【Objective】To analyze the morphological features of peripheral pulmonary carcinoma by using the postprocessing technique of MSCT (orthogonal planar reconstruction (OPR) combing MIP). 【Methods】 75 patients (male: female=36: 39; mean age: 60 years) with pathologically proved peripheral pulmonary carcinoma were investigated retrospectively and underwent CT examination before surgery. The morphologic features (margin

lobulation

vascular convergence

pleural indentation

and spiculation) and the diagnosis of each nodule which based on traverse

coronal

saggital and OPR combing 5mmMIP CT images were recorded and compared

respectively. 【Results】 OPR (parallel to the pulmonary bronchovascular bundle) with 5mm MIP could significantly demonstrated more vascular convergence sign (N5mmMIP: Naxial= 27(36%): 13(17%)

P≤0.007) and pleural indentation (N5mmMIP: Naxial= 57(76%): 48(64%)

P≤0.004); However

the spiculation sign was less found (N5mmMIP: Naxial=24: 38

P≤0.003) in OPR (parallel to the pulmonary bronchovascular bundle) combing 5mmMIP. Besides

for nodule margin

lobulation

spiculation and pleural indentation

there were no significant differences were found among OPR (plumb to the pulmonary bronchovascular bundle)

traverse

coronal and saggital CT images. Further

comprehensively analysis of the nodules in different imaging sections

compared with traverse CT images

could significantly improve our diagnosis (52%-71%

P<0.05). 【Conclusion】 OPR (parallel to the pulmonary bronchovascular bundle) 5mmMIP could significantly show more vascular convergences and pleural indentations which could significantly improve our diagnosis for peripheral pulmonary nodule.