Thyromental Height Research Articles

Evaluation of Upper Lip Bite Test and Thyromental Height Test for Prediction of Difficult Laryngoscopy

Background and Aims: Unanticipated difficult laryngoscopy (DL) can cause life-threatening complications in the operation theatre, intensive care unit and emergency department. Various screening tests have been developed to predict DL. While modified Mallampati test (MMT) is the most commonly used one, it has poor sensitivity. Upper lip bite test (ULBT) and thyromental height test (TMHT) have been shown to be more reliable in predicting DL. The aim of this study was to compare the three tests and evaluate whether a combination of ULBT and TMHT would show better accuracy in predicting DL. Patients and Methods: A total of 109 adult patients undergoing elective surgery under general anaesthesia with endotracheal intubation were assessed using the MMT, ULBT and TMHT before surgery. The required sample size for the study was calculated using the Fisher Z test. The three tests, and a combination of ULBT with TMHT, were compared for their sensitivity, specificity, positive predictive value, negative predictive value and accuracy in predicting DL. Results: The accuracy of MMT, ULBT, TMHT and ULBT + TMHT in predicting DL was found to be 81.65%, 86.23%, 97.24% and 95.41%, respectively. MMT exhibited the lowest sensitivity and had the highest number of false negatives. TMHT exhibited the best accuracy and sensitivity, with the lowest number of false negatives. A combination of ULBT and TMHT did not improve the PPV in the sample tested. Conclusion: TMHT was found to be the best test for predicting DL, and its combination with ULBT did not improve the accuracy.

Evaluation of thyromental height as a predictor of difficult laryngoscopy and difficult intubation: a cross-sectional observational study

Background and objectivesSeveral anthropometric measurements have been suggested to identify a potentially difficult airway. We studied thyromental height (TMH) as a predictor of difficult laryngoscopy and difficult intubation. We also compared TMH, ratio of height to thyromental distance (RHTMD), and thyromental distance (TMD) as predictors of difficult airway. MethodsThis cross-sectional observational study was conducted in 300 adult surgical patients requiring tracheal intubation. Preoperatively airway characteristics were assessed. Standard anesthesia was administered. Degree of difficulty with mask ventilation, laryngoscopic view, duration of laryngoscopy, and difficulty in tracheal intubation (intubation difficulty scale score) were noted. Multivariate logistics regression analysis was performed to identify independent predictors for difficult laryngoscopy. ResultsLaryngoscopy was difficult in 46 of 300 (15.3%) patients; all 46 patients had Cormack-Lehane grade 3 view. Duration of laryngoscopy was 27........11...s in patients with difficult laryngoscopy and 12.7........3.9...s in easy laryngoscopy; p...=...0.001. Multivariate analysis identified that TMH, presence of short neck, and history of snoring were independently associated with difficult laryngoscopy. Incidence of difficult intubation was 17.0%. A shorter TMH was associated with higher IDS scores; r...=...-0.16, p...=...0.001. TMH and duration of laryngoscopy were found to be negatively correlated; a shorter TMH was associated with a longer duration of laryngoscopy; r...=...-0.13, p...=...0.03. The cut-off threshold value for TMH in our study is 4.4 cm with a sensitivity of 66% and a specificity of 54%. ConclusionThyromental height predicts difficult laryngoscopy and difficult intubation.TMD and RHTMD did not prove to be useful as predictors of difficult airway.

Development and validation of a difficult laryngoscopy prediction model using machine learning of neck circumference and thyromental height

BackgroundPredicting difficult airway is challengeable in patients with limited airway evaluation. The aim of this study is to develop and validate a model that predicts difficult laryngoscopy by machine learning of neck circumference and thyromental height as predictors that can be used even for patients with limited airway evaluation.MethodsVariables for prediction of difficulty laryngoscopy included age, sex, height, weight, body mass index, neck circumference, and thyromental distance. Difficult laryngoscopy was defined as Grade 3 and 4 by the Cormack-Lehane classification. The preanesthesia and anesthesia data of 1677 patients who had undergone general anesthesia at a single center were collected. The data set was randomly stratified into a training set (80%) and a test set (20%), with equal distribution of difficulty laryngoscopy. The training data sets were trained with five algorithms (logistic regression, multilayer perceptron, random forest, extreme gradient boosting, and light gradient boosting machine). The prediction models were validated through a test set.ResultsThe model’s performance using random forest was best (area under receiver operating characteristic curve = 0.79 [95% confidence interval: 0.72–0.86], area under precision-recall curve = 0.32 [95% confidence interval: 0.27–0.37]).ConclusionsMachine learning can predict difficult laryngoscopy through a combination of several predictors including neck circumference and thyromental height. The performance of the model can be improved with more data, a new variable and combination of models.

Study comparing different airway assessment tests in predicting difficult laryngoscopy: A prospective study in geriatric patients.

Background and Aims:Limited studies are available comparing diagnostic accuracy of various airway predictors in geriatric patients. We conducted this study with primary aim to evaluate and validate the predictive value of 'standard airway predictors' like modified Mallampati test, thyromental distance (TMD), sternomental distance, neck movement (NM), mouth opening (MO), dentition and 'new airway predictors' like upper lip bite test (ULBT), ratio of height to thyromental distance and thyromental height test (TMHT) for predicting difficult laryngoscopy in geriatric patients.Methods:This prospective, observational study was conducted on 140 patients above 65 years of age of either sex, scheduled for elective surgery under general anaesthesia requiring endotracheal intubation. The age, weight, height, body mass index (BMI) and airway parameters were recorded. The laryngoscopic view was assessed by modified Cormack-Lehane scale. Standard formulae were used to calculate validity indexes.Results:The incidence of difficult larygoscopy found in our study was 25%. The mean age of our study population was 69.37 ± 4.23 years. TMD exhibited the highest sensitivity (80%) and negative predictive value (NPV) (91.86%) as compared to other studied airway predictors. The positive predictive value (PPV) of ULBT was 100%. Moreover, ULBT exhibited highest accuracy (82.14%) and odds ratio (86.88) and high specificity (91.30%) for predicting difficult laryngoscopy in geriatric patients. NM and TMHT also exhibited high accuracy (77.85%, 77.14%) and PPV (59.09%, 52.94%).Conclusions:TMD and ULBT both showed good predictive value in diagnosing difficult laryngoscopy in geriatric patients. Furthermore, NM and TMHT also exhibited higher diagnostic accuracy in predicting difficult airway in these patients.

Assessment of the Thyromental Height Test as an Effective Airway Evaluation Tool

Assessment of the Thyromental Height Test as an Effective Airway Evaluation Tool

Comparison of modified Mallampati test and thyromental height test for preoperative airway assessment: A prospective observational study

Background: Prevision of a potentially difficult airway in the preoperative period is imperative. The available tools are evaluation of mouth opening, Mallampati test; atlanto-occipital extension; hyomental, thyromental, and sternomental distances; and upper lip bite test; thyromental height test (TMHT) is a new indicator. Aims: To compare the effectiveness of preoperative anaesthetic airway evaluation methods of TMHT and Modified mallampati test (MMT) to predict the difficulty in intubation. Materials and Methods: A prospective observational study was aimed to compare the effectiveness of preoperative anesthetic airway evaluation methods of TMHT and modified Mallampati test (MMT) to predict the difficulty in intubation. A total of 150 subjects were included in this study. MMT and TMHT were compared, and sensitivity, specificity, predictive values, and accuracy were calculated. Results: On comparison, we found TMHT to be more sensitive (93.33%) than MMT (77.78%); both tests have high specificity (TMHT 91.43%; MMT 81.90%). Positive predictive value was 82.35% for TMHT and 64.81% for MMT. Similarly, negative predictive value was 96.97% for TMHT and 89.58% for MMT. Accuracy was 92.00% for TMHT and 80.66% for MMT. Conclusions: TMHT can predict difficult intubation better than MMT (high positive predictive value). However, both TMHT and MMT predict easy intubations effectively, their negative predictive values being high.

Eficácia do escore simplificado preditivo de dificuldade de intubação e da altura tiromentoniana em cirurgias de cabeça e pescoço: estudo observacional

Background and objectivesIn this study, we aimed to investigate the predictive value of different airway assessment tools, including parts of the Simplified Predictive Intubation Difficulty Score (SPIDS), the SPIDS itself and the Thyromental Height Test (TMHT), in intubations defined as difficult by the Intubation Difficulty Score (IDS) in a group of patients who have head and neck pathologies. MethodsOne hundred fifty‐three patients who underwent head and neck surgeries were included in the study. The Modified Mallampati Test (MMT) result, Thyromental Distance (TMD), Ratio of the Height/Thyromental Distance (RHTMD), TMHT, maximum range of head and neck motion, and mouth opening were measured. The SPIDSs were calculated, and the IDSs were determined. ResultsA total of 25.4% of the patients had difficult intubations. SPIDS scores > 10 had 86.27% sensitivity, 71.57% specificity and 91.2% Negative Predictive Value (NPV). The results of the Receiver Operating Curve (ROC) analysis for the airway screening tests and SPIDS revealed that the SPIDS had the highest area under the curve; however, it was statistically similar to other tests, except for the MMT. ConclusionsThe current study demonstrates the practical use of the SPIDS in predicting intubation difficulty in patients with head and neck pathologies. The performance of the SPIDS in predicting airway difficulty was found to be as efficient as those of the other tests evaluated in this study. The SPIDS may be considered a comprehensive, detailed tool for predicting airway difficulty.

Effectiveness of simplified predictive intubation difficulty score and thyromental height in head and neck surgeries: an observational study

Background and objectivesIn this study, we aimed to investigate the predictive value of different airway assessment tools, including parts of the Simplified Predictive Intubation Difficulty Score (SPIDS), the SPIDS itself and the Thyromental Height Test (TMHT), in intubations defined as difficult by the Intubation Difficulty Score (IDS) in a group of patients who have head and neck pathologies. MethodsOne hundred fifty-three patients who underwent head and neck surgeries were included in the study. The Modified Mallampati Test (MMT) result, Thyromental Distance (TMD), Ratio of the Height/Thyromental Distance (RHTMD), TMHT, maximum range of head and neck motion and mouth opening were measured. The SPIDSs were calculated, and the IDSs were determined. ResultsA total of 25.4% of the patients had difficult intubations. SPIDS scores >10 had 86.27% sensitivity, 71.57% specificity and 91.2% Negative Predictive Value (NPV). The results of the Receiver Operating Curve (ROC) analysis for the airway screening tests and SPIDS revealed that the SPIDS had the highest area under the curve; however, it was statistically similar to other tests, except for the MMT. ConclusionsThe current study demonstrates the practical use of the SPIDS in predicting intubation difficulty in patients with head and neck pathologies. The performance of the SPIDS in predicting airway difficulty was found to be as efficient as those of the other tests evaluated in this study. The SPIDS may be considered a comprehensive, detailed tool for predicting airway difficulty.

The Evaluation of Thyromental Height Test as a Single, Accurate Predictor of Difficult Laryngoscopy.

Thyromental Height Test is a relatively new, easy method considered as a more accurate predictor of difficult laryngoscopy than existing methods. The aim of this study was to evaluate its accuracy in predicting difficult laryngoscopy as compared to commonly used methods. This hospital based, cross-sectional, observational study was conducted on 246 patients scheduled for surgery under general anesthesia with endotracheal intubation. Airway assessment was done during pre-anesthetic assessment by Thyromental Height Test, Modified Mallampati Test, Thyromental Distance and Sternomental Distance measurements and predicted as 'difficult' or 'easy' laryngoscopy based on accepted cut-off values. Direct laryngoscopic view was assessed after administration of general anesthesia by a laryngoscopist unaware of the pre-anesthetic assessments and recorded as 'actual' difficult or easy laryngoscopy based on Cormack-Lehane grades. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of each clinical test were determined. Thyromental Height Test had the highest sensitivity (71.42%) and negative predictive value (98.9% respectively) but lowest accuracy (77.2%). Maximum specificity was observed with Thyromental Distance and Sternomental Distance (97.49% each). Thyromental Distance had the highest positive predictive value (25%) and accuracy (95.52%). Thyromental Height Test, with its high sensitivity, is a useful predictor of difficult laryngoscopy. However, due a high number of false positives and relatively low accuracy, it cannot be considered as a sole, reliable and accurate predictor of difficult laryngoscopy.

Thyromental Height Test as a Predictor of Difficult Airway:

Thyromental Height Test as a Predictor of Difficult Airway:

Thyromental Height Test (TMHT) as a Predictor of Difficult Airway in Obese Patients

Thyromental Height Test (TMHT) as a Predictor of Difficult Airway in Obese Patients

Accuracy of thyromental height test for predicting difficult intubation in elderly.

Studies of the accuracy of different airway tests are lacking in elderly. We evaluated and compared the accuracy of thyromental height in predicting difficult intubation in relation to the other traditional airway tests in elderly. We included 120 patients aged ≥ 65years scheduled for general anesthesia with tracheal intubation. Thyromental height, modified Mallampati test, thyromental distance and sternomental distance were evaluated. Cormack-Lehane grade > 2 was considered difficult laryngoscopy. Difficult tracheal intubation was considered if successful intubation required more than 2 attempts. The accuracy of different tests in predicting difficult intubation and difficult laryngoscopy were evaluated through area under receiver operating characteristic (AUROC) curves. Univariate and multivariate analyses were conducted to identify risk factors for difficult intubation and difficult laryngoscopy. Our cohort had a mean age of 71(7) years. We encountered difficult laryngoscopy in 15/120 (12%) patients, difficult intubation in 20/120 (17%) patients, and failed laryngoscopy requiring alternative methods for securing the airway in 3/120 (3%) patients. For predicting difficult intubation, thyromental height and modified Mallampati test showed the highest accuracy AUROC (95% confidence interval): 0.9 (0.83-0.95), cut-off value ≤ 5.9cm, and AUROC (95% confidence interval): 0.89 (0.82-0.94), cut-off value > 2, respectively. Low thyromental height and high modified Mallampati test were the only independent risk factors for difficult laryngoscopy and difficult intubation. In elderly scheduled for elective procedure, both thyromental height and modified Mallampati tests showed good accuracy in predicting difficult intubation and difficult laryngoscopy, whilst thyromental distance and sternomental distance were poor predictors.

Reliability of the thyromental height test for prediction of difficult visualisation of the larynx: A prospective external validation.

Background and Aims:Thyromental height (TMH) has been reported to be useful for prediction of difficult visualisation of the larynx (DVL), defined as Cormack--Lehane (C&L) grade III or IV. The aim of this study was to compare the diagnostic accuracy of the TMH test for DVL with that of other clinically used tests in Japanese patients.Methods:Six hundred and nine surgical patients undergoing endotracheal intubation under general anaesthesia were enrolled in this prospective observational study. TMH, thyromental distance (TMD), and Samsoon and Young's modified Mallampati (MMT) tests were performed in all patients. The C&L grades for the laryngoscopic view with and without external backward, upward, rightward pressure (BURP) were determined by designated airway assessors. The cutoff value for the TMH test was calculated using receiver-operating characteristic (ROC) curve analysis. The sensitivity, specificity, positive predictive value, accuracy, positive likelihood ratio, and area under the ROC curve (AUROC) for each predictive test were calculated and compared.Results:ROC curve analysis indicated that 54 mm is the optimal cutoff value for the TMH test. However, both this value and the conventional cutoff value of 50 mm, which has been reported as having good diagnostic accuracy in the literature, had poor diagnostic accuracy. The AUROC for the TMH test was 0.631 without BURP and 0.592 with BURP; these values were not superior to those for the TMD test or MMT.Conclusion:The TMH test is not a good predictor of DVL in Japanese patients.

Thyromental Height as a Predictor of Difficult Laryngoscopy

Thyromental Height as a Predictor of Difficult Laryngoscopy

Comparison of thyromental height test with ratio of height to thyromental distance, thyromental distance, and modified Mallampati test in predicting difficult laryngoscopy: A prospective study.

Background and Aims:Preoperative airway assessment to predict patients with difficult laryngoscopy is always crucial for anesthesiologists. Several predictive tests have been studied by various authors in quest of finding the best airway predictor. Recently, a new airway predictor, thyromental height test (TMHT) has been reported to have good predictive value in assessing difficult airway. We conducted this study with primary aim to evaluate the diagnostic accuracy of TMHT and to compare it with other established airway predictors, such as ratio of height to thyromental distance (RHTMD), thyromental distance (TMD), and modified Mallampati test (MMT) for predicting difficult laryngoscopy.Material and Methods:This prospective, observational study was conducted in 550 patients of either sex aged >18 years scheduled for elective surgery under general anesthesia. The patients’ airway was assessed preoperatively by two anesthetists. Standard anesthetic protocol was followed in all the patients. The laryngoscopic view was graded according to Cormack–Lehane scale. The receiver operating characteristic (ROC) curve was used to calculate the ideal cut off values for TMHT and RHTMD. Standard formulae were used to calculate validity indexes.Results:The incidence of difficult laryngoscopy was 10%. The cut-off value for TMHT and RHTMD were 5.1 cm and 19.5, respectively. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of TMHT were 78.18%, 93.94%, 58.90%, and 97.48%, respectively. The highest sensitivity, PPV, and NPV were observed with TMHT as compared with RHTMD, TMD, and MMT (P < 0.0001).Conclusions:TMHT is the best predictive test with highest accuracy and odds ratio for predicting difficult airway out of all predictive tests evaluated.

Prediction of difficult airway by thyromental height test- a comparison with modified mallampati test.

Background: Management of airway is central to the Practice of anaesthesia. One of the anaesthesiologist fundamental roles is to maintain a patent airway at a all times.Maintaining a patent airway is essential for adequate oxygenation and ventilation and failure to do so, even for a brief period of time, can be life threatening. Recently, thyromental height test (TMHT) has been proposed as one of the highly sensitive and specific bedside tests to predict difficult airway.Objective: To assess the predictivity of thyromental height test in comparison to modified Mallampati test.Methods: This cross sectional study was carried out in Anesthesiology department of ISMCH during the period of January, 2015 to December, 2016. A total number of 139 consecutive patients scheduled for elective surgical procedure under general anaesthesia requiring intubation having American Society of Anesthesiologists grading I-II. Statistical analyses of the results were obtained by SPSS-20. Sensitivity, specificity, accuracy, positive predictive value and negative predictive value of Thyromental height test and Modified mallampati scoring in diagnosis of difficult airway were calculated.Results: Most (74.4) of the patients belonged to age ≤50 years. Male to female ratio was 1.01:1. Majority 91(65.5%) patients had thyromental height of ≥50 mm. In the diagnosis of difficult airway, Thyromental height test was 92.7% sensitivity, 93.5% specificity, 93.5% accuracy and 85.4% positive predictive values, 97.8% negative predictive value, 13.1% positive likelihood ratio, 0.05 negative likelihood ratio. On the other hand Modified mallampati scoring was 48.8% sensitivity, 92.7% specificity, 79.1% accuracy, 75.0% positive predictive values, 80.2% negative predictive value, 6.7% positive likelihood ratio, 0.55 negative likelihood ratio for prediction of difficult airway.Conclusions: It can be concluded that the thyromental height is useful diagnostic modality for predicting difficult airway.Bangladesh Journal of Medical Science Vol.17(3) 2018 p.455-461

Accuracy of modified thyromental height in predicting difficult laryngoscopy

Objective To evaluate the accuracy of modified thyromental height (MTMH) in predicting difficult laryngoscopy. Methods Two hundred and sixty-three patients of both sexes requiring endotracheal intubation, aged over 17 yr, with body mass index less than 33 kg/m2, of American Society of Anesthesiologists physical status Ⅰor Ⅱ, scheduled for elective surgery under general anesthesia, were selected.The modified Mallampati test (MMT) score, thyromental height (TMH) and MTMH( sniffing thyromental height) were assessed after admission to the operating room.MMT grade Ⅲ or Ⅳ was set as positive predicting index.Direct laryngoscope was placed after induction of anesthesia to expose the glottis, and difficult laryngoscopy was defined as Cormack-Lehane grade Ⅲ or Ⅳ after external laryngeal manipulation.The area under the receiver operating characteristics curve (AUC) was used to evaluate the accuracy of MMT, TMH and MTMH in predicting difficult laryngoscopy. Results Difficult laryngoscopy was found in 24 patients and non-difficult laryngoscopy in 239 patients, the incidence of difficult laryngoscopy was 10.0%, and there were no failed intubations.The AUC (95% confidence interval) of MTMH in predicting difficult laryngoscopy was 0.966 (0.396-0.984), the best cut-off value was 46.83 mm, and Youden index was 0.8456.The sensitivity and specificity of MTMH in predicting difficult laryngoscopy was 91.67% and 92.89%, respectively, and the odds ratio was 143.647.The AUC of MTMH in predicting difficult laryngoscopy was significantly enlarged when compared with that of MMT and TMH (P<0.05). Conclusion MTMH can accurately predict difficult laryngoscopy with the best cut-off value of 46.83 mm in patients. Key words: Thyroid cartilage; Chin; Intubation, intratracheal

Validity of thyromental height test as a predictor of difficult laryngoscopy: A prospective evaluation comparing modified Mallampati score, interincisor gap, thyromental distance, neck circumference, and neck extension.

Background and Aims:Thyromental height test (TMHT) is a recently described anatomical bedside screening tool in predicting difficult laryngoscopy. It has been shown to be more accurate than the modified Mallampati score, thyromental distance (TMD), and sternomental distance with regard to sensitivity and positive predictive value (PPV). Airway assessment studies based on the anatomic parameters of the upper airway are limited in the subcontinent population. We attempted this study to evaluate and validate the predictive value of TMHT at 50 mm in an Indian population in predicting difficult laryngoscopy.Methods:This prospective observational study was conducted in a tertiary teaching hospital on 340 patients. TMHT along with other bedside predictors of difficult intubation, including modified Mallampati score, interincisor gap (IIG), TMD, neck circumference (NC), and neck extension were assessed. We compared the sensitivity, specificity, PPV, negative predictive value (NPV), and diagnostic accuracy of TMHT with other bedside tests such as the modified Mallampati score, IIG, TMD, NC, and neck extension individually in predicting difficult laryngoscopy. Any Cormack and Lehane's intubation grade II b and above was considered to be difficult laryngoscopy.Results:TMHT had the highest sensitivity (84.62%) and specificity (98.97%), and had the most PPV (88%) and NPV (98.63%) when compared with the modified Mallampati score, IIG, TMD, NC, and neck extension. TMHT was followed by the modified Mallampati score and IIG.Conclusion:TMHT appears promising as a single anatomical measure to predict the risk of difficult laryngoscopy, however, validation will require further studies in more diverse patient populations.

Thyromental height test for prediction of difficult laryngoscopy in patients undergoing coronary artery bypass graft surgical procedure.

Background:Patients undergoing coronary artery bypass graft (CABG) procedures have higher incidence of difficult laryngoscopy and intubation than general surgery population. Accurate prediction of difficult laryngoscopy in CABG patients is desirable to reduce the hemodynamic response and myocardial oxygen requirements. Recently, thyromental height test (TMHT) has been proposed as one of the highly sensitive and specific bedside tests to predict difficult airway. We, in our prospective observational study, evaluated the accuracy of the TMHT in predicting difficult laryngoscopy.Methodology:A total of 345 patients undergoing CABG of either sex, in the age group of 35–80 years, American Society of Anesthesiologists 111, undergoing CABG, were studied. Airway assessment was performed with modified Mallampati test with the addition of thyromental distance, sternomental distance, and TMHT. Intraoperatively, direct laryngoscopy was done in accordance with Cormack and Lehane grade of laryngoscopy. The preoperative data and laryngoscopic findings were used together to evaluate the accuracy of TMHT. The sensitivity, specificity, positive and negative predictive values of other three tests were calculated according to standard formula.Results:A total of 345 patients were in the group with mean age of study population at 56.7 (standard deviation 9.1) years (35–80 years). This study showed that almost all tests had good specificity, but sensitivity was poor. However, sensitivity of TMHT was 75% with accuracy of 95%. Receiver operating characteristic curve analysis of TMHT-derived cutoff was 52.17 which increased sensitivity to 81.25% and specificity to 92.3%.Conclusion:TMHT had a higher sensitivity compared to other tests along with good positive and negative predictive value and a very high specificity.

Evaluation of the reliability of preoperative descriptive airway assessment tests in prediction of the Cormack-Lehane score: A prospective randomized clinical study

Study objectiveIn this study we investigated and compared the predictive values of different airway assessments tests including thyromental height measurement test, which has been recently suggested, in difficult laryngoscopy (Cormack and Lehane [C-L] scores 3 and 4). In addition, we compared the effectiveness of methods and C-L scores, by IDS, in terms of predicting difficult intubation. DesignProspective, blinded study. SettingMaltepe University. PatientsFour hundred fifty-one patients selected randomly who underwent general anesthesia. InterventionsIn this study we compared predictive value of thyromental height measurement test (TMH), which has been recently suggested, modified Mallampati test (MMT), upper lip bite test (ULBT), and thyromental distance measurement test (TMD) in difficult laryngoscopy. Final C-L scores were compared with intubation difficulty scale (IDS) in terms of predicting difficult intubation. MeasurementsPatient's American Society of Anesthesiology score, age and weight were recorded. TMH, TMD, MMT, ULBT, IDS and C-L scores were measured and determined. Main resultsThe optimal cut-off point for TMH for predicting difficult laryngoscopy was 43.5 mm and for TMD was 82.06 mm. Use of TMH <43.5 with MMT has the highest sensitivity for predicting difficult intubation (78.38) with 75.36% specificity and 97.50% negative predictive value. TMH showed sensitivity of 91.89% and specificity 52.17% at 50 mm cut-off value. In the comparison of the area under the receiver operating characteristic curve values, none of the tests came forth individually or in combination with MMT test. ConclusionsThe present study demonstrates the practicality of TMH as a digitalized test however the clinical benefits of TMH in daily medical practice are drawn into question. The additional variable of race may have had some bearing on this and further studies, larger in patient sample size, may need to use different methodology concerning age-, sex-, and race-dependent variables in evaluating these tests.