scholarly journals Lorenz Plot Analysis in Dogs with Sinus Rhythm and Tachyarrhythmias

Animals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1645
Author(s):  
Giovanni Romito ◽  
Carlo Guglielmini ◽  
Helen Poser ◽  
Marco Baron Toaldo

The Lorenz plot (LP), a graphical representation of heart rate variability, has been poorly studied in dogs to date. The present study aimed to describe the graphic features of LP in dogs with sinus rhythm (SR) and tachyarrhythmias, and to analyze the usefulness of its pattern recognition. One hundred and nineteen canine Holter recordings were retrospectively evaluated. Cardiac rhythms were classified as: SR; SR with frequent (>100) premature ectopies (atrial, SR-APCs; ventricular, SR-VPCs; atrial and ventricular, SR-APCs-VPCs); atrial fibrillation (AF); and AF with frequent VPCs (AF-VPCs). Lorenz plots were studied qualitatively and quantitatively, and classified by distinct LP patterns (LPPs). Repeatability and reproducibility of LPP classification and diagnostic value were determined. Recordings included: 48 SR, 9 SR-APCs, 35 SR-VPCs, 5 SR-APCs-VPCs, 4 AF, and 18 AF-VPCs. Ten LPPs were identified: comet (n = 12), torpedo (n = 3), Y-shaped (n = 6), diamond (n = 10), diamond with a central silent zone (n = 17), double side-lobe (DSL) (n = 47), triple side-lobe (n = 1), quadruple side-lobe (n = 2), fan (n = 18), and fan with DSL (n = 3). Repeatability and reproducibility of LPP classification were excellent. The DSL pattern was both highly sensitive (91.3%) and specific (94.5%) for SR with frequent premature ectopies, either APCs, or VPCs, or both. The remaining LPPs had lower diagnostic value (high specificity but low sensitivity). Distinct rhythms imprint distinct and reproducible LPPs in dogs. The majority of canine LPPs are specific but insensitive indicators of SR and tachyarrhythmias.

2016 ◽  
Vol 10 (1) ◽  
pp. 457-465 ◽  
Author(s):  
Friedrich Boettner ◽  
Gabriele Koehler ◽  
Alexander Wegner ◽  
Tom Schmidt-Braekling ◽  
Georg Gosheger ◽  
...  

Objective: The current study investigates the diagnostic accuracy of the criteria described for frozen sections and whether modern leukocyte specific staining techniques including leukocyte peroxidase and Naphtol-AS-D-chloroacetate-esterase will improve the accuracy of the intra-operative histology. Method: 77 patients undergoing revision total hip and knee arthroplasty were included in this retrospective study. Patients were grouped into septic and aseptic based on intraoperative cultures. Tissue samples were analyzed utilizing the Mirra, Feldman, Lonner, Banit and Athanasou criteria. Results: An experienced pathologist had a high specificity (96%), but rather low sensitivity (57%) diagnosing infection. By using the Banit-, Mirra-, or Athanasou-criteria the sensitivity is increased to 0.90. The Feldman- and Lonner-criteria have a lower sensitivity (0.48 and 0.38), however, an increased specificity of 0.96 and 0.98, respectively. The Banit cut off has the highest accuracy (86%). MPOX and NACE staining increased the sensitivity and accuracy up to 100% and 92% respectively. Conclusion: Banit’s cut off is the most accurate histologic criteria to diagnose infection. Modern leukocyte specific staining techniques slightly improve the accuracy. The synovial fluid white blood cell count appears to be the most accurate intraoperative test.


Author(s):  
Congliang Miao ◽  
Mengdi Jin ◽  
Li Miao ◽  
Xinying Yang ◽  
Peng Huang ◽  
...  

AbstractObjectiveThe purpose of this study is to distinguish the imaging features of COVID-19 with other chest infectious diseases and evaluate diagnostic value of chest CT for suspected patients.MethodsAdult suspected patients aged>18 years within 14 days who underwent chest CT scan and reverse-transcription polymerase-chain-reaction (RT-PCR) tests were enrolled. The enrolled patients were confirmed and grouped according to results of RT-PCR tests. The data of basic demographics, single chest CT features, and combined chest CT features were analyzed for confirmed and non-confirmed groups.ResultsA total of 130 patients were enrolled with 54 cases positive and 76 cases negative. The typical CT imaging features of positive group were ground glass opacity (GGO), crazy-paving pattern and air bronchogram. The lesions were mostly distributed bilaterally, close to the lower lungs or the pleura. When features combined, GGO with bilateral pulmonary distribution and GGO with pleural distribution were more common, of which were 31 cases (57.4%) and 30 cases (55.6%) respectively. The combinations were almost presented statistically significant (P<0.05) except for the combination of GGO with consolidation. Most combinations presented relatively low sensitivity but extremely high specificity. The average specificity of these combinations is around 90%.ConclusionsThe combinations of GGO could be useful in the identification and differential diagnosis of COVID-19, which alerts clinicians to isolate patients for treatment promptly and repeat RT-PCR tests until incubation ends.


2021 ◽  
pp. 24-24
Author(s):  
Bojana Dacic-Krnjaja ◽  
Milan Hadzi-Milic ◽  
Jelena Potic ◽  
Danijela Raonic ◽  
Milenko Stojkovic

Introduction/Objective. The objective of this paper was to assess the diagnostic value of three simple dry eye (DE) tests: lid parallel conjunctival folds (LIPCOF), tear meniscus height (TMH), and tear ferning (TF). Methods. Diagnostic DE tests LIPCOF, TMH and TF tests were performed in 100 patients. Eighty of them were referred to us by rheumatologists and general practitioners either during evaluation for Sj?gren?s syndrome, or because of DE symptoms. Control group was made of 20 patients, with no DE relating symptoms. Ocular Surface Disease Index (OSDI) questionnaire was used for DE symptoms? evaluation. Results of LIPCOF, TMH and TF tests were compared with results of Copenhagen criteria (CC) DE tests i.e., tear fluorescein break up time, Schirmer I and Rose Bengal tests. Ability of tests to recognize DE in various grades according to Dry Eye Work Shop (DEWS) report score system was assessed. Results. Compared to CC, sensitivity of LIPCOF and TMH was high: 92.8% and 83.5%, while specificity was low: 34.4% and 49.2%, respectively. TF had low sensitivity of 59.1% but high specificity of 82.7%. Mean values of both LIPCOF and TMH differed significantly (F = 7.222, p < 0.001 and F = 11.802, p < 0.001) between control group and all DEWS DE grades, but not among different grades of DE. Conclusions. Diagnostic tests TMH and LIPCOF showed high sensitivity which makes them excellent screening DE tests. Low sensitivity of TF suggests that it is not truly a good screening test on its own, but its high specificity is of definite value.


2020 ◽  
Author(s):  
K. De Smet ◽  
D. De Smet ◽  
I. Demedts ◽  
B. Bouckaert ◽  
T. Ryckaert ◽  
...  

Structured abstractBackgroundchest CT is increasingly used for COVID-19 screening in healthcare systems with limited SARS-CoV-2 PCR capacity. Its diagnostic value was supported by studies with methodological concerns and its use is controversial. Here we investigated its potential to diagnose COVID-19 in symptomatic patients and to screen asymptomatic patients in a prospective study with minimal selection bias.MethodsFrom March 19, 2020 to April 20, 2020 we performed parallel SARS-CoV-2 PCR and CT with categorization of COVID-19 suspicion by CO-RADS, in 859 patients with COVID-19 symptoms and 1138 controls admitted to the hospital for COVID-19 unrelated medical urgencies. CT-CORADS was categorized on a 5-point scale from 1 (very low suspicion) to 5 (very high suspicion). AUC under ROC curve were calculated in symptomatic versus asymptomatic patients to predict positive SARS-CoV-2 positive PCR and likelihood ratios for each CO-RADS score were used for rational selection of diagnostic thresholds.FindingsCT-CORADS had significant (P<0.0001) diagnostic power in both symptomatic (AUC=0.891) and asymptomatic (AUC=0.700) patients hospitalized during SARS-CoV-2 peak prevalence. In symptomatic patients (41.7% PCR+), CO-RADS ≥ 3 detected positive PCR with high sensitivity (89.1%) and 72.5% specificity. In asymptomatic patients (5.3% PCR+), a CO-RADS score ≥ 3 detected SARS-CoV-2 infection with low sensitivity (45.0%) but high specificity (88.8%).InterpretationCT-CORADS has meaningful diagnostic power in symptomatic patients, supporting its application for time-sensitive triage. Sensitivity in asymptomatic patients is insufficient to justify its use as screening approach. Incidental detection of CO-RADS ≥ 3 in asymptomatic patients should trigger reflex testing for respiratory pathogens.


1996 ◽  
Vol 5 (1) ◽  
pp. 90-96 ◽  
Author(s):  
Frank E. Musiek ◽  
Cynthia A. McCormick ◽  
Raymond M. Hurley

We performed a retrospective study of 26 patients with acoustic tumors and 26 patients with otologically diagnosed cochlear pathology to determine the sensitivity (hit rate), specificity (false-alarm rate), and efficiency of six auditory brainstem response indices. In addition, a utility value was determined for each of these six indices. The I–V interwave interval, the interaural latency difference, and the absolute latency of wave V provided the highest hit rates, the best A’ values and good utility. The V/I amplitude ratio index provided high specificity but low sensitivity scores. In regard to sensitivity and specificity, using the combination of two indices provided little overall improvement over the best one-index measures.


2016 ◽  
Vol 55 (01) ◽  
pp. 15-20 ◽  
Author(s):  
J. Farahati ◽  
A. G. Müller ◽  
E. Gillman ◽  
M. Hentschel ◽  
F. H. H. Müller

SummaryAim: To evaluate the diagnostic value (sensitivity, specificity) of positron emission mammography (PEM) in a single site non-interventional study using the maximum PEM uptake value (PUVmax). Patients, methods: In a singlesite, non-interventional study, 108 patients (107 women, 1 man) with a total of 151 suspected lesions were scanned with a PEM Flex Solo II (Naviscan) at 90 min p.i. with 3.5 MBq 18F-FDG per kg of body weight. In this ROI(region of interest)-based analysis, maximum PEM uptake value (PUV) was determined in lesions, tumours (PUVmaxtumour), benign lesions (PUVmaxnormal breast) and also in healthy tissues on the contralateral side (PUVmaxcontralateral breast). These values were compared and contrasted. In addition, the ratios of PUVmaxtumour / PUVmaxcontralateral breast and PUVmaxnormal breast / PUVmaxcontralateral breast were compared. The image data were interpreted independently by two experienced nuclear medicine physicians and compared with histology in cases of suspected carcinoma. Results: Based on a criteria of PUV>1.9, 31 out of 151 lesions in the patient cohort were found to be malignant (21%). A mean PUVmaxtumour of 3.78 ± 2.47 was identified in malignant tumours, while a mean PUVmaxnormal breast of 1.17 ± 0.37 was reported in the glandular tissue of the healthy breast, with the difference being statistically significant (p < 0.001). Similarly, the mean ratio between tumour and healthy glandular tissue in breast cancer patients (3.15 ± 1.58) was found to be significantly higher than the ratio for benign lesions (1.17 ± 0.41, p < 0.001). Conclusion: PEM is capable of differentiating breast tumours from benign lesions with 100% sensitivity along with a high specificity of 96%, when a threshold of PUVmax >1.9 is applied.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Bei Zhang ◽  
Shuhui Hong ◽  
Guihui Zhang ◽  
Fengnian Rong

Abstract Background Colposcopy offers an accurate way to the diagnose of cervical precancerous lesions. However, the diagnostic accuracy of colposcopy is unsatisfied. This study was to evaluate colposcopic accuracy according to the 2011 International Federation of Cervical Pathology and Colposcopy (IFCPC) terminology. Methods A retrospective cohort study was performed in 1,838 patients who underwent colposcopy in Shandong Qianfoshan Hospital, Cheeloo College of Medicine, Shandong University from October 2013 to April 2018. Using conization or cervical biopsy pathology as the gold standard, the agreement between colposcopic diagnosis and pathologic diagnosis was calculated, and correlations between variables were analyzed. Results As an authoritative and widely used terminology for colposcopy diagnosis, the 2011 IFCPC terminology has certain clinical practicality and diagnostic accuracy. However, some signs such as mosaic, punctation, sharp border, inner border sign and ridge sign had high specificity but unsatisfactory sensitivity, which limited the diagnostic value. Therefore, we discussed the Lugol’s staining, a very common sign in colposcopy, and analyzed the diagnostic significance of bright yellow staining in low-grade squamous intraepithelial lesion (LSIL) and mustard yellow staining in high-grade squamous intraepithelial lesion (HSIL). The results showed that mustard yellow may be a valuable indicator in the diagnosis of HSIL. Conclusion The 2011 IFCPC colposcope terminology has standardized interpretations of the colposcopic findings and improved the accuracy of colposcopy diagnosis. The aceto-white epithelium still has important diagnostic value; however, the value of a few signs is needed to be discussed and new signs are expected to be discovered. Although the significance of Lugol’s staining was diminishing, mustard yellow might be a valuable indicator for the diagnosis of HSIL.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Prashanth Gopalan ◽  
Yunshan Wang ◽  
Berardi Sensale-Rodriguez

AbstractWhile terahertz spectroscopy can provide valuable information regarding the charge transport properties in semiconductors, its application for the characterization of low-conductive two-dimensional layers, i.e., σs <  < 1 mS, remains elusive. This is primarily due to the low sensitivity of direct transmission measurements to such small sheet conductivity levels. In this work, we discuss harnessing the extraordinary optical transmission through gratings consisting of metallic stripes to characterize such low-conductive two-dimensional layers. We analyze the geometric tradeoffs in these structures and provide physical insights, ultimately leading to general design guidelines for experiments enabling non-contact, non-destructive, highly sensitive characterization of such layers.


Nanomaterials ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1207
Author(s):  
Hong Jae Cheon ◽  
Quynh Huong Nguyen ◽  
Moon Il Kim

Inspired by the active site structure of natural horseradish peroxidase having iron as a pivotal element with coordinated histidine residues, we have developed histidine coated magnetic nanoparticles (His@MNPs) with relatively uniform and small sizes (less than 10 nm) through one-pot heat treatment. In comparison to pristine MNPs and other amino acid coated MNPs, His@MNPs exhibited a considerably enhanced peroxidase-imitating activity, approaching 10-fold higher in catalytic reactions. With the high activity, His@MNPs then were exploited to detect the important neurotransmitter acetylcholine. By coupling choline oxidase and acetylcholine esterase with His@MNPs as peroxidase mimics, target choline and acetylcholine were successfully detected via fluorescent mode with high specificity and sensitivity with the limits of detection down to 200 and 100 nM, respectively. The diagnostic capability of the method is demonstrated by analyzing acetylcholine in human blood serum. This study thus demonstrates the potential of utilizing His@MNPs as peroxidase-mimicking nanozymes for detecting important biological and clinical targets with high sensitivity and reliability.


Author(s):  
Luma Cordeiro Rodrigues ◽  
Silvia Ferrite ◽  
Ana Paula Corona

Abstract Purpose This article investigates the validity of a smartphone-based audiometry for hearing screening to identify hearing loss in workers exposed to noise. Research Design This is a validation study comparing hearing screening with the hearTest to conventional audiometry. The study population included all workers who attended the Brazilian Social Service of Industry to undergo periodic examinations. Sensitivity, specificity, the Youden index, and positive (PPV) and negative predictive values (NPV) for hearing screening obtained by the hearTest were estimated according to three definitions of hearing loss: any threshold greater than 25 dB hearing level (HL), the mean auditory thresholds for 0.5, 1, 2, and 4 kHz greater than 25 dB HL, and the mean thresholds for 3, 4, and 6 kHz greater than 25 dB HL. Note that 95% confidence intervals were calculated for all measurements. Results A total of 232 workers participated in the study. Hearing screening with the hearTest presented good sensitivity (93.8%), specificity (83.9%), and Youden index (77.7%) values, a NPV (97.2%), and a low PPV (69.0%) for the identification of hearing loss defined as any auditory threshold greater than 25 dB HL. For the other definitions of hearing loss, we observed high specificity, PPV and NPV, as well as low sensitivity and Youden index. Conclusion The hearTest is an accurate hearing screening tool to identify hearing loss in workers exposed to noise, including those with noise-induced hearing loss, although it does not replace conventional audiometry.


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