Semi-automated vs. manual 3D reconstruction of central mesenteric vascular models: the surgeon’s verdict

Jejunal Lymphatic and Vascular Anatomy Defines Surgical Principles for Treatment of Jejunal Tumors

BACKGROUND

The jejunum has a wide lymphatic drainage field, making radical surgery difficult.

OBJECTIVE

Extrapolate results from 2 methodologies to define jejunal artery lymphatic clearances and lymphovascular bundle shapes for radical bowel-sparing surgery.

DESIGN

Two cohort studies.

SETTINGS

The first data set comprised dissections of cadavers at the University of Geneva. The second data set incorporated preoperative 3-dimensional CT vascular reconstructions of patients included in the "Surgery with Extended (D3) Mesenterectomy for Small Bowel Tumors" clinical trial.

PATIENTS

Eight cadavers were dissected. The 3-dimensional CT data set included 101 patients.

MAIN OUTCOME MEASURES

Lymph vessels ran parallel and interlaced with jejunal arteries. Lymphatic clearance was minimal at the jejunal artery's origin, radially spreading thereafter. Jejunal arteries were categorized into 3 groups based on position to the middle colic artery origin on 3-dimensional CT: group A: jejunal artery origins lie cranially and caudally to the middle colic artery; group B: jejunal artery origins lie caudal to the middle colic artery; and group C: jejunal artery origins lie cranial to the middle colic artery. Jejunal veins were classified into 3 groups based on their trajectories to the superior mesenteric artery (dorsally/ventrally/combined).

RESULTS

Lymph vessel clearances were 1.5 ± 1.0 mm at jejunal artery origins. Group A was present in 81 cases (80.2%), group B in 13 cases (12.9%), and group C in 7 cases (6.9%). Jejunal artery median was 4. Fifty-seven jejunal veins (56.4%) ran dorsally to the superior mesenteric artery, 16 (15.8%) ran ventrally, and 28 (27.8%) had a combined course.

LIMITATIONS

Lymph nodes were not counted during dissection because the main observation was the position of lymph vessels.

CONCLUSIONS

Minimal jejunal artery lymphatic clearance implies ligating tumor-feeding vessels at the origin. The intermingled jejunal artery lymphatics imply lymph node dissection along the proximal and distal vessels to the level of the first arcade. Classifying jejunal arteries and veins could simplify the anatomy for surgeons. See Video Abstract.

CLINICAL TRIAL REGISTRATION NUMBER

NCT05670574.

LA ANATOMA LINFTICA Y VASCULAR DEL YEYUNO DEFINE LOS PRINCIPIOS QUIRRGICOS PARA EL TRATAMIENTO DE LOS TUMORES DEL YEYUNO

ANTECEDENTES:El yeyuno tiene un amplio campo de drenaje linfático, lo que dificulta la cirugía radical.OBJETIVO:Extrapolar los resultados de dos metodologías para definir los aclaramientos linfáticos de la arteria yeyunal y las formas de los haces linfovasculares para la cirugía radical de conservación intestinal.DISEÑO:Dos estudios de cohorte.ESCENARIO:El primer conjunto de datos comprendía disecciones de cadáveres en la Universidad de Ginebra. El segundo conjunto de datos incorporaba reconstrucciones vasculares preoperatorias por TC 3D de pacientes incluidos en el ensayo clínico "Cirugía con mesenterectomía extendida (D3) para tumores del intestino delgado".PACIENTES:Se disecaron ocho cadáveres. El conjunto de datos de TC 3D incluía 101 pacientes.PRINCIPALES MEDIDAS DE VALORACIÓN:Los vasos linfáticos discurrían paralelos y se entrelazaban con las arterias yeyunales. El aclaramiento linfático era mínimo en el origen de la arteria yeyunal, extendiéndose radialmente a partir de allí. Las arterias yeyunales se clasificaron en tres grupos según su posición respecto del origen de la arteria cólica media en la TC tridimensional. Grupo A: los orígenes de la arteria yeyunal se encuentran craneal y caudalmente respecto de la arteria cólica media; Grupo B: los orígenes de la arteria yeyunal se encuentran caudalmente respecto de la arteria cólica media; Grupo C: los orígenes de la arteria yeyunal se encuentran cranealmente respecto de la arteria cólica media. Las venas yeyunales se clasificaron en tres grupos según sus trayectorias hacia la arteria mesentérica superior (dorsal/ventral/combinada).RESULTADOS:Los espacios libres de los vasos linfáticos fueron de 1,5+1,0 mm en los orígenes de la arteria yeyunal. El grupo A estuvo presente en 81 (80,2 %), el grupo B en 13 (12,9 %), el grupo C en 7 (6,9 %) casos. La arteria yeyunal tenía una mediana de 4. Un 57 (56,4 %) de las venas yeyunales discurrían dorsalmente a la arteria mesentérica superior, 16 (15,8 %) discurrían ventralmente y 28 (27,8 %) tenían un trayecto combinado.LIMITACIONES:No se contaron los ganglios linfáticos durante la disección porque la observación principal era la posición de los vasos linfáticos.CONCLUSIÓN:La mínima limpieza linfática de la arteria yeyunal implica la ligadura de los vasos que alimentan el tumor en el origen. Los vasos linfáticos de la arteria yeyunal entremezclados implican la disección de los ganglios linfáticos a lo largo de los vasos proximales y distales hasta el nivel de la primera arcada. La clasificación de las arterias y venas yeyunales podría simplificar la anatomía para los cirujanos. (Traducción-Ingrid Melo )NÚMERO DE ENSAYO CLÍNICO:NCT05670574.

Efficacy of laparoscopic low anterior resection for colorectal cancer patients with 3D-vascular reconstruction for left coronary artery preservation

BACKGROUND

Laparoscopic low anterior resection (LLAR) has become a mainstream surgical method for the treatment of colorectal cancer, which has shown many advantages in the aspects of surgical trauma and postoperative rehabilitation. However, the effect of surgery on patients' left coronary artery and its vascular reconstruction have not been deeply discussed. With the development of medical imaging technology, 3D vascular reconstruction has become an effective means to evaluate the curative effect of surgery.

AIM

To investigate the clinical value of preoperative 3D vascular reconstruction in LLAR of rectal cancer with the left colic artery (LCA) preserved.

METHODS

A retrospective cohort study was performed to analyze the clinical data of 146 patients who underwent LLAR for rectal cancer with LCA preservation from January to December 2023 in our hospital. All patients underwent LLAR of rectal cancer with the LCA preserved, and the intraoperative and postoperative data were complete. The patients were divided into a reconstruction group (72 patients) and a nonreconstruction group (74 patients) according to whether 3D vascular reconstruction was performed before surgery. The clinical features, operation conditions, complications, pathological results and postoperative recovery of the two groups were collected and compared.

RESULTS

A total of 146 patients with rectal cancer were included in the study, including 72 patients in the reconstruction group and 74 patients in the nonreconstruction group. There were 47 males and 25 females in the reconstruction group, aged (59.75 ± 6.2) years, with a body mass index (BMI) (24.1 ± 2.2) kg/m2, and 51 males and 23 females in the nonreconstruction group, aged (58.77 ± 6.1) years, with a BMI (23.6 ± 2.7) kg/m2. There was no significant difference in the baseline data between the two groups (P > 0.05). In the submesenteric artery reconstruction group, 35 patients were type I, 25 patients were type II, 11 patients were type III, and 1 patient was type IV. There were 37 type I patients, 24 type II patients, 12 type III patients, and 1 type IV patient in the nonreconstruction group. There was no significant difference in arterial typing between the two groups (P > 0.05). The operation time of the reconstruction group was 162.2 ± 10.8 min, and that of the nonreconstruction group was 197.9 ± 19.1 min. Compared with that of the reconstruction group, the operation time of the two groups was shorter, and the difference was statistically significant (t = 13.840, P < 0.05). The amount of intraoperative blood loss was 30.4 ± 20.0 mL in the reconstruction group and 61.2 ± 26.4 mL in the nonreconstruction group. The amount of blood loss in the reconstruction group was less than that in the control group, and the difference was statistically significant (t = -7.930, P < 0.05). The rates of anastomotic leakage (1.4% vs 1.4%, P = 0.984), anastomotic hemorrhage (2.8% vs 4.1%, P = 0.672), and postoperative hospital stay (6.8 ± 0.7 d vs 7.0 ± 0.7 d, P = 0.141) were not significantly different between the two groups.

CONCLUSION

Preoperative 3D vascular reconstruction technology can shorten the operation time and reduce the amount of intraoperative blood loss. Preoperative 3D vascular reconstruction is recommended to provide an intraoperative reference for laparoscopic low anterior resection with LCA preservation.

Drainage pattern of the splenic flexure vein and its accompanying arteries using three-dimensional computed tomography angiography: a single-centre study of 600 patients

AIM

The splenic flexure has variable vascular anatomy, and the details of the venous forms are not known. In this study, we report the flow pattern of the splenic flexure vein (SFV) and the positional relationship between the SFV and arteries such as the accessory middle colic artery (AMCA).

METHODS

This was a single-centre study using preoperative enhanced CT colonography images of 600 colorectal surgery patients. CT images were reconstructed into 3D angiography. SFV was defined as a vein flowing centrally from the marginal vein of the splenic flexure visible on CT. AMCA was defined as the artery feeding the left side of the transverse colon, separate from the left branch of the middle colic artery.

RESULTS

The SFV returned to the inferior mesenteric vein (IMV) in 494 cases (82.3%), the superior mesenteric vein in 51 cases (8.5%) and the splenic vein in seven cases (1.2%). The AMCA was present in 244 cases (40.7%). The AMCA branched from the superior mesenteric artery or its branches in 227 cases (93.0% of cases with existing AMCA). In the 552 cases in which the SFV returned to the IMV, superior mesenteric vein or splenic vein, the left colic artery was the most frequent artery accompanying the SFV (42.2%), followed by the AMCA (38.1%) and the left branch of the middle colic artery (14.3%).

CONCLUSIONS

The most common flow pattern of the vein in the splenic flexure is from the SFV to IMV. The SFV is frequently accompanied by the left colic artery or AMCA.

The impact of three-dimensional reconstruction and standardised CT interpretation (AMIGO) on the anatomical understanding of mesenteric vascular anatomy for planning complete mesocolic excision surgery: A randomised crossover study

BACKGROUND

Preoperative planning is a crucial aspect of safe complete mesocolic excision (CME) surgery. 3D models derived from imaging may help improve anatomical understanding of the complex vascular anatomy. Here, we assessed the effect of 3D models on surgeons' anatomical understanding in comparison to a systematic approach for CT scan interpretation (AMIGO).

METHOD

Fifteen cases were included in the study. Two GI radiology consultants reviewed each scan to ascertain the vascular anatomy. Virtual 3D models were produced and displayed on a web-based platform (https://skfb.ly/6OZUZ). A total of 13 surgical trainees were recruited. Candidates were assessed after baseline anatomical training and subsequently using the AMIGO method and 3D models. Five cases were randomly allocated in each round of testing for each participant. The primary outcome measure was an objective vascular anatomy knowledge score. The secondary outcome measure was subjective feedback from participants.

RESULTS

Both 3D and AMIGO significantly improved anatomical understanding in comparison to baseline testing. However, 3D was superior to AMIGO (3D [n = 65; median score 8/14] vs. AMIGO [n = 65; median score 6/14; p < 0.0001]. For 13/15 patient cases examined, 3D was superior to the AMIGO method. Eleven participants demonstrated better anatomical understanding using 3D models versus AMIGO. Ten participants preferred 3D models in comparison to standard CT imaging.

CONCLUSIONS

3D models improve anatomical understanding of mesenteric vascular anatomy in a group of colorectal surgical trainees in comparison to a formal CT interpretation method. 3D models may be a useful planning adjunct to 2D imaging for CME surgery.

Three-Dimensional Reconstruction of Pacemaker Lead Trajectory From Orthogonal Chest X-Rays: A Proof of Concept

Understanding the lead trajectory is important in preventing complications after cardiac rhythm device implantation. In this report, we sought to reconstruct the three-dimensional (3D) shape of a pacing lead from radiographs taken at 90-degree angles. All image data were obtained from a 65-year-old male patient, who underwent pacemaker implantation at our hospital due to third-degree atrioventricular block in 2016. Both frontal and lateral chest X-rays were taken just after the device implantation (supine position) and on the post-procedural day 1 (upright position), respectively. Fluorine-18-fluorodeoxyglucose positron emission tomography/CT was performed 75 days after the pacemaker implantation for the diagnosis of cardiac sarcoidosis. Contours of the ventricular leads were manually traced in each X-ray image and saved as Scalable Vector Format (SVG) files using the GNU Image Manipulation Program (GIMP). The 3D reconstruction was performed on Blender 2.93, which is an open-source computer graphics software. The lead trajectory could be reconstructed from bidirectional radiographs, which may allow for further investigation of the 3D shape change of the pacemaker leads.

Surgical anatomy of the accessory middle colic artery: a meta-analysis with implications for splenic flexure cancer surgery

AIM

Surgical resection of splenic flexure cancers (SFCs) is technically demanding due to the complex regional anatomy, characterized by the presence of embryological adhesions, close proximity to the pancreas and spleen, and a highly heterogeneous arterial supply and lymphatic drainage. The accessory middle colic artery (AMCA) is increasingly being recognized as an important source of blood supply to the splenic flexure. The aim of this study is to determine the prevalence and anatomical features of the AMCA.

METHOD

A systematic search of the scientific literature was conducted on PubMed and Embase from inception to November 2020 to identify potentially eligible studies. Data were extracted and prevalence was pooled into a meta-analysis using MetaXL and Meta-Analyst software.

RESULTS

A total of 16 studies (n = 2203 patients) were included. The pooled prevalence (PP) of the AMCA was 25.4% (95% CI 18.1-33.4). Its prevalence was higher in patients without a left colic artery (LCA) (PP = 83.2%; 95% CI 70.4-93.1). The commonest origin for the AMCA was the superior mesenteric artery (PP = 87.9%; 95% CI 86.4-90.7). The AMCA shared a common trunk/gave rise to pancreatic branches in 23.1% of cases (95% CI 15.3-31.9).

CONCLUSION

The AMCA contributes to the vascularization of the splenic flexure in approximately 25% of individuals, and may be an important feeder artery to SFCs, especially in the absence of a LCA. Preoperative identification of this artery is important to ensure optimal surgery for SFC and minimize complications.

Navigating the mesentery: Part III. Unusual anatomy of ileocolic vessels

AIM

The ileocolic vessels are important landmarks in advanced surgery of the midgut. The aim of the present study is to present variations of ileocolic vessels relevant to complete mesocolic excision with D3 lymphadenectomy of the right colon, within their detailed and precise morphometric framework and deriving from a large and consistent series of operated patients.

METHODS

An ongoing prospective trial 'Safe Radical D3 Right Hemicolectomy for Cancer through Preoperative Biphasic Multidetector Computed Tomography Angiography' was reviewed. The imaging datasets underwent manual segmentation and 3D reconstruction, and the results were validated at surgery. A total of 356 patients were included in the study.

RESULTS

A cross-section of the series revealed five cases (1.4%) with variation of ileocolic vessels relevant to complete mesocolic excision or D3 extended mesenterectomy. There were two cases with absence of a true classical ileocolic artery, two cases with absence of a true classical ileocolic vein, and one case of precocious bifurcation of the ileocolic artery, left to the superior mesenteric vein. The entire D3 area in all the cases was thoroughly documented and analysed from the morphometric point of view (calibres, lengths of vessels, crossing patterns).

CONCLUSION

The preoperative visualization of a patient's individual 3D anatomy is a powerful tool in identifying the variations whose negligence could have dire consequences in complete mesocolic excision of the right colon.

Value of the surgeon's sightline on hologram registration and targeting in mixed reality

Purpose

Mixed reality (MR) is being evaluated as a visual tool for surgical navigation. Current literature presents unclear results on intraoperative accuracy using the Microsoft HoloLens 1^®. This study aims to assess the impact of the surgeon’s sightline in an inside-out marker-based MR navigation system for open surgery.

Methods

Surgeons at Akershus University Hospital tested this system. A custom-made phantom was used, containing 18 wire target crosses within its inner walls. A CT scan was obtained in order to segment all wire targets into a single 3D-model (hologram). An in-house software application (CTrue), developed for the Microsoft HoloLens 1, uploaded 3D-models and automatically registered the 3D-model with the phantom. Based on the surgeon’s sightline while registering and targeting (free sightline /F/or a strictly perpendicular sightline /P/), 4 scenarios were developed (FF-PF-FP-PP). Target error distance (TED) was obtained in three different working axes-(XYZ).

Results

Six surgeons (5 males, age 29–62) were enrolled. A total of 864 measurements were collected in 4 scenarios, twice. Scenario PP showed the smallest TED in XYZ-axes mean = 2.98 mm ± SD 1.33; 2.28 mm ± SD 1.45; 2.78 mm ± SD 1.91, respectively. Scenario FF showed the largest TED in XYZ-axes with mean = 10.03 mm ± SD 3.19; 6.36 mm ± SD 3.36; 16.11 mm ± SD 8.91, respectively. Multiple comparison tests, grouped in scenarios and axes, showed that the majority of scenario comparisons had significantly different TED values (p < 0.05). Y-axis always presented the smallest TED regardless of scenario tested.

Conclusion

A strictly perpendicular working sightline in relation to the 3D-model achieves the best accuracy results. Shortcomings in this technology, as an intraoperative visual cue, can be overcome by sightline correction. Incidentally, this is the preferred working angle for open surgery.