Diagnostic Evaluation of Chronic Nasal Obstruction Based on Nasal Endoscopy and CT Scan Paranasal Sinus

Abstract

Evaluation of the accuracy of objective diagnostic modalities for nasal obstruction and their comparison to each other to reach the correct diagnosis with minimum cost and highest accuracy. This study was conducted in the Department of Otorhinolaryngology and Head Neck Surgery, Chirayu Medical College and Hospital, Bhopal from August 2016 to September 2017. A total of 50 patients from age group 1–70 years irrespective of sex with complaints of chronic nasal obstruction, which were unresponsive to routine appropriate medical therapy, were selected for this study. Comparative study among findings of nasal endoscopy and CT scan of the paranasal sinuses done. After clinical examination, patients were subjected to high resolution computed tomography (HRCT) of paranasal sinuses and diagnostic nasal endoscopy (DNE). The diagnostic results of both modalities were compared. The most common symptoms were nasal obstruction and nasal discharge 100%, followed by post nasal drip 62%. The complaints related to eye and ears were less frequent, found in 4% only. CRS (Chronic Rhinosinusitis) was most common pathology of nose for nasal obstruction which is in 72% cases. Sinonasal polyp is present in 20% of cases. Inverted papilloma in 4% cases. Granulomatous disease (Rhinosporidiosis) in 2% cases. Malignancy in 2% cases. In this series of 50 cases, nasal endoscopy revealed various pathological abnormalities mainly in the osteomeatal area. These include mucopurulent discharge in middle meatus seen in 100% of cases (50 patients). This could not be revealed in HRCT. Oedematous and polypoid infundibular mucosa/polyp in nasal cavity in 28% cases (14 patients) where it was not diagnosed in HRCT in three patients. Hence DNE proved superior to HRCT. Other abnormalities detected on nasal endoscopy were septal deviation 80% of cases (40 patients), inferior turbinate hypertrophy 66% of cases (33 patients), middle turbinate hypertrophy/concha bullosa in 48% of cases (24 patients). DNS was diagnosed in 42 patients in HRCT other causes of nasal obstruction such as Agar nasi cell is detected in 16% (8 patients), medialised uncinate process in 16% (8 patients), paradoxical MT in 30% cases were diagnosed more accurately in nasal endoscopy than HRCT. So nasal endoscopy proved better than CT scan. Nasal obstruction is the most common presenting complaint in day to day otolaryngology practice. Nobody would disagree with the role of CT scan and diagnostic nasal endoscopy in diagnosing the nasal and paranasal pathologies. But as a treating physician we are always concerned about early diagnosis and cost effectiveness. At the same time we also have to consider about patient waiting and work load. In this study we attempted to find out whether diagnostic nasal endoscopy can be better then CT scan, so that we can treat our patient appropriately. Though there has been an increased demand for imaging the paranasal sinuses with coronal CT because of functional endoscopic sinus surgery, nasal endoscopy is a better option in diagnosing and assessing the extent of disease and anatomy.

Introduction

Nasal obstruction represents one of the most common patient’s complaint in day to day otolaryngology practice. The list of possible diagnosis is long. To come to a definitive diagnosis the patient has to undergo the series of investigations. The existing literature has already emphasized the role of CT scan and diagnostic nasal endoscopy. The problem can be self-limited or constant, a stand-alone concern or part of an array of symptoms [1, 2].

There has been an increased demand for imaging the paranasal sinuses with coronal CT because of functional endoscopic sinus surgery where a road map of the sinus anatomy and extent of disease is an essential pre-operative investigation [3].

Sinonasal endoscopy is mentioned as a standard test to precisely assess nasal obstructive disease and it is considered necessary in all patients with nasal obstruction, especially after the second week of evolution [4]. Computed tomography scan (CT) of the nose and paranasal sinuses is the ideal imaging exam (gold standard) to study nasal and paranasal sinuses diseases. It has high sensitivity because it provides precise information about soft and bone parts of the nasal cavity, Paranasal sinuses, orbit and endocranium.

Aims and Objective

1. Evaluation of the accuracy of objective diagnostic modalities for nasal obstruction and their comparison to each other to reach the correct diagnosis with minimum cost and highest accuracy.

2. Comparative study among findings of nasal endoscopy and CT scan of the paranasal sinuses, in chronic nasal obstruction, individualizing the importance of each exam for a conclusive diagnosis.

Materials and Methods

This prospective diagnostic cohort study was conducted in the department of Otorhinolaryngology and Head Neck Surgery, Chirayu Medical College and Hospital, Bhopal from August 2016 to September 2017. A total of 50 patients from age group 1–70 years irrespective of sex with complaints of chronic nasal obstruction, which were unresponsive to routine appropriate medical therapy, were selected for this study.

All patients with the chronic nasal obstruction were subjected to detailed clinical examination, and ENT examination, complete blood count, diagnostic nasal endoscopy and CT scan PNS coronal section. Comparative study among findings of nasal endoscopy and CT scan of the paranasal sinuses done. Kappa value (K) calculated for degree of agreement (poor agreement < 0.20, fair agreement 0.020–0.40, moderate 0.40–0.60, good 0.60–0.80, very good 0.80–1.00).

Observation

After clinical diagnosis, these patients were subjected to high resolution computed tomography (HRCT) of paranasal sinuses and diagnostic nasal endoscopy (DNE). The diagnostic results of both modalities were compared (Tables 1, 2 and Fig. 1).

Table 1.

In the present study, all the patients presented with following symptoms (n = 50)

Symptoms	No. of cases	Percentage
Nasal obstruction	50	100
Nasal discharge	50	100
Nasal mass	14	28
Disorders of olfaction	17	34
Headache	17	34
Sneezing	16	32
Epistaxis	6	12
Postnasal drip	31	62
Eyes-watering, itching, proptosis	4	8
Ear related problems	4	8

Table 2.

Classification of cases on the basis of nasal pathologies (n = 50)

Nasal pathology	No. of cases	Percentage
Rhinosinusitis	36	72
Sinonasal polyp	10	20
Inverted papilloma	2	4
Granulomatous (Rhinosporidiosis)	1	3
Malignancy (Sq. cell carcinoma)	1	2
Total	50	100

Fig. 1.

Nasal pathology

Nasal obstruction and nasal discharge were the most common symptoms seen in all 50 cases (100%) followed by post nasal drip 62%. CRS is most common pathology of nose for nasal obstruction which was seen in 72% cases. Sinonasal polyp was present in 20% of cases. Inverted papilloma in 4% cases. Granulomatous disease (Rhinosporidiosis) in 2% cases. And malignancy in 2% cases.

In this series of 50 cases, nasal endoscopy revealed various pathological abnormalities mainly in the osteomeatal area. Mucopurulent discharge in middle meatus seen in 100% of cases (50 patients), this could not be revealed in HRCT. Oedematous and polypoid infundibular mucosa/polyp in nasal cavity in 28% cases (14 patients) which was missed in HRCT in 3 patients. Hence DNE proved superior to HRCT (Table 3, Fig. 2).

Table 3.

Comparison between CT Scan and nasal endoscopic finding (n = 50)

Findings	Total no cases
	Nasal endoscopy	Percentage	CT scan	Percentage	Kappa value (K)
Septal deviation	40	80	42	84	0.86
ITH	33	66	30	60	0.87
Medialised UP	8	16	6	12	0.83
Paradoxical MT	15	30	8	16	0.61
MTH or CB	24	48	22	44	0.92
Large bulla ethmoidalis	5	10	6	12	0.90
Agar nasi cell	8	16	7	14	0.92
OMC block/meatal stenosis	26	52	30	60	0.84
Oedematous and polypoidal infundibular mucosa/polyp in nasal cavity	14	28	11	22	0.84

Fig. 2.

Comparison between CT PNS and diagnostic nasal endoscopy

Other abnormalities detected on nasal endoscopy were septal deviation 80% of cases (40 patients), inferior turbinate hypertrophy 66% of cases (33 patients), middle turbinate hypertrophy/concha bullosa in 48% of cases (24 patients). DNS was diagnosed in 42 patients in HRCT.

Other causes of nasal obstruction such as Agar nasi cell is detected in 16% (eight patient), medialised uncinate process in 16% (eight patients), paradoxical MT in 30% cases were diagnosed more accurately in nasal endoscopy than HRCT. So nasal endoscopy proved better than CT scan.

CT scan paranasal sinus shows better view for posterior part of septum and is better for septal deviation in this study, 84%, enlarge ethmoid bulla, 12% and osteomeatal block 52%. Hence CT scan could diagnose high septal deviations and osteomeatal blockage better than nasal endoscopy.

In case of nasal mass, there was no significant difference. But CT scan can be useful in diagnosing bony dehiscence or extent of the disease in surrounding structures.

Discussion

A blocked nose represents one of the most common patient complaints in day to day otolaryngology practice [1]. The list of possible diagnosis is long. To come to a definitive diagnosis the patient has to undergo the series of investigations. In today’s consumer’s era, due to patient’s awareness one has to come to early definitive diagnosis with cost effectiveness. The existing literature has already emphasized the role of CT scan and diagnostic nasal endoscopy in early and definitive diagnosis [5].

According to Y.K. Maru and Y. Gupta diagnostic nasal endoscopy proved a better technique to detect various sinonasal pathologies as well as anatomical variations, which are otherwise missed on Computed Tomography or inaccessible on anterior rhinoscopy especially in the key area comprising the ostiomeatal complex. They emphasised nasal endoscopy as an essential part of a complete examination of the nose and sinuses. Lohiya et al. in their studies found no significant difference in diagnosing CRS by either modality. According to them, the addition of nasal endoscopy helps reduce the use of CT, reducing costs and radiation exposure. But this study was limited only to chronic rhino sinusitis. AF Duarte et al. in their study concluded that the results of nasal fossa findings obtained by nasal endoscopy were more conclusive in the elucidation of diagnosis than those obtained by computer tomography of the paranasal sinus [6, 7].

In our study we found that paradoxical middle turbinate, early nasal polyp, turbinate hypertrophy was better diagnosed on nasal endoscopy. Whereas due to severe DNS where scope could not be negotiated CT scan proved to be a useful tool for elucidation of pathology and anatomy.

Endoscopy allows an exceptionally clear and well illuminated field with the added advantage of the ability to inspect the recess with angled distal lenses. It helps in diagnosis of sinonasal pathology by revealing structural details and anatomical variations in the nasal cavity to a greater extent. It allows accurate definition of the extent of lesion and early diagnosis of recurrence is also possible. Nasal endoscopy allows the identification of areas of inflammation in the nasal cavity [8].

There are certain limitations of nasal endoscopy which includes inability to look for disease in patients with deviated nasal septum, constricted middle meatus and presence of hidden air spaces like sphenoid sinus, ethmoid bulla and posterior ethmoids. Endoscopy is an office procedure done under local anaesthesia hence it help in quick assessment and early diagnosis with no radiation exposer and minimal cost.

Coronal CT scan accurately defines microanatomical locales in and around the Osteomeatal Unit, and also identifies dangerous anatomical variants like dehiscent optic nerve, Canal and carotid artery canal. Thus it seems to be a valuable guide to the surgeon in the planning operative procedure, avoiding intraoperative complications and assessing surgical programmes and the success rate of procedure.

Endoscopically, concha bullosa appears as an enlarged head of middle turbinate. Concha bullosa are best diagnosed radiographically by CT scan PNS coronal section which enables visualization of even very small pneumatization, so CT scan is better here.

Kappa value (K) shows correlation between endoscopy and CT Scan PNS in our study both modalities has very good and good correlation. In study of Sheetal et al. the concha bullosa didn’t show good correlation (K = 59.7%), the uncinate process attachment showed excellent correlation (K = 84.97) [9].

CT-scans cannot differentiate between obstructive sinusitis and tumour extension without sinus bone destruction, so biopsy has proven to be the most reliable way of differentiating between early stage PNS cancer without bone destruction and chronic sinusitis. The critical role of endoscopic techniques for diagnosis, biopsy and follow-up of nasal, paranasal sinus and skull base tumours is well-recognised. Endoscopic surgery has become the first line therapy for the removal of many benign tumours, as with inverted papillomas.

CT is an expensive investigation and the study would not have remained cost effective as compare to nasal endoscopy. Combination of CT scan PNS and fiber optic diagnostic nasal endoscopy is excellent for precise evaluation of nasal cavity. Coronal CT scan provides a road map to accurately define the microanatomy of the nose and paranasal sinuses.

Conclusion

Nasal endoscopy and CT scan are complimentary in the assessment of various anatomical variations in the ostiomeatal complex and in intrasinus mucosal disease. Combination of CT scan PNS and fiber optic diagnostic nasal endoscopy is excellent for precise evaluation of nose and paranasal sinuses. CT scan is mandatory as a pre operative work up in patients who have to undergo FESS; as it provides a map on by the help of which to the operation can be done. But where we want avoid exposure to radiations, and excessive costs, nasal endoscopy appears to be a valuable diagnostic tool for not only assessing the pathology, but anatomy also. As nasal endoscopy is done by the surgeon himself, the diagnosis and assement is quick rather than waiting for CT scan appointment and reporting. Ct scan can be reserved for the cases where endoscope cannot be negotiated due to severe DNS or other factors. Though there has been an increased demand for imaging the paranasal sinuses with coronal CT because of functional endoscopic sinus surgery (FESS), nasal endoscopy is a better option in diagnosing and assessing the extent of disease and anatomy.

Compliance with Ethical Standards

Conflict of interest

All authors declare that they have no conflict of interest.

Ethical Standards

Ethical approval taken from institution.