3T MRI of wrist ligaments and TFCC using true plane oblique 3d T2 Dual Echo Steady State (DESS) – a study of diagnostic accuracy

Objectives: This study was designed to assess the accuracy of unenhanced 3T MRI supplemented with dedicated true plane reformats of 3d T2DESS, in assessing tears of scapholunate, lunotriquetral ligaments and triangular fibrocartilage complex, using arthroscopy as gold standard. Methods: In a retrospective cohort review, patients who underwent wrist arthroscopy and MRI over 2 years (n=46) were identified. Dedicated axial and coronal reformats were obtained from 3d T2 DESS sequence for assessing intrinsic ligaments and TFCC. At arthroscopy tears were classified using Geissler’s classification and compared to MRI findings. Results: The sensitivity of unenhanced 3T MRI in detecting scapholunate ligament tears was 87% and specificity was 90% and negative predictive value of 93%. The lunate triquetral ligament was assessed with a high specificity (97%) and negative predictive value (93%), sensitivity was 63%. Triangular fibrocartilage (TFCC) tears were assessed with a sensitivity of 100%. The overall diagnostic accuracy of unenhanced 3T MRI of wrist in detecting ligament tears was 91%. Conclusion: 3T wrist MRI with dedicated reformats from 3d T2 DESS have a high diagnostic accuracy in assessing acute intrinsic ligament and TFCC injuries. High strength 3T MRI with good technical quality isotropic 3d T2 DESS is critical for accurate wrist ligament assessment. Negative predictive values of 3T MRI of 95% can lead to reduced need for diagnostic arthroscopy of the wrist. Advances in knowledge: This study assesses the diagnostic performance of unenhanced 3T MRI with 3dT2 DESS in assessing traumatic wrist ligament tears. The accuracy of T2 DESS in wrist imaging has not been previously reported.

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Diagnostic accuracy of history taking, physical examination and imaging for non-chronic finger, hand and wrist ligament and tendon injuries: a systematic review update

BMJ Open ◽

10.1136/bmjopen-2020-037810 ◽

2020 ◽

Vol 10 (11) ◽

pp. e037810

Author(s):

Patrick Krastman ◽

Nina M C Mathijssen ◽

Sita M A Bierma-Zeinstra ◽

Gerald A Kraan ◽

Jos Runhaar

Keyword(s):

Physical Examination ◽

Diagnostic Accuracy ◽

Predictive Value ◽

Tendon Injuries ◽

Cochrane Library ◽

Supporting Evidence ◽

History Taking ◽

Triangular Fibrocartilage ◽

Diagnostic Work ◽

Wrist Ligament

ObjectiveThe diagnostic work-up for ligament and tendon injuries of the finger, hand and wrist consists of history taking, physical examination and imaging if needed, but the supporting evidence is limited. The main purpose of this study was to systematically update the literature for studies on the diagnostic accuracy of tests for detecting non-chronic ligament and tendon injuries of the finger, hand and wrist.MethodsMedline, Embase, Cochrane Library, Web of Science, Google Scholar ProQuest and Cinahl were searched from 2000 up to 6 February 2019 for identifying studies. Methodological quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies 2 checklist, and sensitivity (Se), specificity (Sp), accuracy, positive predictive value (PPV) and negative predictive value (NPV) were extracted.ResultsNone of the studies involved history taking. Physical examination, for diagnosing lesions of the triangular fibrocartilage complex (TFCC), showed Se, Sp, accuracy, PPV and NPV ranging from 58% to 90%, 20% to 69%, 56% to 73%, 53% to 71% and 55% to 65%, respectively. Physical examination in hand and finger injuries the Se, Sp, accuracy, PPV and NPV ranged from 88% to 99%, 75% to 100%, 34% to 88%, 91% to 100% and 75% to 95%, respectively. The accuracy of MRI with high-resolution (3 T) techniques for TFCC and interosseous ligaments of the proximal carpal row ranged from 89% to 91% and 75% to 100%, respectively. The accuracy of MRI with low-resolution (1.5 T) techniques for TFCC and interosseous ligaments of the proximal carpal row ranged from 81% to 100% and 67% to 95%, respectively.ConclusionsThere is limited evidence on the diagnostic accuracy of history taking and physical examination for non-chronic finger, hand and wrist ligament and tendon injuries. Although some imaging modalities seemed to be acceptable for the diagnosis of ligament and tendon injuries in the wrist in patients presenting to secondary care, there is no evidence-based advise possible for the diagnosis of non-chronic finger, hand or wrist ligament and tendon injuries in primary care.

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Clinico sonological and laboratory co-relation with histopathology of acute appendicitis to develop new diagnostic scoring system (Yash scoring system)

International Surgery Journal ◽

10.18203/2349-2902.isj20173211 ◽

2017 ◽

Vol 4 (8) ◽

pp. 2556 ◽

Cited By ~ 3

Author(s):

Yashwant R. Lamture ◽

Harshal Ramteke ◽

R. K. Shinde ◽

Vinay V. Shahapurkar ◽

Varsha P. Gajbhiye

Keyword(s):

Positive Predictive Value ◽

Diagnostic Accuracy ◽

Negative Predictive Value ◽

Predictive Value ◽

Scoring System ◽

Imaging Techniques ◽

Scoring Systems ◽

Negative Appendectomy ◽

Predictive Values ◽

Prospective Comparison

Background: Of the many scoring systems currently available, the modified Alvarado scoring system (MASS) is the most widely employed, because of its ability to reduce negative appendectomy rate (NAR). Unfortunately, this system is more accurate in western population. In spite of the advances in the diagnostic and imaging techniques NAR have not decreased much. This clearly indicates the need of development of new diagnostic scoring system so we have developed new diagnostic scoring system (Yash Score). The objective of this study was to develop and study diagnostic accuracy of new diagnostic scoring system (Yash scoring system) for acute appendicitis.Methods: A prospective comparison YSS and MASS was done on 418 patients. Depending on clinical judgement appendicectomy was done. Sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy for YSS and MASS were calculated using SPSS 17.0 statistical software for statistical analysis and compared using Chi-square test.Results: The sensitivity and specificity of YSS was found to be 99.48 per cent and 92.86 percent respectively. The sensitivity and specify of MASS was 52.05 per cent and 100 per cent respectively. The positive predictive value and negative predictive value of YSS was 99.48 per cent and 92.86 per cent respectively. Negative and positive predictive values of MASS were 13.02% and 100% respectively.Conclusions: Comparison in between YSS and MASS in the present study shows significant statistical difference.

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Comparison between MRI and Arthroscopy of the Wrist for the Assessment of Posttraumatic Lesions of Intrinsic Ligaments and the Triangular Fibrocartilage Complex

Journal of Wrist Surgery ◽

10.1055/s-0041-1729757 ◽

2021 ◽

Author(s):

Sergio De Santis ◽

Roberto Cozzolino ◽

Riccardo Luchetti ◽

Lucia Cazzoletti

Keyword(s):

Triangular Fibrocartilage Complex ◽

Ligament Injury ◽

Wrist Arthroscopy ◽

Mri Imaging ◽

Likelihood Ratios ◽

Mri Findings ◽

Level Of Evidence ◽

Predictive Values ◽

Arthroscopic Findings ◽

Triangular Fibrocartilage

Abstract Background Magnetic resonance imaging (MRI) has been considered the most appropriate examination for wrist ligament injuries diagnosis, but it frequently fails to assess the intrinsic ligament lesion. Therefore, wrist arthroscopy is required to enhance and define the diagnosis. Purpose We compare the MRI imaging with wrist arthroscopy for intrinsic wrist ligaments (scapholunate [SL] and lunotriquetral [LT]) and triangular fibrocartilage complex (TFCC) injuries detection. Patients and Methods From 2007 to 2014, 532 patients affected by suspected SL, LT, and TFCC posttraumatic ligament injury have been investigated by 1.5-Tesla MRI and wrist arthroscopy. Inclusion and exclusion criteria were adopted. Only for SL ligament injury, the arthroscopic findings of complete (stage IV) and partial (stages I–III) SL ligament injury were compared with MRI findings. Statistical analysis, including sensitivity, specificity, positive and negative predictive values, positive and negative likelihood ratios, and the diagnostic odds ratio, was used to compare MRI with arthroscopic findings. Results A total of 146 patients were accepted in the study. In 68 cases of arthroscopic SL ligament lesion, MRI confirmed the diagnosis only in 50% of the cases. In partial SL lesions, MRI was positive in 24.3% and in complete SL lesions, MRI was positive in 80.6% of the cases. In 10 cases of arthroscopic LT ligament lesion, MRI was positive in 30.0% of the cases. In 33 patients with arthroscopic TFCC lesion, MRI was positive in 66.7% of the cases. Conclusion 1.5-T MRI demonstrated to fail in confirming the lesion of SL, LP, and TFCC ligaments respectively in 50, 70, and 33.3% of the cases positive at arthroscopy. In complete SL ligament lesion, MRI reaches a higher sensitivity than in partial lesion. Arthroscopy remains the best method to demonstrate the ligament lesion and obtain more information regarding the extent and quality of the ligament damage. Level of Evidence This is a Level II, retrospective comparative study.

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Prognostic value of inflammatory markers for detecting anastomotic leakage after esophageal resection

BMC Surgery ◽

10.1186/s12893-020-00995-2 ◽

2020 ◽

Vol 20 (1) ◽

Author(s):

Lukas F. Liesenfeld ◽

Peter Sauer ◽

Markus K. Diener ◽

Ulf Hinz ◽

Thomas Schmidt ◽

...

Keyword(s):

Diagnostic Accuracy ◽

Anastomotic Leakage ◽

Negative Predictive Value ◽

Predictive Value ◽

Inflammatory Markers ◽

Prognostic Value ◽

Predictive Marker ◽

Esophageal Resection ◽

Predictive Values ◽

Sensitivity Specificity

Abstract Background Early diagnosis of anastomotic leakage (AL) after esophageal resection is crucial for the successful management of this complication. Inflammatory serological markers are indicators of complications during the postoperative course. The aim of the present study was to evaluate the prognostic value of routine inflammatory markers to predict anastomotic leakage after transthoracic esophageal resection. Methods Data from all consecutive patients undergoing transthoracic esophageal resection between January 2010 and December 2016 were analyzed from a prospective database. Besides clinicodemographic parameters, C-reactive protein, white blood cell count and albumin were analyzed and the Noble/Underwood (NUn) score was calculated to evaluate their predictive value for postoperative anastomotic leakage. Diagnostic accuracy was measured by sensitivity, specificity, and negative and positive predictive values using area under the receiver operator characteristics curve. Results Overall, 233 patients with transthoracic esophageal resection were analyzed, 30-day mortality in this group was 3.4%. 57 patients (24.5%) suffered from AL, 176 patients were in the AL negative group. We found significant differences in WBCC, CRP and NUn scores between patients with and without AL, but the analyzed markers did not show an independent relevant prognostic value. For CRP levels below 155 mg/dl from POD3 to POD 7 the negative predictive value for absence of AI was > 80%. Highest diagnostic accuracy was detected for CRP levels on 4th POD with a cut-off value of 145 mg/l reaching negative predictive value of 87%. Conclusions In contrast to their prognostic value in other surgical procedures, CRP, WBCC and NUn score cannot be recommended as independent markers for the prediction of anastomotic leakage after transthoracic esophageal resection. CRP is an accurate negative predictive marker and discrimination of AL and no-AL may be helpful for postoperative clinical management. Trial registration The study was approved by the local ethical committee (S635-2013).

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Evaluation of Diagnostic Accuracy of the Approved Tumor Mapping Protocol in Grading of Glial Tumors

Journal of Contemporary Medical Sciences ◽

10.22317/jcms.v6i5.844 ◽

2020 ◽

Vol 6 (5) ◽

Author(s):

Nahid Sadighi ◽

Sima Fallah Arzpeyma ◽

Mohsen Izanlou ◽

Mohamad Ali Oghabian ◽

Mostafa Izanlou ◽

...

Keyword(s):

Diagnostic Accuracy ◽

Negative Predictive Value ◽

Predictive Value ◽

High Grade Glioma ◽

Target Area ◽

High Grade ◽

Predictive Values ◽

Glial Tumors ◽

High Grade Gliomas ◽

Sensitivity Specificity

Objective: Evaluation of Diagnostic Accuracy of the Approved Tumor Mapping Protocol in Grading of Glial Tumors. Methods: This descriptive cross-sectional study was performed on patients aged 2 to 82 years with glial tumor. Patients were referred to the hospital for tumor mapping and underwent imaging with simultaneous methods of MRS and magnetic resonance (MR) perfusion and conventional MRI under the supervision of NIAG group. Then, the results of the second evaluation, including the ratios of the desired metabolites and the amount of blood flow, permeability of the target area were compared with the results of pathology. The results were analyzed by SPSS software version 24. Results: In this study, 30 patients were included. Sensitivity, specificity, positive and negative predictive value for the determination of high-grade glioma with peripheral/internal rCBV were 100/100%, 100/93%, 93/100% and 100.100%, respectively. Sensitivity, specificity, positive and negative predictive value for the diagnosis of glioma by using peripheral/internal rCBV and thresholds of 2.65 and 1.06 were 100/100%, 93/100%, 93/100% and 100/100%, respectively. Sensitivity, specificity, positive predictive value and negative predictive value were determined for diagnosis of high-grade glioma tumor using Ch + Cr / NAA Cho / Cr and Cho / NAA ratios with detection threshold of 2.97 (93.3%), 3.5 (78.9%,100%, 100%, and 73.3%), and 2.1 (100%). Threshold values of 3.5, 2.1 and 2.97 were obtained using Cho / Cr, Ch + Cr / NAA and Cho / NAA, respectively, for the detection of high-grade gliomas. The combination of rCBV, Cho / Cr, Ch + Cr / NAA and Cho / NAA had sensitivity, specificity, positive and negative predictive value of 67.7%, 80%, 77% and 70.5%, respectively. Significant differences in rCBV and Cho / Cr, Cho / NAA and NAA / Cr ratios were observed between low- and high-grade gliomas (P <0.0001). Conclusion: Preoperative grading of glioma based on routine MR imaging is often unreliable. As a result, measuring rCBV and Cho / Cr and Cho / NAA ratios independently and somewhat together can significantly improve the sensitivity and predictive values of preoperative glioma grading.

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Accuracy of Rotator Cuff Tears and Tendinosis Diagnoses on Shoulder Ultrasound Performed by a Short-experienced Operator

American Journal of Sonography ◽

10.25259/ajs-22-2018 ◽

2018 ◽

Vol 1 ◽

pp. 9

Author(s):

Harshad Arvind Vanjare ◽

Jyoti Panwar

Keyword(s):

Rotator Cuff ◽

Negative Predictive Value ◽

Rotator Cuff Tear ◽

Predictive Value ◽

Rotator Cuff Tears ◽

Mri Findings ◽

Cuff Tear ◽

Experienced Operator ◽

Magnetic Resonance Imaging Mri ◽

Sensitivity Specificity

Objective The objective of the study was to assess the accuracy of ultrasound examination for the diagnosis of rotator cuff tear and tendinosis performed by a short experienced operator, compared to magnetic resonance imaging (MRI) results. Method A total of 70 subjects suspected to have rotator cuff tear or tendinosis and planned for shoulder MRI were included in the study. Shoulder ultrasound was performed either before or after the MRI scan on the same day. Ultrasound operator had a short experience in performing an ultrasound of the shoulder. Ultrasound findings were correlated to MRI findings. Results Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for the diagnosis of tendinosis were 58%, 84%, 63%, 80%, and 75%, respectively, and it was 68%, 91%, 73%, 88%, and 85%, respectively, for the diagnosis of rotator cuff tear. Conclusions Sensitivity for diagnosing rotator cuff tear or tendinosis was moderate but had a higher negative predictive value. Thus, the ultrasound operator with a short experience in performing shoulder ultrasound had moderate sensitivity in diagnosing tendinosis or tears; however, could exclude them with confidence.

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Screening for aneurysms of the abdominal aorta using a simple screening device

The Ultrasound Journal ◽

10.1186/s13089-020-00192-5 ◽

2020 ◽

Vol 12 (1) ◽

Author(s):

J. W. Brakel ◽

T. A. Berendsen ◽

P. M. C. Callenbach ◽

J. van der Burgh ◽

R. J. Hissink ◽

...

Keyword(s):

Negative Predictive Value ◽

Sensitivity And Specificity ◽

Abdominal Aorta ◽

Predictive Value ◽

Cost Effective ◽

Abdominal Ultrasound ◽

Predictive Values ◽

Bladder Scan ◽

Health Council ◽

Screening Device

Abstract Introduction Several countries advocate screening for aneurysms of the abdominal aorta (AAA) in selected patients. In the Netherlands, routine screening is currently under review by the National Health Council. In any screening programme, cost-efficiency and accuracy are key. In this study, we evaluate the Aorta Scan (Verathon, Amsterdam, Netherlands), a cost-effective and easy-to-use screening device based on bladder scan technology, which enables untrained personnel to screen for AAA. Methods We subjected 117 patients to an Aorta Scan and compared the results to the gold standard (abdominal ultrasound). We used statistical analysis to determine sensitivity and specificity of the Aorta Scan, as well as the positive and negative predictive values, accuracy, and inter-test agreement (Kappa). Results Sensitivity and specificity were 0.86 and 0.98, respectively. Positive predictive value was 0.98 and negative predictive value was 0.88. Accuracy was determined at 0.92 and the Kappa value was 0.85. When waist–hip circumferences (WHC) of > 115 cm were excluded, sensitivity raised to 0.96, specificity stayed 0.98, positive and negative predictive value were 0.98 and 0.96, respectively, accuracy to 0.97, and Kappa to 0.94. Conclusion Herein, we show that the Aorta Scan is a cost-effective and very accurate screening tool, especially in patients with WHC below 115 cm, which makes it a suitable candidate for implementation into clinical practice, specifically in the setting of screening selected populations for the presence of AAA.

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Influence of lesion location on the accuracy of CT derived FFR: head-to-head comparison with invasive FFR

European Heart Journal ◽

10.1093/ehjci/ehaa946.0158 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

M Moshage ◽

S Smolka ◽

S Achenbach ◽

F Ammon ◽

P Ferstl ◽

...

Keyword(s):

Coronary Angiography ◽

Positive Predictive Value ◽

Diagnostic Accuracy ◽

Negative Predictive Value ◽

Predictive Value ◽

Invasive Coronary Angiography ◽

Roc Curve Analysis ◽

Jude Medical ◽

Lesion Location ◽

Distal Vessel

Abstract Background The accuracy of CT-derived FFR (FFRCT) has been repeatedly reported. However, the influence of lesion location on accuracy is unknown. Therefore, we evaluated the diagnostic accuracy of FFRCT to detect lesion-specific ischemia and determined the influence of lesion location (proximal vs. distal vessel segments) compared to invasively measured FFR in patients with suspected CAD. Methods A total of 136 vessels in which “Dual-Source”-CT coronary angiography had been performed due to suspected CAD and who were further referred for invasive coronary angiography with invasive FFR measurement within three months of the index CT examination were retrospectively identified and screened for inclusion in this analysis. Patients with either left main coronary artery stenoses, bifurcation or ostial stenoses were excluded. Invasive FFR was measured using a pressure wire (CERTUS®, St. Jude Medical, Minnesota, USA or Verrata®, Volcano, San Diego, USA). FFRCT was calculated using an on-site prototype (cFFR Version 3.0, Siemens Healthineers, Forchheim, Germany). All vessels were analyzed by an experienced observer blinded to the results of invasive FFR. Stenoses with invasively measured FFR ≤0.80 were classified as hemodynamically significant. We evaluated the diagnostic accuracy of FFRCT in proximal vs. non-proximal vessel segments. Proximal lesions included stenoses located in segment one, six, eleven and twelve. All other stenoses were categorized as distal lesions. Results Out of 136 coronary stenoses, 47 (35%) were located in proximal segments and 89 (65%) lesions were located in distal segments. Compared to invasive FFR, the sensitivity of FFRCT to correctly identify/exclude hemodynamically significant stenoses in proximal vessel segments was 93% (95% CI: 68–99.8%) and the specificity was 100% (95% CI: 89–100%), compared to a sensitivity of 72% (95% CI: 46.5–90%) and a specificity of 87% (95% CI: 77–94%) for FFRCT in distal lesions. The positive predictive value was 100% and the negative predictive value was 97% (95% CI: 82.8–99.5%) compared to a positive predictive value of 59% (95% CI: 42–93.9%) and a negative predictive value of 93% (95% CI: 85.4–96.3%) for proximal vs. distal vessel segment, respectively. This corresponds to an accuracy of 98% vs. 84%, respectively (p=0.02). ROC-Curve analysis showed a slightly higher – albeit non-significant – area under the curve for FFRCT to detect hemodynamic relevance in proximal lesions compared to distal lesions (AUC 0.95, p<0.001 vs. AUC: 0.86, p<0.001, respectively, p=0.2). Conclusion FFRCT obtained using an on-site prototype shows overall a high diagnostic accuracy for detecting lesions causing ischemia as compared to invasive FFR with a trend towards better diagnostic performance in proximal vessel segments. Funding Acknowledgement Type of funding source: None

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Foundational Statistical Principles in Medical Research: Sensitivity, Specificity, Positive Predictive Value, and Negative Predictive Value

Medicina ◽

10.3390/medicina57050503 ◽

2021 ◽

Vol 57 (5) ◽

pp. 503

Author(s):

Thomas F. Monaghan ◽

Syed N. Rahman ◽

Christina W. Agudelo ◽

Alan J. Wein ◽

Jason M. Lazar ◽

...

Keyword(s):

Positive Predictive Value ◽

Negative Predictive Value ◽

Predictive Value ◽

Medical Literature ◽

Disease Prevalence ◽

Positive Test Result ◽

Predictive Values ◽

Sensitivity Specificity ◽

Test Result ◽

Test Probability

Sensitivity, which denotes the proportion of subjects correctly given a positive assignment out of all subjects who are actually positive for the outcome, indicates how well a test can classify subjects who truly have the outcome of interest. Specificity, which denotes the proportion of subjects correctly given a negative assignment out of all subjects who are actually negative for the outcome, indicates how well a test can classify subjects who truly do not have the outcome of interest. Positive predictive value reflects the proportion of subjects with a positive test result who truly have the outcome of interest. Negative predictive value reflects the proportion of subjects with a negative test result who truly do not have the outcome of interest. Sensitivity and specificity are inversely related, wherein one increases as the other decreases, but are generally considered stable for a given test, whereas positive and negative predictive values do inherently vary with pre-test probability (e.g., changes in population disease prevalence). This article will further detail the concepts of sensitivity, specificity, and predictive values using a recent real-world example from the medical literature.

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Sensitivity and Negative Predictive Value of Motor Evoked Potentials of the Facial Nerve

Journal of Neurological Surgery Part A Central European Neurosurgery ◽

10.1055/s-0040-1719026 ◽

2021 ◽

Author(s):

Nicolas Bovo ◽

Shahan Momjian ◽

Renato Gondar ◽

Philippe Bijlenga ◽

Karl Schaller ◽

...

Keyword(s):

Facial Nerve ◽

Evoked Potentials ◽

Negative Predictive Value ◽

Patient Group ◽

Vestibular Schwannoma ◽

Predictive Value ◽

Cerebellopontine Angle ◽

Motor Evoked Potentials ◽

Vestibular Schwannomas ◽

Predictive Values

Abstract Objective The objective of this study was to determine the performance of the standard alarm criterion of motor evoked potentials (MEPs) of the facial nerve in surgeries performed for resections of vestibular schwannomas or of other lesions of the cerebellopontine angle. Methods This retrospective study included 33 patients (16 with vestibular schwannomas and 17 with other lesions) who underwent the resection surgery with transcranial MEPs of the facial nerve. A reproducible 50% decrease in MEP amplitude, resistant to a 10% increase in stimulation intensity, was applied as the alarm criterion during surgery. Facial muscular function was clinically evaluated with the House–Brackmann score (HBS), pre- and postsurgery at 3 months. Results In the patient group with vestibular schwannoma, postoperatively, the highest sensitivity and negative predictive values were found for a 30% decrease in MEP amplitude, that is, a criterion stricter than the 50% decrease in MEP amplitude criterion, prone to trigger more warnings, used intraoperatively. With this new criterion, the sensitivity would be 88.9% and the negative predictive value would be 85.7%. In the patient group with other lesions of the cerebellopontine angle, the highest sensitivity and negative predictive values were found equally for 50, 60, or 70% decrease in MEP amplitude. With these criteria, the sensitivities and the negative predictive values would be 100.0%. Conclusion Different alarm criteria were found for surgeries for vestibular schwannomas and for other lesions of the cerebellopontine angle. The study consolidates the stricter alarm criterion, that is, a criterion prone to trigger early warnings, as found previously by others for vestibular schwannoma surgeries (30% decrease in MEP amplitude).

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