Clinical data: A 54-year-old woman was referred for evaluation of a nodule. She has been treated for hypothyroidism for seven years.

Palpation. No abnormality.

Laboratory test: TSH 1.10 mIU/L on daily 75 microgram levothyroxine.

Ultrasound. The thyroid had numerous moderately hypoechoic fields corresponding to the underlying thyroiditis. The echogenicity index exceeded 50%. There was a hypoechoic nodule in the right lobe. The shape was close to consider nonparallel, but the largest width exceeded the largest depth. The nodule showed irregularities at the border. On the degree of these irregularities, the possibility of irregular borders can be raised. The intranodular vascularization was extremely increased.

Cytology was performed form the hypoechoic nodule and resulted in Hashimoto's thyroiditis.

Comments.

1. Nonparallel orientation is defined as the largest depth to exceed the largest width or length, taller-than-wide or taller-than-long shape, respectively. Although in certain sections the depth exceeded the width, bit this was not true if we related the largest depth to the largest width. Therefore, the nodule did not present nonparallel orientation.
   
2. It is equivocal whether the borders should be considered as irregular or should not.