Indian Journal of Radiology and Imaging Indian Journal of Radiology and Imaging

RADIOLOGICAL QUIZ
Year
: 2002  |  Volume : 12  |  Issue : 1  |  Page : 123--124

Radiological quiz - chest


NS Kumar, BS Arun Babu, S Moorthy, NK Prabhu, KP Sreekumar, AK Pillai 
 India

Correspondence Address:
N S Kumar
India




How to cite this article:
Kumar N S, Arun Babu B S, Moorthy S, Prabhu N K, Sreekumar K P, Pillai A K. Radiological quiz - chest.Indian J Radiol Imaging 2002;12:123-124


How to cite this URL:
Kumar N S, Arun Babu B S, Moorthy S, Prabhu N K, Sreekumar K P, Pillai A K. Radiological quiz - chest. Indian J Radiol Imaging [serial online] 2002 [cited 2019 Aug 25 ];12:123-124
Available from: http://www.ijri.org/text.asp?2002/12/1/123/30555


Full Text

Twenty two year old male patient presented with a history of recurrent respiratory tract infections of eight years duration.

On auscultation, there was bilateral coarse crepitations and rhonchi. Blood counts were within normal limits and there was no eosinophilia. Frontal chest radiograph and HRCT was done. What is the diagnosis?

 View Answer

 Radiological Diagnosis



Tracheobronchomegaly (The Mounier-Kuhn Syndrome)

Described first in 1932 by Mounier-Kuhn[1], this syndrome is a rare disorder of unknown etiology with male predominance, characterized by marked dilatation of trachea and central bronchi. In 1962 Katz et al [2] introduced the term tracheobronchomegaly. It is also known by other names viz, tracheal diverticulosis, tracheocele, tracheomalacia, trachiectasis, megatrachea and tracheobroncheopathia malacia[2],[3]

Clinical symptomatology is similar to that of chronic respiratory infections with cough, recurrent fever, sputum production, dyspnoea and cyanosis. Finger clubbing and pulmonary consolidation can also occur. The duration of symptoms is usually long and may date back to childhood. Frequently patients have associated bronchiectasis.

The pathology is a defect in the elastic and muscular tissues of the trachea and main bronchi. This results in marked enlargement of the trachea and bronchi during inspiration and a tendency towards total collapse during expiration. First to fourth order bronchi are affected. There is abrupt transition from diseased to normal bronchi. The bronchi that arise from bronchiectatic segments remain patent as opposed to mucus plugging in other forms of bronchiectasis. The terminal airways appear normal. There is increase in dead space, tidal volume and diminished clearing of secretions[4]. There may be large out-pouching of the tracheal wall and redundant folds of mucus membrane.

Tracheobronchomegaly has been reported in association with acquired cutis laxa, Ehler-Danlos syndrome[3] and ankylosing spondylitis (7). An autosomal recessive type of inheritance is seen in some cases[5]. There is a racial predisposition and this condition is more in blacks[6]. Anatomic variants of lungs, ribs and bronchial tree are more common in these patients[4].

Chest radiograph shows marked dilatation of the trachea [Figure 1]. The width of the tracheal air column may equal that of the thoracic vertebral column [2],[3],[4]. The normal coronal diameter of the trachea is less than 26mm in men and 23mm in women.

Expansion of the trachea and sometimes major bronchi during inspiration and complete collapse during expiration and coughing are evident on fluoroscopic examination.

Bronchography demonstrates dilated trachea and bronchi. Mucous membrane folds and saccular pouches are also seen [2],[4].

In the HRCT scan dilatation of the tracheobronchial tree is well seen [Figure 2] and [Figure 3] Complications like bronchiectasis and segmental consolidations are better seen in the HRCT. Coronal diameter of the airways in HRCT is less than that seen in radiography by about 3-4mm.

In our case the coronal diameter of the trachea was 30mm, which is very high compared to normal.

References

1Mounier-Kuhn P, Dilatation de la trachee; constatations radiographiques et bronchoscopiques. Lyon med 1932; 150: 106-109.
2Katz I, LeVine M, and Herman P Tracheobronchiomegaly: Mounier Kuhn syndrome. Am J Roentgenol Rad Therapy and Nuclear Med 1962; 88: 1084-1094.
3Wonderer AA, Elliot FE, Goltz RW, and Cotton EK. Tracheobronchiomegaly and acquired cutis laxa in child: physiologic and immunologic studies. Pediatrics 1969; 44: 709-714.
4Bateson EM and Woo-Ming M. Tracheobronchomegaly. Clin Radiol 1973; 24: 354-358.
5Johnston RF and Green RA. Tracheobronchiomegaly: report of five cases and demonstration of familial occurrence. Am Rev Resp Dis 1965; 91: 35-50.
6Padley S, Verma N, Flower CDR: Case report; Tracheobronchomegaly in association with ankylosing spondylitis, Clin Radiol 1991; 43: 139-141.