Twinkle artifact in renal ultrasound, is it a solid point for the diagnosis of
            renal stone in children?

Background: Twinkle artifact, also known as color Doppler comet-tail artifact, occurs behind very strong, granular, and irregular reflecting interfaces such as crystals, stones, or calcification. This is visualized as a random mixture of red and blue pixels in the high-frequency shift spectrum located deep to the interface. Study results have suggested that the sonographic twinkling artifact may aid in the detection of renal stones with a variety of reference standard imaging modalities, including abdominal radiography, excretory urography, gray-scale sonography, and CT. Material and methods: Our retrospective observational study included children who had undergone abdomen/renal ultrasound for kidneys stones in our radiology department between 2013 and 2019. Presence of the twinkle artifact, and stone numbers and sizes were documented. CT examinations done <3 months prior to or after US were retrospectively assessed to confirm the presence of kidney stones as a reference standard. Results: Thirty-three abdominal renal US scans of 33 patients (21 males, 12 females) fulfilled the entry criteria. The interval between the US and CT was <3 months for all patients. The median overall age of the patients was 4 years (IQR: 3.125, range: 1– 165 months), The median number of days between the US and CT was 13 (IQR: 26, range: 0–81 days). US detected 33 hyperechoic foci suspected to be stones; 26 were confirmed as true positive (i.e. showed the twinkle artifact and were seen in CT), 4 were false positive (showed the twinkle artifact but were not seen in CT), and 3 were false negative (did not show the twinkle artifact but were seen in CT). The overall median stone size was 2 mm in the right kidney, and 5 mm in the left kidney (IQR: 6,11 mm), respectively. Twinkle artifact sensitivity was found to be 89.7% (95% CI 39.574%–90%). The twinkle artifact was assessed in all true-positive stones, determining a relatively high PPV of 26/29 (86.7%) for the twinkle artifact. The twinkle artifact was not dependent on stone size. Specificity for the twinkle artifact could not be calculated due to a lack of true negatives. Conclusion: The twinkle artifact is a sensitive US tool for detecting pediatric kidney and ureter stones, but with a small risk of false positive findings.

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Prediction of Adnexal Torsion by Ultrasound in Women with Acute Abdominal Pain

Ultraschall in der Medizin - European Journal of Ultrasound ◽

10.1055/a-1014-2593 ◽

2019 ◽

Vol 41 (06) ◽

pp. 688-694

Author(s):

Ron Bardin ◽

Noga Perl ◽

Reuven Mashiach ◽

Eitan Ram ◽

Sharon Orbach-Zinger ◽

...

Keyword(s):

Abdominal Pain ◽

Positive Predictive Value ◽

Predictive Value ◽

False Positive ◽

Acute Abdominal Pain ◽

Cohort Analysis ◽

False Negative ◽

True Positive ◽

Adnexal Torsion ◽

Positive Group

Abstract Purpose To investigate the accuracy of ultrasound in the diagnosis of adnexal torsion. Materials and Methods Retrospective cohort analysis of 322 women, presenting to a tertiary medical center with acute abdominal pain, who underwent gynecological examination, sonographic evaluation and laparoscopic surgery, between 2010 and 2016. Findings for adnexal torsion were compared among three groups: positive sonographic findings consistent with surgically confirmed adnexal torsion (true positive, n = 228); negative sonographic findings inconsistent with surgically confirmed adnexal torsion (false negative, n = 42); and positive sonographic findings inconsistent with a surgical diagnosis other than adnexal torsion (false positive, n = 52). Outcome measures were sensitivity and positive predictive value of ultrasound, and its specific features, for the diagnosis of adnexal torsion. Results The sensitivity of ultrasound for adnexal torsion diagnosis was 84.4 %, and the positive predictive value was 81.4 %. Edematous ovary and/or tube, as well as positive whirlpool sign had the highest sensitivity and positive predictive value. The false-negative group had the highest frequency of ovarian cysts (p = 0.0086) and the lowest frequency of ovarian edema (p < 0.0001). The false-positive group had the lowest proportion of pregnant women (p = 0.0022). Significantly more women in the true-positive group had a prior event of adnexal torsion (p = 0.026). Conclusion Ultrasound examination is highly accurate in the diagnosis of adnexal torsion. Clinicians should be aware of the presence of demographic and clinical characteristics that may positively or negatively affect sonographic diagnostic accuracy.

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False-positive diagnosis of breast cancer by diffused optical tomography with ultrasound

Journal of Clinical Oncology ◽

10.1200/jco.2009.27.15_suppl.e22085 ◽

2009 ◽

Vol 27 (15_suppl) ◽

pp. e22085-e22085

Author(s):

X. Wang ◽

Y. Li ◽

X. Cao

Keyword(s):

Breast Cancer ◽

Early Diagnosis ◽

Diagnostic Tool ◽

False Positive ◽

Breast Tumor ◽

Optical Tomography ◽

False Negative ◽

False Negative Rate ◽

Breast Disease ◽

Study Results

e22085 Background: Breast cancer is one of the most common cancer in women. Early detection, early diagnosis and early treatment play key role in fighting against breast cancer. OPTIMUS system is a system of diffused optical tomography with ultrasound. It provides dual modality images for early diagnosis of breast cancer. The aim of this study was to evaluate the OPTIMUS system on diagnosis of breast disease. Methods: OPTIMUS system was applied to 160 breast tumor patients. All patients had received surgical treatment and had definite pathological diagnosis. OPTIMUS system was evaluated as diagnostic tool of breast tumor in this study. Results: There were 42 cases diagnosed as benign breast disease and 118 cases diagnosed as breast cancer by OPTIMUS system. Pathology confirmed 60 cases of benign disease and 100 cases of breast cancer. False positive rate of breast cancer was 30% (18/60). False negative rate of breast cancer was 0% (0/100). The pathology of false positive cases was mild and severe papillomatosis (6/18), non-typical hyperplasia (4/18), chronic inflammation (3/18), fibroadenoma (3/18) and fat necrosis (2/18). Papillomatosis and non-typical hyperplasia are precancerous lesions and often difficult for clinical diagnosis. In this study the false positive diagnostic rate of mammography and ultrasonography is 13% and 11.1% respectively. Conclusions: OPTIMUS system is a non- invasive and highly effective diagnostic tool for breast disease. Its sensitivity is reached to 100% and specificity is about 70% on the diagnosis of breast cancer. OPTIMUS system could be used as assistant diagnostic tool for breast tumor. No significant financial relationships to disclose.

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Parotid Tumors: Fine-Needle Aspiration and/or Frozen Section

Otolaryngology ◽

10.1016/j.otohns.2008.05.139 ◽

2008 ◽

Vol 139 (2_suppl) ◽

pp. P42-P43

Author(s):

Peter Zbaren ◽

Heinz Loosli ◽

Edouard Stauffer

Keyword(s):

Sensitivity And Specificity ◽

Fine Needle Aspiration ◽

False Positive ◽

Frozen Section ◽

False Negative ◽

Needle Aspiration ◽

True Positive ◽

True Negative ◽

Fine Needle ◽

Parotid Neoplasms

Objective Assess the difficulties of preoperative and intraoperative tumor typing of parotid neoplasms. Know the advantages and pitfalls of fine-needle-aspiration cytology (FNAC) and frozen section (FS) analysis in primary parotid neoplasms. Methods In 113 parotid neoplasms (70 malignancies and 43 benign tumors) preoperative FNAC as well as intraoperative FS analysis were performed. FNAC and FS findings were analyzed and compared with the final histopathologic diagnosis. Results The FNAC smear was non-diagnostic in 6 tumors. In 2 FS specimens, it was not possible to determine the tumor dignity. FNAC findings and FS findings were both available in 105 neoplasMS The FNAC findings were true positive for malignancy in 54, true negative in 36, false positive in 4, and false negative in 11 tumors. The accuracy, sensitivity, and specificity were 86%, 83%, and 90% respectively. The FS findings were true positive in 60, true negative in 38, false positive in 2, and false negative in 5 tumors. The accuracy, sensitivity, and specificity were 93%, 92% and 95% respectively. The exact histologic tumor typing by FNAC was correct, false or not mentioned in 58%, 20% and 22% true positive or true negative evaluated tumors, and by FS in 83%, 5% and 12% true positive or true negative evaluated tumors. Conclusions The current analysis showed a superiority of FS compared with FNAC regarding the diagnosis of malignancy and especially of tumor typing. FNAC alone is not prone in many cases to determine the surgical management of primary parotid carcinomas.

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SPK Penentuan Lokasi ATM Menggunakan Metode AHP dan SAW

Jurnal Teknologi dan Sistem Informasi ◽

10.25077/teknosi.v5i1.2019.49-56 ◽

2019 ◽

Vol 5 (1) ◽

pp. 49-56

Author(s):

Gede Surya Mahendra ◽

Kadek Yota Ernanda Aryanto

Keyword(s):

False Positive ◽

Confusion Matrix ◽

False Negative ◽

True Positive ◽

True Negative

Persaingan industri perbankan saat ini semakin meningkat, baik dalam hal penyediaan inovasi produk serta peningkatan kualitas transaksi dan pelayanan. Untuk mengatasi masalah tersebut diciptakan sebuah terminal yang dikenal dengan ATM. Namun fungsionalitas dan efektifitas ATM tersebut belum memenuhi kebutuhan nasabah dikarenakan pengambilan keputusan penentuan lokasi ATM belum menggunakan SPK sehingga banyak kriteria yang terlupakan dalam penentuan lokasi ATM terbaik. Metode AHP yang merupakan sebuah hierarki fungsional dengan input utamanya adalah persepsi manusia sedangkan metode SAW dengan konsep dasar mencari penjumlahan terbobot dari rating kinerja pada setiap alternatif pada semua atribut. AHP digunakan untuk memberikan pembobotan pada masing-masing kriteria dan SAW untuk melakukan perangkingan dari masing-masing alternatif. Terdapat 7 kriteria dengan 11 sub kriteria pada pembobotan dan 76 data alternatif. Pengujian dilakukan dengan membandingkan hasil delpoyment ATM dengan hasil perhitungan sistem. Dari 76 data alternatif yang diujikan, terdapat 38 lokasi deployment ATM. Dari hasil pengujian yang ditampilkan dalam confusion matrix, pada kriteria yang tidak teruji signifikansi didapatkan 33 data True Positive, 38 True Negative, 5 False Negative dan 5 False Positive dengan akurasi sebesar 86,84%, dan pada kriteria yang teruji signifikansi didapatkan 35 data True Positive, 35 True Negative, 3 False Negative dan 3 False Positive memiliki akurasi 92,11%.

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Otkrivanje infekcija u abdomenu primenom radioobelezenog antibiotika

Acta chirurgica iugoslavica ◽

10.2298/aci0302025a ◽

2003 ◽

Vol 50 (2) ◽

pp. 25-29 ◽

Cited By ~ 1

Author(s):

Vera Artiko ◽

Branka Davidovic ◽

Nadezda Nikolic ◽

Milorad Petrovic ◽

Nebojsa Petrovic ◽

...

Keyword(s):

Differential Diagnosis ◽

Surgical Treatment ◽

False Positive ◽

Bacterial Infections ◽

Conservative Therapy ◽

False Negative ◽

True Positive ◽

True Negative ◽

Exact Localization

The aim of the study is detection of the abdominal infective foci using 99mTc-ciprofloxacin, radiopharmaceutical supposed to distuinguish inflammation from infection. Twenty one patient was investigated. There were 11 true positive findings, 7 true negative, two were false negative, while 1 was false positive. Sensitivity of the method was 79% and specificity 91%. According to our results, scintigraphy with infecton is a useful method for detection and assessment of exact localization of deep seated bacterial infections, which might be useful for (differential) diagnosis, surgical treatment in due time as well as monitoring of the treatment of conservative therapy.

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Preferred screening test for Cushing’s syndrome screening

Endocrinology and Disorders ◽

10.31579/2640-1045/053 ◽

2020 ◽

Vol 4 (1) ◽

pp. 01-05

Author(s):

Ahmed Siddiqi

Keyword(s):

False Positive ◽

Screening Test ◽

False Negative ◽

True Positive ◽

True Negative ◽

Inhaled Steroids ◽

Free Cortisol ◽

Suppression Test ◽

Dexamethasone Suppression ◽

Hospital General

Background: In our practice 24 hours urine collection for free cortisol (24Hr UFC) and overnight dexamethasone suppression test (ONDST) are initial investigations to screen patients for hyper-cortisolism. I audited our practice to find our clinicians’ and patients’ choice of first screening investigation for hyper-cortisolism. Method & material: Electronic and paper medical records of patients who underwent 24Hr UFC and/or ONDST at our hospital over previous consecutive twenty four months were examined. 62 such patients were identified but 12 patients were excluded from analysis. We tried to contact 30 patients over consecutive 48 hours over the phone who underwent both 24Hr UFC and ONDST. We managed to contact 18 patients and asked them two study questions. Data & results: 33 (66%) patients were female and 17 (33%) were male. 20 (40%) had 24Hr UFC alone and 30 (60%) patients had both. In total 80 such investigations completed 30 being ONDST and 50 24hr UFC. 53 (66%) of the investigations were requested by Endocrinologists, 21 (26%) by Hospital General Physicians and 6 (8%) by General practitioners (GP). For UFC 10 (20%) were true positive, 31 (62%) were false positive, 6 (12%) were true negative and 0% false negative. 3 (6%) 24Hr UFC samples were not collected properly and were not processed for results. Out of the total false positives (31 patients), 6 (19.3%) cases were of alcohol excess, 4 (13%) of dépression, 3 (9.7%) of inhaled steroids and 1 (3.2%) of sleep apnea. For the ONDST 7 (23.3%) true positive, 4 (13.3%) false positive 19 (63.4%) true negative and 0% false negative. All 18 patients contacted over the phone answered both questions. 16 preferred ONDST over 24Hr UFC, 1 patient had no preference and 1 patient preferred 24Hr UFC over ONDST. Conclusion: Patients overwhelmingly preferred ONDST as first screening test in contrast to physician’s choice of 24Hr UFC.

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Efficacy of Transcranial Motor Evoked Potential Monitoring During Intra- and Extramedullary Spinal Cord Tumor Surgery: A Prospective Multicenter Study of the Monitoring Committee of the Japanese Society for Spine Surgery and Related Research

Global Spine Journal ◽

10.1177/21925682211011443 ◽

2021 ◽

pp. 219256822110114

Author(s):

Hiroki Ushirozako ◽

Go Yoshida ◽

Shiro Imagama ◽

Kazuyoshi Kobayashi ◽

Kei Ando ◽

...

Keyword(s):

Spinal Cord ◽

False Positive ◽

Evoked Potential ◽

Spinal Cord Tumor ◽

False Negative ◽

Motor Evoked Potential ◽

True Positive ◽

True Negative ◽

Intramedullary Spinal Cord ◽

Transcranial Motor Evoked Potential

Study Design: Multicenter prospective study. Objectives: Although intramedullary spinal cord tumor (IMSCT) and extramedullary SCT (EMSCT) surgeries carry high risk of intraoperative motor deficits (MDs), the benefits of transcranial motor evoked potential (TcMEP) monitoring are well-accepted; however, comparisons have not yet been conducted. This study aimed to clarify the efficacy of TcMEP monitoring during IMSCT and EMSCT resection surgeries. Methods: We prospectively reviewed TcMEP monitoring data of 81 consecutive IMSCT and 347 EMSCT patients. We compared the efficacy of interventions based on TcMEP alerts in the IMSCT and EMSCT groups. We defined our alert point as a TcMEP amplitude reduction of ≥70% from baseline. Results: In the IMSCT group, TcMEP monitoring revealed 20 true-positive (25%), 8 rescue (10%; rescue rate 29%), 10 false-positive, a false-negative, and 41 true-negative patients, resulting in a sensitivity of 95% and a specificity of 80%. In the EMSCT group, TcMEP monitoring revealed 20 true-positive (6%), 24 rescue (7%; rescue rate 55%), 29 false-positive, 2 false-negative, and 263 true-negative patients, resulting in a sensitivity of 91% and specificity of 90%. The most common TcMEP alert timing was during tumor resection (96% vs. 91%), and suspension surgeries with or without intravenous steroid administration were performed as intervention techniques. Conclusions: Postoperative MD rates in IMSCT and EMSCT surgeries using TcMEP monitoring were 25% and 6%, and rescue rates were 29% and 55%. We believe that the usage of TcMEP monitoring and appropriate intervention techniques during SCT surgeries might have predicted and prevented the occurrence of intraoperative MDs.

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Diagnostic Value of MRI for Detecting Recurrent Soft-Tissue Sarcoma in a Long-Term Analysis at a Multidisciplinary Sarcoma Center

10.21203/rs.3.rs-111370/v1 ◽

2020 ◽

Author(s):

Sam Sedaghat ◽

Maya Sedaghat ◽

Jens Meschede ◽

Olav Jansen ◽

Marcus Both

Keyword(s):

Radiation Therapy ◽

Soft Tissue ◽

Diagnostic Accuracy ◽

False Positive ◽

False Negative ◽

True Positive ◽

Primary Tumors ◽

Negative Results

Abstract Background: To assess the long-term diagnostic accuracy of MRI for detecting recurrent soft-tissue sarcoma at a multidisciplinary sarcoma center.Methods: In all, 1055 postoperative follow-up MRIs of 204 patients were included in the study. MRI follow-up scans were systematically reviewed for true-positive/-negative and false-positive/-negative results in detecting recurrent tumor. Available pathological reports and follow-up MRIs were set as reference. Results: The median age of the patients was 55.3±18.2 years. Of the patients, 34.8% presented with recurrences. Here, 65 follow-up scans were true positive, 23 false positive, 6 false negative, and 961 true negative. The overall sensitivity and specificity of MRI for detecting recurrences were 92% and 98%, respectively, with an accuracy of 97%. For intramuscular lesions and after surgery alone the sensitivity was higher (95% and 97%) than for subcutaneous lesions and surgery with additional radiation therapy (83% and 86%, respectively), at similarly high specificities (96-98%). The 6 false-negative results were found in streaky (n=2) and small ovoid/nodular (n=4) recurring lesions. The false-positive lesions imitated streaky (n=14), ovoid/nodular (n=8), and polycyclic/multilobulated recurring tumors (n=1). All false-positive results were found in patients in whom the primary tumors were polycyclic/multilobulated in appearance.Conclusion: MRI shows a high diagnostic accuracy for detecting recurrent STS, with a high sensitivity and specificity. The diagnostic accuracy decreases in subcutaneous lesions and after surgery with radiation therapy, compared to intramuscular lesions and surgery alone. Radiologists should pay particular attention to streaky and small ovoid/nodular recurring lesions and patients with polycyclic/multilobulated primary tumors.

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Assessment of Health Monitoring Trustworthiness of Avionics Systems

International Journal of Prognostics and Health Management ◽

10.36001/ijphm.2021.v12i2.2907 ◽

2021 ◽

Vol 12 (2) ◽

Author(s):

Vladimir Ulansky ◽

Igor Machalin ◽

Iryna Terentyeva

Keyword(s):

Health Monitoring ◽

False Positive ◽

False Negative ◽

Measuring Channel ◽

True Positive ◽

Very High Frequency ◽

True Negative ◽

Automated Test Equipment ◽

Intermittent Faults ◽

Reliability Characteristics

The article provides a methodology for assessing the trustworthiness of health monitoring the dismounted avionics systems with automated test equipment (ATE). The indicators include the probabilities of false-positive, false-negative, true-positive, and true-negative. For the first time, we introduced into consideration the instability of the source of stimulus signal (SSS), the random and systematic component of the measuring channel error, and the reliability characteristics of the systems themselves. We consider a specific case of an exponential distribution of permanent failures and intermittent faults and derive formulas for calculating the trustworthiness indicators. Numerical calculations illustrate how the probabilities of correct and incorrect decisions depend on accuracy parameters. We show that the probabilities of false-positive and false-negative increase much faster than the probabilities of true-positive and true-negative decrease when the standard deviation of stimulus signal increases. For a Very High-Frequency Omni-Directional Range (VOR) receiver, we demonstrate that even with a zero random error generated by the source of the stimulus signal, the probabilities of false-positive and false-negative are different from zero.

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Clinical significance of prenatal diagnosis of macrosomia by ultrasound

Journal of obstetrics and women s diseases ◽

10.17816/jowd63312-20 ◽

2014 ◽

Vol 63 (3) ◽

pp. 12-20

Author(s):

Irina Yuryevna Bayeva

Keyword(s):

Birth Weight ◽

Prenatal Diagnosis ◽

False Positive ◽

False Negative ◽

Fetal Weight ◽

True Positive ◽

Perinatal Complications ◽

True Negative ◽

Average Accuracy ◽

Study Population

Оbjective: Establish the diagnostic value of ultrasound examination in prenatal diagnosis of macrosomia among the women without diabetes and to determine its effect on birth outcomes. Мethods: This is a retrospective cohort study done at the Orenburg municipal perinatal center and maternity hospital № 2 since 2006 to 2012. In this study 3760 pregnant women were analyzed who delivered term, singleton, live born infants. The estimated fetal sonographic weight by the formula Hadlock’s was obtained within the last week prior to delivery. The study population was divided into 4 groups (true positive, true negative, false positive, false negative) according to the estimated fetal weight (EFW) and regarding the birth weight (BW). Receiver-operating characteristics (ROC) curves were generated to compare the prediction of macrosomia when using different observation methods. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy were calculated. The mean value of two groups were compared using two sample t test and χ² test for comparison of proportions. Results: In order to assess the accuracy of the ultrasound in prenatal diagnosis of macrosomia the study population was divided into 4 groups according to the estimated fetal weight (EFW) and regarding the birth weight (BW): true positive (n-147), false negative (n-229 ), false positive (n-353), true negative (n-3031). Results of the study showed no statistically significant differences between the birth weight and estimated fetal weifht by ultrasound alone only in the macrosomia group with true-positive results (p = 0.9). In applying the ROC (Receiver Operating Characteristic curve) performance analysis sensitivity and spesificity in the prediction of the macrosomia by ultrasound revealed the average predictive power of the method. Area under the curve (Area under ROC curve, AUC) made 0.7295 (95 % CI: 0.695-0.781), which corresponds to a predetermined average accuracy. The accuracy of macrosomia prediction by ultrasound methods was 90 %, sensitivity - 35 %, specificity - 93,5 %. Сesarian sections were performed for 40 % of the pregnant women, where fetal macrosomia was truly ruled in (true positive) and 16% of the women who delivered normal weight infants (true negative). Overestimation of fetal weight (false positive) has led to the 30 % rate of cesarean sections. Underestimation of fetal weight (false negative) has decreased to the 24% rate of cesarean sections but in this case perinatal complications have increased. Conclusion: Results showed an average accuracy in predicting macrosomia by the formula Hadlock’s. The results of the study have proved that the inappropriate prediction macrosomia of fetal weight has influence on the mode of delivery. Overestimation of fetal weight has led the proportion of cesarian sections. Underestimation of fetal macrosomia has increased perinatal complications.

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