Skip to main content
The Egyptian Journal of Otolaryngology
Download PDF
  • Original Article
  • Open access
  • Published:

Determinants of Cormack–Lehane grading for glottic exposure in microlaryngeal surgery in Middle Delta Egyptian patients

The Egyptian Journal of Otolaryngology volume 40, Article number: 123 (2024) Cite this article

Abstract

Background

Laryngoscopy is a diagnostic procedure utilized in critical care to examine and visualize the larynx through the diversion of upper airway structures. Its primary functions are airway management and tracheal intubation. The objective of this study was to detect the predictors of laryngeal exposure during microlaryngeal surgery (MLS).

Methods

An analytical cross-sectional study was conducted on a consecutive sample of 100 patients presenting laryngeal lesions that were trans-orally microsurgeries to treat various glottic diseases (biopsies revealed 68% benign lesions such as vocal fold polyps, cysts, and nodules, and 32% glottic masses) and prepared for MLS.

Results

This study included 100 patients presenting laryngeal lesions from both sexes with the age of 47.0 ± 14.7 years, in multivariate logistic regression analysis, all these parameters were significant predictors for Cormack–Lehane and Italian Grading (P < 0.05). Body mass index (BMI) (OR = 3.449, 95% CI = 2.463–8.187), mandibular protrusion test (OR = 2.981, 95% CI = 1.922–4.044), mento-sternal length (OR = 3.722, 95% CI = 1.980–7.794), and atlanto-occipital joint (AOJ) extension (OR = 1.572, 95% CI = 1.865–4.263). Cormack–Lehane and Italian Grading was significantly associated with BMI, mandibular protrusion test, Mallampati Index, mento-thyroid, mento-sternal length, and AOJ extension, it increased with BMI of > 35, with more protruded mandible (class C), higher Mallampati Index (class III) and shorter mento-sternal distance (≤ 12.5 cm).

Conclusions

During microlaryngeal surgery, BMI, mandibular protrusion test, Mallampati Index, mento sternal and AOJ extension were significant predictors of Cormack–Lehane and Italian Grading which makes it easier for laryngeal exposure.

Background

The larynx is a fibro-cartilaginous tube located in the front of the neck, above the trachea. It plays an important role in deglutition, by extending from the tip of the epiglottis to the lower border of the cricoid cartilage [1, 2].

Laryngoscopy is a procedure that involves visualizing and examining the larynx by manipulating the upper airway structures. It is commonly used for tracheal intubation and airway management in critical care settings, as well as in cases of trauma, cancer, laryngeal inflammation, and vocal fold paralysis [3].

Anesthesiologists first introduced the difficult airway concept and emphasized the need for a precise preoperative assessment to prevent possible challenges during orotracheal intubation and lower the occurrence of life-threatening complications [4].

Several factors such as short neck, stiff, muscular neck, macroglossia, retrognathia, obesity, and limitation of the cervical spine that could predict difficult laryngeal exposure (DLE) have been investigated [5].

The objective of this study was to detect the predictors of laryngeal exposure during microlaryngeal surgery (MLS).

Methods

An analytical cross-sectional study was conducted on 100 consecutive patients with laryngeal lesions who had transoral microsurgery for various glottic illnesses, with 68% having benign lesions as vocal fold polyps, cysts, nodules, and 32% glottic masses for biopsies) and prepared for MLS. The research was conducted from December 2019 to December 2022 after acceptance from the Ethical Committee at Tanta University Hospitals in Tanta, Egypt. (approval code: 33,474/11/19). Patients were provided an informed written consent.

The criteria for exclusion were patients with co-morbidities that interfere with general anesthesia, patients with definite cervical spine problems such as vertebral fixation, spinal stenosis, and vertebral subluxation), patients undergone previous neck radiation in the last year and patients subjected to partial laryngectomy.

All patients underwent history taking, examination [clinical parameters (general parameters, teeth, and mouth parameters, oropharyngeal parameters and neck parameters), general parameters (body mass index (BMI)], teeth and mouth parameters (inter-incisors gap (IIG), mouth opening (MO), mandibular protrusion test and mandibular arch configuration(, oropharynx parameters) Mallampati’s score and mento-hyoid distance (MHD), neck parameters (atlanto-occipital joint extension degree (AOJ), neck circumference (color size), neck length: medial and lateral neck length (MNL and LNL) and mento-sternal distance (MSD), and radiological parameters as lateral digital X-ray neck.

Body mass index

Measured by weight (kg) over height square (M2). BMI = W (kg)/H (M2), achieved a score of 0 when > 25 kg/m2, scored 1 when 25–35 kg/m2, and scored 2 when ≥ 35 kg/m2.

Teeth and mouth parameters

Inter-incisor gap: its measurement is taken with the mouth completely open, between the upper and lower teeth in patients with teeth, and between the upper and lower gums in patients without teeth [6].

Mouth opening

Measured painlessly by expanding the mouth to the maximum extent between the incisal margins of the upper central incisors and the incisal edges of the lower central incisors [7].

Mandibular protrusion test

Considered as the position of the lower incisors related to the upper incisors [8].

Mandibular arch configuration

Considered as the inter-second molar width [9]. In males scored 0 if 46.5–49 mm and scored 1 if < 46.5 mm. Females scored 0 if 45.5–48 mm and scored 1 if < 45.5 mm.

Mallampati’s score

The oropharyngeal view was evaluated using Mallampati’s score, which included instructing the patient to sit, open their mouth as wide as possible, and stick out their tongue without making any sound. The classification is based on this assessment. Class I: hard palate, soft palate, uvula, tonsil pillars visible (score 0). Class II: hard palate, soft palate, uvula visible (score 1). Class III: hard palate, soft palate, and base of uvula visible (score 2). Class IV: only hard palate visible (score 3) [10].

Mento-hyoid distance (MHD)

Measured along a straight line from the lower border of the mandibular symphysis (chin) to the hyoid bone with the head fully extended and categorized as grade I: < 4 cm (2.5 fingers), normally scored 0, grade II: 4–6 cm (2.5–3.5 fingers) scored 1 and grade III: < 6 cm (< 3.5 fingers) scored 2 [11].

AOJ extension degree

Extending the AOJ is essential for the patient to achieve the optimal intubating position, ensuring alignment of the oral, pharyngeal, and laryngeal axes. This can be evaluated by assessing movement while the patient is seated with the head and neck in a neutral position facing forward, and then with the joint maximally extended. Grade I: < 35°, scored 0; grade II: 34°–22°, scored 1; grade III: 21°–12°, scored 2; grade IV: < 12°, scored 3 [12, 13] (Fig. 1).

Fig. 1
figure 1

Atlanto-occipital joint extension degree

Full size image

Neck circumference (collar size)

Neck circumference is measured just below the laryngeal prominence [5]. Males < 37 cm, normally scored 0, ≥ 37 cm scored 1, and females < 34 cm, normally scored 0, ≥ 34 cm scored 1 (Fig. 2).

Fig. 2
figure 2

Neck circumference measurement

Full size image

Medial neck length

Measured from the superior aspect of the hyoid bone to the jugular notch [14]. Medial neck length scored 0 when quantified 8–10 cm. Scored 1 when quantified < 8 cm. Scored 2 when quantified > 10 cm (Fig. 3).

Fig. 3
figure 3

Medial neck length measurement

Full size image

Lateral neck length

Measured from the mandibular angle to the mid-portion of the ipsilateral clavicle [14]. Lateral neck length scored 0 when measured 12.5–14 cm. Scored 1 when measured < 12.5 cm. Scored 2 when measured > 14 cm (Fig. 4).

Fig. 4
figure 4

Lateral neck length measurement

Full size image

Mento-sternal distance (MSD)

The measurement is taken in centimeters from the mentum to the sternal notch with the head in full extension and the lips closed. If the measurement is more than 12.5 cm, it is scored as 0 (normal). If it is less than or equal to 12.5 cm, it is scored as 1 [15] (Fig. 5).

Fig. 5
figure 5

Mento-sternal measurement

Full size image

Lateral digital X-ray neck

By measuring MHD and mento-thyroid distance digitally over digital X-rays using radiology computer software. The radiological mento-hyoid distance is measured on lateral cervical X-ray films in the neutral position as the distance between the hyoid bone and the tip of the chin in millimeters using radiology computer software. It is graded as grade I if < 40 mm (scored 0), grade II if 40–60 mm (scored 1), and grade III if < 60 mm (scored 2). The radiological mento-thyroid distance is measured on a lateral cervical X-ray film in the neutral position as the distance in millimeters between the thyroid cartilage and the point of the chin using radiology computer software. It is graded as grade I < 60 mm normally scored 0, grade II if 60–65 mm scored 1, and grade III if < 65 mm (scored 2). Each patient was intubated and placed in the traditional Boyce–Jackson sniffing posture while under general anesthesia (Fig. 6).

Fig. 6
figure 6

Lateral cervical X-ray film in the neutral position as the mento-hyoid distance is the distance between the hyoid bone and the tip of the chin in millimeters (yellow arrow) and the mento-thyroid distance is the distance between the thyroid cartilage and the tip of the chin (orange arrow)

Full size image

A Storz laryngoscope was inserted and held in place using the rod and ring chest support. The larynx was evaluated using an operating microscope, and necessary operations were performed [16]. The sniffing position is usually seen as the best head position for direct laryngoscopy, aligning the oropharyngeal, pharyngeal, and laryngeal axes. Good laryngeal exposures were classified as grades I and II, whereas problematic or impossible laryngeal exposures were classified as classes III and IV [3] (Fig. 7).

Fig. 7
figure 7

A Left, B right vocal fold nodule Cormack–Lehane grade I, the entire glottis is completely visible by large-bore laryngoscopes in the Boyce–Jackson position without external laryngeal counter pressure

Full size image

(A) Left vocal fold nodule Cormack–Lehane grade I, the entire glottis is completely visible by large-bore laryngoscopes in the Boyce–Jackson position without external laryngeal counter pressure, (B) left glottic mass for biopsy Cormack–Lehane grade II, visualization of the anterior (AC) by large-bore laryngoscope but with some modification as external counter pressure, (C) Right glottic mass for biopsy Cormack grade III visualization of the anterior 2/3 of the vocal fold, and (D) left vocal fold mass for biopsy Cormack–Lehane grade IV, only the arytenoids or very posterior part of the vocal folds are visible (Fig. 8).

Fig. 8
figure 8

A Left vocal fold nodule Cormack–Lehane grade I, the entire glottis is completely visible by large-bore laryngoscopes in the Boyce–Jackson position without external laryngeal counter pressure, B left glottic mass for biopsy Cormack–Lehane grade II, visualization of the anterior (AC) by large-bore laryngoscope but with some modification as external counter pressure, C Right glottic mass for biopsy Cormack grade III visualization of the anterior 2/3 of vocal fold, and D left vocal fold mass for biopsy Cormack–Lehane grade IV, only the arytenoid

Full size image

The primary outcome was to analyze laryngeal exposure patterns in Egyptian patients and evaluate difficulty in laryngeal exposure during microlaryngeal surgery using various tests to determine the correlation between difficult exposure and specific tests while the secondary outcomes were to correlate difficult intubation by the anesthesiologist with a DLE for the ear, nose, and throat (ORL) surgeon and to ascertain whether surgical experience could affect score validity because DLE has been reported to be related to difficult intubation, but the impact of the surgeon’s experience has never been studied.

Statistical analysis

The statistical analysis was conducted using SPSS v26 (IBM Inc., Chicago, IL, USA). Quantitative variables were shown as mean and standard deviation (SD) and compared between the two groups using the post hoc Tukey test. Qualitative variables were shown as frequency and percentage (%) and examined using the chi-square test. Multiple regression was used to determine the connection between a dependent variable and many independent variables. A two-tailed P value less than 0.05 was deemed statistically significant.

Results

The distribution of the studied cases according to demographic data, BMI, and diagnosis are shown in Table 1.

Table 1 Distribution of the studied cases according to demographic data, BMI
Full size table

The distribution of the studied patient’s mouth, tooth, oro-pharynx, and neck examination is shown in Table 2.

Table 2 Distribution of the studied patient’s mandibular measurements, oro-pharynx, and neck examination
Full size table

Distribution of the studied patients according to Cormack–Lehane and Italian Grading and neck examination radiologically are shown in Table 3.

Table 3 Distribution of the studied patients according to Cormack–Lehane and Italian Grading and neck examination radiologically
Full size table

Cormack–Lehane and Italian Grading was significantly associated with BMI, mandibular protrusion test, Mallampati Index, mento-thyroid, mento-sternal length, and AOJ extension, it increased with BMI of > 35, with more protruded mandible (class C), higher Mallampati Index (class III) and shorter mento-sternal distance (≤ 12.5 cm) and decreased with higher AOJ extension (class II) (Table 4).

Table 4 Relation between Cormack–Lehane and Italian Grading with BMI, mandibular protrusion test, oro-pharynx examination, and neck examination
Full size table

In multivariate logistic regression analysis, all these parameters were significant predictors for Cormack–Lehane and Italian Grading (P value < 0.001, 0.024, 0.001, and 0.001 respectively). BMI (OR = 3.449, 95% CI = 2.463–8.187), mandibular protrusion test (OR = 2.981, 95% CI = 1.922–4.044), mento-sternal length (OR = 3.722, 95% CI = 1.980–7.794) and AOJ extension (OR = 1.572, 95% CI = 1.865–4.263) (Table 5).

Table 5 Multivariate analysis logistic regression for Cormack–Lehane and Italian Grading
Full size table

Discussion

The surgeon’s primary objective during microlaryngoscopy is to establish the optimal exposure to observe the larynx, and to maximize functional success during phono surgery, this will lower the risk of local recurrence following laryngeal cancer excision [17].

Our findings showed that Cormack–Lehane and Italian Grading was significantly associated with BMI, it increased with BMI of > 35. Obesity can lead to changes in the airway anatomy that make intubation more difficult. These changes include a larger neck circumference, increased soft tissue in the neck, and a higher risk of sleep apnea, all of which can impede the visualization of the laryngeal structures during intubation [18]. Similar to our findings Lundstrøm et al. [19] reported that high BMI was a statistically significant indicator of difficult intubation.

Our findings showed that Cormack–Lehane and Italian Grading were significantly associated with the inter-incisor gap. The Cormack–Lehane classification and the Italian Laryngeal View grading are both associated with the inter-incisor gap, as a smaller IIG can indicate more difficulty in visualizing the glottis during laryngoscopy. This association is clinically significant, as it can aid in predicting difficult laryngoscopy and intubation, ultimately guiding airway management strategies [20].

Like our findings, Piazza et al. [4] analyzed data that showed a statistically significant correlation between the inter-incisor gap and DLE: IIG.

Regarding the mandibular protrusion test in our study, class A patients represented 86.0% of all the study Egyptian patients, class B patients represented 8.0% and class C patients represented 6.0%.

Our study showed that Cormack–Lehane and Italian Grading was significantly related to the mandibular protrusion test, it increased with a more protruded mandible (class C). This was consistent with findings from the study carried out by El-Radaideh et al. [21] which showed a significant association between Cormack–Lehane grading and the mandibular protrusion test.

Mandibular arch configuration in our study was abnormal in 51% of the patients and normal in the remaining 49% of the patients, it ranged from 45.0 to 49.0 with a mean ± SD of 46.6 ± 1.1 in males and from 45.0 to 48 with a mean ± SD of 46.6 ± 1.3 in females.

Regarding the Mallampati Index in our research, 45% of patients were classified as Mallampati class I, 18% as class II, 33% as class III, and 4% as class IV. Class III and class IV were predicted for difficult intubation. Findings in this study demonstrated that Cormack–Lehane and Italian Grading were significantly related to the Mallampati Index. This was consistent with our findings from the study carried out by El-Radaideh et al. [21] showed a statistically significant association between the Cormack–Lehane grading and the Mallampati Index.

Regarding Cormack–Lehane and Italian Grading, our study showed that the major percentage was of grade I (38%). Kar et al. [22] showed that the majority were of grade I as well but with a higher percentage than our findings (58.7%).

Our study showed that the majority of participants (63%) were in grades I and II. Similar to our findings kar et al. [22] reported the majority to be in grades I and II but with a higher percentage (91.4%).

Findings in this study demonstrated that there was no significant association between Cormack–Lehane and Italian Grading and this is like findings by Ohri et al. [23] observed no statistically significant association among them as well.

Our study showed that Cormack–Lehane and Italian Grading was significantly associated with AOJ Extension, 88% were grade I, 12% were grade II it decreased with higher AOJ extension (grade II). This was consistent with findings from Gupta et al. [24] showed that the Cormack–Lehane grade increases with decreased angle of AOJ extension.

The neck circumference in our study of all 100 Egyptian patients was ≥ 34 cm in females and ≥ 37 cm in females. Pinar et al. [5] showed that neck circumference showed statistical significance in the correlation analysis in his study.

The mento-thyroid distance, our study showed that majority of participants (94%) had mento-thyroid distance of > 6.5 cm, (4%) had mento-thyroid distance of 6–6.5 cm and (2%) less than 6 cm, most of them (40.42%) were of grade I according to Cormack–Lehane and Italian Grading. Like our findings, Reddy et al. [25] reported that most studied patients had an MSD of ≤ 5.7 cm (95%) but most of them were of grade II according to Cormack–Lehane grading.

Our study showed that Cormack–Lehane and Italian Grading was significantly related to mento-thyroid length and it increased with shorter mento-sternal distance (≤ 6.5 cm). Like our findings, Maha et al. [26] reported that there was a statistically significant association between Cormack–Lehane grading and mento-thyroid distance.

Regarding MSD, our study showed that the majority of participants (91%) had MSD of > 12.5 cm and most of them (41.75%) were of grade I according to Cormack–Lehane and Italian Grading. Like our findings, Reddy et al. [25] reported that the majority of studied patients had an MSD of > 12.5 cm (96%) but the majority of them were of grade II according to Cormack–Lehane grading.

Regarding difficulty in laryngeal exposure, our study showed that Cormack–Lehane and Italian Grading were significantly related to mento-sternal length.

In our study, about 71% of the total percent considered as good exposure (grade I and grade II) in Cormack–Lehane and Italian Grading while 29% considered as difficult exposure (grades III, IV, and V).

In our study, radiological mento-hyoid distance is about 40–60 mm in (64%) of our patients and > 60 mm in (36%).

Our study radiological mento-thyroid distance is about < 60 mm in (2%) of our patients, 60–65 mm in (4%), and > 65 mm in (94%). Koirala et al. [27] showed that radiologically measuring the thyro-mental distance is a reliable predictor of difficult intubation in both the general population and surgical patients.

Therefore, different variables associated with this grading (Cormack–Lehane and Italian Grading) are also associated with DLE. This includes a BMI of > 35, a more protruded mandible (class C), a higher Mallampati Index (class III), shorter mento-sternal distance (≤ 12.5 cm), and decreased with higher AOJ extension (class II) and shorter mento-thyroid distance (< 6 cm). In line with our results, Kharat et al. [28] reported that increased Mallampati grade and MSD are statistically significantly associated with more difficulty in laryngeal exposure.

Study limitations were a single-center study done in only one setting. No control group was used in this study so, this study could not be a cohort study.

Conclusions

During microlaryngeal surgery, BMI, mandibular protrusion test, Mallampati Index, mento-sternal, and AOJ extension were significant predictors of Cormack–Lehane and Italian Grading which make it easier for laryngeal exposure.

Availability of data and materials

The datasets used and analyzed during the current study are available from the corresponding author on reasonable request.

References

  1. Ganaw AEA, Ehfeda M, Shaikh N, Lance M, Chanda AH, Belkair AOM et al (2019) Role of virtual endoscopy and 3-D reconstruction in airway assessment of critically Ill patients. Patient Saf Surg 240:117–128

    Google Scholar 

  2. Yokota T, Mukaigawa T, Yasunaga Y, Ogawa H, Onoe T, Yurikusa T et al (2023) Multidisciplinary tumor board for head and neck cancer from the perspective of medical oncologists—optimizing its effectiveness. Front Oncol 13:903–910

    Article  Google Scholar 

  3. Collins SR (2014) Direct and indirect laryngoscopy: equipment and techniques. Respir Care 59:850–862

    Article  PubMed  Google Scholar 

  4. Piazza C, Mangili S, Bon FD, Paderno A, Grazioli P, Barbieri D et al (2014) Preoperative clinical predictors of difficult laryngeal exposure for microlaryngoscopy: the Laryngoscore. Laryngoscope 124:2561–2567

    Article  PubMed  Google Scholar 

  5. Pinar E, Calli C, Oncel S, Selek B, Tatar B (2009) Preoperative clinical prediction of difficult laryngeal exposure in suspension laryngoscopy. Eur Arch Otorhinolaryngol 266:699–703

    Article  PubMed  Google Scholar 

  6. Merah NA, Wong DT, Ffoulkes-Crabbe DJ, Kushimo OT, Bode CO (2005) Modified Mallampati test, thyromental distance and inter-incisor gap are the best predictors of difficult laryngoscopy in West Africans. Can J Anaesth 52:291–296

    Article  PubMed  Google Scholar 

  7. Karkouti K, Rose DK, Wigglesworth D, Cohen MM (2000) Predicting difficult intubation: a multivariable analysis. Can J Anaesth 47:730–739

    Article  CAS  PubMed  Google Scholar 

  8. Nanda M, Singla A, Negi A, Jaj HS, Mahajan V (2012) The association between maxillomandibular sagittal relationship and pharyngeal airway passage dimensions. JIOS 46:48–52

    Article  Google Scholar 

  9. Al-Zubair NM (2013) The relationship between mandibular arch length and widths in a sample of Yemeni subjects with normal dento-Skeletal relationship. J Orthod Sci 2:120–123

    Article  PubMed  PubMed Central  Google Scholar 

  10. Eldin MS, Yehia A, Abdallah R, Shalaby G, Abdelaziz M (2023) Prevalence of obstructive sleep apnea in patients with difficult intubation: looking for evidence? J Orthod Sci 72:14–18

    Google Scholar 

  11. Gupta S, Rajesh D, Kr S, Jain D (2004) Airway assessment: predictors of difficult airway. Indian J Anaesth 49:70–78

    Google Scholar 

  12. Swain BP, Nag DS, Samaddar DP, Swain A, Srividhya BP, Dua SK (2017) Does miller straight blade and paraglossal technique provide better laryngoscopy than traditional macintosh blade standard technique-a comparative study? MEJ Anesth 24:111–118

    Google Scholar 

  13. Bellhouse CP, Doré C (1988) Criteria for estimating likelihood of difficulty of endotracheal intubation with the Macintosh laryngoscope. Anaesth Intensive Care 16:329–337

    Article  CAS  PubMed  Google Scholar 

  14. Han TS, Oh MK, Kim SM, Yang HJ, Lee BS, Park SY et al (2015) Relationship between neck length, sleep, and cardiovascular risk factors. Korean J Fam Med 36:10–21

    Article  PubMed  PubMed Central  Google Scholar 

  15. Vaswani JP, Wadhwa S, Prathyusha Y, Vondivillu S, Vyas VH (2022) Comparison of predictive value of upper lip bite test ratio of height to thyromental distance and Mallampati classification for the anticipation of difficult intubation in apparently normal patients. J Res Innov Anesth 7:37–41

    Article  Google Scholar 

  16. Fernandez-Vaquero MA, Charco-Mora P, Garcia-Aroca MA, Greif R (2023) Preoperative airway ultrasound assessment in the sniffing position: a prospective observational study. Braz J Anesthesiol 73:539–547

    PubMed  Google Scholar 

  17. Chang CF, Chu PY (2017) Predictors of local recurrence of glottic cancer in patients after transoral laser microsurgery. J Chin Med Assoc 80:452–457

    Article  PubMed  Google Scholar 

  18. Liew WJ, Negar A, Singh PA (2022) Airway management in patients suffering from morbid obesity. Saudi J Anaesth 16:314–321

    Article  PubMed  PubMed Central  Google Scholar 

  19. Lundstrøm LH, Møller AM, Rosenstock C, Astrup G, Wetterslev J (2009) High body mass index is a weak predictor for difficult and failed tracheal intubation: a cohort study of 91,332 consecutive patients scheduled for direct laryngoscopy registered in the Danish Anesthesia Database. Anesthesiol 110:266–274

    Article  Google Scholar 

  20. Harjai M, Alam S, Bhaskar P (2021) Clinical relevance of mallampati grading in predicting difficult intubation in the era of various new clinical predictors. Cureus 13:e16396

    PubMed  PubMed Central  Google Scholar 

  21. El-Radaideh K, Dheeb E, Shbool H, Garaibeh S, Bataineh A, Khraise W et al (2020) Evaluation of different airway tests to determine difficult intubation in apparently normal adult patients: undergoing surgical procedures. Patient Saf Surg 14:43–55

    Article  PubMed  PubMed Central  Google Scholar 

  22. Kar S, Senapati LK, Samanta P, Satapathy GC (2022) Predictive value of modified mallampati test and upper lip bite test concerning cormack and lehane’s laryngoscopy grading in the anticipation of difficult intubation: a cross-sectional study at a tertiary care hospital, bhubaneswar, india. Cureus 14:e28754

    PubMed  PubMed Central  Google Scholar 

  23. Ohri R (2020) Correlation between clinical methods of airway assessment and modified cormack -lehane grading. J Anesth 710:15–29

    Google Scholar 

  24. Gupta K, Gupta PK (2010) Assessment of difficult laryngoscopy by electronically measured maxillo-pharyngeal angle on lateral cervical radiograph: a prospective study. Saudi J Anaesth 4:158–162

    Article  PubMed  PubMed Central  Google Scholar 

  25. Reddy PB, Punetha P, Chalam KS (2016) Ultrasonography - a viable tool for airway assessment. Indian J Anaesth 60:807–813

    Article  PubMed  PubMed Central  Google Scholar 

  26. Mostafa M, Saeed M, Hasanin A, Badawy S, Khaled D (2020) Accuracy of thyromental height test for predicting difficult intubation in elderly. J Anesth 34:217–223

    Article  PubMed  Google Scholar 

  27. Koirala S, Shakya BM, Marhatta MN (2020) Comparison of upper lip bite test with modified mallampati test and thyromental distance for prediction of difficult intubation. NJMS 5:2–9

    Google Scholar 

  28. Kharrat I, Achour I, Trabelsi JJ, Trigui M, Thabet W, Mnejja M et al (2022) Prediction of difficulty in direct laryngoscopy. Sci Rep 12:10722–10730

    Article  CAS  PubMed  PubMed Central  Google Scholar 

Download references

Acknowledgements

Not applicable.

Funding

Not to be declared.

Author information

Authors and Affiliations

  1. Otorhinolaryngology Department, Kafr El Sheikh General Hospital, Kafr El Sheikh, Egypt

    Ahmed Zakaria Mahmoud

  2. Otorhinolaryngology Department, Faculty of Medicine, Tanta University, Tanta, Egypt

    Mohamed Adel Khalifa, Hassan Moustafa Hegazy & Emad Mohammed Shehata

Authors
  1. Ahmed Zakaria Mahmoud
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Mohamed Adel Khalifa
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Hassan Moustafa Hegazy
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Emad Mohammed Shehata
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

All authors contributed to the study’s conception and design. Material preparation, data collection, and analysis were performed by A. Z. M., M. A. K., and H. M. H. The first draft of the manuscript was written by E. M. S. All authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.

Corresponding author

Correspondence to Ahmed Zakaria Mahmoud.

Ethics declarations

Ethics approval and consent to participate

The research was conducted from December 2019 to December 2022 after acceptance from the Ethical Committee at Tanta University Hospitals in Tanta, Egypt. (approval code: 33474/11/19). Patients were provided an informed written consent.

Consent for publication

Not applicable.

Competing interests

The authors declare that they have no competing interests.

Additional information

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Mahmoud, A.Z., Khalifa, M.A., Hegazy, H.M. et al. Determinants of Cormack–Lehane grading for glottic exposure in microlaryngeal surgery in Middle Delta Egyptian patients. Egypt J Otolaryngol 40, 123 (2024). https://doi.org/10.1186/s43163-024-00694-2

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1186/s43163-024-00694-2

Keywords