Department of Chest Surgery, Japanese Red Cross Fukui Hospital, Fukui, Japan.
Department of Thoracic Surgery, Nagoya University Graduate School of Medicine, Nagoya, Japan.
J Thorac Cardiovasc Surg. 2021 Nov;162(5):1417-1423.e2. doi: 10.1016/j.jtcvs.2020.08.017. Epub 2020 Aug 12.
Remaining lung tissue after pulmonary resection can expand without decline in structural complexity and compensate for functional loss, showing morphological and functional reserves. However, the distribution of these reserves is unknown. This study examined the heterogeneity of morphological and functional reserves of the remaining lung tissue.
We retrospectively analyzed 53 donors who underwent right lower lobectomy for living-donor lobar lung transplantation. We examined morphometric changes in computed tomography images from 3 to 12 months after lobectomy. We assessed lung volume and structural complexity expressed as the fractal dimension. We also assessed effective lung volume (the volume of the lung with intermediate density) and volumetric fluctuation during respiration. Changes were compared between the right upper lobe, middle lobe, and left lung.
The expansion of lung tissue was greater in the middle lobe (130.9% ± 19.7%) than in the upper lobe (109.7% ± 9.2%; P < .001). The fractal dimension declined in the upper lobe (P < .001) but was maintained in the middle lobe (P = .39). The increase in effective lung volume was larger in the middle lobe (97.2 ± 73.5 mL) than in the upper lobe (62.7 ± 87.1 mL; P < .001), but not significantly different from that of the left lung (55.8 ± 186.3 mL; P = .052). A similar pattern was seen in respiratory fluctuation.
Morphological and functional changes in lung tissue remaining after pulmonary resection were heterogeneous. The right middle lobe demonstrated morphological and functional reserves after right lower lobectomy.
肺切除术后剩余的肺组织可以在不降低结构复杂性的情况下扩张，并补偿功能丧失，显示出形态和功能储备。然而，这些储备的分布情况尚不清楚。本研究旨在探讨剩余肺组织的形态和功能储备的异质性。
我们回顾性分析了 53 例因活体供肺叶移植而行右下肺叶切除术的供者。我们在术后 3 至 12 个月时对 CT 图像进行了形态学变化检查。我们评估了肺体积和结构复杂性，分别用分形维数表示。我们还评估了中间密度的有效肺体积（具有中间密度的肺体积）和呼吸时的体积波动。比较了右肺上叶、中叶和左肺之间的变化。
中叶的肺组织扩张程度大于上叶（130.9%±19.7%比 109.7%±9.2%；P<0.001）。上叶的分形维数下降（P<0.001），而中叶的分形维数保持不变（P=0.39）。中叶的有效肺体积增加量大于上叶（97.2±73.5 mL 比 62.7±87.1 mL；P<0.001），但与左肺无显著差异（55.8±186.3 mL；P=0.052）。呼吸波动也呈现出类似的模式。
肺切除术后剩余肺组织的形态和功能变化存在异质性。右中叶在右下肺叶切除术后具有形态和功能储备。
