The Morphological Alternation Of The Diaphragm In Patients With Chronic Obstructive Pulmonary Disease With Three-dimensional Reconstruction Of64-slice Spiral CT

Objective To study the morphological alternation of the diaphragm withthree-dimensional reconstruction in patients with chronic obstructive pulmonary disease(COPD), and to evaluate its correlation with the severity of the disease.Methods Subjects were consecutively recruited in ShangHai East Hospital of TongjiUniversity from July2010to April2011. They were divided into COPD (30males) andcontrol (20males), including mild (n=10), moderate (n=10), severe/very severe (n=10), theage of them ranged from50to80years old. Those who met the enrollment criteria wereasked to take pulmonary function test. Each subject underwent CT scanning in residualvolume (RV) and total lung capacity (TLC) phases. The imaging of CT scanning was usedto reconstruct three-dimensional diaphragm with the special computer software. Weobserved the length of total diaphragm (Ldi), including the part of the zone apposition (Lap)and part of the dome (Ldo) under coronal (C) and sagittal (S). The surface area of thediaphragm (Adi), surface area (Aap) of the zone of apposition and surface area (Ado) of thedome were observed as well. In addition, the relationship between morphological indexs andpulmonary function were evaluated.Results In residual volume phase, the length of total diaphragm in sagittal (S-Ldi)and the part of the zone apposition in sagittal (S-Lap) in COPD was (23.3±2.9) cm,(5.4±1.9)cm respectively, which was significantly lower than that of control group (31.1±4.3) cm and(12.7±2.0) cm, the difference between both groups was statistically significant (t=4.12,6.96, respectively. all P<0.05). The reduction is more obvious in Sagittal than Coronal, and thereduction of S-Lap is about94%in the one of S-Ldi; In residual volume phase, the surfacearea of the diaphragm (Adi), surface area of the zone of apposition (Aap) in COPD was(571±119) cm~2,(270±99) cm~2respectively, which was significantly lower than that of controlgroup (811±95) cm~2and (471±61) cm~2, the difference was statistically significant(t=4.06,4.33, respectively. all P<0.05). Aap decreased more significantly, and accounted for83%inthe reduction of Adi. There was a significant positive correlation between Aap and S-Lapwith pulmonary function (r=0.577~0.787, all P<0.05), especially in Aap (r=0.787). In TLCphase, there was a significant lower only in C-Ldi, C-Lap (t=3.08,2.80, respectively. allP<0.05).Conclusions The diaphragmatic length and surface area decreased in the patients withCOPD, which is more pronounced in the part of the zone of apposition and is occurred duringRV phase. The dimension of the zone of apposition could be a parameter to reflect theseverity of the disease.