Abstract
There are various subjective as well as objective tools to evaluate the severity of chronic rhinosinusitis (CRS). SNOT-22 is the most commonly used subjective scoring system to determine the severity of CRS. Lund-Mackay (LM) CT scan scoring is widely used as an objective tool in CRS. However LM scores does not correlate well with the subjective tools. We evaluated the modified CT scan scoring system (SN score) for its efficacy in determining the severity of CRS in both subjective as well as objective manner. To correlate the severity of symptoms and CT scan findings in adult patients with chronic rhinosinusitis by estimating the strength of correlation of severity of symptoms of CRS assessed by SNOT-22 scorings with CT scan findings by Lund Mackay scoring system and SN CT scan scoring system. A prospective, observational study was conducted in the tertiary care center from June 2019 to August 2020. The study included 150 adult patients diagnosed with Chronic Rhino Sinusitis resistant to primary medical therapy, who were subjected to CT scan imaging. The symptom severity of CRS was assessed by the SNOT 22 scores. CT scan was done and Lund Mackay scores and SN CT scan scores by the senior author were calculated. The correlation of SNOT 22 score with LM score and Modified CT score were assessed. The correlation of LM score with SNOT 22 score was assessed by plotting Scattered plot diagram, which showed a moderate positive, statistically significant correlation (Person correlation co-efficient: 0.466; p value: 0.032). The correlation of SN CT score with SNOT 22 was assessed by Chi Square test which showed a highly significant, positive correlation (p value of 0.000793). Our study shows a positive correlation of symptoms assessed by SNOT 22 system with radiological findings analyzed by both LM system as well as SN CT scan scoring system. However, SN CT scan scoring system showed a highly significant positive correlation over LM system as it correlates well with symptoms and also provides a grading of disease severity. SN CT scan scoring system can be considered as a tool for assessing the disease severity both in subjective and objective manner. It can be used in place of subjective tools like SNOT 22 for assessing the severity of symptoms in CRS where subjective analysis of the disease is difficult.
Keywords: Chronic rhinosinusitis, Modified CT scan scoring system, Lund-mackay CT scan score, SNOT-22
Introduction
Chronic rhinosinusitis (CRS) in adults is defined as the inflammation of the nose and paranasal sinuses characterized by the set criteria of clinical symptoms, endoscopic signs and CT scan changes [1]. It is a common cause of morbidity and has an effect on the quality of life of patients. A definitive diagnosis and timely intervention can reduce the morbidity significantly. The diagnosis of CRS is based on the symptoms, clinical, endoscopic evaluation and radiologic features [1, 2].
The subjective symptoms and severity of the disease are evaluated by various tools, of which Sino Nasal Outcome Test 22 (SNOT 22) is the commonest as it has a higher sensitivity and is more disease specific [3, 4]. The Lund Mackay (LM) CT scoring system is the most widely used radiologic system for assessment and grading of CRS [5]. Various scoring systems are in vogue and they have tried to evaluate the severity of CRS with the radiological findings. Most of the Radiological scoring systems like LM score have found a poor correlation with subjective tools like SNOT-22 [6–9].
Modified CT scan scoring system (SN score) introduced by Nair S [10] (senior author) analyses CRS in both qualitative and quantitative way by categorizing the disease as per severity, which will help the clinician to take appropriate decision about the management [10].
In this study, we have assessed the correlation of symptoms in CRS with CT scan findings using LM scoring system and SN CT scan scoring system to identify the utility of the same in predicting disease severity.
Material and Methods
A prospective, observational study was conducted in the tertiary care center from June 2019 to August 2020. The study included 150 adult patients diagnosed with CRS resistant to primary medical therapy, who were evaluated with CT scan for further surgical treatment..The patients with fungal sinusitis, sino-nasal tumors, previous nasal surgery and complicated sinusitis were excluded from the study.
The severity of symptoms was assessed using a 22 symptom questionnaire-SNOT 22. Each symptom was scored from 0 to 5 based on the severity and the total score was calculated. The disease was categorized into mild, moderate and severe based on the score [11].
The patients were subjected to CT scan imaging as per standard protocol and acquisition of 3 mm thin axial and coronal scans through paranasal sinuses with special attention to the osteomeatal unit was done.
Using LM system, the findings were scored from 0 to 24 based on the opacification of sinuses and blockage of the osteomeatal complex (OMC). The SN CT scan staging scored each sinus (maxillary, frontal, ethmoids and sphenoid) in a stage of I to IV with points 0, 1, 2 and 3. Left and right sides were staged separately and the total scores ranged from 0 to 30 [10].
Osteomeatal complex (OMC) is a vital area of sinus drainage and pathology at this site can lead to involvement of multiple sinuses. Hence the author has considered the disease at the OMC on CT scan separately [10]. OMC pathology was evaluated and based on the score and involvement of osteomeatal complex, CRS was categorized into category A (mild to moderate disease) and B (moderately severe to severe disease).
The data collected were tabulated in excel sheet and the correlation of SNOT 22 score with LM score and SN CT score were assessed. SNOT 22 score and LM score were considered as discrete variables and the correlation was assessed using Pearson product moment correlation. Both SNOT 22 and SN CT scores were considered as categorical variables and the correlation was assessed using Chi-Square Test. P value of < 0.05 was considered as significant.
Results
Our study included 150 patients. 90(60%) were males 60(40%) were females. The age ranged from 18 to 80 years with mean age of 40.01 (SD: 14.96).
The SNOT 22 score in the study ranged from 8 to 71, with a mean score of 30.62 (SD: 11.72). Mild disease included 33(22%), moderate 107(71.33%) and severe 10(6.66%) patients.
On evaluation of the CT scan using Lund Mackay Scoring system, the values were from 1 to 24 with a mean of 9.593 (SD: 5.902) with mean LM score of male patients was 9.61 (SD: 5.68) and female patients was 9.57 (SD: 6.27) and the difference between the mean scores of males and females was not statistically significant.
SN CT scan score ranged from 2 to 25 on evaluation of the CT scans. Based on total score and presence of OMC block, the patients were categorized in to Category A and B. As per disease severity 61 (40.7%) patients were in category A and 89 (59.3%) patients were in category B (Table 1). Out of 61 patients in category A, 34(55.7%) were males and 27(44.3%) were females. Males were 56(62.9%) and females were 33(37.08%) among the total of 89 patients in category B.
Table 1.
Modified CT scan scoring system (sn score) with criteria for symptom severity by the CT scan scores [10]. (a) Objective CT scan scoring. (b) Subjective severity grading
| (a) | ||
|---|---|---|
| Stage | Findings on CT scan | Points |
| I | No opacity | 0 |
| II | Mucosal thickening and opacity less than 25% of sinus | 1 |
| III | Mucosal thickening and opacity more than 25% and less than 50% of sinus | 2 |
| IV | Mucosal thickening and opacity more than 50% of sinus | 3 |
| (b) | |
|---|---|
| Group A (Mild-Moderate) (Mild and moderate symptoms present but not interfering with work or daily routine) |
Group B (Moderately severe-severe) (Moderately severe and severe symptoms present interfering with daily routine or sleep) |
|
Score of < 5 for unilateral < 8 for bilateral disease (Without Stage IV in any sinus) |
Score of > 5 for unilateral, > 8 for bilateral disease OR Stage IV in any sinus OR Pathology/block at OMC |
The correlation of LM score with SNOT 22 score was assessed by plotting Scattered plot diagram, which showed a moderate positive, statistically significant correlation (Pearson correlation co-efficient: 0.466; p value: 0.032) (Fig. 1).
Fig. 1.
SNOT 22 and LM score
The correlation of SN CT score with SNOT 22 was assessed by Chi Square test, which showed a highly significant positive correlation (p value of 0.000793) (Table 2).
Table 2.
SNOT 22 and modified CT score
| SNOT 22 grading | Mod CT grading | |
|---|---|---|
| A | B | |
| I | 23 (14.23) [5.40] | 12 (20.77) [3.70] |
| II | 37 (42.70) [0.76] | 68 (62.30) [0.52] |
| III |
1 (4.07) [2.31] |
9 (5.93) [1.59] |
| Each cell: observed value (Expected value) [Chi square value] | ||
Discussion
Chronic Rhino Sinusitis (CRS) is characterized by extreme variations in its presentation. A mere evaluation of symptoms may not be sufficient for the exact diagnosis of the disease. Documented findings suggestive of sino-nasal inflammation in nasal endoscopy and CT scan imaging help the surgeon for proper diagnosis and further management of the disease [2].
Various subjective as well as objective tools are being used for evaluation of the severity of CRS. Subjective tools are mainly based on disease-specific symptoms and quality of life of the patient. It includes TFR (Task Force on Sinusitis) guidelines, Rhino Sinusitis Disability Index (RSDI), Chronic Sinusitis Survey (CSS), Sino-Nasal Outcome Tests (SNOT) etc. Out of these, SNOT 22 is considered to be the most sensitive and disease-specific patient-reported outcome measure for assessing the disease severity [3, 4]. Objective tools include endoscopic, radiologic and surgical scoring systems. The scoring system introduced by Lund and MacKay (LM system) is the most widely used radiologic system for severity assessment. This system has been recommended by American Academy of Otolaryngology Task Force for evaluation the disease and for future researches [5, 12].
SNOT 22, a 22-point questionnaire is a validated symptom analysis tool for CRS. It analyses different aspects of disease outcome such as physical problem, functional limitations, and emotional consequences [13]. The mean SNOT 22 in our study was 30.62 (SD: 11.72). In our study, majority of the patients were under moderate category.
CT scan is the investigation of choice in CRS. It helps the surgeon to document the extent of sino-nasal inflammation and to plan the treatment. LM CT scan scoring system is widely used for assessment of severity of the disease which assesses the disease in qualitative way by scoring as per the mucosal opacification [14].
Our study has a mean LM score of 9.59 (SD: 5.90) with values ranging from 1 to 24. Osteomeatal Complex (OMC) is a vital area of sinus drainage and the block in this area provides a major contribution to the pathogenesis of CRS. LM scoring evaluates CRS quantitatively but doesn’t grade the severity. So, a patient with unilateral maxillary sinusitis will have a LM score of 2 but can have a severe disease. Hence the LM score lacks in severity grading which would serve as a useful prognostic tool and help in better management of the disease.
SN CT scan scoring system analyses the sino-nasal inflammation both qualitatively and quantitatively. The initial scoring is quantitative similar to LM scoring. However, it has a second part which grades the disease severity qualitatively [10].
Severity assessment using both subjective and objective tools can provide good and effective means of confirmation of the disease, prioritizing the treatment and assessing the effectiveness of treatment. The main disadvantage is that, both subjective and objective tools assess different aspects of the disease. Subjective tools analyze the symptoms and quality of life of the patient which show large inter patient variation and influenced by various non-disease specific factors. Objective tools assess the anatomical changes and pathology of the disease. This explains the poor correlation between subjective and objective scoring systems in literature [6–9]. Presence of an objective tool correlating well with symptoms, is much helpful for the surgeon for proper management of the disease.
Correlation between subjective and objective systems has been studied multiple times in the literature with few studies failed to find a correlation between these systems [6–9] and some other studies which used latest tools for severity assessment, found a correlation [15]. The probable explanation for the failure is, both systems approaches different aspects of the disease. Objective systems like LM system mainly assess the pathological aspect of the disease.
Our study shows a positive correlation of symptoms assessed by SNOT 22 system with radiological findings analyzed by both LM system as well as SN CT scan scoring system. However, SN CT scan scoring system showed a highly significant positive correlation over LM system as it correlates well with symptoms and also provides a grading of disease severity. The modified CT scan scoring system differs from other radiologic systems as it analyzes the disease both in qualitative and quantitative way and gives more importance to the pathology that imparts more effect on development of symptoms.
The advantages of SN CT scan scoring is that it can correlate well with symptoms and also can be used to objectively assesses the disease severity, with less inter observer variability and can be used in difficult to assess population (pediatric population, mentally challenged patients, non-cooperative patients etc.). SN CT scan scoring system hence serves as a documented, objective tool with high degree of repeatability.
Conclusion
SN CT scan scoring system can be considered as a tool for assessing the disease severity both in subjective and objective way. It can be used in place of subjective tools like SNOT 22 for assessing the severity of symptoms in CRS where subjective analysis of the disease is difficult. SN CT scan scoring system has to be further validated using large population studies at multi institutional level and incorporating different populations. Comparison of the strength of correlation of CRS symptoms with SN CT score and other radiological tools like LM score is scope of future researches.
Authors Contributions
Satish Nair: Substantial contributions to the conception or design of the work, revising it critically for important intellectual content, analysis and interpretation of data for the work and drafting the work and final approval of the version to be published. Brijith KVR: Substantial contributions to the acquisition of data for the work, revising it critically for important intellectual content and final approval of the version to be published. Aishwarya J G, Ashish S Shah: Substantial contributions to the acquisition of data, and drafting the manuscript.
Funding
Nil.
Compliance with Ethical Standards
Conflict of interest
The authors declare that they have no conflict of interest.
Footnotes
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
References
- 1.Fokkens W, Lund VJ, Hopkins C, et al. European position paper on rhinosinusitis and nasal polyps 2020. Rhinology. 2020;29:1–464. doi: 10.4193/Rhin20.600. [DOI] [PubMed] [Google Scholar]
- 2.Meltzer EO, Hamilos DL, Hadley JA, Lanza DC, Marple BF, Nicklas RA, et al. Rhinosinusitis: establishing definitions for clinical research and patient care. J Allergy Clin Immunol. 2004;114(6):155–212. doi: 10.1016/j.jaci.2004.09.029. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Morley A, Sharp H. A review of sinonasal outcome scoring systems—which is best? Clin Otolaryngol. 2006;31(2):103–109. doi: 10.1111/j.1749-4486.2006.01155.x. [DOI] [PubMed] [Google Scholar]
- 4.Rudmik L, Hopkins C, Peters A, Smith TL, Schlosser RJ, Soler ZM. Patient-reported outcome measures for adult chronic rhinosinusitis: a systematic review and quality assessment. J Allergy Clin Immunol. 2015;136(6):1532–1540.e2. doi: 10.1016/j.jaci.2015.10.012. [DOI] [PubMed] [Google Scholar]
- 5.Lund V, Kennedy D. Staging for rhinosinusitis. Otolaryngol Head Neck Surg. 1997;117(3):35–40. doi: 10.1016/S0194-5998(97)70005-6. [DOI] [PubMed] [Google Scholar]
- 6.Wabnitz DA, Nair S, Wormald P. Correlation between preoperative symptom scores, quality-of-life questionnaires, and staging with computed tomography in patients with chronic rhinosinusitis. Am J Rhinol. 2005;19(1):91–96. doi: 10.1177/194589240501900116. [DOI] [PubMed] [Google Scholar]
- 7.Bhattacharyya T, Piccirillo J, Wippold FJ. Relationship between patient-based descriptions of sinusitis and paranasal sinus computed tomographic findings. Arch Otolaryngol Head Neck Surg. 1997;123(11):1189–92. doi: 10.1001/archotol.1997.01900110039006. [DOI] [PubMed] [Google Scholar]
- 8.Hopkins C, Browne JP, Slack R, Lund V, Brown P. The Lund-Mackay staging system for chronic rhinosinusitis: How is it used and what does it predict? Otolaryngol Head Neck Surg. 2007;137(4):555–561. doi: 10.1016/j.otohns.2007.02.004. [DOI] [PubMed] [Google Scholar]
- 9.Basu S, Georgalas C, Kumar BN, Desai S. Correlation between symptoms and radiological findings in patients with chronic rhinosinusitis: an evaluation study using the sinonasal assessment questionnaire and Lund-Mackay grading system. Eur Arch of Oto-Rhino-Laryngol. 2005;262(9):751–4. doi: 10.1007/s00405-004-0891-0. [DOI] [PubMed] [Google Scholar]
- 10.Nair S. Correlation between symptoms and radiological findings in patients of chronic rhinosinusitis: a modified radiological typing system. Rhinology. 2009;47:181–186. [PubMed] [Google Scholar]
- 11.Toma S, Hopkins C. Stratification of SNOT-22 scores into mild, moderate or severe and relationship with other subjective instruments. Rhinol J. 2016;54(2):129–123. doi: 10.4193/Rhino15.072. [DOI] [PubMed] [Google Scholar]
- 12.Rosenfeld R, Piccirillo J, Chandrasekhar S, et al. Clinical practice guideline (Update) Am Acad Otolaryngol Head Neck Surg. 2015;152(4):598–609. doi: 10.1177/0194599815574247. [DOI] [PubMed] [Google Scholar]
- 13.Hopkins C, Gillett S, Slack R, Lund V, Browne J. Psychometric validity of the 22-item sinonasal outcome test. Clin Otolaryngol. 2009;34(5):447–454. doi: 10.1111/j.1749-4486.2009.01995.x. [DOI] [PubMed] [Google Scholar]
- 14.Lund VJ, Mackay IS. Staging in rhinosinusitis. Rhinology. 1993;31(4):183–184. [PubMed] [Google Scholar]
- 15.Brooks SG, Trope M, Blasetti M, et al. Preoperative Lund-Mackay computed tomography score is associated with preoperative symptom severity and predicts quality-of-life outcome trajectories after sinus surgery. Int Forum Allergy Rhinol. 2018;8(6):668–75. doi: 10.1002/alr.22109. [DOI] [PMC free article] [PubMed] [Google Scholar]