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 Table of Contents  
ORIGINAL ARTICLE
Year : 2020  |  Volume : 32  |  Issue : 2  |  Page : 107-114

Efficacy of ultrasound in the diagnosis of swellings of orofacial region: An original research


1 Department of Oral Medicine and Radiology, Yashoda Hospital and Research Centre, Nehru Nagar, Ghaziabad, Uttar Pradesh, India
2 Department of Oral Medicine and Radiology, Primary Health Centre, Khaira, Jamui, Bihar, India
3 Department of Public Health Dentistry, Dr. B.R. Ambedkar Institute of Dental Sciences and Hospital, Patna, Bihar, India
4 Department of Conservative Dentistry and Endodontics, ITS Dental College, Hospital and Research Centre, Greater Noida, Uttar Pradesh, India
5 Department of Oral Medicine and Radiology, Institute of Dental Sciences, Bareilly, Uttar Pradesh, India
6 Department of Oral and Maxillofacial Surgery, Sarjug Dental College and Hospital, Darbhanga, Bihar, India

Date of Submission10-Mar-2020
Date of Decision06-May-2020
Date of Acceptance14-May-2020
Date of Web Publication27-Jun-2020

Correspondence Address:
Dr. Mallika Kishore
Department of Oral Medicine and Radiology, Yashoda Hospital and Research Centre, Nehru Nagar, Ghaziabad, Uttar Pradesh
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jiaomr.jiaomr_39_20

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   Abstract 


Introduction: Accurate diagnosis of a head and neck swelling is of paramount importance. Various disease processes may affect head and neck regions which present clinically as swellings. Aims and Objectives: This study aimed to evaluate the efficacy of ultrasonography (USG) in the diagnosis of swellings of the head and neck regions. The objectives of this study were to assess the reliability of USG in differentiating various swellings of head and neck region and to correlate between diagnosis of swellings by clinical, histopathological, and by USG. Materials and Methods: A total of 70 patients with an age range of 15–70 years and clinically obvious swellings in the head and neck region were included. After clinical examination, all the seventy patients were subjected to ultrasonographic investigation. Features like shape, boundary, echo intensity, presence of necrosis and calcifications, and posterior echoes were considered in describing the ultrasonographic images of swellings. Following clinical and ultrasonographic diagnosis, surgical intervention was carried out. The obtained biopsy specimens were submitted for histopathological examination and a final diagnosis was made. Statistical Analysis: The collected data were subsequently processed and analyzed using the SPSS statistical package version 17. Results: The diagnostic accuracy of ultrasound was found to be 98% in the diagnosis of cystic lesions, 98.47% in benign tumors, 98.57% in malignant tumors, 100% in lymphadenopathies, and in muscle origin and 94.29% in space infections and abscesses. Conclusion: It can be concluded that, together with clinical and histopathological examinations, USG works out as a valuable adjunct in the diagnosis of orofacial swellings.

Keywords: Cysts, orofacial region, swellings, ultrasound


How to cite this article:
Kishore M, Alok A, Singh S, Kishore A, Panat SR, Sah VK. Efficacy of ultrasound in the diagnosis of swellings of orofacial region: An original research. J Indian Acad Oral Med Radiol 2020;32:107-14

How to cite this URL:
Kishore M, Alok A, Singh S, Kishore A, Panat SR, Sah VK. Efficacy of ultrasound in the diagnosis of swellings of orofacial region: An original research. J Indian Acad Oral Med Radiol [serial online] 2020 [cited 2020 Nov 24];32:107-14. Available from: https://www.jiaomr.in/text.asp?2020/32/2/107/288137




   Introduction Top


The maxillofacial region is a common anatomic site for the development of infections, cysts, and tumors of odontogenic or nonodontogenic origin. Because of the wide variation of the lesions manifesting in this region, diagnosis becomes a complex process.[1] Various disease processes may affect the head and neck regions, which present clinically as swellings.[2] Swellings can arise from virtually any structure in the cervicofacial region. World Health Organization (WHO) has broadly categorized them as follows: benign and malignant tumors, hamartomas and vascular malformations, cysts, and inflammatory swellings.[3] Some of the most common soft-tissue alterations of the head and neck region are inflammatory swellings such as space infections of the odontogenic in origin, diseases of salivary glands, and lymph node reactions.[4] But in some cases, such as chronic inflammation, abscess formation, deep-seated or infected cystic lesion, and neoplasms, clinical examination and palpation do not provide a complete assessment of the exact origin and nature of swellings; such cases require radiological imaging. Therefore, to get a final diagnosis, a clinical examination must be joined with various investigative procedures. In recent times, modern imaging techniques like digital radiography, computed tomography (CT), magnetic resonance imaging (MRI) and nuclear medicine methods such as positron emission tomography have made an immense contribution in the diagnosis of intra-osseous and extra-osseous swellings in the orofacial region. But the limitation is that these are very expensive and are not available universally with very high exposure.[5] An alternative diagnostic tool that is widely available, relatively inexpensive, and noninvasive is ultrasonography (USG).[6]

Many obstructive, inflammatory, and tumourous lesions can be detected and differentiated by ultrasound.[7] USG can provide accurate information on the content of intraosseous lesions of the jaws before any surgical procedure.[8] It helps delineate the presence of multiple lymph nodes and the course of resolution of infectious diseases. It is used to visualize the presence and extent of facial abscesses. It can be used in cases of oral carcinoma to observe the presence of regional lymph node metastasis.[9] High-resolution ultrasound is also a reliable tool in evaluating tumor thickness and clearance of surgical margins of the tumor.[10] Very few studies have been carried out in this regard. Hence this study was carried out to determine the accuracy, sensitivity, specificity, and prediction values of ultrasound as a means of diagnosis of the swellings.


   Materials and Methods Top


This study was conducted in the department of Oral Medicine and Radiology. The inclusion criteria of the study were all patients with an age range of 15–70 years with clinically obvious swellings in the head and neck regions [Figure 1]. The exclusion criteria of the study were patients who were having swelling owing to trauma or fractures. Patients having an odontogenic cyst and tumor were not included in the study. A biopsy of swellings was done and histopathological examination of the specimen was carried out. The ultrasonographic evaluation was done at the department of General Radiology of the medical college by the same single radiologists every time. The patient's detailed case history was recorded and clinical examination of swellings was carried out based on criteria given by Kerr Ash Millard. After explaining the procedure, the purpose of the study, informed consent was taken from each and every patient. After the provisional diagnosis, patients were subjected to radiographic examinations wherever required, which included periapical radiographs, orthopantomogram (OPG), and then the ultrasonographic examination of the swelling was done. Ultrasound was carried out using a diagnostic ultrasound system Toshiba Power vision with linear probe 5-11 MHz, TVS probe 7.5 MHz. The diagnosis of all cases were further confirmed by histopathological examination. Based on clinical diagnosis, swellings were divided into groups: (1) inflammatory swellings, (2) cystic swellings, (3) benign swellings, (4) malignant swellings, (5) lymph node swellings, and (6) muscle origin. An ultrasound examination was then performed in the department of radiology, using the diagnostic ultrasound machine. The contents of the lesion were assessed on the USG imaging using the density values as given by the computer. The images of each lesion were analyzed by the same expert radiologist every time, based on the echogenecity to describe the appearance of bone pathogenesis. The images were assessed for the size and content (fluids, solid, or combination of both). The following features were considered in describing the USG images of swelling in the head and neck per Shimizu et al.[11]
Figure 1: Extraoral swelling in the right mandibular region

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  1. Shape: oval, lobular, round, polygonal, irregular
  2. Boundary: very clear, relatively clear, partially unclear, ill-defined
  3. Echo intensity: anechoic, isoechoic, hypoechoic, hyperechoic, mixed
  4. Ultrasound architecture of lesion: homogeneous, heterogeneous
  5. Presence of necrosis: eccentric, central
  6. Presence of calcification: macrocalcification, microcalcification;
  7. Posterior echoes: enhanced, unchanged, attenuated; and
  8. ultrasound characteristic of tissues: cystic, solid, mixed.


Following clinical and USG diagnosis, surgical intervention was carried out by incision and drainage or excision/incisional biopsy/fine-needle aspiration cytology as indicated. The obtained biopsy specimens were submitted for histopathological examination and a final diagnosis was made. The obtained results were tabulated and statistically analyzed. Student's t test was used. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the test were calculated to evaluate the reliability and diagnostic efficacy of USG as an investigative tool.


   Results Top


In a total of 70 subjects examined, the minimum age of the patient found in the study was 16 years and the maximum age was 70 years. The mean age was 38 years. Of 70 subjects, the study sample consisted of 33 (47.1%) females and 37 (52.9%) males. Of 70 patients with head and neck swellings, 34 (48.5%) were inflammatory swellings, 09 (12.9%) were benign neoplasms, 8 (11.4%) were cystic swellings, 7 (10%) swellings were of muscle origin, 5 (7.4%) were malignant neoplasms and 7 (10%) were lymph node origin [Table 1].
Table 1: Distribution of swellings according to histopathology

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Inflammatory swellings

Of 70 patients, 48.5% were inflammatory swellings, which showed signs of inflammation. They were either from the odontogenic origin (62%) or of nonodontogenic origin (38%). Among the odontogenic swellings there were seven cases of abscess, five cases of cellulitis, ten cases of fascial space infection. Nonodontogenic inflammatory swellings consisted of seven cases of submandibular sialadenitis and six cases of parotitis [Figure 2]. On USG, inflammatory swellings were irregular by shape (64%) with ill-defined borders (47%) and the echoes intensity was slightly hypoechoic (40.9%). The internal echoes were heterotrophic without characteristic (65.7%) and posterior echoes were unchanged in 74.2%. The clinical diagnosis had a sensitivity of 76.47% and specificity of 91.46% whereas USG had a sensitivity of 97.06% and specificity of 91.67% [Table 2]. The diagnostic accuracy of the clinical diagnosis was found to be 84.29% whereas the diagnostic accuracy of ultrasound was found to be 94.29% [Graph 1].
Figure 2: Ultrasonogram showing hypoechoic lesion suggestive of parotitis

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Table 2: Comparison of sensitivity, specificity of clinical and USG diagnosis

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Benign neoplasms

Benign neoplasms comprised 12.8%. Sonographically these lesions were oval (22.2%) to lobular in shape (11.1%), slightly hypoechoic (33.3%), with relatively clear borders (77.7%), internal density ranged from homogeneous (66.66%) to heterotrophic without characteristic (33.33%) and no changes were appreciated posterior to the lesion [Table 3]. The clinical diagnosis had sensitivity (77.78%) and specificity (98.36%), whereas ultrasound had a sensitivity (88.89%) and specificity of 100%. The diagnostic accuracy of the clinical diagnosis was found to be 95.71% whereas the diagnostic accuracy of the ultrasound was 98.57%.
Table 3: Comparison of different sonographic features in different sample groups

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Cystic swellings

11.4% of all the cases were cystic swellings, of which cyst of odontogenic origin formed 62.5% and nonodontogenic cysts formed 37.5%. USG of cystic lesions had very clear borders (100%), oval (37.5%), their internal echo density was anechoic (87.5%), homogeneous internal echo density was noted (87.5%) and all the lesions had posterior acoustic enhancement. Clinical and ultrasound diagnosis had a sensitivity of 87.5% whereas clinical diagnosis had a specificity of 93.55% and ultrasonographic diagnosis had 98.3% [Graph 2]. The diagnostic accuracy of clinical diagnosis was found to be 92.86% whereas the diagnostic accuracy of ultrasound was found to be 97.14%.



Muscle origin

Swellings of muscle origin comprised of 10% all patients. Sonographically all the swellings had relatively clear borders, polygonal in shape, had hypoechoic heterotrophic with characteristic internal echo density and posterior echoes were unchanged. The sonographic and clinical diagnosis of all cases conformed with the final diagnosis so the sensitivity and specificity of sonographic and clinical diagnosis was 100% in our study.

Lymph node origin

Seven were lymph node swellings (10%). They appeared as homogeneous (85.7%), hypoechoic (71.42%), oval (57.1%), with clear border (28.5%), and no change was noted in the posterior echo intensity. The clinical diagnosis had a sensitivity of 85.71% and specificity of 96.83% whereas sonographic diagnosis had sensitivity and specificity of 100% [Table 4]. The diagnostic accuracy of clinical diagnosis was found to be 95.71% whereas USG had a diagnostic accuracy of 100%.
Table 4: Ultrasonography versus histopathological diagnosis

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Malignant neoplasms

7.4% were malignant lesions of all the lesions studied, which sonographically had relatively clear borders (60%), had polygonal shape (60%), echo intensity was varying from slightly hypoechoic (40%) to hypoechoic (40%), internal density was multiple anechoic (20%) to heterotrophic without characteristic (40%) and no change was noted posteriorly. The clinical diagnosis had a sensitivity of 40% and specificity of 98.46% [Graph 3]. The sonographic diagnosis had a sensitivity of 80% and specificity of 100%. The diagnostic accuracy of the clinical diagnosis was found to be 94.29% whereas diagnostic efficacy of ultrasound was found to be 98.57%.



Overall clinical versus (v/s) histopathological diagnosis contingency coefficient was 0.868 [Table 5]. Various groups of swellings have their unique sonographic characteristics [Table 6].
Table 5: Contingency coefficients (P) of ultra-sonographic architecture of lesions

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Table 6: Various groups of swellings with their unique sonographic characteristics

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   Discussion Top


USG is a safe reliable method of examination that causes little patient discomfort and is a well-established noninvasive imaging procedure for soft-tissue masses such as in the maxillofacial region.[12] USG can provide accurate information on the content of intraosseous lesions of the jaws before any surgical procedure.[13]

Of 70 cases in our study, eight were cystic swellings. This included five radicular cysts and three sebaceous cysts. In two of the eight cases clinical diagnosis did not match with final diagnosis and in one case sonographic diagnosis did not match with the final diagnosis. One case which was diagnosed as cyst clinically and histopathologically while was found to be an abscess on ultrasound examination. One case which appeared to be an abscess on clinical examination was found to be cyst by USG and histopathology.

In this study, the clinical diagnosis of cystic swellings had a sensitivity of 87.5% and specificity of 93.55% whereas sonographic diagnosis had a sensitivity of 87.5% and specificity of 98.3% [Graph 4]. The results of our study were in accordance with the study conducted by Chandak et al. and Shivanand et al. who reported specificity of 98.3%.[14] The diagnostic accuracy of ultrasound in this study was found to be 98% which was in accordance with a study conducted by Chandak et al. 7 cases (10%) of masseteric hypertrophy were included in our study. In our study, all the volunteers had relatively clear borders (100%), and they appeared as homogeneous with a hypoechoic band (100%) with the transverse measurement of 15 mm-21 mm. The sonographic and clinical diagnoses of all cases are in conformity with the final diagnosis so the sensitivity and specificity of sonographic and clinical diagnosis was 100% in our study which is in accordance with the study conducted by Shanker et al.[15]



Nine (12.8%) were benign neoplasms which included five cases of lipoma, two cases of capillary haemangioma, and two cases of lymphangioma. Clinically seven were diagnosed as benign tumors, one as malignancy and one as cyst. Ultrasound was able to identify 8 benign tumors which included four cases of lipoma, two cases of haemangioma, two cases of lymphangioma. In this study, the clinical diagnosis had sensitivity (77.78%) which was in accordance with the study conducted by Shankar et al. and specificity (98.36%) whereas ultrasound had sensitivity of 88.89% and specificity of 100% which was in accordance with the study conducted by Shanker et al. The diagnostic accuracy of the ultrasound in diagnosing benign neoplasms in this study was 98.47% which was in contrast with the study conducted by Pallagatti et al. where the diagnostic accuracy of ultrasound was found to be 87.5%. The difference in the results could be due to morphological and histological types of tissues.

In this study among 34 inflammatory swellings 21 (61.8%) were of odontogenic origin and 13 (38.2%) were from nonodontogenic origin. In this study, the clinical diagnosis had a sensitivity of 76.47% and specificity of 91.46% whereas USG had sensitivity of 97.06% which in accordance with the study conducted by Chandak et al. and specificity of 91.67%. This finding was not in harmony with the study conducted by Shanker et al. The diagnostic accuracy of ultrasound in this study was found to be 94.29% which was slightly less than the finding found in a study conducted by Chandak et al. This slight variation was probably because of the less sample size in our study.

Of 90 cases with head and neck swellings, five were malignant neoplasms (7.4%). All the cases reported with rapidly growing swelling, which were diagnosed clinically as malignant lesions. Of 5 cases, 2 cases were well-differentiated squamous cell carcinoma, 2 were moderately differentiated squamous cell carcinoma, one was poorly differentiated squamous cell carcinoma.

In two cases of the five cases clinical diagnosis did not match with the final diagnosis. Two cases that appeared to be osteomyelitis on clinical examination were diagnosed as squamous cell carcinoma on ultrasound and histopathological examination. USG could identify 4 cases correctly, one case where ultrasound provided the wrong diagnosis, the lesion was small, and without the destruction of the cortex.

Seven cases (10%) of masseteric hypertrophy were included in our study. Masseter on sonogram appeared as homogeneous structure lying adjacent to the echogenic band of the mandible and the muscle width was measured both in the relaxed and contracted state by asking the patient to clench his teeth and the normal range for transverse dimension is 8.5-13.5 mm. In our study, all the volunteers had relatively clear borders (100%), and they appeared as homogeneous with hypoechoic band (100%) with the transverse measurement of 15 mm-21 mm. The sonographic and clinical diagnoses of all cases are in conformity with the final diagnosis so the sensitivity and specificity of sonographic and clinical diagnosis was 100% in our study.

Swellings of lymph node origin comprised of seven cases (10%). Comparing the clinical diagnosis with the final diagnosis one patient's clinical diagnosis did not match with the final diagnosis. One case which was clinically diagnosed as fascial space infection came to be lymphadenitis on ultrasound and histopathological examination. On comparison of final diagnosis with sonographic diagnosis, all the sonographic diagnosis was in agreement with the final diagnosis. In this study ultrasonographic diagnosis had a sensitivity and specificity of 100% which is in accordance with the studies by Shivanand et al.[13] In our study, the sensitivity and specificity of ultrasonographic diagnosis was 100% which could be attributed to bias in the sample selection, as we included only patients with the swelling or fullness in that region, which on sonogram was more than 10 mm, which were considered as malignant according to the previous studies by Yuasa et al.[16] Different lesions have different unique characteristics on the radiographic examination which helps the radiologists in the diagnosis of various swellings [Table 7].[17]
Table 7: Differentiating features of various lesions

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Although ultrasonographic pictures of various lesions were consistent and did correspond with a great degree of accuracy in all the groups of the lesions, it should only be used as an additional diagnostic tool rather than as the only investigative method in arriving at a final diagnosis. This study reviewed the usefulness of USG as a diagnostic tool in patients with cervicofacial swellings and found it very useful in differentiating solid and cystic swellings. The shape, size, frequency, and resolution of the probe and the experience of the sonologist will greatly enhance the accuracy of diagnosis.


   Conclusion Top


Most of the dentists are not aware of the utilities of USG for the diagnosis of various maxillofacial lesions. The results of this study illustrate the usefulness of diagnostic ultrasound imaging and support the use of the ultrasonographic method of imaging in the assessment of all maxillofacial swellings. From this study, it can be concluded that USG is highly reliable in diagnosing swellings of lymph node origin, followed by benign neoplasms, soft-tissue cystic swellings followed by inflammatory swellings of the head and neck region. It can be concluded from the study that, together with clinical and histopathological examinations, USG works out as a valuable adjunct in the diagnosis of orofacial swellings. However, there are certain drawbacks in this study owing to the small sample size. Therefore, further studies with a larger sample size, including a variety of swellings may contribute towards reinforcing the efficiency of diagnostic USG in the orofacial region.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Ethical considerations

Ethical clearance was taken from the institutional ethical committee of the institute.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7]



 

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