7 and almost to 3-fold by day 14. Ureteral length increased 15% by day 7 and 29% by day 14. DNA concentration varied only slightly from controls while RNA increased by 68% by day 7 but returned to near normal range by day 14. Total hydroxyproline content increased, although hydroxyproline concentration per mg tissue decreased. Total lipids increased by 73% over the first 7 days but subsequently decreased to 27% above control levels by day 14. After 1 week of obstruction, muscarinic receptor density was 35.5% of controls, and after 2 weeks of obstruction, muscarinic density was 52.5% of controls. Although muscarinic receptor density decreased significantly, the number of receptors per ureter did not substantially change. Flow studies demonstrated increased opening pressures at 7 days and decreased opening pressures by day 14. Flow as a function of constant pressure was not significantly changed by the 7th day but increased 24% by the 14th day. Bethanechol (muscarinic agonist) caused similar decreases in flow in control and 1- and 2-week obstructed ureters. These studies indicate that 1 week following partial outlet obstruction, ureters demonstrate increased protein synthesis and lipid deposition resulting in increased weight and length. By the 2nd week, protein synthesis and lipid content begin to return to normal. Weight and length remain significantly increased and the capacity for flow through the ureter improves.