A multicenter evaluation of the appropriate use of single-photon emission tomography myocardial perfusion imaging in Greece

Background

This study evaluates the appropriate use of myocardial perfusion imaging (MPI) and determines patterns and variables associated with inappropriate testing.

Methods

Over a 10-month period data were collected prospectively from consecutive patients referred for MPI in four academic departments and an appropriate use grade was assigned (appropriate, uncertain, inappropriate, and unclassifiable scans) according to established criteria.

Results

Among 3,032 referrals appropriate MPI had 72.8% of patients and 19.2% of studies were inappropriate, the remaining being uncertain (7.2%) or unclassifiable (0.8%). In multivariate analysis the asymptomatic status (odds ratio 10.7, P < .001), good functional capacity (odds ratio 1.9, P < .001), an interpretable resting electrocardiogram (odds ratio 1.8, P = .004), an age <65 years (odds ratio 1.5, P = .001) and the absence of diabetes (odds ratio 1.7, P < .001) or dyslipidemia (odds ratio 1.3, P = .014) were independent predictors of inappropriate scintigraphy. The most common indication for inappropriate testing was the assessment of asymptomatic patients <2 years after percutaneous coronary intervention (PCI) (38.9%).

Conclusions

The appropriate use of MPI is relatively high, but a considerable proportion of inappropriate scans is noted which is associated with markers of lower risk. The most common source of inappropriate testing is the assessment of asymptomatic patients <2 years after PCI.     

Vertigo during the Epley maneuver and success rate in patients with BPPV

To investigate whether reported vertigo during the Epley maneuver predicts therapeutic success in patients with benign paroxysmal positioning vertigo of the posterior semicircular canal (pc-BPPV). Fifty consecutive adult patients with pc-BPPV, based on a positive Dix–Hallpike test (DHT), were treated with the Epley maneuver and retested after 2 days. Patients were asked to report the presence of vertigo upon assuming each of the four positions of the maneuver. Thirty seven patients (74 %) were treated successfully in one session. Twenty out of 23 patients who reported vertigo at turning the head to the opposite side (2nd position) had a negative DHT on follow-up. These patients had a higher chance of a successful outcome compared to patients who did not report vertigo in the 2nd position (Odds ratio 5.3, 95 % CI: 1.3–22.2, p = 0.022). Report of vertigo at the other positions was not associated with the outcome. Report of vertigo at the second position of a single modified Epley maneuver is associated with therapeutic success.     

Use of (99m)Tc-sulesomab for the diagnosis of prosthesis infection after total joint arthroplasty

This study aimed to evaluate the diagnostic efficacy of antigranulocyte scintigraphy using the antibody fragment (99m)Tc-sulesomab (LeukoScan) for the diagnosis of prosthesis infection in patients with total hip or knee arthroplasty. The results from 19 patients with suspected total joint arthroplasty infection who had undergone a three-phase bone scan and a subsequent examination with (99m)Tc-sulesomab during a 1-year period were reviewed. Twelve patients were shown to have prosthesis infection on culture of aspirated synovial fluid or intra-operative samples. The overall sensitivity, specificity, positive and negative predictive values, and diagnostic accuracy for (99m)Tc-sulesomab were 75%, 86%, 90%, 66% and 79%, respectively, compared with 54%, 83%, 88%, 45% and 63%, respectively, for the three-phase bone scan. This study showed that (99m)Tc-sulesomab had good diagnostic value for the detection of prosthesis infection. The combination of (99m)Tc-sulesomab with other laboratory or imaging examinations may improve diagnostic performance in prosthesis infection and should be investigated further.     

A Case Series of Dacryoendoscopy in Childhood: A Diagnostic and Therapeutic Alternative for Complex Congenital Nasolacrimal Duct Obstruction Even in the First Year of Life

Introduction

Congenital nasolacrimal duct obstruction (CNLDO) is the most common cause of epiphora in infancy. Spontaneous resolution occurs in the majority of the cases by 1 year of age. Nevertheless, obstruction has a negative impact on the outcome of conservative or surgical therapy, especially in cases of complex CNLDO. When the condition persists beyond several months, early intervention with dacryoendoscopy (DE) around the age of 1 year could yield good results. The objective of the study is to analyze the success rate and effectiveness of early DE for complex CNLDO in the first year of life.

Methods

A retrospective, non-comparative case series is presented. DE was performed under general anesthesia in patients between the age of 1 and 12 months with severe recurrent acute or chronic dacryocystitis. The medical histories, intraoperative and postoperative results after 3 months as well as via parents’ interviews were analyzed to investigate the success rate.

Results

A total of 18 consecutive DE in 16 patients between the age of 1 and 12 months (mean 7.3 ± 3.4 months) were studied. Nine lacrimal ducts were diagnosed with persistent chronic dacryocystitis refractory to probing/syringing. The remaining 9 presented recurrent acute dacryocystitis. Diagnostic DE was performed in 18 cases. A therapeutic DE was conducted in 15 lacrimal ducts (83.3%) with simultaneous correction of the associated stenosiswith the tip of the endoscope. A visual controlled opening of the stenosis was impossible in 3 cases due to a too narrow presaccal anatomy (n = 1), an osseous duct stenosis (n = 1), and a bulging membrane of Hasner into the inferior nasal meatus (n = 1). Postoperative findings were classified into four categories: poor, fair, good and excellent. Good results were documented in 16.7% (n = 3) and excellent results in 77.7% (n = 14). The bony obstruction was treated with dacryocystorhinostomy. A minimum follow-up of 3 months was considered for final clinical analysis. Ten patients’ parents (12 surgeries) were interviewed by telephone (mean follow-up 24.8 months). No recurrence of stenosis and no further postoperative complications were observed.

Conclusion

DE is a diagnostic and therapeutic option for complex CNLDO in patients before the age of 1 year. The outcome of DE in the 3 months follow-up is highly indicative of positive final results in terms of patency of the lacrimal duct.

     

Endothelin-B receptors and ventricular arrhythmogenesis in the rat model of acute myocardial infarction

The arrhythmogenic effects of endothelin-1 (ET-1) are mediated via ETA-receptors, but the role of ETB-receptors is unclear. We examined the pathophysiologic role of ETB-receptors on ventricular tachyarrhythmias (VT/VF) during myocardial infarction (MI). MI was induced by coronary ligation in two animal groups, namely in wild-type (n = 63) and in ETB-receptor-deficient (n = 61) rats. Using a telemetry recorder, VT/VF episodes were evaluated during phase I (the 1st hour) and phase II (2–24 h) post-MI, with and without prior β-blockade. Action potential duration at 90% repolarization (APD90) was measured from monophasic epicardial recordings and indices of sympathetic activation were assessed using fast-Fourier analysis of heart rate variability. Serum epinephrine and norepinephrine were measured with radioimmunoassay. MI size was similar in the two groups. There was a marked temporal variation in VT/VF duration; during phase I, it was higher (p = 0.0087) in ETB-deficient (1,519 ± 421 s) than in wild-type (190 ± 34 s) rats, but tended (p = 0.086) to be lower in ETB-deficient (4.2 ± 2.0 s) than in wild-type (27.7 ± 8.0 s) rats during phase II. Overall, the severity of VT/VF was greater in ETB-deficient rats, evidenced by higher (p = 0.0058) mortality (72.0% vs. 32.1%). There was a temporal variation in heart rate and in the ratio of low- to high-frequency spectra, being higher (<0.001) during phase I, but lower (p < 0.05) during phase II in ETB-deficient rats. Likewise, 1 h post-MI, serum epinephrine (p = 0.025) and norepinephrine (p < 0.0001) were higher in ETB-deficient (4.20 ± 0.54, 14.24 ± 1.39 ng/ml) than in wild-type (2.30 ± 0.59, 5.26 ± 0.67 ng/ml) rats, respectively. After β-blockade, VT/VF episodes and mortality were similar in the two groups. The ETB-receptor decreases sympathetic activation and arrhythmogenesis during the early phase of MI, but these effects diminish during evolving MI.     

Authentication and Self-Correction in Sequential MRI Slices

One of the new challenges of Information Technology in the medical world is the protection and authentication of a variety of digital medical files, datasets, and images. In this work, the ability of magnetic resonance imaging (MRI) slice sequences to hide digital data is investigated and more specifically the case that the hidden data are the regions of interest (ROI) of the MRI slices. The regions of non-interest (RONI) are used as cover. The hiding capacity of the whole sequence is taken into account. Any ROI-targeted tampering attempt can be detected, and the original image can be self-restored (under certain conditions) by extracting the ROI from the RONI.     

Prevalence and axial length of hiatus hernia in patients, with nonerosive reflux disease: a prospective study

BACKGROUND AND AIMS: The relationship between hiatus hernia and reflux esophagitis is well established. However, there are conflicting reports regarding its effect on the development of nonerosive reflux disease (NERD). Our aim was to investigate the prevalence and axial length of hiatus hernia in patients with NERD, compared with patients with reflux esophagitis, Barrett esophagus, and controls. METHODS: Axial hernia length of the diaphragmatic hiatus was measured prospectively at endoscopy in controls and patients with typical reflux symptoms occurring at least weekly during the last month relieved by antacids. RESULTS: A final diagnosis of hiatus hernia was established in 21.2% of 249 controls, 60.4% of 346 patients with NERD, 78.1% of 251 patients with reflux esophagitis, and 88.2% of 17 patients with Barrett esophagus. Patients aged >59 years were most likely to have a hiatus hernia. There was an increased prevalence in patients with NERD as compared with controls (P<0.0001), and decreased prevalence as compared with those with reflux esophagitis and Barrett esophagus (P<0.0001 and 0.02, respectively). Axial length of hiatus hernia >3 cm was found more frequently in patients with reflux esophagitis and Barrett esophagus as compared with patients with NERD (P<0.0001 and 0.0052, respectively). There was no statistical significant difference between controls and patients with NERD regarding the prevalence of hiatus hernia >3 cm (P=0.0904). CONCLUSIONS: A small (<3 cm) hiatus hernia may contribute to the development of NERD, whereas an axial length >3 cm is associated with a more severe disease.