Immunology Review Corner

Prepared by Thao N. Tran, M.D., Stony Brook University Hospital-SUNY, and Karla Lowe, M.D., Walter Reed Medical Center.

Chapter 47: Anatomy and Physiology of the Nose and Control of Nasal Airflow

1. Particles with which of the following aerodynamic equivalent diameter (AED) fail to deposit in the upper respiratory tract upon nasal inspiration?
a. 15 micrometers
b. 30 micrometers
c. 75 micrometers
d. 180 micrometers

2. Persistence of the oronasal membrane is the congenital malformation known as:
a. Choanal atresia
b. Cleft palate
c. Haller cells
d. Concha bullosa

3. Which is the following is correct about normal nasal breathing?
a. The narrowest point of the nasal airway is the nasal vestibule
b. Majority of the airflow is directed toward the middle and superior turbinates
c. During inspiration, the majority of the nasal airflow is turbulent
d. Flaring of the nares helps direct airflow towards the olfactory region

4. Which of the following epithelial cell types is found in the respiratory nasal epithelium?
a. Clara cells
b. Basal cells
c. Serous cells
d. Brush cells

5. The trigeminal nerve in the nasal epithelium is important in the respiratory reflex. Stimulation of the trigeminal nerves can lead to sneezing, nasal hypersecretion, expiration followed by apnea, and closure of the larynx. Which of the following is also true about the trigimenal nerve in the nasal epithelium?
a. Acts as a chemoreceptor for odorants in the olfactory area
b. Detects sulfur dioxide
c. Stimulation leads to vasoconstriction of blood vessels
d. Stimulation can lead to tachycardia

6. Horner’s syndrome results in a loss of sympathetic nerve supply to the nasal epithelium, which leads to:
a. Contralateral nasal congestion, and a decrease in nasal resistance to airflow
b. Bilateral nasal congestion, and an increase in nasal resistance to airflow
c. Contralateral nasal congestion, and an increase in nasal resistance to airflow
d. Ipsilateral nasal congestion, and an increase in nasal resistance to airflow

7. Nasal resistance is highest in which of the following patients?
a. A 4-month-old infant
b. A 4-year-old child
c. A 14-year-old teenager
d. A 34-year-old adult

8. Application of a crutch to the axilla of a sitting patient causes which of the following?
a. Bilateral nasal congestion
b. Bilateral nasal decongestion
c. Ipsilateral nasal congestion, contralateral nasal decongestion
d. Ipsilateral nasal decongestion, contralateral nasal congestion

9. Which of the following statement about nasal airflow is correct?
a. Puberty, menstruation and pregnancy are often associated with improved nasal airflow.
b. Blockade of the trigeminal nerve can lead to a loss of a cool sensation with inspiration, resulting in a sensation of nasal obstruction.
c. Menthol improves nasal airflow by causing vasoconstriction of the nasal venous sinuses.
d. Increase in blood carbon dioxide level leads to a nasal vasodilator response (consequently, a decrease in nasal airflow).

10. Which of the following is the major receptor type on smooth muscle of the nasal venous sinuses?
a. Alpha(1)-adrenergic
b. Alpha(2)-adrenergic
c. Alpha(3)-adrenergic
d. Alpha(4)-adrenergic

11. Which of the following is true about histamine receptors in the nasal airway?
a. Only the H1 receptor is involved in the dilation of the nasal venous sinuses.
b. Both the H1 and H2 receptors are involved in dilation of the nasal venous sinuses.
c. The H2 receptor is important in sneezing, itching, and hypersecretion.
d. Histamine is a vasoconstrictor, causing congestion of the nasal venous sinuses.

Answers:
1. d, page 775
2. a, page 776
3. c, pages 775-777
4. b, page 778
5. b, page 779
6. d, pages 780-781
7. a, page 781
8. c, page 783
9. b, pages 783-784
10. a, page 784
11. b, page 785