scholarly journals Low frequency interictal EEG biomarker for localizing seizures

2021 ◽  
Author(s):  
Brian Lundstrom ◽  
Benjamin Brinkmann ◽  
Gregory Worrell
Keyword(s):  
Positive Predictive Value ◽  
Surgical Resection ◽  
Patient Outcomes ◽  
Predictive Value ◽  
Low Frequency ◽  
Seizure Onset ◽  
Prognostic Information ◽  
Eeg Activity ◽  
Epileptiform Discharges ◽  
Interictal Eeg

Objective: We want to identify seizure onset zone (SOZ) from interictal EEG biomarkers. We hypothesize that a combination of interictal EEG biomarkers, including a novel low frequency marker, can predict mesial temporal involvement and can assist in prognosis related to surgical resections. Methods: Interictal direct current wide bandwidth invasive EEG recordings from 83 patients implanted with 5,111 electrodes were retrospectively studied. Logistic regression was used to classify electrodes and patient outcomes. A feed-forward neural network was implemented to understand putative mechanisms. Results: Interictal infraslow frequency EEG activity was decreased for SOZ electrodes while faster frequencies such as delta (2-4 Hz) and beta-gamma (20-50 Hz) activity were increased. These spectral changes comprised a novel interictal EEG biomarker that was significantly increased for mesial temporal SOZ electrodes compared to non-SOZ electrodes. Interictal EEG biomarkers correctly classified mesial temporal SOZ electrodes with a specificity of 87% and positive predictive value of 80%. These interictal EEG biomarkers also correctly classified patient outcomes after surgical resection with a specificity of 91% and positive predictive value of 87%. Interpretation: Interictal infraslow EEG activity is decreased near the SOZ while higher frequency power is increased, suggesting distinct underlying physiologic mechanisms. Decreased interictal infraslow activity may reflect the loss of neural inhibition. Narrowband interictal EEG power bands provide information about the SOZ and can help predict mesial temporal involvement in seizure onset. Together with interictal epileptiform discharges and high frequency oscillations, these interictal biomarkers may provide prognostic information prior to surgical resection.

scholarly journals Low frequency novel interictal EEG biomarker for localizing seizures and predicting outcomes

2021 ◽  
Author(s):  
Brian Nils Lundstrom ◽  
Benjamin Brinkmann ◽  
Gregory Worrell
Keyword(s):  
Positive Predictive Value ◽  
Patient Outcomes ◽  
Predictive Value ◽  
Low Frequency ◽  
Seizure Onset ◽  
Eeg Activity ◽  
Seizure Onset Zone ◽  
Interictal Eeg ◽  
Eeg Power ◽  
Frequency Power

Abstract Localizing hyperexcitable brain tissue to treat focal seizures remains challenging. We want to identify the seizure onset zone from interictal EEG biomarkers. We hypothesize that a combination of interictal EEG biomarkers, including a novel low frequency marker, can predict mesial temporal involvement and can assist in prognosis related to surgical resections. Interictal direct current wide bandwidth invasive EEG recordings from 83 patients implanted with 5,111 electrodes were retrospectively studied. Logistic regression was used to classify electrodes and patient outcomes. A feed-forward neural network was implemented to understand putative mechanisms. Interictal infraslow frequency EEG activity was decreased for seizure onset zone electrodes while faster frequencies such as delta (2–4 Hz) and beta-gamma (20–50 Hz) activity were increased. These spectral changes comprised a novel interictal EEG biomarker that was significantly increased for mesial temporal seizure onset zone electrodes compared to non-seizure onset zone electrodes. Interictal EEG biomarkers correctly classified mesial temporal seizure onset zone electrodes with a specificity of 87% and positive predictive value of 80%. These interictal EEG biomarkers also correctly classified patient outcomes after surgical resection with a specificity of 91% and positive predictive value of 87%. Interictal infraslow EEG activity is decreased near the seizure onset zone while higher frequency power is increased, which may suggest distinct underlying physiologic mechanisms. Narrowband interictal EEG power bands provide information about the seizure onset zone and can help predict mesial temporal involvement in seizure onset. Narrowband interictal EEG power bands may be less useful for predictions related to non-mesial temporal electrodes. Together with interictal epileptiform discharges and high frequency oscillations, these interictal biomarkers may provide prognostic information prior to surgical resection. Computational modeling suggests changes in neural adaptation may be related to the observed low frequency power changes.

scholarly journals Guidelines for diagnosis and monitoring of thyroid disease: nonthyroidal illness

1996 ◽  
Vol 42 (1) ◽  
pp. 188-192 ◽  
Author(s):  
J R Stockigt
Keyword(s):  
Positive Predictive Value ◽  
Clinical Features ◽  
Thyroid Function ◽  
Predictive Value ◽  
Thyroid Disease ◽  
Thyroid Dysfunction ◽  
Reference Intervals ◽  
Free T4 ◽  
Prognostic Information ◽  
Increased Risk

Abstract On the basis of low specificity, poor positive predictive value, and cost, there is at present no basis for routine assessment of thyroid function in acutely hospitalized patients, unless clinical features suggest the possibility of thyroid dysfunction, or a patient's background increases the likelihood of thyroid dysfunction. When used in severely ill patients, estimates of both thyroxine (T4) and thyrotropin (TSH) show a high prevalence of abnormal results, but lack specificity and have poor positive predictive value for true thyroid disease. When thyroid function is tested in the critically ill, the positive predictive value for true thyroid disease of both free T4 and TSH measurements could be improved by using wider reference intervals than for unselected populations. The knowledge of nonspecific disease-related abnormalities of triiodothyronine, T4, and TSH is not currently likely to yield useful prognostic information or to alter management for individual patients. Thyroid testing should be readily available for any acutely ill patient with any clinical features that suggest thyroid dysfunction, and for groups at increased risk of thyroid dysfunction. An initial abnormal result for either TSH or free T4 estimate should be followed by combined analysis of free T4 and TSH with the best available methodology. Diagnosis of thyroid dysfunction should be based on the T4-TSH relation rather than either value alone. Persistence of an apparent diagnostic abnormality should be confirmed before therapy is commenced.

scholarly journals Evaluation of the Afirma Gene Expression Classifier in Repeat Indeterminate Thyroid Nodules

2017 ◽  
Vol 141 (7) ◽  
pp. 985-989 ◽  
Author(s):  
Grant Harrison ◽  
Julie Ann Sosa ◽  
Xiaoyin Jiang
Keyword(s):  
Gene Expression ◽  
Positive Predictive Value ◽  
Surgical Resection ◽  
San Francisco ◽  
Predictive Value ◽  
Thyroid Nodules ◽  
Surgical Pathology ◽  
Molecular Testing ◽  
Fine Needle ◽  
Gene Expression Classifier

Context.— Molecular testing in indeterminate thyroid nodules is a rapidly evolving field with variable reported outcomes. Objective.— To report our experience at a tertiary thyroid referral center with the Afirma Gene Expression Classifier (Veracyte, San Francisco, California) in repeat fine-needle aspirations of thyroid nodules with a previous indeterminate cytologic result. Design.— Results of cytopathology and the Afirma test were collected from August 2013 to March 2015, as were diagnoses from surgical resection when performed. Results.— One hundred and fifteen thyroid nodules were evaluated by Afirma. The fine-needle aspiration diagnostic categories for these nodules were 100 (87%) Bethesda III, 10 (9%) Bethesda IV, 3 (2%) Bethesda II, 1 (1%) Bethesda V, and 1 (1%) Bethesda I. Afirma results for 52 of the nodules (45%) were benign, 57 (50%) were suspicious, and 6 (5%) specimens yielded no result because of low messenger RNA content. Three of the benign nodules (6%) were treated surgically, and all were benign on final surgical pathology. Forty-six (81%) of the suspicious nodules were treated surgically; final surgical pathology revealed 30 (65%) were benign and 16 (35%) malignant, yielding a positive predictive value of 35%. Conclusions.— In our experience, 50% of the indeterminate nodules were classified as suspicious by Afirma, with a 35% rate of malignancy in these nodules at surgical resection, in comparison with a historical rate of malignancy at our institution of 11% for Bethesda III nodules and 23% for Bethesda IV. Our use of Afirma is consistent with prior reports in that it has a low positive predictive value in indeterminate thyroid nodules.

Predictive Value of Epileptiform Discharges for Subsequent Epilepsy After Febrile Seizures

2018 ◽  
Vol 33 (12) ◽  
pp. 772-775
Author(s):  
Alja Kavčič ◽  
Zvonka Rener-Primec
Keyword(s):  
Positive Predictive Value ◽  
Epileptic Seizure ◽  
Predictive Value ◽  
Epileptic Seizures ◽  
Febrile Seizures ◽  
Epileptiform Discharges

The predictive value of epileptiform discharges for subsequent epilepsy after febrile seizures was studied in 140 children: 72 children (51%) had simple febrile seizures and 68 children (49%) had complex febrile seizures. Electroencephalography (EEG) was performed in 103 children (74%), it was normal in 66 (47%) and with epileptiform patterns in 37 patients (26%). At follow-up in 2017, 10 children developed epilepsy, 1 had a single epileptic seizure, 9 of them had epileptiform EEGs. Of the patients with normal EEGs after complex febrile seizures, none developed epilepsy, and 92% of patients with normal EEGs after recurrent febrile seizures did not develop epilepsy. Therefore, patients with normal EEGs were unlikely to develop epilepsy. Fifteen percent of patients with complex and 31% of patients with recurrent febrile seizures and epileptiform EEGs developed epileptic seizures. The positive predictive value of epileptiform discharges was low in complex and twice as high in recurrent febrile seizures.

Diagnosis of cerebral hemorrhage before the era of computed tomography

2013 ◽  
Vol 154 (44) ◽  
pp. 1743-1746
Author(s):  
Gergely Hofgárt ◽  
Rita Szepesi ◽  
Bertalan Vámosi ◽  
László Csiba
Keyword(s):  
Computed Tomography ◽  
Cerebrospinal Fluid ◽  
Positive Predictive Value ◽  
Predictive Value ◽  
Hemorrhagic Stroke ◽  
Cranial Computed Tomography ◽  
Cerebral Stroke ◽  
Daily Routine ◽  
Stroke Patients ◽  
The Difference

Introduction: During the past decades there has been a great progress in neuroimaging methods. Cranial computed tomography is part of the daily routine now and its use allows a fast diagnosis of parenchymal hemorrhage. However, before the availability of computed tomography the differentiation between ischemic and hemorrhagic stroke was based on patient history, physical examination, percutan angiography and cerebrospinal fluid sampling, and the clinical utility could be evaluated by autopsy of deceased patients. Aim: The authors explored the diagnostic performance of cerebrospinal fluid examination for the diagnosis of ischemic and hemorrhagic stroke. Method: Data of 200 deceased stroke patients were retrospectively evaluated. All patients had liquor sampling at admission and all of them had brain autopsy. Results: Bloody or yellowish cerebrospinal fluid at admission had a positive predictive value of 87.5% for hemorrhagic stroke confirmed by autopsy, while clear cerebrospinal fluid had positive predictive value of 90.7% for ischemic stroke. Patients who had clear liquor, but autopsy revealed hemorrhagic stroke had higher protein level in the cerebrospinal fluid, but the difference was not statistically significant (p = 0.09). Conclusions: The results confirm the importance of pathological evaluation of the brain in cases deceased from cerebral stroke. With this article the authors wanted to salute for those who contributed to the development of the Hungarian neuropathology. In this year we remember the 110th anniversary of the birth, and the 60th anniversary of the death of professor Kálmán Sántha. Professor László Molnár would be 90 years old in 2013. Orv. Hetil., 154 (44), 1743–1746.

VALUE OF COMBINATION OF HAP SCORE AND BISAP SCORE IN PREDICTING SEVERITY IN PATIENTS OF ACUTE PANCREATITIS

2019 ◽  
pp. 96-100
Author(s):  
Thi Ngoc Suong Le ◽  
Pham Chi Tran ◽  
Van Huy Tran
Keyword(s):  
Acute Pancreatitis ◽  
Positive Predictive Value ◽  
Roc Curve ◽  
Predictive Value ◽  
Prognostic Value ◽  
Acute Inflammation ◽  
Clinical Symptoms ◽  
Mortality Rates ◽  
Multiple Organ ◽  
Central Hospital

Acute pancreatitis (AP) is an acute inflammation of the pancreas, usually occurs suddenly with a variety of clinical symptoms, complications of multiple organ failure and high mortality rates. Objectives: To determine the value of combination of HAP score and BISAP score in predicting the severity of acute pancreatitis of the Atlanta 2012 Classification. Patients and Methods: 75 patients of acute pancreatitis hospitalized at Hue Central Hospital between March 2017 and July 2018; HAP and BISHAP score is calculated within the first 24 hours. The severity of AP was classified by the revised Atlanta criteria 2012. Results: When combining the HAP and BISAP scores in predicting the severity of acute pancreatitis, the area under the ROC curve was 0,923 with sensitivity value was 66.7%, specificity value was 97.1%; positive predictive value was 66.7%, negative predictive value was 97.1%. Conclusion: The combination of HAP and BISAP scores increased the sensitivity, predictive value, and prognostic value in predicting the severity of acute pancreatitis of the revised Atlanta 2012 classification in compare to each single scores. Key words: HAPscore, BiSAP score, acute pancreatitis, predicting severity

Predictive value of CA 19-9 in patients with pancreatic tumours

2020 ◽  
Vol 14 (1) ◽  
pp. 45-48
Author(s):  
Faiza Abrar ◽  
Adnan Riaz ◽  
Kaukab Sultana ◽  
Tariq Feroz Khawaja
Keyword(s):  
Surgical Resection ◽  
Predictive Value ◽  
Local Population ◽  
Pancreatic Disease ◽  
International Studies ◽  
Malignant Tumours ◽  
Pancreatic Tumours ◽  
Benign Pathology ◽  
Pancreatic Tumour ◽  
Age Range

Background: Pancreatic carcinoma is a disease with high modality and has a high incidence of recurrence after surgical resection. The prognosis depends on early diagnosis and treatment. Numerous international studies have reported use of CA 19-9 in diagnosis of pancreatic cancer. We planned this study to validate role of CA 19-9 in our local population. The objective of this study is to correlate raised serum CA 19-9 levels in patients with pancreatic tumours to distinguish between benign and malignant pancreatic disease. Subjects and methods: The present study is a validation study. Thirty-five patients with diagnosis of pancreatic tumor on radiological imaging were included after their informed consent. Data collection forms were filled, blood samples were taken and serum CA 19-9 was estimated by ELISA in Biochemistry department, SIMS. Histopathology samples were collected at time of surgical resection, sent to pathology departments of respective hospitals and histopathological reports collected. All data was collected and analysed by using descriptive method. The study was conducted in Biochemistry department of PGMI and SIMS, Lahore from May 2015 till June 2016. Results: Out of 35 patients, nineteen (54.3%) were female and sixteen (45.7%) were male. Thirty [85.7%] patients were between third to seventh decades of their life. The mean age range around 47.28. Thirty-four patients had malignant tumor and 1 benign on histopathology. CA 19-9 was raised (>37 U/ml) in 33 out of 34 patients with malignant pathology. The patient with benign pathology had CA 19-9 level <37U/ml (the cut off value). Head of pancreas was the commonest site in 32 patients (65%) for tumour occurrence. Total 28 (82%) patients had adenocarcinoma as the histological type of pancreatic tumour. Cholangiocarcinoma in Periampullary region of pancreas was second in frequency, 4 patients (12%). CA 19-9 shows sensitivity of 97% and specificity of 100% to diagnose carcinoma of pancreas in patients with pancreatic tumour. CA 19-9 has 100% positive predictive value to diagnose benign tumour and 50% negative predictive value to diagnose malignant tumours. Conclusion: Raised levels of CA 19-9 has an important role in diagnosis of patients with pancreatic tumour to differentiate between benign and malignant pathology.

scholarly journals Accuracy of MSCT Coronary Angiography with 64 Row CT Scanner—Facing the Facts

2010 ◽  
Vol 4 ◽  
pp. CMC.S3864 ◽  
Author(s):  
M. Wehrschuetz ◽  
E. Wehrschuetz ◽  
H. Schuchlenz ◽  
G. Schaffler
Keyword(s):  
Coronary Artery Disease ◽  
Coronary Artery ◽  
Coronary Angiography ◽  
Positive Predictive Value ◽  
Diagnostic Accuracy ◽  
Predictive Value ◽  
Diagnostic Potential ◽  
Coronary Artery Stenoses ◽  
Artery Disease ◽  
Msct Angiography

Improvements in multislice computed tomography (MSCT) angiography of the coronary vessels have enabled the minimally invasive detection of coronary artery stenoses, while quantitative coronary angiography (QCA) is the accepted reference standard for evaluation thereof. Sixteen-slice MSCT showed promising diagnostic accuracy in detecting coronary artery stenoses haemodynamically and the subsequent introduction of 64-slice scanners promised excellent and fast results for coronary artery studies. This prompted us to evaluate the diagnostic accuracy, sensitivity, specificity, and the negative und positive predictive value of 64-slice MSCT in the detection of haemodynamically significant coronary artery stenoses. Thirty-seven consecutive subjects with suspected coronary artery disease were evaluated with MSCT angiography and the results compared with QCA. All vessels were considered for the assessment of significant coronary artery stenosis (diameter reduction ≥ 50%). Thirteen patients (35%) were identified as having significant coronary artery stenoses on QCA with 6.3% (35/555) affected segments. None of the coronary segments were excluded from analysis. Overall sensitivity for classifying stenoses of 64-slice MSCT was 69%, specificity was 92%, positive predictive value was 38% and negative predictive value was 98%. The interobserver variability for detection of significant lesions had a κ-value of 0.43. Sixty-four-slice MSCT offers the diagnostic potential to detect coronary artery disease, to quantify haemodynamically significant coronary artery stenoses and to avoid unnecessary invasive coronary artery examinations.

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