Healthy Living

What is Tonsil Grading?

What is Tonsil Grading?

In the back of the throat, there is a lymphoid group of tissues known as the tonsils. In the throat, there are four groups of tonsillar tissues, including palatine, lingual, adenoid, and nasopharyngeal. Each tonsil is covered by pink mucosa and is composed of tissue similar to lymph nodes. Pits running through the mucosa of each tonsil are called crypts. Tonsils help to fight infections and are a part of the lymphatic system. Removal of tonsils does not seem to increase the chances of infections. In response to infections, the tonsils swell and may vary in size.

Tonsils can get affected by abscesses around the tonsils, infections of small pockets within the tonsils, and chronic tonsillitis. If there are symptoms of enlarged or infected tonsils, then you should see a doctor.

Methods used to check the tonsils

The various methods to check tonsils are medical history, physical examination of the patient, throat cultures/strep tests, which help in determining infections, blood tests, which also helps in determining infections, sleep studies, or a polysomnogram, which helps in determining the disturbances of sleep that are caused by enlarged tonsils.

Symptoms of tonsillitis

The most common sign is swelling, but other symptoms include:

  • Change in the voice
  • Redness of the tonsils
  • Throat becomes sore
  • Some may even experience pain in the ear
  • Difficulty swallowing
  • Lymph nodes in the neck get swollen
  • Fever
  • Bad breath

Enlarged tonsils can cause the following symptoms:

  • Nose gets blocked
  • Ear infections which recur
  • Daytime noisy breathing
  • Snoring
  • Chronic runny nose
  • Breathing through mouth
  • During sleep, the person becomes restless

Below are the types of tonsils:

  • Palatine tonsils – located at the back of the throat next to the uvula. Mostly they are referred to as tonsils. They usually get infected by strep, bacterial herpes virus, or Epstein Bar virus / infectious mononucleosis. They can cause obstructions, such as snoring, difficulty swallowing food, restless sleep, apnea, and bedwetting. They can be significantly large. If the size of palatine tonsils is evaluated early, then it can help prevent orthodontic abnormalities that are caused by upper airway obstruction.
  • Lingual tonsils - they are located at the back of the tongue. Compared to palatine tonsils or adenoid tonsils, they do not get infected frequently. If they do, then it is a matter of concern. The infection of lingual tonsils can cause difficulty in breathing or swallowing. Patients with sleep apnea may have swollen lingual tonsils. If a lingual tonsil enlarges, it can cause apnea to become severe.
  • Adenoid and nasopharyngeal tonsils - they are located at the back of the nose. They are partially surrounded by the Eustachian tubes. They can cause conditions such as difficulty in nasal breathing, ear infections, and sinusitis.

Oropharyngeal evaluation gives a better understanding of the patient’s risk of nocturnal airway closure; however, a single standard method has not been developed yet, since the size of the airway is determined by the hard and the soft palate and is likely related to congenital and acquired factors.

Tonsil size or grading

The size of the tonsils is graded on a scale from one to four. Four is the largest size. The tongue should be rested comfortably in the mouth for best judgment of the tonsil. Palatine tonsils are graded based on how much the airway is obstructed due to the tonsil protruding from either side of the oropharynx.

  • Brodsky grading scale
    • Size 0: it means the tonsils are absent or have been removed.
    • Size 1: barely visible. This is the normal tonsil size. It indicates that the tonsil extends to the pillars.
    • Size 2: the tongue tissue is not beyond the tonsillar pillars. This is also normal tonsil size. It indicates that the tonsils extend to the pillars.
    • Size 3: up to 75% of oropharyngeal airway is taken up by the tonsil. The tonsils are enlarged and seen with infection. It indicates that tonsils extend beyond the pillars, but stop short of the midline.
    • Size 4: more than 75% of airways is taken up by the tonsil. It is seen with significant or almost touching. It indicates that tonsils extend to the midline and are almost touching each other.

Along the back wall of the throat are scattered blebs of tonsils known as Waldeyers ring. In a person, even after tonsillectomy, Waldeyers ring play a vital role in causing pharyngeal strep tonsillitis.

The tonsils are assessed by making the patient open his mouth and depressing the tongue. A tongue blade is used, while a penlight is used for inspection of the back of the throat of the patient to check for pink, symmetrical and normal-sized tonsils. Bright-red, enlarged tonsils, or white or yellow tonsils are abnormal findings. Inflammation of the tonsils is known as tonsillitis.

  • The Mallampati score is defined as:
    • Class I: soft palate, fauces, uvula, posterior, and anterior pillars visible.
    • Class II: soft palate, fauces, and uvula visible.
    • Class III: soft palate, fauces, and only base of uvula visible.
    • Class IV: soft palate not visible.

A modified version of this was developed by Friedman and colleagues. The grading scale assessed the size of the upper airway. It attempted to find out which surgical intervention for obstructive sleep apnea would likely be more successful.

In palate grading, the patient is asked to open his mouth wide without protruding the tongue out. The procedure is repeated five times. There can be variations sometimes with different examinations.

  • Friedman grading is done on the basis of the appearance of the palate. It is done as follows:
    • Grade 1: the entire uvula and tonsils of pillars can be visualized
    • Grade 2: the uvula can be visualized but not the tonsils
    • Grade 3: the soft palate can be visualized but not the uvula
    • Grade 4: only the hard palate can be visualized

The primary difference in both the assessments is that in the Friedman system the tongue is not protruded out. This scale is also referred to as the Modified Mallampati Scale. By combining the palate grade, tonsil size, and BMI, Friedman created a staging system. This would help to determine the surgical practices for obstructive sleep apnea. Lower staging would predict successful treatment of obstructive sleep apnea by uvulapatopharyngoplasty only. Also, the condition of the upper airway can be obtained from the uvula. Swelling at the edge of the soft palate may indicate snoring. A long or wide uvula causes airway crowding, and this may result in sleep apnea. Another factor in assessment of the airway crowding is the size of the adenotonsillar tissue. Even though enlarged tonsils contribute to airway crowding, soft tissue hypertrophy seems to play a less significant role. Tongue positions and volume likely affect patency, and in cephalometric studies, it has found to be correlated with obstructive sleep apnea. Tongue scalloping describes that the tongue is large or the lower jaw is small.

  • The above two scores of Brodsky and Friedman can be combined to find the stage of the person for severity of sleep apnea.
    • Stage I: the palate position is of 1 or 2 and the tonsil size is 3 or 4. The BMI of the person is less than 40 kg/ m2.
    • Stage II: defined by the palate position of 1 or 2 and the tonsil size is 0, 1, or 2. If the palate position is 3 and 4, then the tonsil size is 3 or 4. The BMI of the person is less than 40 kg/ m2.
    • Stage III: defined by palate position of 3 or 4 and the tonsil score is 0, 1, or 2. BMI of the person is more than 40 kg/ m2.

Brodsky developed a grading system. With the help of this grading system, it was possible to describe the tonsil enlargement. This helps the doctor to find any other underlying medical conditions. For this assessment, anterior to the circumvillate papillae, the tongue blades are pressed gently on the anterior two thirds of the tongue. Gagging may result in a false positive test, since gagging causes the tonsils to move medially, which can make them appear larger. The parameters to be considered are:

  • Distance between the anterior tonsillar pillars midway between the tongue and the palate.
  • Minimum distance between the medial aspects of the two tonsils.

To calculate, in percent, the occlusion of the oropharyngeal airway:

Percent occlusion of the oropharyngeal airway = (((distance between the anterior pillars) – (distance between tonsils)) / (distance between the anterior pillars)) * 100

  • If the percent occlusion is 0%, it belongs to grade 0
  • If the percent occlusion is 1 to 24.9%, it belongs to grade 1+.
  • If the percent occlusion is 25 to 49.9%, it belongs to grade 2+.
  • If the percent occlusion is 50 to 75%, it belongs to grade 3+.
  • If the percent occlusion is 75% and above, it belongs to grade 4+.

Grade 0 is when the tonsils are in the tonsillar fossa. The tonsils in this grade do not extend medially to the anterior tonsillar fossa.


Enlargement of the tonsils can have substantial ill effect on the health of the child or adult.

Enlargement of tonsils causes difficulty in swallowing, limits the airflow, causes pain or discomfort and obstructive sleep apnea. If the obstructive sleep apnea is long term, then it can cause delay in the growth and development of a person, behavioral problems, and also cardiopulmonary problems. To check the airway muscle tone in children, clinicians look for the symptoms, such as snoring, daytime fatigue, and trouble in concentrating. This is to rule out obstructive sleep apnea. Enlarged tonsils can limit the airflow. In the etiology of obstructive sleep apnea, this can be a significant risk factor. Children should be evaluated for tonsil size. Hence, the reliability of this test is important.

In clinical settings, it is important to document tonsil size and tonsil grading, as well as perform reliable monitoring. The grading scale of tonsils helps the clinicians to record the change in the tonsil size and communicate accordingly. Various grading systems may provide results that may be interpreted differently by the users. This makes the assessment of tonsil size by using tonsil grading system unreliable. Due to the variability in tonsil grading systems, there can be confusion in communicating the tonsil size. Hence, it is necessary to compare the existing tonsillar grading scales and to check the reliability and reproducibility. However, the reliability of this needs to be studied. Due to recurrent infection or as a part of generalized lymphoid hypertrophy, tonsils undergo hypertrophy. There is a good correlation between clinical tonsil grade and tonsil volume in snorers and obstructive sleep apnea.

Most reliable system

The Brodsky grading scale and Friedman grading scale are the two most widely used grading scales. In the Brodsky grading scale, the tonsils are graded from 1 to 4, which depend on the percentage of oropharyngeal airway that is occupied by the tonsil. In the Friedman grading scale, the tonsil size is classified on the basis of the location of the tonsil in relation to its surrounding structures in the oral cavity.

A study that was recently conducted measured the reliability of three scoring methods, including the Brodsky grading scale, 3- , and 5- grade scales. The 3-grade scale has a wide grade interval, so it is simpler to use, but higher reproducibility was found in the Brodsky grading scale and 5-grading scale. Visual objective examination of tonsil size is the pragmatic standard method to assess the eligibility for adenotonsillectomy. The children can expose the tonsil freely from different angles in this method.

In this study, it was found that the most consistent results can be obtained by the Brodsky scale in comparison to the Friedman scale and a three-grade scale. In clinical and research work, it is recommended to use the Brodsky scale to grade tonsil size. The most reliable measurements both between the observers and between different measurements by the same observer can be obtained by the Brodsky scale. In studies conducted in trial, it has been found that the Brodsky scale had reached very close to the accepted reliability. The Brodsky scale assesses the percentage of the airway taken up by the tonsil, whereas Friedman scale grades the tonsil with respect to its position relative to its surrounding structures. The modified three-grade scale evaluates the relative position of the tonsils like the Friedman scale. It was a unique scale, but in studies it was known to perform poorly.

  • The more is the tonsillar grade the lower is the transversal dimension of the maxillary arch.
  • Ratio of the depth of palatal vault to the width of the maxillary interfist molar is first taken and this ratio is correlated to grade.
  • The chances of developing class II is higher in grade 4 than in grade 0 patients.
  • Patients with grade 3 and 4 have higher chances of developing an open bite than patients of grade 1 and 2.
  • Posterior cross bite with lateral deviation of the mandible is linked to grade 4 patients.