Hydatid cyst of the parotid gland.

Primary hydatid cyst of the parotid gland is extremely rare, even in the endemic areas. A 23-year-old woman presented with slowly progressive swelling in the right periauricular region. Computed tomography (CT) scan of the head and neck revealed a round, well-demarcated water-density mass in the right parotid gland. At the operation, the cystic mass replacing most of the superficial part of right parotid gland was demonstrated. Superficial parotidectomy was carried out. Histopathological examination confirmed the diagnosis of hydatid disease. CT scan is a valuable imaging method for diagnosis of parotid cystic lesions; however, other acquired and congenital cystic lesions of parotid gland may have similar appearance and should be differentiated. Where the incidence of the disease is high, hydatid cyst of parotid gland should be considered in the differential diagnosis of lesions causing swelling of the parotid area.

Assessment of nasal volume and cross-sectional area by acoustic rhinometry in a sample of normal adult Iranians.

Assessment of nasal airway is helpful in understanding nasal breathing function. Acoustic rhinometry is one of the most commonly-used objective measurements of nasal airway. This test has the ability to measure the volume and the cross-sectional area of the nose in different distances. It also determines the site of minimal cross-sectional area. These variables are different in various races. Defining these normal values in adult Iranian population, as a criterion for diagnosis and treatment of nasal diseases can be very helpful.One hundred eighty adult Iranians (18 - 60 years old) without nasal breathing complaints underwent acoustic rhinometry. The mean volume and minimal cross-sectional area of the nose and also correlation of these variables with age, sex, height, weight, smoking habit, and topical nasal decongestion were assessed. In this sample, total nasal volume was 8.12+/-0.94 cm3 and total minimal cross-sectional area was 0.9+/-0.17 cm2 before decongestion. There was no correlation between these values and age, sex, height, weight, and smoking habit. There was a significant increase in volume and cross-sectional area after decongestion. Because of the differences in volume and minimal cross-sectional area in various races, measurement of these values in Iranian population is a proper way for diagnosis of rhinologic diseases and planning the appropriate treatment (medical or surgical). It is also helpful for comparison of preoperative and postoperative results after nasal surgeries.