Opaque hemithorax (whiteout): A literature review exploring its causes,potential use of thoracic ultrasound and the role of physiotherapy

Abstract

PURPOSE:

Complete whitening of one half of the thorax on a chest radiograph (CXR) is termed an opaque hemithorax. It often indicates the presence of significant pathology resulting in respiratory compromise. There are numerous causes of an opaque hemithorax, but these are not immediately apparent on CXR. Thoracic ultrasound (TUS) has a higher accuracy to differentiate between opacities on CXR and may help to correctly identify underlying pathologies. The purpose of this literature review is to report the causes of an opaque hemithorax, identify how TUS can assist diagnosis and explore the role physiotherapy has opaque hemithorax management.

METHODS:

A systematic search was conducted (PubMed, Medline, Embase, CINAHL, AMED and BNI) up until March 2018. Inclusion: Adults. Primary research reporting a complete opaque hemithorax on CXR.

RESULTS:

1117 papers were identified in search. Following inclusion and exclusion criteria: 58 papers were selected. 54 papers were case reports and four were observational studies. The causes of the opaque hemithorax were collated and divided into 16 categories. Eight studies included the use of TUS to differentiate the cause of the opaque hemithorax. Two studies reported the involvement of physiotherapy in opaque hemithorax.

CONCLUSIONS:

Numerous pathologies can cause an opaque hemithorax on CXR making differential diagnosis difficult. Even when mediastinal shift is present it does not appear to be a reliable way to identify the underlying cause. Thoracic ultrasound has the potential to much more accurately differentiate between pathologies. This would assist physiotherapists to identify patients amenable to physiotherapy treatment techniques.

Keywords

Opaque hemithorax whiteout thoracic lung ultrasound physiotherapy

1 Introduction

Complete whitening of one half of the thorax on a chest radiograph (CXR) is termed an opaque hemithorax and commonly referred to as a “whiteout”. It often indicates the presence of significant pathology resulting in respiratory compromise necessitating medical intervention and, on occasion, a referral for “chest” physiotherapy. There are numerous causes of an opaque hemithorax, but these are not all immediately apparent on CXR which makes differential diagnosis difficult. One method of diagnosis is based on the volume of the affected hemithorax as determined by the positional shift of the mediastinum or more specifically the trachea on CXR. The accuracy of this technique is, however, questionable. According to a recent systematic review thoracic ultrasound (TUS) has a higher accuracy to differentiate between opacities on CXR [1] and may help to correctly identify the underlying pathologies causing an opaque hemithorax. The purpose of this literature review is to report on the varied causes of an opaque hemithorax, identify how mediastinal positioning can assist in its diagnosis as well as explore the roles TUS and physiotherapy have in the management of an opaque hemithorax.

2 Methods

A systematic search of electronic databases (Medline, Embase, PubMed, CINAHL, AMED and BNI) was conducted up until March 2018. The following search terms were combined: “hemithorax” or “hemi-thorax” or “hemithora*” or “opaq*” or “opac*” or “whiteout” or “white-out” or “white out”. Inclusion criteria: Primary research published in any language reporting a complete opaque hemithorax on CXR. Study subjects are adults (18 years or over). Conference abstracts published in English were also included. Exclusion: Animal or tissue studies. Duplicate papers within or between databases were excluded. The remaining full-text papers were screened by two reviewers (SH and LH). Discrepancies between reviewers were resolved through consensus. Papers that met the inclusion criteria had the following information extracted: Cause of the opaque hemithorax, report of mediastinal shift to determine opaque hemithorax on CXR, use of TUS to assist in diagnosis and involvement of physiotherapy within the management strategy of an opaque hemithorax.

3 Results

A total of 1117 papers were identified in the database searches. Following removal of duplicates and application of the inclusion and exclusion criteria 58 full papers or abstracts were selected (Fig. 1). Four of the papers were observational studies [2 –5] and included a total 249 subjects between them. Two of the four observational studies were reported by the same team from Taiwan [4, 5]. The other two separate papers both reported on an Indian (Indian subcontinent) subject population [2, 3]. Fifty-four (93%) of the papers were case reports [6 –58] or case series [59] with many reporting rare and unusual causes of opaque hemithoracies (Table 1).

Fig.1

Search strategy.

Table 1

Extracted data

Author, Year	Publication Type	Use of Ultrasound	Physiotherapist involvement	Mediastinal position reported	Diagnosis/etiology of opaque hemithorax
Vaidya et al. 2017 [2]	Observational	Yes	No	Yes	Multiple (n = 30)
Bharty et al. 2013 [3]	Observational	No	No	Yes	Multiple (n = 104)
Yu et al. 1993 [4]	Observational	Yes	No	Yes	Multiple (n = 50)
Wu et al. 1989 [5]	Observational	Yes	No	Yes	Multiple (n = 65)
Wipprecht et al. 2018 [6]	Case Report	Yes	No	Ipsilateral	Haemothorax
Zhu et al. 2018 [7]	Case Report	No	No	Ipsilateral	Bronchial intubation
Mahmoud et al. 2017 [8]	Case Report	No	No	Not Reported	Pancreaticopleural fistula
Marchiori et al. 2017 [9]	Case Report	No	No	Ipsilateral	Endobronchial tumour
Iqbal et al. 2017 [10]	Case Report	No	No	Contralateral	Pancreatic pseudocyst
Porter et al. 2017 [11]	Case Report	No	No	Contralateral	Hydrothorax
Wulff et al. 2017 [12]	Case Report	No	No	Not Reported	Extrabronchial - haematoma
Henderson et al. 2017 [13]	Case Report	No	No	Not Reported	Perforated diaphragm
Tandon et al. 2017 [14]	Case Report	No	No	Not Reported	Foreign body
Doo et al. 2017 [15]	Case Report	No	No	Contralateral	Chylothorax
Young et al. 2017 [16]	Case Report	No	No	Not Reported	Endobronchial tumour
Kukkadapu et al. 2017 [17]	Case Report	No	No	Contralateral	Extrabronchial tumour
Singh et al. 2017 [18]	Case Report	No	No	Not Reported	Urinothorax
Alwassia et al. 2017 [19]	Case Report	No	No	Not Reported	Endobroncial sarcoma
Rhanim et al. 2016 [20]	Case Report	No	No	Not Reported	Haemothorax
Sharma et al. 2016 [21]	Case Report	No	No	Central	Hydatid cyst
Phuangchoei et al. 2016 [22]	Case Report	No	No	Contralateral	Extrabronchial sarcoma
Sen et al. 2016 [23]	Case Report	No	No	Not Reported	Haemothorax
Villaneva et al. 2015 [24]	Case Report	No	No	Contralateral	Empyema
Leech et al. 2015 [25]	Case Report	Yes	Yes	Ipsilateral	Pleural effusion
Kumar et al. 2015 [26]	Case Report	No	No	Ipsilateral	Sputum plug
Frizzell et al. 2015 [27]	Case Report	Yes	No	Central	Haemothorax
McCambridge et al. 2015 [28]	Case Report	No	No	Not Reported	Chylothorax
Lau et al. 2014 [29]	Case Report	No	No	Ipsilateral	Endobronchial tumour
Salem et al. 2014 [30]	Case Report	No	No	Contralateral	Extrabronchial histiocytoma
Chawla et al. 2014 [31]	Case Report	No	No	Ipsilateral	Hypoplasia
Esmadi et al. 2013 [9] [32]	Case Report	Yes	No	Central	Empyema
Tack et al. 2012 [33]	Case Report	No	No	Central	CSF
Sharma et al. 2012 [34]	Case Report	No	No	Central	Sputum plug
Peterzan et al. 2012 [35]	Case Report	No	No	Contralateral	Haemothorax - endometriosis
Lonial et al. 2012 [36]	Case Report	No	No	Not Reported	Foreign body
Toney et al. 2011 [37]	Case Report	No	No	Not Reported	Pleural fibrous tumour
Drury et al. 2010 [38]	Case Report	No	No	Ipsilateral	Endobronchial tumour
Girdhar et al. 2010 [39]	Case Report	No	No	Contralateral	Extrabronchial sarcoma
Oikonomou et al. 2010 [40]	Case Report	No	No	Contralateral	Pleural lymphoma
Alzand et al. 2010 [41]	Case Report	No	No	Contralateral	Aortic dissection
Zaky et al. 2009 [42]	Case Report	No	No	Ipsilateral	Sputum plug 2 to phrenic palsy
Adeniji et al. 2009 [43]	Case Report	No	No	Contralateral	Lymphoma
Godoy et al. 2008 [44]	Case Report	No	No	Not Reported	Endobronchial tumour
Peek et al. 2008 [45]	Case Report	No	No	Central	Haemothorax
Baker et al. 2008 [46]	Case Report	No	No	Contralateral	Empyema
De Almeida et al. 2008 [47]	Case Report	No	No	Not Reported	Extrabronchial tumour
Demir et al. 2006 [48]	Case Report	No	No	Not Reported	Bronchostenosis
Walker et al. 2005 [49]	Case Report	No	No	Contralateral	Extrabronchial tumour
Fuchs et al. 2005 [50]	Case Report	No	No	Ipsilateral	Extrabronchial sarcoma
Lee et al. 2005 [51]	Case Report	No	No	Central	Mesothelioma
Altun et al. 2003 [52]	Case Report	No	No	Ipsilateral	Sputum or bronchial intubation
Barker et al. 2003 [53]	Case Report	No	Yes	Ipsilateral	Haemoptysis - plug
Campman et al. 2000 [54]	Case Report	No	No	Not Reported	Haemothorax
Higgins et al. 1994 [55]	Case Report	No	No	Not Reported	Lymphoma
Levy et al. 1993 [56]	Case Report	No	No	Central	Pulmonary oedema
Rommes et al. 1992 [57]	Case Report	No	No	Central	Haemoptysis - plug
Le Delfa et al. 1987 [58]	Case Report	No	No	Ipsilateral	Agenesis
Bedi et al. 1985 [59]	Case Series	Yes	No	Not Reported	Multiple (n = 10)

The various causes of an opaque hemithorax were collated from all fifty eight included studies and divided into 16 categories (Table 2): Pleural effusion, empyema, haemothorax, chylothorax, consolidation, mucus plugging, foreign body occlusion, endobronchial mass, extrabronchial mass, diaphragmatic compromise, cyst, main bronchus intubation, pneumonectomy, agenesis, tuberculosis and bronchial stenosis.

Table 2

Potential causes of an opaque hemithorax

Pleural Effusion	Chylothorax
Empyema	Mucus Plugging
Tuberculosis	Cyst
Consolidation	Main bronchus intubation
Endobronchial mass	Pneumonectomy
Extrabronchial mass	Diaphragmatic compromise
Haemothorax	Foreign body occlusion
Agenesis (inc. hypoplasia &aplasia)	Bronchial stenosis

Most common causes of an opaque hemithorax according to the four included observational studies were pleural effusion (with or without underlying malignancy/mass), empyema, tuberculosis, consolidation/atelectasis, extrabronchial mass and endobronchial mass (Table 2).

The four observational studies [2 –5] also reported on the position of the mediastinum (and trachea) on CXR to differentially diagnose the cause of an opaque hemithorax based on the volume of the affected hemithorax (Table 1). There are typically three variations reported:

Increased hemithorax volume causing a shift of the mediastinum towards the unaffected side (contralateral). i.e. typically, pleural effusions or thoracic mass.

Reduced hemithorax volume causing a shift of the mediastinum towards to affected side (ipsilateral). i.e. typically, agenesis, pneumonectomy or atelectasis.

Unchanged hemithorax volume with no mediastinal shift (central). i.e. typically, consolidation.

Of the 249 subjects in the four observational studies, 199 had a pleural effusion (with or without another pathology) contributing to the opaque hemithorax. Traditionally a moderate pleural effusion does not cause a mediastinal shift (trachea remains central) or if of sufficient size, a contralateral shift. As can be seen in (Table 3) this method of differential diagnosis has a questionable degree of accuracy. When the data from the 4 observational studies were combined for the subjects with a pleural effusion, 46% had a contralateral shift and 35% had no shift (central) as expected. However, the remaining 19% (38/199) had an ipsilateral shift which contradicts the previously described expected presentation.

Table 3

Mediastinum (shift) position in patients with pleural effusion

	Ipsilateral	Central	Contralateral
Vaidya et al., 2017 n = 30	11 (37%)	1 (3%)	18 (60%)
Bharty et al., 2013 n = 74	14 (19%)	20 (27%)	40 (54%)
Yu et al., 1993 n = 41	8 (20%)	15 (36%)	18 (44%)
Wu et al., 1989 n = 54	5 (9%)	33 (61%)	16 (30%)
Total n = 199	38 (19%)	69 (35%)	92 (46%)

When the same data is split into pleural effusion alone and pleural effusion with an associated malignancy/mass, the percentages begin to diverge further (Table 4). With a pleural effusion alone, the combined ipsilateral presentation of 19% reduces to 9%, whereas when a pleural effusion with an associated malignancy/mass the ipsilateral presentation increases to 30%.

Table 4

Difference between the mediastinum (trachea) position in patients with pleural effusions vs. pleural effusions with mass

	Ipsilateral	Central	Contralateral
Total n = 199	38 (19%)	69 (35%)	92 (46%)
Pleural Effusion only n = 101	9 (9%)	41 (41%)	51 (50%)
Pleural Effusion with mass n = 98	29 (30%)	27 (28%)	41 (42%)

The underlying diagnosis/etiology and mediastinal position, when reported, for the individual case reports can also be found in (Table 1).

Wu et al. (1989) report that they found no correlation between the CXR volume pattern (mediastinal shift) and the underlying pathological cause. Yu et al. (1993), a follow up study to Wu et al. (1989) by the same team, also states that observing volume changes is not a satisfactory method of CXR diagnostic capabilities in opaque hemithorax. In their findings, when a pleural effusion is associated with a malignancy/mass the volume, and resulting mediastinal shift, can increase, decrease or remain unchanged.

Eight studies included the use of TUS to differentiate the cause of an opaque hemithorax and included four case reports [6 , 32], one case series [59] along with three observational studies [2 , 4–5] (Table 1). Studies using TUS to differentiate an opaque hemithorax ranged in date from as early as 1985 [59] to 2018 [6]. The three observational studies included one paper where CXR is compared directly to TUS in 65 patients [5]. The other two compare CXR and TUS against the “gold standard” of computed tomography (CT) in a combined total of 80 patients [2, 4]. Only Yu et al. (1993) reported any results regarding the sensitivity or specificity of TUS when compared against the reference standard of CT.

Only two studies reported the involvement of physiotherapy, once for sputum plug removal [53] and once when the physiotherapist identified the cause of the opaque hemithorax themselves using TUS [25].

4 Discussion

A wide range of pathologies may present as an opaque hemithorax on CXR making differential diagnosis difficult. Within this review those pathologies have been divided into sixteen different categories (Table 2). Surprisingly, fifty four of the fifty-eight (93%) published works on opaque hemithorax are single patient case reports or case series. This introduces publication bias as only unusual or rare case presentations would be published, thus skewing the reported population away from the most common presentations. The four observational studies [2 –5] perhaps report on more typical populations due to larger sample sizes and therefore offer slightly better heterogeneity. As mentioned previously, two of the observational studies were published over 25 years ago by the same team in Taiwan [4, 5], while the two more recent studies take data from an Indian (Indian subcontinent) population [2, 3]. So, with most publications in this review being subject to publication bias and the larger observational studies taking subjects from only two countries, the application of these findings to other subject populations should be done with caution.

According to Wu et al. (1989), the reason for an absent correlation between the mediastinal position on CXR and the underlying cause is because an opaque hemithorax often results from a combination of pathologies. The same team’s subsequent publication, Yu et al. (1993), explains that it is not satisfactory enough to just observe changes in lung volume and its effect on neighbouring soft tissue structures to diagnose the cause of an opaque hemithorax. The CXR converts a 3-dementional structure into a 2-dimentional image which allows pathologies from a pleural, parenchymal, mediastinal or diaphragmatic origin to not only look similar on CXR but also underestimate the degree to which they may interact and impact on each other. The results presented in Tables 3 and 4 show that within this collection of papers the premise that a contralateral shift implies pleural effusion and an ipsilateral shift implies collapse is incorrect. Even when a single pathological process is involved, i.e. pleural effusion only, the expected contralateral shift is only seen 50% of the time and no shift 41% of the time (Table 4). Nine percent of the time a pleural effusion large enough to cause an opaque hemithorax results in an ipsilateral shift making this method of differential diagnosis incorrect in nearly 1 in 10 patients. The inaccuracy of using mediastinal shift on CXR only worsens when a second pathology is introduced into the clinical picture. When a pleural effusion is associated with a malignancy or tumour mass a contralateral shift is seen less often, only 42% of cases. Interestingly the remaining cases are almost evenly split between central (28%) and an ipsilateral shift (30%). This makes the position of the mediastinum even more unreliable as a method of differentially diagnosing an opaque hemithorax. This difference is made worse by the fact that CXR cannot easily distinguish between a pleural effusion on its own and one associated with a malignancy or tumour mass.

Within the individual case reports, when mediastinal position is reported, this unreliable pattern continues. It would appear too simplistic that a pleural effusion large enough to cause an opaque hemithorax always results in a contralateral shift and an ipsilateral shift rules out a pleural effusion.

It seems reasonable to explore ways of differentially diagnosing the underlying cause of an opaque hemithorax when CXR is unclear. In the eight papers that use TUS, all of them advocate the use of TUS as a useful, non-invasive tool to examine the cause of an opaque hemithorax prior to any potential request for CT. Wu et al. (1989) and Yu et al. (1993) both advocate the use of TUS as most causes of an opaque hemithorax produce an “acoustic window” allowing improved sonographic images. This can either be due to a loss of aeration of the lung parenchyma (consolidation/atelectasis), pleural pathology (pleural effusion) or various thoracic tumours. It is suggested that if an obvious pathology causing the opaque hemithorax is in doubt or complex pathology is suspected following CXR, then TUS should be considered. Esmadi et al. (2013) also support the use of TUS as it helps identify the nature of the lung pathology. Taking this concept further, Bedi et al. (1985) state that when TUS is used as the first method of imaging, it is usually not necessary to perform other examinations. It must be stated, that however useful TUS may prove, if there is any doubt regarding the cause of an opaque hemithorax then more advanced imaging, such as CT, should be requested.

According to this selection of studies physiotherapists appear to have a limited role in the management of opaque hemithorax. Only two studies report on the involvement of physiotherapy in the management of opaque hemithoracies. Barker et al. (2003) report on the use of physiotherapy to assist in the removal of endobronchial blood clots that had resulted in an opaque hemithorax with an ipsilateral shift. The second study by Leech et al. (2015) report on an opaque hemithorax, initially thought to be due to sputum retention, but then later confirmed as a pleural effusion identified through physiotherapy-performed TUS. These two studies hint at a more effective use of physiotherapy resources through the correct diagnosis of the opaque hemithorax using TUS. The TUS could be performed by a member of the medical team or alternatively the physiotherapist could perform it themselves one adequately trained. This could aid in the differential diagnosis of an opaque hemithorax and either more accurately identify patients amenable to physiotherapy treatment techniques or avoid unnecessary and ineffective physiotherapy interventions.

5 Conclusion

Numerous pathologies of the pleural, parenchymal, diaphragmatic and mediastinal origin can cause an opaque hemithorax on CXR making differential diagnosis difficult. Even when mediastinal shift is present it does not appear to be a reliable way to identify the underlying cause. Thoracic ultrasound has the potential to much more accurately differentiate between pathologies. This would assist physiotherapists to identify patients amenable to physiotherapy treatment techniques.

Author contributions

SH developed and performed the search. SH and LH both shortlisted and performed the data extraction. SH wrote the manuscript, LH provided feedback on manuscript structure and content.

Conflict of interest

None to report.

Footnotes

Acknowledgments

Thanks go to the Physiotherapy department, Critical Care teams and the Library services at Blackpool Teaching Hospitals NHS Foundation Trust.

References

Winkler

, Touw

, van de Ven

, Twisk

, Tuinman

. Diagnostic accuracy of chest radiograph, and when concomitantly studied lung ultrasound, in critically ill patients with respiratory symptoms: A Systematic review and mata-analysis. Critical Care Medicine. 2018;46(7):e707–e14. https://doi.org/10.1097/CCM.0000000000003129

Vaidya

, Vohra

, Ghugare

. Opaque hemithorax: Clinical, histological and radiological assessment of 30 cases at a tertiary care hospital – a preliminary study. West African Journal of Radiology. 2017;24:34–7. https://doi.org/10.4103/1115-3474.198090

Bharty

, Prakash

, Bhatnagar

, Agarwal

. Opaque hemithorax: Re-visiting the causes. Internet Journal of Pulmonary Medicine. 2013;14(1).

C-J

, Yang

P-C

, Wu

H-D

, Chang

D-B

, Kuo

S-H

, Luh

K-T

. Ultrasound study in unilateral hemithorax opacification: Image comparison with computed tomography. American Review of Respiratory Disease. 1993;147(2):430–4. https://doi.org/10.1164/ajrccm/147.2.430

, Yang

, Kuo

, Luh

. Ultrasonography in complete chest X-ray opacification of hemithorax. Journal of the Formosan Medical Association. 1989;88(7):694–9.

Wipprecht

, Rahman

, Sohail

, Mushtaq

, Rehman

. Spontaneous tension hemothorax: Previously undescribed cause of shock diagnosed by ultrasonography. Critical Care Medicine. 2018;46:521. https://doi.org/10.1097/01.ccm.0000529080.11085.cc

Zhu

, Weiner

, Nadler

. Radiographic hemithorax white-out following percutaneous nephrolithotomy. Urology Case Reports. 2018;17:1–3. https://doi.org/10.1016/j.eucr.2017.12.002

Mahmoud

, Churrango

, Wassef

. A Case report of pancreaticopleural fistula that was treated conservatively. American Journal of Gastroenterology. 2017;112.

Marchiori

, Hochhegger

, Zanetti

. Opaque hemithorax. Jornal brasileiro de pneumologia: Publicacao oficial da Sociedade Brasileira de Pneumologia e Tisilogia . 2017;43(3):161. https://doi.org/10.1590/S1806-37562017000000024

10.

Iqbal

, Stadler

, Iqbal

. A rare case of ruptured mediastinal pancreatic pseudocyst. Chest. 2017;152(4).

11.

Porter

, Finley

, Millington

, Phillips

. Small cell lung cancer presenting as tension hydrothorax: A Case report. Chest. 2017;152(4).

12.

Wulff

, Chan Lee

, Ferrer

. An Unusual etiology of mediastinal mass: A Case report. Chest. 2017;152(4).

13.

Henderson

, Brigue

. Laparoscopy associated pneumohydrothorax: Recognising something is wrong. Anaesthesia. 2017;72:38.

14.

Tandon

, Balestra

, Aragaki

. Spud aspiration: Removal of a raw potato from the airway. American Journal of Respiratory and Critical Care Medicine. 2017;195.

15.

Doo

, Pillai

, Liu

, Lesko

, Lubinsky

, Smith

. Markedly delayed occurrence of chylothorax following thoracic surgery. American Journal of Respiratory and Critical Care Medicine. 2017;195.

16.

Young

, Arshad

, Adurty

. A Rare case of small cell lung cancer (SCLC) presenting as an endobronchial lesion. American Journal of Respiratory and Critical Care Medicine. 2017;195.

17.

Kukkadapu

, Gupta

, Wallace

, Forseen

, Keshavamurthy

. Primary germ cell tumor presenting as anterior mediastinal mass-A rare entity! American Journal of Respiratory and Critical Care Medicine. 2017;195.

18.

Singh

, Lakticova

, Agrawal

. Failure of occam’s razor: Obstructive urinothorax after a nephrostomy. American Journal of Respiratory and Critical Care Medicine. 2017;195.

19.

Alwassia

, Alshathri

, Khosla

, Spagnolo

. Pulmonary Kaposi sarcoma presenting as complete lung consolidation. BMJ Case Reports. . 2017:2017. https://doi.org/10.1136/bcr-2016-219048

20.

Rhanim

, Herrak

, Slimani

, Achachi

, El Ftouh

. A Rare cause of haemorrhagic pleurisy: Dissection of the aorta. Revue des maladies respiratoires. 2016;33(7):618–21. https://doi.org/10.1016/j.rmr.2015.11.012

21.

Sharma

, Kumar

, Jain

, Raghav

. Giant pulmonary hydatid cyst: An Unusual presentation. American Journal of Respiratory and Critical Care Medicine. 2016;194(8). https://doi.org/10.1164/rccm.201603-0479IM

22.

Phuangchoei

, Yuangtrakul

, Chuaychoo

, Akewanlop

, Ruangchira-Urai

. Extraskeletal ewing sarcoma presenting with pleural effusion: Case report. Respirology. 2016;21:141.

23.

Sen

, Palakuru

, Balachandran

. Pulmonary hemorrhage from stenotrophomonal pneumonia in leukemics. Chest. 2016;150(4). https://doi.org/10.1016/j.chest.2016.08.205

24.

Villanueva

, Milder

, Peeceeyen

. Massive tension pyothorax. Heart Lung and Circulation. 2015;24. https://doi.org/10.1016/j.hlc.2014.12.077

25.

Leech

, Bissett

, Kot

, Ntoumenopoulos

. Physiotherapist-initiated lung ultrasound to improve intensive care management of a deteriorating patient and prevent intubation: A Case report. Physiotherapy Theory and Practice. 2015;31(5):372–6. https://doi.org/10.3109/09593985.2014.1003629

26.

Kumar

, Poongadan

, Singh

. Allergic bronchopulmonary aspergillosis presenting as lobar or total lung collapse. Pneumonologia i Alergologia Polska. 2015;83(2):144–50. https://doi.org/10.5603/PiAP.2015.0023

27.

Frizzell

, Griffin

, Boivin

, Saeed

. A 73-Year-Old Man With Left Lung “White Out”. Chest. 2015;148(2):e38. https://doi.org/10.1378/chest.14-1621

28.

McCambridge

, Foley

, Escalante

. Chylothorax in adult patient with a mediastinal lymphangioma: A Successful non-surgical treatment. American Journal of Respiratory and Critical Care Medicine. 2015;191.

29.

Lau

K-K

, Fung

S-L

, Wong

C-F

. A Young man with a sudden ‘white out’ of right hemithorax on chest radiograph. QJM: Monthly Journal of the Association of Physicians. 2014;107(10):845–6. https://doi.org/10.1093/qjmed/hcs033

30.

Salem

, Khalife

, El Nounou

, El Naaj

, Faraj

, Shamseddine

, Mukherji

. Haydar A. Malignant fibrous histiocytoma presenting with complete opacification of the hemithorax: A Case report. International Journal of Surgery Case Reports. 2014;5(12):1162–3. https://doi.org/10.1016/j.ijscr.2014.11.006

31.

Chawla

, Das

, Madan

, Chawla

. Completely opaque hemithorax Lung. India. 2014;31(4):416–8. https://doi.org/10.4103/0970-2113.142095

32.

Esmadi

, Ahmad

, Lone

, Onofrio

, Brush

. Multiloculated pleural effusion detected by ultrasound only in a critically-ill patient. American Journal of Case Reports. 2013;14:63–6. https://doi.org/10.12659/AJCR.883816

33.

Tack

, Ganeshan

, Wide

, Stockton

. “White out”: A Rare cause. Thorax. 2012;67(8):757. https://doi.org/10.1136/thoraxjnl-2011-201409

34.

Sharma

, Heist

, Ferrell

. Treatment for ST-elevation myocardial infarction–bronchoscopy!. The American Journal of Emergency Medicine. 2012;30(8):1660. https://doi.org/10.1016/j.ajem.2011.08.018

35.

Peterzan

, Reynolds

, Dulay

, Wooldridge

. Thoracic endometriosis syndrome manifesting as atraumatic haemothorax causing difficult ventilation under general anaesthesia. BMJ Case Reports. 2012;2012. https://doi.org/10.1136/bcr-2012-007206

36.

Lonial

, Vyas

. An Unusual case of “adult-onset” asthma. Chest. 2012;142(4).

37.

Toney

, Khan

, Weller

. Giant solitary fibrous tumor of the pleura. American Journal of Respiratory and Critical Care Medicine. 2011;183(1).

38.

Drury

, Moro

, Cartwright

, Ali

, Nashef

. A Unilateral whiteout: When not to insert a chest drain. Journal of the Royal Society of Medicine. 2010;103(1):31–3. https://doi.org/10.1258/jrsm.2009.090204

39.

Girdhar

, Zaiden

. A 54-year-old man with right opaque hemithorax and worsening shortness of breath. Respiration; International Review of Thoracic Diseases. 2010;79(2):157–9. https://doi.org/10.1159/000235973

40.

Oikonomou

, Prassopoulos

, Giatromanolaki

, Margaritis

, Froudarakis

. Primary pleural lymphoma: Plaque-like thickening of the pleura. Japanese Journal of Radiology. 2010;28(1):62–5. https://doi.org/10.1007/s11604-009-0377-5

41.

Alzand

BSN

, Al-Haidari

AMH

. Unilateral lung whiteout: Beyond the standard differential diagnosis. Heart (British Cardiac Society). 2010;96(20):1632. https://doi.org/10.1136/hrt.2010.204693

42.

Zaky

, Seif

, Abd-Elsayed

, Bashour

. Recurrent lung collapse due to unidentified phrenic nerve injury after cardiac surgery. Minerva Anestesiologica. 2009;75(9):533–6.

43.

Adeniji

, Amer

, Bell

, Millar

. Pyothorax-associated lymphoma - The first reported case in the UK Journal of the Royal College of Physicians of Edinburgh. 2009;39(1):22–4.

44.

Godoy

, Vega

, Jorge

RGL

. Recurrent left lung atelectasis caused by an endobronchial metastasis of a colon cancer: Report of one case. Revista Medica De Chile. 2008;136(2):217–20.

45.

Peek

, Ibrahim

, Abunasra

, Waller

, Natarajan

. White-out from a Wii: Traumatic haemothorax sustained playing Nintendo Wii. Annals of the Royal College of Surgeons of England. 2008;90(6):W9.

46.

Baker

, Carlson

. Streptococcus acidominimus isolated from a multiloculated empyema in a critically ill adult man with pneumonia: Case report and review of literature. Heart and Lung: Journal of Acute and Critical Care. 2008;37(4):308–10. https://doi.org/10.1016/j.hrtlng.2007.08.002

47.

de Almeida

LFS

, Szarf

, Lederman

, de Franco

, de Oliveira

, Luiz

. Giant pulmonary hamartoma. Journal of Thoracic Imaging. 2008;23(3):188–90. https://doi.org/10.1097/RTI.0b013e3181654405

48.

Demir

, Olcmen

, Kara

, Dincer

. Delayed diagnosis of a complete bronchial rupture after blunt thoracic trauma. The Thoracic and Cardiovascular Surgeon. 2006;54(8):560–2. https://doi.org/10.1055/s-2006-924480

49.

Walker

, Suvarna

. Matthews case report: Pulmonary blastoma: Presentation of two atypical cases and review of the literature. The British Journal of Radiology. 2005;78(929):437–40. https://doi.org/10.1259/bjr/45172814

50.

Fuchs

, Wiest

, Hahn

, Rupprecht

. 69 year-old patient with opaque hemithorax on the right side. Der Internist. 2005;46(12):1389–93. https://doi.org/10.1007/s00108-005-1503-9

51.

Lee

DKC

, Sleat

GKJ

, Borade

. Lung whiteout with normal chest signs. QJM: Monthly Journal of the Association of Physicians. 2005;98(11):837. https://doi.org/10.1093/qjmed/hci131

52.

Altun

, Erdogan

. A Chest X-Ray Image: Total opacification of the hemithorax. Cardiology in Review. 2003;11(6):301–30. https://doi.org/10.1097/01.crd.0000089526.05199.04

53.

Barker

, Sahn

. Opacified hemithorax with ipsilateral mediastinal shift after transthoracic needle biopsy. Chest. 2003;124(6):2391–2.

54.

Campman

, Holmes

, Sokolove

, Romero

, Yost

, Lie

. Pulmonary arterial fibromuscular dysplasia: A Rare cause of fulminant lung hemorrhage. The American Journal of Forensic Medicine and Pathology. 2000;21(1):69–73.

55.

Higgins

, Shuttari

, Demmy

, Loy

, Calaluce

. Diffuse large cell lymphoma of the lung: An Unusual cause of complete opacification of the hemithorax. Southern Medical Journal. 1994;87(11):1183–118.

56.

Levy

, Tzabar

. Whiter than whiteout. Anaesthesia. 1993;48(1):91.

57.

Rommes

, Baur

HJCM

. The Opaque hemithorax: Fluid or collapse? Inappropriate insertion of a chest drain in a blunt thoracic trauma patient. Clinical Intensive Care. 1992;3(1):92–9.

58.

La Delfa

, McLean

, Hoffstein

. Asymptomatic opacity of the left hemithorax in an adult. Journal of the American Medical Association. 1987;257(2):225–7.

59.

Bedi

, Fagan

, Hayden

. The Opaque right hemithorax: Identifying the diaphragm with ultrasound. Texas Medicine. 1985;81(12):37–42.