대한흉부영상의학회 Weekly Chest Cases

Case No : 455 Date 2006-07-17

Courtesy of Hyun Ju Lee, MD. / Seoul National University Hospital, Seoul, Korea
Age/Sex 50 / M
Chief ComplaintDyspnea Chest CT was performed 22 Jun 2006

Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
Figure 7
Figure 8

Diagnosis With Brief Discussion

Diagnosis: Mechanical Ventilation Associated Reticular Opacity (Lung Fibrosis) in Anterior Lung in ARDS
Radiologic Findings: 2006.6.1 Chest PA: No abnormality

2006.6.12 Chest PA: Diffuse ground-glass opacification in both lungs

2006.6.15 Chest PA: Diffuse ground-glass opacification and confluent consolidation areas in both lungs

2006.6.22 Chest CT: Traction bronchiectasis and air cysts suggesting lung fibrosis is predominantly found in anterior lung.
Brief Review: In one study, CT Abnormalities at Long-term Follow-up Acute Respiratory Distress Syndrome (ARDS) was evaluated and following results were reported (1).

1. On long-term follow-up CT scans, a coarse reticular pattern was the single most frequent pattern, (85%) and was strikingly more extensive anteriorly.

2. The extent of a reticular pattern on long-term follow-up CT scans was directly correlated with the extent of ground-glass opacification on initial CT.

3. There were correlations between the extent of a reticular pattern on the follow-up CT scans and the total duration of mechanical ventilation, the duration of pressure-controlled inverse-ratio ventilation, and the duration of synchronized intermittent mandatory ventilation.

4. The extents of a reticular pattern and of ground-glass opacification combined showed a significant negative correlation with the forced vital capacity and a positive correlation with the residual volume and the ratio of residual volume to total lung capacity.

The anterior distribution of the reticular pattern at follow-up seems to be a distinctive feature and has been commented on in only one previous report (2) on three patients with severe ARDS in whom follow-up CT scans revealed an anteriorly distributed coarse reticular pattern with associated traction bronchiectasis. The authors (2) suggested that the anterior reticular pattern resulted from alveolar overdistention in "unprotected" nonconsolidated lung. During the acute phase of ARDS, hyperattenuating areas of unaerated or collapsed parenchyma are typically seen in dependent parts of the lung (3, 4). There is some evidence to support the view that collapsed or consolidated lung is protected from the effects of alveolar overdistention: A negative correlation was noted between the extent of a reticular pattern on follow-up CT scans and the extent of intense parenchymal opacification on initial CT scans.
References: 1. Desai SR, Wells AU, Rubens MB, Evans TW, Hansell DM. Acute respiratory distress syndrome: CT abnormalities at long-term follow-up. Radiology. 1999;210:29-35.

2. Finfer S, Rocker G. Alveolar overdistension is an important mechanism of persistent lung damage following severe protracted ARDS. Anaesth Intensive Care 1996; 24:569-573.

3. Gattinoni L, Mascheroni D, Torresin A, et al. Morphological response to positive end expiratory pressure in acute respiratory failure: computerized tomography study. Intensive Care Med 1986; 12:137-142.

4. Gattinoni L, Pelosi P, Pesenti A, et al. CT scan in ARDS: clinical and physiopathological insights. Acta Anaesthesiol Scand 1991; 35:87-96.
Keywords: Lung, Iatrogenic lung disease// Embolic, Thromboembolic,

No. of Applicants : 31

▶ Correct Answer : 13/31, 41.9%

- Pgimer, Chandigarh, India Ram Prakash Galwa
- Mubarak Al Kabeer Hospital, Kuwait Varghese Sajeev P.J.
- EKH-Berlin, Germany Michael Weber
- Monaldi Hospital, Naples, Italy Gaetano Rea
- DFCI, Boston, USA Jyothipriya
- Fourth Terrace Diagnostic Center, Nassau, Bahamas Trupti Dabholkar
- Hangang Sacred Heart Hospital, Korea Eil Seong Lee
- Radiologie Guiton, La Rochelle, France Denis Chabassiere
- National Taiwan University Hospital, Taiwan Yu-Feng Wei
- Homs National Hospital, Homs, Syria Rami Abou Zalaf
- Nirman Hitech Diagnostic Center, Mumbai, India Minal Seth
- Sam Anyang Hospital, South Korea Jae Seung Seo
- Diskapi Yildirim Beyazit Hospital, Ankara, Turkey Meric Tuzun

▶ Correct Answer as Differential Diagnosis : 8/31, 25.8%

- Inje University Ilsan Paik Hospital, Seoul, Korea Bae Geun Oh
- KAUMS, Kashan, Iran Ebrahim Razi
- Gwangmyoung Sungae Hospital, Korea Jiyong Rhee
- Airforce Hospital, Korea Hyun Seok Choi
- Yonsei University Severance Hospital, Korea Yong Eun Chung
- Yonsei University Shinchon Severance Hospital, Korea Hye-Jeong Lee
- Max Hospital, New Delhi, India Vickrant Malhotra
- China Medical University Hospital,Taiwan Jun-Jun Yeh

▶ Semi-Correct Answer : 1/31, 3.2%

- Hopital Calmette, Chru, Lille, France Toledano Manuel

대한흉부영상의학회 Korean Society of Thoracic Radiology

Archive of Old Cases

Case No : 455 Date 2006-07-17

Discussion

No. of Applicants : 31