Pulmonary veins variations with potential impact in thoracic surgery: a computed-tomography-based atlas

Anatomical distribution and clinical significance of translobar bronchi, arteries, and veins hidden in the interlobar fissure

Background

The interlobar bronchovascular structures hidden in the incomplete interlobar fissures (IFs) are often inadvertently transected during pulmonary resections, which could inevitably lead to accidental injury and potentially compromise the function of the preserved area. A thorough examination of the anatomical distribution of translobar bronchi, arteries, and veins holds significant clinical importance.

Methods

Three-dimensional computed tomography bronchography and angiography (3D-CTBA) data from patients who underwent pulmonary resection between December 2018 and November 2019 were retrospectively analyzed. The translobar bronchi, arteries, and veins were categorized based on their origin and distribution. Surgical results of patients who underwent surgery involving translobar structures were further reviewed.

Results

Among the 310 enrolled patients, incomplete IFs (IIFs) were most frequently observed in horizontal fissures (68.7%), followed by right upper oblique fissures (42.3%), left lower oblique fissures (32.6%), left upper oblique fissures (12.9%), and right lower oblique fissures (11.0%). The incidence of bronchovascular structures was significantly higher in IIFs than in complete IFs (CIFs; 85.5% vs. 5.2%, χ2=1,021.1, P<0.001). A total of three subtypes of translobar bronchi, five subtypes of translobar arteries, and 14 subtypes of translobar veins were identified. Primary subtypes of translobar arteries (frequency >5%) included the left A4/5 (18.7%) that branched from A7/8/7+8 and the common trunk of right Asc.A2+A6 (6.1%). Primary subtypes of translobar veins (frequency >5%) included the right V2 draining into inferior pulmonary vein (IPV) (5.8%), the interlobar V3b (58.4%) within horizontal fissures, the right V4/5 draining into V2/3 (26.1%), the left V4/5 draining into IPV (7.4%), the right V6 draining into V2 (38.4%), and the common trunk of left IPV and superior pulmonary vein (SPV; 9.4%). Moreover, 12.0% of translobar arteries and 75.0% of translobar veins were mistransected during anatomical pulmonary resection, resulting in gas-exchanging dysfunction in the preserved territory.

Conclusions

Translobar bronchovascular structures exhibited a high incidence and were more commonly present in IIFs. Surgeons should pay increased attention to these structures to prevent accidental injuries during anatomical pulmonary resection.

Right middle pulmonary vein classification by 3D-CT reconstruction and its clinical significance

Background

A profound understanding of the type of right middle lobe (RML) vein return is crucial for thoracic surgeons to ensure safe anatomic lung resection. In this study, the type of venous return in the RML and its clinical significance were analyzed using the 3D computed tomography (3D-CT) reconstruction technique.

Methods

This retrospective study analyzed the patients who underwent anatomical lobectomy or anatomical lung segment resection with preoperative 3D-CT reconstruction at the Department of Thoracic Oncology Surgery, Fujian Cancer Hospital from January 2020 to October 2022. The exclusion criteria were as follows: (I) blurred CT images and inadequate IQQA 3D reconstruction for clear visualization of bronchial and vascular subsegmental branches; (II) patients with a previous history of right middle lobectomy; (III) incomplete medical records.

Results

This study included 608 eligible cases, 245 males (40.30%) and 363 females (59.70%), with an average age of 58.61 years. We identified four major types of RML venous return, including 407 cases (66.94%) of central vein type, 123 cases (20.23%) of isolated vein type, 11 cases (1.81%) of basal vein type, and 67 cases (11.02%) of combined vein type. Furthermore, the central venous type comprised four subtypes: 191 cases (27.3%) had one branch, 165 cases (27.14%) had two branches, 43 cases (7.07%) had three branches, and 8 cases (1.32%) had more than three branches. The combined venous type includes four subtypes: combination type A (n=37 cases, 6.09%), combination type B (n=7 cases, 1.15%), combination type C (n=21 cases, 3.45%), and combination type D (n=2 cases, 0.33%).

Conclusions

Based on 3D-CT reconstruction, numerous types of venous return in the RML were found, highlighting the significance of 3D-CT reconstruction for thoracic surgeons. It plays a crucial role in understanding the type of RML venous return prior to surgery, providing invaluable information to ensure surgical safety and success.

Left common pulmonary venous trunk-better be careful than sorry

Pulmonary vein abnormalities are very commonly encountered in general thoracic surgical practice. While performing a lobectomy, ideally all the pulmonary veins should be identified before ligating the corresponding vein. Failing to recognize a common pulmonary vein may lead to an unwarranted pneumonectomy which may end up morbid for the patient. In this report, we present a patient with left lower lobe bronchiectasis who underwent a left lower lobectomy and was identified to have a common left pulmonary venous trunk intra-operatively.

VATS right posterior segmentectomy with anomalous bronchi and pulmonary vessels: a case report and literature review

Background

Anatomic variation may increase the difficulty and risk of anatomic segmentectomy. The preoperative three-dimensional computed tomography bronchography and angiography (3D-CTBA) can provide a detailed model of the segmental structure, and contribute to precise and safe segmentectomy.

Case presentation

This is a case of anomalous bronchi and pulmonary vessels in the right upper posterior segment (RS²). Under the guidance of 3D-CTBA, anatomic RS² segmentectomy was performed accurately and safely. The postoperative condition was uneventful.

Conclusions

This rare case highlights the importance of 3D-CTBA to guild accurate segmentectomy with anatomic variation.

[Translobar Phenomenon of Pulmonary Veins and Its Clinical Significance in Lobectomy]

背景与目的

肺叶切除术是早期肺癌的主要治疗方式，然而肺部解剖变异繁多，尤其是部分肺静脉会脱离正常解剖位置，甚至跨越肺叶边界进入相邻肺叶，这增加了手术的难度和风险。本研究旨在全面分析肺跨叶静脉的类型和发生频率，并进一步探究其在肺叶切除术中的临床意义。

方法

纳入南京医科大学第一附属医院2018年12月-2019年11月期间行肺部手术的患者916例，筛选出术前行胸部增强计算机断层扫描（computed tomography, CT）检查的病例310例，应用这些患者的胸部增强CT和三维CT支气管血管成像（three-dimensional computed tomography bronchography and angiography, 3D-CTBA）对跨叶静脉的类型及频率进行分析。进一步从916例手术病例中筛选出行肺叶切除术且手术区域涉及到跨叶静脉的病例共48例（切断组36例，保留组12例），通过手术录像观察两种不同的处理方式对余肺叶的影响。

结果

共发现26种肺跨叶静脉模式，总发生率为82.26%，右肺远大于左肺（80.65% vs 11.94%）。右肺中主要类型（频率 > 5%）包括：中间支气管后方汇入下肺静脉的VX2（5.48%）、汇集上、下叶静脉属支的叶间静脉V³b（58.39%）、水平裂内汇入V²（13.23%）或V³（12.58%）的VX⁴、中叶支气管下方汇入左心房的VX⁴（8.71%）或VX⁵（7.42%）、肺裂内汇入V²的VX⁶（29.68%）；左肺中主要类型为整支上肺静脉汇入下肺静脉形成共干的左肺静脉（9.36%），其中共干长度 > 1 cm的占4.84%。观察手术录像发现：与保留组相比，切断组中患者其余肺叶的血液循环功能受到影响（表现为受影响区域停止通气后长时间无法萎陷），术后咯血（13.89% vs 0.00%）和肺漏气（19.44% vs 8.33%）发生率增加，术后住院时间[(4.72±1.86) d vs (3.92±1.62) d]较长，术后3 d引流量[(705.42±265.02) mL vs (604.92±229.64) mL]较多，但差异无统计学意义（P > 0.05）。

结论

肺静脉跨叶现象种类繁多，且部分类型发生率较高。然而大部分跨叶静脉在手术中被忽视，这可能对手术安全和患者术后恢复产生不利影响。

Detection of circulatory disturbance after pulmonary vein division during a living donor lobectomy

Indocyanine green (ICG) is widely used during thoracic surgery to enhance visualization, allowing assessment of the intersegmental plane based on intrapulmonary blood flow (Travis et al. in Ann Thorac Surg 108(2):363-369, 2019; Seshiru et al. in Gen Thorac Cardiovasc Surg 66(2):81-90, 2018). Using ICG to detect blood flow disruption after lung resection, however, has not been addressed. We therefore report a case in which the left lingular pulmonary vein was incidentally divided during left lower lobectomy in a living-lung donor. Intraoperative ICG-enhanced near-infrared fluoroscopic imaging to assess intrapulmonary blood flow detected the problem. We thus avoided potential postoperative residual lung complications in this patient.