Introduction
Because of its broad availability, cheap cost, and absence of ionising radiation, ultrasonography is the imaging technique of choice for assessing thyroid nodules. Furthermore, because of its placement in the neck, the thyroid is easily accessible and susceptible to high-frequency sonographic assessment for precise characterisation.1 Thyroid nodules are rather frequent.2 Many more subclinical nodules are being found because to the widespread use of high-resolution ultrasonography. Palpation reveals them in 4% to 8% of adults, ultrasonography reveals them in 10% to 41%, and autopsy reveals them in up to 50%.3 Sonographic parameters such as composition, echogenicity, margins, direction, presence and kind of calcifications, vascularity, and extrathyroidal extension, if present, should all be considered while evaluating a thyroid nodule. The overall sonographic pattern, in combination with the size, indicates the likelihood of malignancy and allows the radiologist to give a treatment decision. 4, 5 If there are many nodules, each one should be characterised and treatment options made based on individual nodule suspicion, which may need several FNAs.6 Cystic or spongiform nodules, as well as numerous nodules (without worrisome traits) in an enlarged thyroid gland, are all signs of benignity. Hypoechogenicity, solid composition, uneven edges, taller-than-wide orientation, and microcalcifications are all related with malignancy, with the last three having the greatest specificities.7 The usual procedure for determining treatment regimens for thyroid nodules is fine-needle aspiration (FNA). The "benign" category, according to the Bethesda method, the most widely acknowledged approach for reporting thyroid cytology, denotes a risk of malignancy of less than 3%.8 When the nodule's cytologic finding is "benign," a follow-up ultrasonography (US) is indicated.9 When a nodule demonstrates considerable growth or morphologic alteration with "suspicious" US characteristics on follow-up, a repeat FNA is advised. 10, 11
Aim of the Study
To evaluate thyroid nodules by HRUSG and correalte its findings with fine needle aspiration cytology (FNAC).
Materials and Methods
Ethical institutional committee permission was taken. Written informed consent was obtained from the all the cases included in the study.
This is a prospective observational research that was undertaken at the department of Radiology, Maheshwara medical college and Hospital, Chitkul, near Isnapur, Patancheru, Sangareddy, Telangana from June 2018 to May 2021.
Methodology
After taking a properly informed written consent and complete history was taken including history of present illness, past history and personal history. Clinical examination was done and these cases were subjected to high resolution ultrasound neck. The diagnosis was confirmed by fine needle aspiration cytology (FNAC) findings.
Ultrasound technique
In supine posture with hyperextended neck resting on a pillow maintained under shoulder, USG Neck was done using a high-resolution ultrasonography (GE LOGIQ C5) equipped with a 5–12 MHz linear probe. The consistency, connection with the vasculature, and any other anomalies such as internal echoes, calcification, and so on were noted in transverse, longitudinal, various angled, and oblique orientations. Echogenicity, calcification, internal vascularity, cystic regions, lymphadenopathy, and background thyroid alterations were all considered while evaluating the nodules. The nodules were classed as hypoechoic when their echogenicity was lower than that of the thyroid gland, and hyperechoic when their echogenicity was higher than that of the background thyroid parenchyma. Microcalcification (for little calcification without shadowing and measuring less than 1mm) and macrocalcification (for larger calcification measuring more than 1mm) were used to classify the calcification (calcification with shadowing measuring more than 1mm, including coarse and curvilinear calcification). Internal vascularity was seen on Doppler, as well as cystic regions. When nodes were enlarged by more than 1 cm in their short axis or had microcalcification or cystic regions (regardless of size) and architectural distortion, lymphadenopathy was identified. The remainder of the thyroid's architecture was examined for adenomatous hyperplasia, colloid nodules, and Hashimoto's thyroiditis. When possible, the final ultrasonography diagnosis based on these features was compared to FNAC and histologic evaluation of the post-thyroidectomy samples.
FNAC was done on the cases presented with thyroid nodules. It was done with 10 cc disposable syringe under all aseptic measures. Aspirated material was stained with H & E and Pap stain and reported by senior pathologist in Pathology department.
Statistical analysis
Data will be entered in Microsoft Excel sheet and will be analysed using SPSS version 20.0 statistical software. Data will be depicted in the form of tables and braphs. Sensitivity, Specificity, Accuracy, Negative predictive value, Positive predictive value were calculated from the data.
Results & Observations
Age distribution varied from 20 years to 70 years. Majority of the cases were present between 41-50 years ie, 48.5% (39/80), 27.5% (22/80) constituted in 31-40 years, 12.5% (10/80) occupied among 20-30 years and 8.7%(07/80) among 51-60 years. Least was noted among 61-70 years (2.5%). The youngest being 21 years old and the eldest, 69 years old. The mean age was 42 years.
On gender distribution females were predominantly (62.5%) presented with thyroid nodules when compared to males (37.5%).
In our study among 80 thyroid Nodules, Colloid Nodule noted in 42.5% cases (34/80), Nodular goitre in 27.5% (22/80), Hashimotos thyroiditis and follicular adenoma constituted 12.5% (10/80) each and malignancy was reported in 5% (04/80) cases.
Table 1
USG findings of thyroid nodules
Accordingly, we evaluated the following parameters in thyroid masses: size and location of the lesion, number of nodules, echogenecity, internal consistency, calcification, haemorrhage, necrosis, thyroid capsule invasion, vascular invasion, trachea and oesophageal involvement, mediastinal extension, and adenopathy.
In our study Solitary nodules constituted 58.5% (47/80) and multiple nodules constituted 41.2% (33/80). Based on echogenicity, the nodules in our investigation varied in size from 5mm to 5 cms. 82.5% (66/80) nodules were hypoechoic, 17.5% (14/80) nodules were hyper echoic. All the benign thyroid nodules showed well defined margins in 92.5% cases (74/80) and 7.5% (06/80) of malignant thyroid nodules showed ill defined margins. Central vascularity was present in 17.5% (14/80) cases and no significant central vascularity was seen in82.5% (66/80) cases. Calcification was seen in 2.5% (02/80) cases. Microcalcification or macrocalcification were seen in these calcifications. In our dataset, microcalcifications were only found in papillary carcinomas and only in 02/04 malignant patients. Macrocalcification was seen in 01/04 malignant cases. No calcification was observed in 97.5% (78/80) cases. Both Solid and cystic areas were identified in 7.5% (06/80) cases.
In our study 42.5 % (34/80) reported as colloid nodule and 21.5%(17/80) as nodular goitre. Follicular adenoma IN 10% (08/80) and Malignancy in 7.5% (06/80) cases.
Table 2
USGand FNAC Findings correlation
Statistical analysis
Statistical analysis was done to find out the value of HRUSG in detecting thyroid nodules.
Sensitivity = TP = 66.6%
TP+FN
Specificity = TN = 100%
TN+FP
PPV = TP = 100%
TP+FP
NPV = TN = 97.3%
TN+FN
Accuracy = TP+TN = 97.5%
TP+TN+FN
To summarise the findings, the false negative rate was 10.2%. The sensitivity and specificity were respectively 66.6 percent and 100 percent. The negative predictive value was 97.3 percent, while the positive predictive value was 100%. HRUSG has 97.5 percent accuracy in distinguishing benign from malignant thyroid nodules.
Discussion
In our study majority (48.5%) of the cases were present between 41-50 years. Least was noted among 61-70 years. The mean age was 42 years. In Baby Manoj PP et al study 12 the majority of the patients (52%) were between the ages of 40 and 49. The mean age was 39 years.
Females were predominantly (62.5%) presented with thyroid nodules when compared to males (37.5%) in our study. Similar findings were observed by various studies. Such as in study conducted by Anuradha Kapali et al 13 10 were males and 47 were females. In Chinta Vittal Prasad et al study14 89 were female and 11 were male. In Gururaj Sharma et al study15 there were 118 females and 20 males .In Baby Manoj PP et al study 12 there were 22 (88%) females and 3 males (12%). Hence our findings were correlating with respective studies.
Our study observed 75 benign thyroid nodules and 04 malignant nodules out of 80 thyroid nodules. Our study findings were collaborating with Gururaj Sharma et al study 15 where he also observed 124 benign thyroid nodules and 14 malignant nodules.
Comparative studies related to USG distribution
In our study Solitary nodules constituted 58.5% (47/80) and multiple nodules constituted 41.2% (33/80). The nodules in our research varied in size from 5mm to 5 cm. Based on echogenicity 82.5% (66/80) nodules were hypoechoic, 17.5% (14/80) nodules were hyper echoic. All the benign thyroid nodules showed well defined margins in 92.5% cases (74/80) and 7.5% (06/80) of malignant thyroid nodules showed ill defined margins. Central vascularity was present in 17.5% (14/80) cases and no significant central vascularity was seen in 82.5% (66/80) cases. Calcification was seen in 2.5% (02/80) cases. Microcalcification or macrocalcification were seen in these calcifications. In our dataset, microcalcifications were only found in papillary carcinomas and only in 02/04 malignant patients. Macrocalcification was seen in 01/04 malignant cases. No calcification was observed in 97.5% (78/80) cases. Both Solid and cystic areas were identified in 7.5% (06/80) cases.
In a study conducted by Anuradha Kapali et al 13 Hypoechoic nodules accounted for 51% of the total, whereas hyperechoic nodules accounted for 49% of the whole. In 68.4 percent (39) of the patients, central vascularity was found, whereas 31.5 percent (18) of the patients had no substantial central vascularity. There was no calcification in 54.3 percent (31) of the patients, macro calcification in 26.3 percent (15) of the patients, micro calcification in 17.5 percent (10) of the patients, and one patient had both macro and micro calcification (1.7 percent). In 23 percent of the patients, cystic regions were found, two patients had honeycombing, and 56.1 percent (32) of the patients had no cystic areas.
In Baby Manoj PP et al study 12 by According to HRUSG, 40% of lesions were hypoechoic, 32% were mixed echogenic, and 8% were hyperechoic. In 28% of instances, there was a perilesional halo, and in 20% of cases, there was calcification. In 20% of instances, a single nodule is found, whereas in the other 80%, several nodules are seen. In 52 percent of cases, the boundary was clearly defined, whereas in 48 percent, it was not. Sixty-eight percent of the lesions were solid, whereas 32 percent were solidcystic. In a study done by Gururaj Sharma et al study.15 On USG, all of the nodules in their series that were identified as malignant were solid or mainly solid lesions. The majority of malignant nodules (12/14) had hypoechoic internal echo texture, while the majority of benign nodules (89/124) had either hyperechoic or anechoic internal echo texture (cystic). The majority of malignant nodules (10/14) had poorly defined borders, which were either vague or irregular in form, while the majority of benign nodules (102/124) had a smooth, well-defined contour. Calcifications were seen in 11 of 14 cancerous nodules and 28 of 124 benign nodules. Microcalcifications were found only in papillary carcinomas in our study, with 8/9 patients having microcalcifications. 5/14 cancers and 28/124 benign nodules had macrocalcification. The majority of malignant lesions (12/14) had internal vascularity inside the nodule, while benign nodules were avascular or had a perinodular vascular pattern.
Comparative studies related to statistics
The false negative rate in our research was 10.2 percent. The sensitivity and specificity were respectively 66.6 percent and 100 percent. The negative predictive value was 97.3 percent, while the positive predictive value was 100%. HRUSG has 97.5 percent accuracy in distinguishing benign from malignant thyroid nodules. In contrast, according to a research done by Baby Manoj PP et al 12, ultrasonography has a sensitivity of 80%, specificity of 75%, positive predictive value of 44%, negative predictive value of 93%, and accuracy of 76%. Sensitivity, specificity, positive predictive value, and negative predictive value of 72 percent, 88 percent, 67 percent, and 90 percent, respectively, were reported in the Chinta Vittal Prasad et al 14 research.
Conclusion
HRUSG is a sensitive and specific imaging modality for evaluating thyroid nodules, and it has a high degree of accuracy in distinguishing benign from malignant thyroid nodules. The false negative rate in our research was 10.2 percent. The sensitivity and specificity were respectively 66.6 percent and 100 percent. The negative predictive value was 97.3 percent, while the positive predictive value was 100%. 97.5 percent accuracy was achieved.
