Use of three-dimensional computed tomographic angiography of pulmonary vessels for lung resections

[Usefulness of Delay Time Setting in Computed Tomography Pulmonary Angiography]

PURPOSE

During computed tomography pulmonary angiography (CTPA), a decrease in the CT value of the pulmonary artery may be observed due to poor contrast enhancement, even though the imaging is performed at the optimum timing while continuously injecting a contrast medium. This study focused on the increase in blood flow in the superior and inferior vena cava during inspiration that affects the decrease in the CT value of the pulmonary artery and investigated a radiography method in which a delay time was set after inspiration in clinical cases.

METHODS

A total of 50 patients who underwent CTPA for suspected pulmonary thromboembolism were included. Using the bolus tracking method, we monitored the pulmonary arteries before and after inspiration, and investigated the CT value changes.

RESULTS

A decrease in the CT value of the pulmonary artery after inspiration was observed in approximately 30% of cases. By setting the delay time, the contrast enhancement effect before and after inspiration became equivalent.

CONCLUSION

As a result of this study, avoiding a decrease in the CT value of the pulmonary artery is possible by setting a delay time after inspiration, which is considered useful during CTPA.

Robotic Right Lower Lobectomy in a Patient With V2 and V4+5 Pulmonary Vein Variation Merging Into the Lower Pulmonary Vein: A Case Report

Several variations of pulmonary vein (PV) branching patterns exist. Since robot-assisted thoracoscopic surgery (RATS) is performed with magnified vision, it is crucial to carefully identify the running pattern of blood vessels before and during surgery. We present a case of a 77-year-old male patient with right lower lobe lung cancer. Right lower lobectomy via RATS was scheduled. Chest CT before surgery confirmed that the middle lobe PV (V4+5) merged with the inferior PV. Three-dimensional multidetector CT (3D-MDCT) subsequently confirmed that not only V4+5 but also the posterior segmental vein of the upper lobe (V2) merged with the inferior PV. We should have taped the lower lobe PV only, but we also taped the V2 and the middle lobe vein. However, since the oblique fissure was separated before cutting the taped blood vessel, the cutting of the blood vessel to be preserved was avoided. Surgeons should have a detailed understanding of the running patterns of pulmonary blood vessels before surgery to perform the procedure safely. Preoperative 3D-MDCT is useful for identifying the running pattern of blood vessels. An abnormality involving V2 and V4+5 merging into the inferior PV can also occur; hence, during right lower lobe resection, by dividing the lower lobe PV after the oblique fissure division, the surgeon can avoid unexpected transection of anomalous PVs that should be preserved.

An analysis of the left top pulmonary vein and comparison with the right top pulmonary vein for lung resection by three-dimensional CT angiography and thin-section images

PURPOSE

The right top pulmonary vein (RTPV) is defined as an anomalous branch of the right superior PV (SPV) draining into the PV or left atrium (LA). Several previous reports have described the RTPV, but only a few have mentioned the left top PV (LTPV). The present study aimed to evaluate the branching patterns of the RTPV and LTPV using thin-section CT images and three-dimensional CT angiography (3D-CTA).

MATERIALS AND METHODS

This study included 1437 consecutive patients for evaluation of the right side and 1454 consecutive patients for the left side who were suspected of lung cancer and underwent CTA. We assessed the presence of each RTPV and LTPV and their branching patterns on the CTA images. When the RTPV or LTPV was identified, the maximum short-axis diameter was measured.

RESULTS

RTPV was found in 9.1% (131/1437), whereas LTPV was found in 2.9% (42/1454) of the patients. RTPV was also observed in 17.1% (7/41) of LTPV cases, except for one case in which the right side could not be evaluated. The most common RTPV inflow site was the right inferior PV (IPV) in 64.9% (85/131) of the patients, whereas that of the LTPV was the left IPV in 100.0% (42/42) of the patients. The mean diameter of the RTPV and LTPV was 3.3 mm (range, 1.3-7.5 mm) and 2.4 mm (range, 0.9-6.3 mm), respectively (P < 0.01).

CONCLUSION

The top PV branching pattern variations can be evaluated using thin-section CT and 3D-CTA images. RTPV is not a rare finding, and LTPV should also be identified in lung cancer cases scheduled for resection.

Application of three-dimensional computed tomography imaging and reconstructive techniques in lung surgery: A mini-review

Background

Pulmonary surgery is an innovative discipline with increasing demands for minimally invasive techniques in complicated anatomical resections, warranting adequate preoperative imaging of relevant surgical anatomy to ensure safe and radical resection of target lesions. Over the recent years, the emergence of imaging techniques enabling three-dimensional reconstruction has exerted promising influence on pulmonary surgery, facilitating optimal surgical planning and easier identification of the spatial relationship between bronchovascular structures in the individual patient and aiding the safe resection of target pulmonary lesions. The goal of this mini-review is to provide an overview of three-dimensional computed tomography imaging within pulmonary surgery.

Methods

The authors performed a targeted qualitative review of the literature to identify current trends and to provide better understanding of three-dimensional reconstruction within the boundaries of pulmonary surgery.

Results

Three-dimensional reconstructive techniques can be used for resectability assessment, identification of surgically relevant interindividual anatomic variance and may improve perioperative outcomes.

Discussion

Three-dimensional reconstruction using computed tomography imaging improves surgical planning and there is evidence that it results in shorter operative times, less intraoperative blood loss and lower rates of surgical conversion, as it can be applied both pre- and intraoperatively.

The intersegmental pulmonary vein is not always located on the intersegmental plane of the lung: Evaluation with 3-dimensional volume-rendering image reconstruction

Objective

To clarify whether intersegmental pulmonary veins are always located on the intersegmental plane and determine the division from which blood flows into them.

Methods

We analyzed representative intersegmental veins located between the upper/lingular and superior/basal division of the lungs using preoperative chest computed tomography (CT) DICOM data from 22 patients who underwent lobectomy or segmentectomy during 2020. The location and blood flow of V³a+b and V⁶b+c were assessed using REVORAS (Ziosoft), a novel volume-rendering 3-dimensional (3D) image reconstruction software dedicated to lung segmentectomy.

Results

The V³a+b was in the upper division and on the intersegmental plane between the upper and lingular divisions of the left lung in 11 patients (50%) each. A main root of V³a+b was not found in the lingular division, but some peripheral flow in the V³a+b was derived from it in 14 patients (64%). The V⁶b+c was found in the superior division of the right lower lobe in 13 patients (59%) and the left lower lobe in 10 patients (45%), and on the intersegmental plane between the superior and basal division of the right lower lobe in 6 patients (27%) and the left lower lobe in 10 patients (45%). A main root of V⁶b+c was imperceptible in the basal division. Some peripheral blood flow was derived from the basal division in 6 patients (27%) with V⁶b+c veins located in the right lower lobe and in 8 patients (36%) with V⁶b+c veins located in the left lower lobe.

Conclusions

Precise evaluation of intersegmental veins using preoperative volume-rendering 3D reconstructed CT images provides useful anatomic information for separating intersegmental pulmonary parenchyma.

Progress in three-dimensional computed tomography reconstruction in anatomic pulmonary segmentectomy

The number of minimally invasive surgeries, such as video-assisted thoracoscopic surgery and robot-assisted thoracoscopic surgery, has increased enormously in recent years. More and more relevant studies report that anatomic pulmonary segmentectomy has the same effect as traditional lobectomy in the surgical treatment of early stage non-small cell lung cancer (diameter less than 2.0 cm). Segmentectomy requires sufficient knowledge of the location of the pulmonary nodules, as well as the anatomy of the target segments, blood vessels, and bronchi. With the rapid development of imaging technology and three-dimensional technology, three-dimensional reconstruction has been widely used in the medical field. It can effectively assess the vascular branching patterns, discover the anatomic variations of the blood vessels and bronchi, determine the location of the lesion, and clarify the division of the segments. Therefore, it is helpful for preoperative positioning, surgical planning, preoperative simulation and intraoperative navigation, and provides a reference for formulating an individualized surgical plan. It therefore plays a positive role in anatomic pulmonary segmentectomy. This study reviews the progress made in three-dimensional computed tomography reconstruction in anatomic pulmonary segmentectomy.

A right pulmonary vein abnormality treated with 3D CT assistance in thoracoscopic surgery for esophageal cancer: a case report

BACKGROUND

Anomalous bifurcation of the right superior pulmonary vein is an important anomaly that should be recognized not only in respiratory and cardiac surgeries, but also in esophageal surgery for the safe performance of surgery. We report a case in which thoracoscopic esophagectomy was safely performed using preoperative three-dimensional computed tomography (3D CT) imaging.

CASE PRESENTATION

An 81-year-old male patient received an upper gastrointestinal endoscopy, which revealed a 20-cm incisor at the entrance, 43-cm EGJ, and 30-mm large type 1 + IIc lesion between the 23-cm and 26-cm incisors; biopsy showed squamous cell carcinoma (SCC). Contrast-enhanced CT showed wall thickening in the anterior wall of the upper thoracic esophagus, without evidence of multi-organ invasion or lymph node metastasis. In addition, a break in the right pulmonary vein passing dorsal to the right main bronchus and flowing directly into the left atrium was observed, and 3D CT was performed preoperatively to confirm the 3D positioning. Positron emission tomography (PET)-CT showed a high degree of accumulation (SUVmax 19.95) in the upper thoracic esophagus. The patient was diagnosed with upper thoracic esophageal cancer, cT2N0M0 cStage II, and underwent thoracoscopic subtotal esophagectomy (three-region dissection) and gastric tube reconstruction. The dorsal inflow of the pulmonary vein in the right main bronchus, which was recognized on preoperative CT, was confirmed and preserved. The pathological diagnosis was basaloid squamous cell carcinoma, pT1b(SM1)N0(0/58)M0 pStage I. The postoperative course was uneventful, and the patient was discharged on postoperative day 20.

CONCLUSIONS

The anomalous bifurcation of the pulmonary vein in the right upper lobe area required attention because of its potential to cause massive bleeding and difficulty in securing the operative field if misidentified and damaged during surgery. Although it is not frequently encountered, it is the bifurcation anomaly that esophageal surgeons must bear in mind due to its severe consequences. Preoperative image-reading and intraoperative manipulation of this vessel are imperative for surgical safety.

[Single-phase Pulmonary Arteriovenous Separation CT Protocol with Estimated Time of Arrival Method Using 3rd Generation Dual Source CT: Its Success Rate of Pulmonary Arteriovenous Separation in Our Experience of 223 Cases]

We retrospectively investigated the success rate of pulmonary arteriovenous separation in a single-phase computed tomography (CT) protocol using the estimated time of arrival (ETA) method. A total of 223 patients who underwent a single-phase CT protocol using the ETA method for pulmonary arteriovenous separation were included in the analysis. Dual source CT (SOMATOM Force, SIEMENS) was used for imaging. The tube voltage was 80 kVp, and the scan mode was turbo flash spiral mode. CT values of main pulmonary artery (MPA), peripheral pulmonary artery (pPA), peripheral pulmonary vein (pPV), left atrium (LA), ascending aorta (AAo) and descending aorta (DAo) were measured. When the difference in CT values on the central side was 100 Hounsfield unit (HU) or more, it was judged that the separation was successful. The mean CT values were 671.9±154 HU for MPA, 424.4±81.2 HU for LA, 551.1±142.6 HU for pPA, 351.6±94.0 HU for pPV, 362.2±75.8 HU for AAo, and 282.7±83.7 HU for DAo. The mean difference in CT values of the pulmonary artery and vein was 247.5±138.9 HU on the central side and 199.5±133.0 HU on the peripheral side. There were 90.1% of cases where the difference in CT values on the central side was 100 HU or more. In addition, a strong positive correlation (r=0.849, p<0.001) was found between the CT value of MPA and the CT value difference on the central side. The success rate of pulmonary arteriovenous separation by the ETA method, which is a method that enables stable pulmonary arteriovenous separation, was 90.1%.

Demarcation of arteriopulmonary segments: a novel and effective method for the identification of pulmonary segments

Objective

Each pulmonary segment is an anatomical and functional unit. However, it is fundamentally difficult to precisely distinguish every pulmonary segment using the conventional pulmonary intersegmental planes from computed tomography images. Building arteriopulmonary segments is likely to be an effective way to identify pulmonary segments.

Methods

The thoracic computed tomography images of 40 patients were collected. The anatomic structures of interest were extracted in the transverse, sagittal, and coronal planes using the semi-automated segmentation tools provided by Amira software. The intrapulmonary vessels were subsequently segmented and reconstructed. The distributions of the pulmonary arteries, veins, and bronchi were observed. In patients with pulmonary masses, the mass was also reconstructed.

Results

The three-dimensional reconstructed images showed the branches of the pulmonary artery ramified up to their eighth order covering the entire lung as well as evident intersegmental gaps without pulmonary arteries. The segmental artery was closely accompanied by the segmental bronchi in 486 pulmonary segments (90% of total number of segments). The size and spatial location of the pulmonary mass within a pulmonary segment were also clearly visible.

Conclusions

Demarcation of arteriopulmonary segments can be used to precisely distinguish every pulmonary segment and provide its detailed anatomical structure before pulmonary segmentectomy.

Surgeon Knowledge of the Pulmonary Arterial System and Surgical Plan Confidence Is Improved by Interactive Virtual 3D-CT Models of Lung Cancer Patient Anatomies

Objective: Interactive three-dimensional virtual models of pulmonary structures (3D-CT) may improve the safety and accuracy of robotic-assisted thoracic surgery (RATS). The aim of this study was to evaluate the impact of 3D-CT models as an imaging adjunct on surgical confidence and anatomical assessment for lobectomy planning. Methods: We retrospectively analyzed the response of 10 specialist thoracic surgeons who each reviewed 10 pre-operative images of patients undergoing robotic-assisted lobectomy lung cancer cases from June to November 2018 in our institute, resulting in 100 data points. The number of arteries, veins, and bronchi entering the resected lobes were determined from the operation video recording by the operating surgeon. 3D-CT models were generated for each case and made available for online visualization and manipulation. Thoracic surgeons were invited to participate in the survey which consisted of evaluation of CT (control) and 3D-CT (intervention) models. A questionnaire regarding anatomical structures, surgical approach, and confidence was administered. Results: Ten participants were recruited. 3D-CT models led to a significant (p < 0.003) increase in the surgeons' ability to correctly identifying pulmonary arteries entering the resection lobes in 35% (CT) and 57% (3D-CT) of cases. A significant (p < 1e-13) improvement in anatomy assessment and surgical plan confidence was observed for the 3D-CT arm, with median Likert scale scores of "2-Slightly easy" (CT) and "4-Very easy" (3D-CT). Conclusion: The use of 3D-CT models for thoracic surgery planning increases the surgeon confidence in recognizing anatomical structures, largely by enhanced appreciation of anatomical variations in the segmental pulmonary arterial system. Further studies are needed to investigate if 3D-CT models can be used in providing precise information about segmental artery distribution and therefore surgical planning of sub-lobar resections.

Anatomical analysis of the left upper lobe of lung on three-dimensional images with focusing the branching pattern of the subsegmental veins

Background

A clear understanding of the anatomical characteristics of the pulmonary veins (PVs) is essential for the successful performance of segmentectomy and important to avoid intraoperative pulmonary vessels injury. However, there is no report showing the relations between the branching patterns of PVs and pulmonary arteries (PAs). Moreover, internationally accepted symbols for describing PVs remain unavailable. For anatomically assessing the branches and courses of the subsegmental veins in the left upper lobe (LUL), the diverse branching patterns of blood vessels and bronchi should be investigated.

Methods

The branching patterns and intersegmental courses of PVs were assessed by performing three-dimensional image analysis of the bronchi, and PAs and PVs in the LUL in 103 patients who were scheduled to receive segmentectomy in LUL from January 2008 through August 2012.

Results

Branching types of the bronchi and pulmonary vessels failed to be independent each other. Although the combinations of anterior extension type of bronchus with the inter-lobar type (IL-type) of arterial branching pattern were often observed, but those with the mediastinal type (M-type) were rarely observed. The combinations of apical vein dominant type with the IL-type of arteries, and intermediate and central vein types with the M-type were often observed. Since LUL was adjoined by various subsegments, and the intersegmental pulmonary veins showed diverse patterns.

Conclusions

This study found the relationship among PA, PV, and bronchus patterns, in the subsegment where the branching patterns were fixed in 103 cases. This study discovered PVs that was difficult to be named by the conventional naming systems because of the diversity of the locations in the subsegment.

Preoperative evaluation of the segmental artery by three-dimensional image reconstruction vs. thin-section multi-detector computed tomography

Background

“Exoview” is a three-dimensional (3D) image reconstruction software developed by our medical team independently. The aim of this retrospective study was to compare the use of 3D image reconstruction, and thin-section multi-detector computed tomography (MDCT) in the preoperative evaluation of the segmental artery (SA).

Methods

From May 2018 to May 2019, 52 patients received anatomical segmentectomy in our department. All patients received computed tomography pulmonary angiography (CTPA) by use of a 64-slice MDCT before operation. Then the 2D CT data were converted into 3D format by use of Exoview. We compared the intraoperative findings of the SA branches with 3D images and thin-section MDCT.

Results

The study cohort of 52 patients included 31 women and 21 men and the operative factors include operation time (148.75±53.56 min), blood loss (57.31±79.68 mL), postoperative hospitalization days (6.42±3.48 days), lymph node sampling (3.00±1.50 stations) and postoperative complications (5 patients, 10%). The adenocarcinoma in situ with microinvasion was the predominant type (25 cases, 48%). There were 7 patients accepted for video-assisted thoracoscopic surgery (VATS) lobectomy with radical lymph nodes dissection because invasive adenocarcinoma was confirmed by intraoperative frozen-section analysis. One other patient was confirmed for conversion from VATS segmentectomy to an open operation because of bleeding of the bronchial artery. According to intraoperative findings, 95.7% (132 of 138) and 100% (138 of 138) of these SA branches were precisely identified on preoperative 3D image reconstruction and thin-section MDCT images. The 6 missed branches were less than 1.4 mm in actual diameter.

Conclusions

Both 3D image reconstruction and thin-section MDCT provided precise preoperative information about SA. The 3D image reconstruction software “Exoview” could visualize SA for surgeons. However, the thin-section MDCT provided a better evaluation of small SA branches.

An analysis of anatomical variations of the left pulmonary artery of the interlobar portion for lung resection by three-dimensional CT pulmonary angiography and thin-section images

PURPOSE

The purpose of the present study was to analyze the left pulmonary artery (LPA) branching pattern of the interlobar portion using three-dimensional CT pulmonary angiography (3D-CTPA) and thin-section CT images, and to attempt to diagrammatize these patterns.

MATERIALS AND METHODS

The study included 320 patients suspected of having lung cancer of the left upper/lower lobe who underwent CTPA. The number and origin of the LPA branches of the interlobar portion, A1 + 2c, A6, and lingular artery from pars interlobaris (PI), were identified meticulously using 3D-CTPA and thin-section images. We then diagrammatized the identified LPA branching patterns of the interlobar portion.

RESULTS

The diagrammatized LPA branching patterns of the interlobar portion were broadly classified into seven types in the order of bifurcation from proximal to distal. Type 1 was the most frequent (120/320, 37.5%). PI originated from the lower portion, that is, from A8 or the common trunk of A8 and A9 in 95 cases (29.7%). We could also precisely diagrammatize the LPA branching patterns of the interlobar portion into 85 types in all 320 patients.

CONCLUSION

3D-CTPA and thin-section images provided precise preoperative information regarding the LPA branching patterns of the interlobar portion.

Branching anomaly of the pulmonary ventrobasal and laterobasal arteries from the mediastinal lingular pulmonary artery

The lingular pulmonary artery is known for being frequently subjected to bifurcation anomalies, thus asserting the importance of performing three-dimensional computed tomography angiography before lung surgery for safety reasons. We report a case of branching anomaly of the left ventrobasal and laterobasal arteries, which instead of branching from the interlobar artery, branched as a common trunk from the mediastinal lingular artery. A 68-year-old man with diagnosis of rectal cancer lung metastasis in the ventral segment of left upper lobe (S3) presented branching anomaly of the pulmonary artery, which was detected by a preoperative three-dimensional computed tomography angiography. Although there was a conversion from segmentectomy to left upper lobectomy to secure the margin with the tumor, the operation was safely performed and completed by video-assisted thoracic surgery, since the vascular branching anomalies were characterized preoperatively.

Three-dimensional image simulation of primary diaphragmatic hemangioma: A case report

BACKGROUND

Fewer than 200 cases of diaphragmatic tumors have been reported in the past century. Diaphragmatic hemangiomas are extremely rare. Only nine cases have been reported in English literature to date. We report a case of cavernous hemangioma arising from the diaphragm. Pre-operative three-dimensional (3D) simulation and minimal invasive thoracoscopic excision were performed successfully, and we describe the radiologic findings and the surgical procedure in the following article.

CASE SUMMARY

A 40-year-old man was referred for further examination of a mass over the right basal lung without specific symptoms. Contrast-enhanced computed tomography revealed a poorly-enhanced lesion in the right basal lung, abutting to the diaphragm, measuring 3.1 cm × 1.5 cm in size. The mediastinum showed a clear appearance without evidence of abnormal mass or lymphadenopathy. A preoperative 3D image was reconstructed, which revealed a diaphragmatic lesion. Video-assisted thoracic surgery was performed, and a red papillary tumor was found, originating from the right diaphragm. The tumor was resected, and the pathological diagnosis was cavernous hemangioma.

CONCLUSION

In this rare case of diaphragmatic hemangioma, 3D image simulation was helpful for the preoperative evaluation and surgical decision making.

[Utility of Split-bolus Single-phase Protocol for Pulmonary Artery and Vein Separation Preoperative 3D-CTA in Lung Cancer Video-assisted Thoracic Surgery]

There are many variations in branching and running of pulmonary artery (PA) and pulmonary vein (PV). It is desirable to separate as a surgical simulation of lung cancer and important to grasp before video-assisted thoracic surgery (VATS) to perform quick and safe. Therefore, the purpose of this study was to evaluate objective and subjective image quality (contrast attenuation, separation ability, and vascular visualization) of PA and PV of splitbolus single-phase protocol (SBSPP) in preoperative three-dimensional computed tomography angiography (3DCTA). CT value of PA was 410.2±71.0 Hounsfield unit (HU), PV was 245.1±24.8 HU, difference between CT value of PA and CT value of PV was 164.5±60.9 HU. Subjective image quality of PA and PV could be visualized until more than the segmental branch level. SBSPP can obtain sufficient CT value for separate visualization of PA and PV, and before VATS useful PA and PV 3D-CTA imaging.

A rare anomaly of A4+5 on three-dimension multidetector computed tomography in lung cancer: A case report

•

We report an extremely rare anomaly in which A4 + 5 ran between V2 and V1 + 3.

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Correct anatomy of the pulmonary vessels can be known using preoperative 3D-MDCT.

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Surgery can be smoothly modified using preoperative 3D-MDCT.

Introduction

There are several anomalies of the pulmonary vessels. Clinicians need to be well informed about anatomy, particularly before video-assisted thoracic surgery, to prevent fatal complications.

Presentation of case

We report the case of an 80-year-old woman who was suspected of having lung cancer in the right lower lobe. The patient was accordingly scheduled for surgery. Three-dimension multidetector computed tomography (3D-MDCT) showed an extremely rare anomaly in which A4 + 5 ran between V2 and V1 + 3. We scheduled a non-anatomical wedge resection of the lesion and performed rapid pathological diagnosis during surgery. Because adenocarcinoma was diagnosed, we performed right lower lobectomy using video-assisted thoracic surgery. Station 11i lymph node rigidly adhered to the main pulmonary artery, V2, and intermedius bronchus. Thus, the surgery was shifted to middle and lower lobectomy.

Discussion

To the best of our knowledge, this type of anomaly has not been reported yet. Pulmonary vessels can be accurately identified using 3D-MDCT; thus, a rare anatomy can be identified, and information can be shared across the surgical team simulating familiarity with this rare anatomy.

Conclusion

Using 3D-MDCT, we could accurately divide A4 + 5 and safely perform the surgery.

Pulmonary Staple-Stump Granuloma After Segmentectomy: Two Case Reports and Comparison with Cases of Stump Recurrence

BACKGROUND Correctly diagnosing a staple-line mass after pulmonary resection for lung malignant tumor can be difficult. Differential diagnoses of recurrence, infectious mass, granuloma, and so on must be considered, despite their rarity. We report two cases of pulmonary staple-stump granuloma after segmentectomy for lung cancer. CASE REPORT Case 1 involved a 70-year-old man with small nodule in the left upper lobe identified on computed tomography (CT). Video-assisted thoracoscopic (VATS) left upper division segmentectomy was performed. Histopathological examination revealed squamous carcinoma. Follow-up CT 1 year postoperatively showed a shadow at the staple-stump, with growth evident later. CT-guided biopsy found no malignancy. However, complete left upper lobectomy was performed because of the gradually enlarging lesion. Histopathological examination revealed epithelioid granuloma. Case 2 involved a 60-year-old with suspected lung cancer in the right upper lobe. VATS right upper division segmentectomy (S2) was performed. CT at 30 months postoperatively showed a shadow at the staple line, with subsequent growth. VATS right upper lobectomy was performed. Intraoperative rapid diagnosis revealed epithelioid granuloma. These two cases were compared with five cases of staple-stump recurrence in our institution. All cases of recurrence grew concentrically or radially from the staple line with the mass surrounding the staple line. On the other hand, cases of granuloma extended along the long axis of the staple line, and 3-dimensional CT (3DCT) may help to understand the morphology. CONCLUSIONS Although preoperative differentiation of staple-line granuloma is difficult and pathological diagnosis is important, characteristic radiologic features and 3DCT may facilitate diagnosis.

A left lung abscess with a displaced subsegmental bronchus and anomalous pulmonary artery and vein: a case report

Background

Since a displaced bronchus related to the left upper lobe is an uncommon anatomical anomaly, it has a risk of being accidentally resected during left upper lobe resection unless they are identified preoperatively. A case of video-assisted thoracic surgery (VATS) segmentectomy that was safely performed under preoperative identification of a displaced subsegmental bronchus and anomalous pulmonary vessels is presented.

Case presentation

A 48-year-old woman visited our hospital because of an abnormal shadow on a radiograph on a health check. The chest computed tomography (CT) showed a multicystic mass with a diameter of 35 mm on dorsal interlobar parenchyma between the S¹⁺² and S⁶ segments in the left lung. The three-dimensional (3D) CT with multiplanar reconstruction showed that B¹⁺²b+c passed to the dorsal side of the left main pulmonary artery (PA), which was considered a displaced bronchus. The branch of A⁶ arose from the left main PA at the level of the branches of A³ and A¹⁺², more proximal than the normal anatomy, and passed to the dorsal side of a displaced B¹⁺²b+c. The branch of V¹⁺² passed between B⁶ and the bronchus to the basal segment and joined V⁶ at the dorsal side of the pulmonary hilum. Intraoperative findings of the anatomy of the bronchi and pulmonary vessels were exactly the same as the preoperative 3D CT findings, so segmentectomy of S¹⁺²b+c and S⁶ by VATS was performed safely. Then there were accessory fissures between S¹⁺² and S³ and between S⁶ and the basal segment. The pathological diagnosis was a left lung abscess.

Conclusions

A preoperative 3D CT may be helpful for identifying anatomical anomalies. An anatomical anomaly should be suspected if accessory fissure is found during surgery.

Interactive 3D Reconstruction of Pulmonary Anatomy for Preoperative Planning, Virtual Simulation, and Intraoperative Guiding in Video-Assisted Thoracoscopic Lung Surgery

OBJECTIVES

Routine imaging modalities combined with state-of-the-art reconstruction software can substantially improve preoperative planning and simplify complex procedure by enhancing the surgeon's knowledge of the patient's specific anatomy. The aim of the current study was to demonstrate the feasibility of interactive three-dimensional (3D) computed tomography (CT) reconstructions for preoperative planning and intraoperative guiding in video-assisted thoracoscopic lung surgery (VATS) with 3D vision.

METHODS

Twenty-five consecutive patients referred for an anatomic pulmonary resection by a single surgeon were included. Data were collected prospectively. All patients underwent a CT angiography in the diagnostic pathway prior to referral. 3D reconstruction of the pulmonary anatomy was obtained from CT scans with dedicated software. An interactive PDF file of the 3D reconstruction with virtual resection was created, in which all the pulmonary structures could be individually selected. Furthermore, the reconstructions were used for intraoperative guiding on double monitor during VATS with 3D vision.

RESULTS

In total, 26 procedures were performed for 5 benign and 21 malignant conditions. Lobectomy and segmentectomy were performed in 20 (76.9 %) and 6 (23.1%) cases, respectively. In all patients, preoperative 3D reconstruction of pulmonary vessels corresponded with the intraoperative findings. Reconstructions revealed anatomic variations in 4 (15.4%) patients. No conversion to thoracotomy or in-hospital mortality occurred.

CONCLUSIONS

Preoperative planning with interactive 3D CT reconstruction is a useful method to enhance the surgeon's knowledge of the patient's specific anatomy and to reveal anatomic variations. Intraoperative 3D guiding in VATS with 3D vision is feasible and could contribute to the safety and accuracy of anatomic resection.

Aberrant mediastinal trunk of pulmonary artery

Anatomic variations of the pulmonary artery (PA) cause vascular injuries and result in critical mistakes. Here we report the first case of lung cancer with a fissureless left upper lobectomy, an aberrant mediastinal trunk of the lingular and basal segments of the PA. A 65-year-old man was referred to our hospital with a solid mass on the left upper lobe. A fissureless left upper lobectomy was performed due to severe incomplete lobulation. Intraoperative findings showed an extremely rare anatomic variation (left A⁵+A⁸+A⁹b) that arose as a common trunk from the left main PA. To prevent intraoperative injury, it is essential to consider the unexpected mediastinal inferior branch and perform a surgical procedure such as fissureless lobectomy upon encountering incomplete lobulation.

Nanoparticle-based CT visualization of pulmonary vasculature for minimally-invasive thoracic surgery planning

Purpose

To evaluate CF800, a novel lipid-based liposomal nanoparticle that co-encapsulates indocyanine green (ICG) and iohexol, for CT imaging of pulmonary vasculature in minimally-invasive thoracic surgery planning.

Methods

CF800 was intravenously administered to 7 healthy rabbits. In vivo CT imaging was performed 15 min post-injection, with a subset of animals imaged at 24h, 48h, and 72h post injection. Signal-to-background ratios (SBR) were calculated at the inferior vena cava and compared across time-points. A similar protocol was applied to 2 healthy pigs to evaluate the feasibility and efficacy in a large animal model. To evaluate the feasibility of clinical application, a survey was completed by 7 surgical trainees to assess pre- and post-injection CT images of rabbits and pigs. Responses on the discernibility of pulmonary vasculature sub-branches and comfort level to use the images for pre-operative planning were collected and analyzed.

Results

CF800 injection improved visualization of pulmonary vessels in both rabbit and pig models. The SBR of rabbit pulmonary vasculature was significantly higher after CF800 injection (range 3.7–4.4) compared to pre-injection (range 3.3–3.8, n = 7; p<0.05). SBR remained significantly different up to 24 hours after injection (range 3.7–4.3, n = 4; p<0.05). Trainees’ evaluation found the post-injection CT images had significantly higher discernibility at the second vessel branch generation in both rabbit and pig models. Trainees identified smaller vasculature branch generations in the post-injection images compared to the pre-treatment images in both rabbit (mean 6.7±1.8 vs 5.4±2.1; p<0.05) and pig (mean 6.7±1.8 vs 5.4±2.1; p<0.05). Trainees were significantly more comfortable using post-injection images for surgical planning compared to the pre-injection images (rabbit: 8.1±1.1 vs. 4.7±2.1; pig: 7.6±2.1 vs. 4.9±2.2; p<0.05).

Conclusion

CF800 provides SBR and contrast enhancement of pulmonary vasculature which may assist in pre-surgical CT planning of minimally invasive thoracic surgery.

Computed tomography pulmonary angiography and venography with a low dose of contrast medium

The authors developed a method to ensure sufficient opacification of pulmonary vasculature for separate depiction of arteries and veins in three-dimensional form with a small dose of contrast medium utilizing a test injection to determine optimal timing of computed tomography (CT) scanning. The dose was determined by a simulation based on a pharmacokinetic model. The contrast medium was administered at a rate of 5.0 mL/s for 3 s, followed by helical scanning at the timing determined by a dynamic CT scanning following the test injection. Images of 20 consecutive patients acquired with a 64-row CT scanner were evaluated. Quality of vessel depiction was assessed on the basis of the following: HU values at the main pulmonary artery (MPA) and left atrium (LA), distance between the pleural surface and the distal end of the pulmonary vessels on three-dimensional CT pulmonary arteriography and venography (3D-CTPAV), and subjective visual assessment of quality of the 3D-CTPAV images. Time to generate the 3D-CTPAV images was recorded. The mean ± standard deviation (SD) of the HU values at MPA/LA and the distances to the pleural surface for pulmonary arteries/veins were 448.0 ± 123.1/277.3 ± 60.85 HU and 9.21 ± 3.60/10.7 ± 5.45 mm, respectively. The image quality was visually rated as excellent for all of the patients. The mean time ± SD to generate 3D-CTPAV images was 13.6 ± 6.7 min. In conclusion, three-dimensional images of the pulmonary vasculature can be created using 21 mL (including 6 mL for the test injection) of contrast medium.

Comprehensive study of pulmonary hilam with its clinical correlation

INTRODUCTION

Awareness of pulmonary hilar variations is essential for lobectomy of lung.

MATERIALS AND METHODS

We studied 54 left and 49 right hilum of formalin fixed adult cadaveric lungs. Morphologic and mophometric details were recorded and variations were noted.

RESULTS

Classical picture of hilum was found in 35.19% left lung and 40.82% right lung. Morphological variations were more on left side (64.81%) than right side (59.18%) in terms of numbers of structures. On the left side, highest percentage of variable structure was bronchus (46.3%) followed by pulmonary artery (37.31%) and lowest by pulmonary vein (31.48%) whereas on right side, percentage for variable pulmonary artery and vein were same (36.73%) followed by bronchi (20.41%). Maximum number of pulmonary veins was five, pulmonary artery was three and accessory bronchus was two on both side hila. In morphometric measurement, mean vertical length of hilum was more on right side whereas anteroposterior length was more on left side. Right hilum is slightly lower and anteriorly placed than left hilum in the mediastinal surface of lung. Significant correlations between vertical length of lung and hilum and antero-postero length of lung and hilum of left and right sides were found.

CONCLUSIONS

By analysis and comparison with previous studies, present study concludes that morphology of pulmonary hila is extremely variable which contributes significant consequences in the field of pulmonary resection.

Surgical management of non-cystic fibrosis bronchiectasis

Non-cystic fibrosis bronchiectasis (bronchiectasis) is an abnormal dilatation of the bronchi and bronchioles, resulting from a prolonged recurrent infectious process due to various causes and predisposing factors. This disease has several etiologies and affects a heterogeneous population of patients. The most important viewpoint for the surgical management of bronchiectasis is to select appropriate candidates for surgery and conduct suitable anatomic lung resections at the right time under appropriate conditions. The ideal candidates for lung resection are symptomatic patients with focal disease due to truly localized bronchial pathology regardless of optimal and absolute medical management.

Intraoperative diagnosis with abnormal branching of the left A8 pulmonary artery from the left main pulmonary artery

BACKGROUND

Safety is of vital importance for lung resection. The dissection of pulmonary vessels is associated with vascular injury and bleeding, and identification of the vessels is necessary. The most common abnormal branching pattern of the left pulmonary artery is the mediastinal lingular artery. However, a mediastinal basal pulmonary artery is very rare. A case of abnormal branching from the left pulmonary artery to S8 which was diagnosed intraoperatively, and, thus, its dissection was avoided, is reported.

CASE PRESENTATION

A 76-year-old woman with rheumatoid arthritis was diagnosed with left upper lung adenocarcinoma and visited our hospital. Contrast CT was not performed due to renal dysfunction, and abnormal branching of the left pulmonary artery was not identified. Video-assisted thoracoscopic left upper lobectomy and lymphadenectomy were performed. After the upper pulmonary vein was dissected and tissue around it was detached carefully, a pulmonary mediastinal branch from the left main pulmonary artery was identified descending between the upper pulmonary vein and upper bronchus. It was possible to separate the interlobar fissure safely and preserve A8. On retrospective examination, non-contrast CT showed A8.

CONCLUSIONS

Although preoperative identification of left pulmonary mediastinal branches was difficult by non-contrast CT, a careful surgical procedure preserved the left pulmonary mediastinal A8.

Variations of pulmonary vein drainage critical for lung resection assessed by three-dimensional computed tomography angiography

Background

It is important to understand pulmonary vein drainage pattern variations and their frequency in order to perform safe anatomical pulmonary resection.

Methods

Variations and frequencies were assessed using three‐dimensional computed tomography angiography (3D‐CT) in 194 patients. In cases where the tumor or lymph node caused atelectasis or compression of hilar structures, the involved lobes were excluded from the analyses.

Results

We confirmed variant drainage patterns in 15/189 (8.0%) patients in the right upper lobe (RUL), 29/189 (15.3%) in the right middle lobe (RML), 18/192 (9.5%) in the right lower lobe (RLL), and 5/187 (2.6%) in the left upper lobe (LUL). There was no variant type in the left lower lobe (LLL). There were 14 (7.4%) cases of anomalous superior posterior pulmonary vein of RUL (V²) drainage: V2 draining to the superior pulmonary vein (SPV) (n = 2, 1.1%), V2 to the inferior pulmonary vein (IPV) (n = 7, 3.7%), V2 to the left atrium (LA) (n = 2, 1.1%), and V⁶ to the apical pulmonary vein of the RLL (n = 3, 1.6%). There was a posterior pulmonary vein, V³ to RML pulmonary vein in one case (0.5%). The RML pulmonary vein drained into the IPV in 14 (7.4%) and into the LA in 15 (7.9%) cases. The right V6 directly drained into the LA in 15 (7.9%) and V⁶ into the SPV in 3 (1.6%) cases. The lingular pulmonary vein drained into the IPV in one case (0.5%) and into the LA in two cases (1.1%). The inferior lingular pulmonary vein V⁵ drained into the IPV and into the LA in one case (0.5%), respectively.

Conclusion

We describe anomalous pulmonary venous drainage patterns and their frequencies particular to anatomic surgical resection. 3D‐CT is useful to find such variations.

Unusual case of subxiphoid uniportal VATS right upper lobectomy in a patient with interrupted inferior vena cava with azygous continuation

Interrupted IVC (also known as Azygos continuation of the inferior vena cava) is a relatively uncommon congenital condition with prevalence 1.5% (0.2-3%) of the general population (Bass et al.). Although it's usually asymptomatic condition, splenic or cardiac abnormalities could be associated (Hardwick et al.). Incidental diagnosis during prenatal ultrasound screening or by routine imaging is the most common scenario. Special attention is required during right side thoracic procedures surgical resections in order to avoid scarifying the azygos vein that could lead to fatal results (Effler et al.). We herein report a video documented case of right upper lobectomy and mediastinal lymph node dissection for non-small cell carcinoma of lung in a patient who had interrupted hepatic segmental branch of the IVC. The procedure was performed via the subxiphoid uniportal VATS approach.

Prevention and management of intraoperative crisis in VATS and open chest surgery: how to avoid emergency conversion

Video assisted thoracic surgery (VATS) has become a routinely utilized approach to complex procedures of the chest, such as pulmonary resection. It has been associated with decreased postoperative pain, shorter length of stay and lower incidence of complications such as pneumonia. Limitations to this modality may include limited exposure, lack of tactile feedback, and a two-dimensional view of the surgical field. Furthermore, the lack of an open incision may incur technical challenges in preventing and controlling operative misadventures leading to major hemorrhage or other intraoperative emergencies. While these events may occur in the best of circumstances, prevention strategies are the primary means of avoiding these injuries. Unplanned conversions for major intraoperative bleeding or airway injury during general thoracic surgical procedures are relatively rare and often can be avoided with careful preoperative planning, review of relevant imaging, and meticulous surgical technique. When these events occur, a pre-planned, methodical response with initial control of bleeding, assessment of injury, and appropriate repair and/or salvage procedures are necessary to maximize outcomes. The surgeon should be well versed in injury-specific incisions and approaches to maximize adequate exposure and when feasible, allow completion of the index operation. Decisions to continue with a minimally invasive approach should consider the comfort and experience level of the surgeon with these techniques, and the relative benefit gained against the risk incurred to the patient. These algorithms may be expected to shift in the future with increasing sophistication and capabilities of minimally invasive technologies and approaches.

The first rib hypoplasia and the aberrant pulmonary artery branch detected by three-dimensional computed tomography in a surgical case with apical lung cancer, a case report

Background

The complete resection is one of the most crucial requirements to achieve favorable outcomes in oncologic surgery. The apex of the lung is surrounded complicatedly by the clavicle, the first rib, the subclavian artery and vein, and the brachial plexus. Therefore, the image information especially about the infiltration of adjacent anatomic structures, facilitates the surgery in the apical lung cancer.

Case presentation

A 70-year-old man presented at our hospital with a computed tomography (CT) scan showing a tumor at the left lung apex that infiltrated the chest wall. Two anatomical anomalies were found, which were the first rib hypoplasia and the aberrant pulmonary artery branch. The three-dimensional (3D) CT enhanced with using bolus tracking method, simultaneously revealed that the subclavian vessels existed between the clavicle and the second rib, and the left lingual pulmonary artery and the ventrobasal pulmonary artery diverged from the left main pulmonary artery as the first branch. We diagnosed the tumor as a primary lung squamous cell carcinoma that infiltrated the second rib, because sputum cytology suggested squamous cell carcinoma. Left lung upper lobectomy with lymph node dissection and chest wall resection (the second and third ribs) were performed with caution for the anatomical anomalies. The pathological diagnosis was pleomorphic carcinoma (5.0 × 3.0 × 1.9 cm) that invaded the second costal bone, and the pathological stage was confirmed to be pT3N0M0. Pathologically curative resection was accomplished. The patient was discharged from the hospital on 10 days after surgery.

Conclusion

The 3D-CT precisely detected the anomalous structure consisted with the clavicle, the second rib, the subclavian artery and vein, the aberrant pulmonary artery branch. In the present case with the apical lung cancer, the evaluation of the anatomical structure via 3D-CT facilitated to achieve a pathological complete resection.

Electronic supplementary material

The online version of this article (doi:10.1186/s12893-016-0199-1) contains supplementary material, which is available to authorized users.

Lobectomy for a mediastinal basal pulmonary artery

Anatomical variations of the pulmonary artery increase the risks for vessel injury and critical mistakes during pulmonary artery resection. The mediastinal basal pulmonary artery is a rare branch abnormality and is the first branch of the pulmonary artery to flow into the basal segment. We report a patient who underwent video-assisted thoracic surgery (VATS) right lower lobectomy for lung cancer with a mediastinal basal pulmonary artery. The mediastinal basal pulmonary artery was detected preoperatively by computed tomography. During VATS, this artery was found with careful dissection by dividing the lung parenchyma within the fissure, and right lower lobectomy was safely performed.

Potentially overlooked branches of the left pulmonary artery

BACKGROUND

During pulmonary resection, we sometimes encounter "pitfall branches" of the pulmonary artery, which could cause serious vessel injury. Current computed tomography and computer-processing technology can identify the pulmonary artery along the peripheral bronchus, thereby revealing the true rates of different pulmonary artery branching patterns. Knowledge of these branching patterns allows safe and definitive surgery.

METHODS

In 186 cases of left lung resection performed at our institution from January 2006 to September 2011, two general thoracic surgeons and one radiologist independently reviewed computed tomography images and examined the branches of the pulmonary artery arising from the pars mediastinalis.

RESULTS

Branching patterns of the lingular artery included 17 (9.2%) cases with mediastinal origin, 50 (26.9%) with interlobar and mediastinal origin, and 119 (63.9%) with interlobar origin. The 2 types of lingular artery of mediastinal origin, which were potentially overlooked during surgery, were observed in 36.1% of cases. This was a higher rate than previously reported. Moreover, a mediastinal basal pulmonary artery (A(5+8+10) abnormal branching) was seen in one case.

CONCLUSION

Potentially overlooked branches of the left pulmonary artery arising from the pars mediastinalis are much more frequent than we expected. It is crucial to understand the branching pattern of the pulmonary artery by preoperative computed tomography assessment.

Great Vessel Injury in Thoracic Surgery

The potential for intraoperative bleeding is inherent to the practice of thoracic surgery due to the presence of multiple vital vascular structures, complex anatomy, and constant cardiorespiratory motion. Careful and detailed preoperative evaluation and planning, comprehensive review of imaging studies, and a thorough knowledge of the operative procedure, anatomic relationships, and potential complications are of the highest importance in prevention and avoidance of bleeding complications. Preparation with a clear crisis management plan ensures an effective and expedited response when intraoperative bleeding occurs.

Abnormal branch of right pulmonary artery (A7): a case report and literature review

In thoracic surgery, anatomic variations of pulmonary artery increase the risks for vessel injury and critical mistakes during pulmonary artery resection. We report a case of lung cancer with an extremely rare branch, a mediastinal A7 pulmonary artery. Some case reports of the mediastinal pulmonary artery exist until now. However, to the best of our knowledge, this is the first case of a medial basal segmental artery (from the following, it is referred to as A7) branching directly from main pulmonary artery in the literature. Therefore, there is no report that showed three-dimensional computed tomography (3D-CT) and operative findings. So, these information is very useful for thoracic surgeon. A 67-year-old man was admitted to our hospital in order to undergo operation for the treatment of lung cancer. We detected the anomalies preoperatively by 3D-CT. The 3D-CT shows the A7 pulmonary artery branches from the right main pulmonary artery directly. According to previous literature, the cases of a single branch from main pulmonary artery to lower lobe are only five cases. And, the only two of them are right side including our case. In spite of an extremely rare case, we were able to successfully perform a right middle lobectomy because the information obtained from the 3D-CT findings was sufficiently understood preoperatively.

Abnormal branching of the left lingular pulmonary artery diagnosed by three-dimensional computed tomographic angiography in a patient with lung cancer: a case report

Background

In general, there are several anomalies of the pulmonary artery. The mediastinal lingular pulmonary artery is well-known for its abnormal branching from the pulmonary artery. However, other types of variation are rare.

Case presentation

We herein report the case of a patient with primary lung cancer who underwent left upper lobectomy in which the lingular pulmonary artery branching from the mediastinal basal artery was demonstrated by preoperative three-dimensional computed tomographic (3D-CT) angiography.

Conclusions

A preoperative evaluation using 3D-CT angiography was useful for detecting the abnormal pulmonary branching in this patient because it allowed for the precise division of the pulmonary arteries during surgery.

Preoperative (3-dimensional) computed tomography lung reconstruction before anatomic segmentectomy or lobectomy for stage I non-small cell lung cancer

OBJECTIVES

Accurate cancer localization and negative resection margins are necessary for successful segmentectomy. In this study, we evaluate a newly developed software package that permits automated segmentation of the pulmonary parenchyma, allowing 3-dimensional assessment of tumor size, location, and estimates of surgical margins.

METHODS

A pilot study using a newly developed 3-dimensional computed tomography analytic software package was performed to retrospectively evaluate preoperative computed tomography images of patients who underwent segmentectomy (n = 36) or lobectomy (n = 15) for stage 1 non-small cell lung cancer. The software accomplishes an automated reconstruction of anatomic pulmonary segments of the lung based on bronchial arborization. Estimates of anticipated surgical margins and pulmonary segmental volume were made on the basis of 3-dimensional reconstruction.

RESULTS

Autosegmentation was achieved in 72.7% (32/44) of preoperative computed tomography images with slice thicknesses of 3 mm or less. Reasons for segmentation failure included local severe emphysema or pneumonitis, and lower computed tomography resolution. Tumor segmental localization was achieved in all autosegmented studies. The 3-dimensional computed tomography analysis provided a positive predictive value of 87% in predicting a marginal clearance greater than 1 cm and a 75% positive predictive value in predicting a margin to tumor diameter ratio greater than 1 in relation to the surgical pathology assessment.

CONCLUSIONS

This preoperative 3-dimensional computed tomography analysis of segmental anatomy can confirm the tumor location within an anatomic segment and aid in predicting surgical margins. This 3-dimensional computed tomography information may assist in the preoperative assessment regarding the suitability of segmentectomy for peripheral lung cancers.

An analysis of variations in the bronchovascular pattern of the right upper lobe using three-dimensional CT angiography and bronchography

Objectives

General thoracic surgeons must be familiar with anatomical variations in the pulmonary bronchi and vessels. We analyzed variations in the bronchovascular pattern of the right upper lung lobe using three-dimensional CT angiography and bronchography and then compared our results with those of previous reports.

Methods

We reviewed anatomical variations in the right upper pulmonary bronchus and vessels of 263 patients using 3DCT angiography and bronchography images obtained using a 64-channel multidetector CT and workstation running volume-rendering reconstruction software.

Results

Variations in the pulmonary vein were classified into four types: the “anterior-plus-central vein type” was the most common, noted in 219 cases (83.2 %). The “anterior vein type” was evident in 23 cases (8.8 %), a significantly lower incidence than in previous reports (p < 0.001). Also, the branching patterns of the segmental arteries of the pulmonary artery differed partially from those noted in previous reports. Furthermore, we identified some new variations. The “B¹- or B²-defective branch type” bronchus was noted in 19 cases (7.2 %), which was a higher prevalence than that in previous reports.

Conclusion

We explored the bronchovascular pattern and the frequency of variations in the right upper lobe using a large number of 3DCT images. The incidences of variations differed, sometimes significantly, from those noted by previous reports. Moreover, we report some new branching variations. Our data can be used by thoracic surgeons to perform safe and precise lung resections.

Electronic supplementary material

The online version of this article (doi:10.1007/s11748-015-0531-1) contains supplementary material, which is available to authorized users.

[Development of estimated time of arrival method and usefulness in pulmonary artery/vein separation 3D-CT]

We have developed an estimated time of arrival (ETA) method as a new single-phase scan for pulmonary artery/vein separation. This method enables differentiation of CT values between arteries and veins by means of two-step consecutive injection of contrast medium based on the pulmonary circulation time. This paper presents an overview of the ETA method and scan technique. Since the ETA method is a single-phase scan, it uses a low radiation dose compared with the conventional multi-phase scan. Moreover, this method eliminates gaps due to breath holding. The ETA method can detect irregularities and obtain high-quality pulmonary artery/vein separation 3D-CT images.

Lung cancer in situs inversus totalis (SIT)--literature review

We present 21 studies of cases of lung cancer in patients with situs inversus totalis (SIT) published worldwide. The first case was described in 1952. Thirteen patients were from Japan, 4 from Eastern Europe, including 2 Polish cases from the authors` center (Department of Thoracic Surgery, Pomeranian Medical University in Szczecin, Poland), 2 from Western Asia, 1 from the U.S. and 1 from Australia. Male patients (20/21) as well as left-sided lung cancer cases (14/21) and squamous cell carcinoma cases (8/21) dominated in the entire group. Thirteen patients underwent surgical treatment. There were 10 left-sided and 3 right-sided surgical interventions with uneventful intra- and postoperative course. Explorative thoracotomy was performed in one case only on the right side. Upper lobectomy was performed in 5 cases, pneumonectomy in 3 cases, lower bilobectomy and middle lobectomy in one case and lower lobectomy in two cases. Surgery was performed through thoracotomy in 10 cases, VATS-assisted approach in two cases and sternotomy in one case. Descriptions of the surgical anatomy confirmed mirror image of the anatomy in all cases and were consistent with the preoperative CT images. Preoperative diagnosis was discussed including the role of 3-D reconstruction of CT for improving perioperative safety in this group of patients. In conclusion, lung cancer/SIT cases despite inversed but regular anatomy can be operated on radically as cases with normal anatomy with preservation of intraoperative security level.

Virtual segmentectomy based on high-quality three-dimensional lung modelling from computed tomography images

OBJECTIVES

The aim of this study was to demonstrate the feasibility and efficacy of a novel simulation software called, virtual segmentectomy.

METHODS

We developed the segmentectomy simulation system, which was programmed to analyse the detailed 3D bronchovascular structure and to predict the appropriate segmental surface and surgical margin, based on lung modelling from CT images.

RESULTS

We have attempted this novel technique for 3 cases of pulmonary metastases and 1 case of multiple lung cancer. For validation, the predicted resection margin was compared with the actual resected specimen. The surgical surface, as estimated by the simulation, was compared with the surface of the specimen and a surgical video. To test its feasibility, the operation time, blood loss, durations of chest tube placement and hospitalization as well as pathological findings were assessed.

CONCLUSIONS

Preoperative simulation and intraoperative guidance by virtual segmentectomy could contribute significantly to determining the most appropriate anatomical segmentectomy and curative resection.

Recent advances in video-assisted thoracoscopic surgery for lung cancer

As a result of increased use of CT in both screening and daily practice, the number of early lung cancers has increased enormously. Surgeons pursue both curativity and reduced invasiveness in treating patients with early stage lung cancer; therefore, minimally invasive operations, such as video-assisted thoracoscopic surgery (VATS) lobectomy are now being routinely performed. Most previous reports have shown that there is no difference in mortality and local recurrence between open surgery and VATS in stage I patients. However, surgeons' improved technical experience and patients' demands could soon make VATS lobectomy the operative method of choice for early stage lung cancer. Moreover, the indications for VATS are expanding to encompass complex procedures such as segmentectomy or sleeve resection. Training and dissemination of the technique and the monitoring of outcomes are necessary.