Phenotyping emphysema and airways disease: Clinical value of quantitative radiological techniques

Table 2 Treatment of chronic obstructive pulmonary disease as defined by computed tomography phenotypes

CT phenotype	CT defining features	Clinical features	Findings	Treatments	Ref.
Emphysema	↓ Perc15 Emphysema Centrilobular Panlobular Paraseptal Bullous	Health status	↓ BMI[2] ↑ SGRQ + MRC[7]	Rehabilitation Nutritional support Palliative care	GOLD 2016[5]
		Exercise tolerance	↓ 6MWD[2] ↓ pO2↓ pCO2[3]	Rehabilitation Maintenance of physical activity Oxygen	GOLD 2016[5]
		Lung function	↑ TLC ↓ KCO ↓ FEV1/FVC	LAMA/LABA LVRS/BVLS Transplant Bullectomy[11] LVRS[11]	GOLD 2016[5] NICE 2010[11]
		Symptoms	↑ Hb[3] No significant response to ICS[8]	Theophylline Rehabilitation typically MRC > 3	GOLD 2016[5] NICE 2010[11]
Airways disease		Exacerbation frequency/ severity	↑ Exacerbations hospital admissions[7]	LABA/phosphodiesterase-4 inhibitor LAMA/phosphodiesterase-4 inhibitor Mucolytics Add in ICS Prophylactic antibiotics	GOLD 2016[5] NICE 2010[11] Brown et al[12], 2007 Fabbri et al[13], 2009 Calverley et al[14], 2009 Herath et al[15], 2013
	Lower wall area/body Surface area ratio (WA/BSA) Lower luminal area/BSA Higher %WA	Symptoms	Significant response to ICS+ Significantly higher % of sputum eosinophils[8] Peribronchial thickening[10] Air trapping	Physiotherapy and active breathing techniques Mucolytics Roflumilast Bronchodilators	NICE 2010[11]

6MWD: 6 minute walk distance; CT: Computed tomography; ICS: Inhaled corticosteroid; FEV1/FVC: Forced expiratory volume in 1 second/forced vital capacity; TLC: Total lung capacity; HU: Hounsfield units; SGRQ: St georges respiratory questionnaire; MRC: Medical reseach council; HRCT: High resolution computed tomography; Perc15: 15^th percentile point; KCO: Gas transfer co-efficient; LVRS: Lung volume reduction surgery; LAMA: Long acting muscarinic antagonist.