Application of computer-assisted surgery system in a child with multiple traumas: a case report

Abstract

Background

Severe traumatic liver rupture in children has a high mortality rate. The computer-assisted surgery (CAS) system is an effective medical image simulation tool, which can display the adjacent relationship between the liver and surrounding tissues (especially compressed blood vessels) in a three-dimensional (3D), dynamic and complete way, and assist in precise liver resection. It provides important guidance for preoperative planning and intraoperative navigation. This chapter reports the individualized computer-assisted surgical planning and progress of a case of complex pediatric abdominal trauma.

Case Description

A 3-year-old girl was admitted to the hospital due to a severe abdominal crush injury caused by a car accident. Contrast-enhanced computed tomography (CT) showed grade V liver injuries [2018 American Association for the Surgery of Trauma-Organ Injury Scale (2018 AAST-OIS)], as well as splenic and renal contusion. Emergency CAS was performed to repair liver contusion. Biliary fluid was drained from the chest cavity after the operation, and contrast-enhanced CT showed diaphragmatic rupture and intrahepatic pseudoaneurysm. The ruptured diaphragm was repaired by laparotomy with the assistance of a Hisense CAS system, and the intrahepatic pseudoaneurysm was treated by interventional therapy. The child responded well to the comprehensive treatment, and no complications such as bile leakage and infection were found after the operation. Regular imaging and laboratory tests confirmed that the child recovered stably, and the child displayed satisfactory physical development and growth during the follow-up period.

Conclusions

The CAS system can predict surgical risk, and has important clinical value for in the treatment of children with multiple traumas.

Introduction

After severe abdominal trauma, the hemodynamic status of children changes quickly, the ability to tolerate hemodynamic stress is poor, and the circulating blood volume is small; especially when liver, spleen, and large blood vessel rupture and bleeding occur, hemorrhagic shock can easily ensue. Computed tomography (CT) examination has important diagnostic value for the location, extent, and degree of liver rupture (1). However, it is sometimes difficult for conventional CT to accurately show the degree of vascular involvement in liver laceration, and it is also difficult to determine the degree of portal vein dominance and hepatic vein reflux in the liver. Compared with adults, children have immature organs, thin blood vessels, and poor surgical tolerance, so it is difficult to perform precise hepatectomy. The computer-assisted surgery (CAS) system has been increasingly used in clinical surgical treatment, due to its advantages of three-dimensional (3D) visualization (2), accurate vascular reconstruction in children (3,4), 3D model surgical simulation (3), 3D data automatic calculation (4,5), and so on. This report explores the application of CAS in precise surgical resection of liver rupture in children. We present this article in accordance with the CARE reporting checklist (available at https://qims.amegroups.com/article/view/10.21037/qims-24-1862/rc).

Case presentation

A 3-year-old Chinese female was admitted to an emergency department with abdominal pain for half-a-day after being crushed during a car accident. Half a day ago, the child had been sent to a local hospital for treatment due to abdominal compression caused by a car, without obvious trauma and bleeding after injury. Emergency chest total abdominal pelvic CT showed grade V liver injuries [2018 American Association for the Surgery of Trauma-Organ Injury Scale (2018 AAST-OIS)], and she was transferred to The Affiliated Hospital of Qingdao University immediately after symptomatic and supportive treatment. The child was born at full term, with normal intellectual development and timely achievement of developmental milestones, and no significant past medical history. The child had no history of infection such as hepatitis and tuberculosis. There was no history of surgery, trauma, or allergy. Vaccination had been carried out as planned. The parents were healthy and had no familial history of metabolic and infectious diseases. Physical examination revealed a temperature of 38 ℃; pulse of 148 beats/min; blood pressure of 103/72 mmHg; full consciousness; pale face; pale mucosa, lip, and nail beds; and patchy ecchymosis on the right lower back. Her breath showed tachypnea, and the lungs were clear on percussion. The abdomen was distended and symmetrical, with tense muscles and tenderness throughout. Abdominal percussion revealed a drum sound and reduced bowel sounds. Laboratory tests showed that white blood cell count was 10.47×10⁹/L, neutrophil count was 8.45×10⁹/L, platelet count was 102×10⁹/L, and lymphocyte count was 1.25×10⁹/L. Contrast-enhanced CT examination (Figure 1A-1D) revealed large low-density areas without enhancement in the right lobe and the medial segment of the left lobe (①), a small patchy focal hypodense area at the posterior margin of the spleen (②), a large amount of fluid density shadow in the abdominal cavity and pelvic cavity (③), and the parenchymal fissure of the left renal outer margin having a low-density area without enhancement (④). The diaphragm was continuous and complete (Figure 1E-1G).

Figure 1.

Contrast-enhanced CT images of the abdomen of the child showed grade V liver injuries according to the revised 2018 AAST-OIS. ①②③④ are the positions indicated by red, green, yellow, and blue arrows, respectively. (A) Preoperative arterial phase images with axial enhanced CT of the abdomen showed more than 75% destruction of the right lobe and medial segment of left lobe (①), subcapsular hematoma at the posterior margin of the spleen (②) and a large fluid density shadow in the abdominal cavity (③) were also noted. (B,C) Preoperative venous phase images with axial enhanced CT of the abdomen showed contusion and laceration of parenchyma at the external margin of left kidney (④). (D) Preoperative delayed phase images. (E) Axial contrast-enhanced CT of the abdomen. (F) Coronal contrast-enhanced CT of the abdomen. (G) Sagittal contrast-enhanced CT of the abdomen. AAST-OIS, American Association for the Surgery of Trauma-Organ Injury Scale; CT, computed tomography.

The diagnosis was multi-organ abdominal injury: hepatic, splenic, and renal lacerations (left). There was a large amount of hemorrhagic fluid and ascites in the abdominal cavity and a small amount of pleural effusion. Version V4 of Hisense CAS (Hisense, Qingdao, China) was applied for image processing. The Digital Imaging and Communications in Medicine (DICOM) files were imported into the Hisense CAS system, and the 3D reconstruction was then performed (Figure 2A-2D). The CAS system could use the 3D images to directly observe the adjacent relationship between the liver contusion and the surrounding organs and blood vessels. The surgeon was able perform surgical simulation resection on the 3D model and obtain different surgical schemes, so as to determine the optimal and personalized surgical scheme (Figure 2E,2F).

Figure 2.

Following the 3D reconstruction using Hisense CAS, the location and extent of liver contusion were precisely visualized through its semi-transparent functionality. (A) Hisense CAS frontal image of liver contusion and surrounding organs. (B) Hisense CAS frontal image of liver contusion and surrounding organs after semi-transparent liver. (C) Hisense CAS back image of liver contusion and surrounding organs. (D) Hisense CAS back image of liver contusion and surrounding organs after semi-transparent liver. (E,F) Computer-assisted liver rupture resection. (G,H) Intraoperative pictures showing hepatic contusion (grey arrow). (I) The appearance of liver after hepatic contusion was repaired during operation. (J) The remaining liver was fixed to the deltoid ligament. 3D, three-dimensional; CAS, computer-assisted surgery.

According to the results of contrast-enhanced CT and 3D reconstruction, parenchymal rupture affected more than 75% of the right liver lobe (Video 1). According to the assessment criteria of grade 5 V trauma established by the 2018 AAST-OIS, the degree of liver injury in this child was at least grade V, which met the indications for surgery (1). Intraoperatively, the amount of blood in the abdominal cavity was approximately 300 mL. Rapid abdominal exploration and hilar clamping were performed. Following laparotomy, a gastrointestinal decompression tube was placed under direct visualization to reduce gastrointestinal distension and monitor for potential bile leakage, given the severity of hepatic injury. Exploration revealed fragmentation of the 6th and 7th segments of the right lobe of the liver. The right anterior and posterior branches of the portal vein were intact. The intraoperative exploration was completely consistent with the preoperative 3D evaluation. The 6th and 7th segments of the right lobe of the liver were excised, debrided, and sutured, according to plan. Areas of ischemic necrosis in the 6th and 7th segments of the right lobe were resected. The remaining tissue in the right lobe was examined again for significant necrosis or ischemia, and the blood supply was deemed to be good. Therefore, we decided to retain the remaining tissue (Figure 2G-2J). The liver section was sutured to stop bleeding and blocked for 15 minutes. The surgeon explored the spleen and found a subdorsal splenic hematoma without active bleeding, so he decided not to treat it for the time being. The surgeon explored the left perirenal fat sac and perirenal fascia for hematuria, and a decision was made to place a perirenal drainage tube. The operation was well tolerated with no immediate complications.

Video 1.

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Hisense CAS and axial CT image video showed multiple trauma. CAS, computer-assisted surgery; CT, computed tomography.

Three days postoperatively, 232 mL of a light-green fluid was drained from the gastrointestinal decompression tube, and 40 mL of a light-red bloody fluid was drained from the abdominal cavity, but the child exhibited dyspnea and tachypnea (Figure 3A). Ultrasound-guided puncture and tube drainage of the right thorax were performed, and 363 mL of yellow-green fluid was drained. Three days after puncture, 200 mL of a pale, bile-like, yellow-green fluid was still drained from the thorax daily due biliary leakage.

Figure 3.

Abdominal contrast-enhanced CT images of the child. ①②③④⑤⑥ are the positions of red, yellow, pink, green, blue, and orange arrows, respectively. (A) A pulmonary window image of chest CT showing a pleural effusion on the right (①) with compression atelectasis (②) with a wrapped pneumothorax on the right (③) and inflammation or bleeding on the left (④). (B) A mediastinal window image of chest CT. (C) A liver hemangioma image showing hepatic artery portal vein fistula with pseudoaneurysm formation (⑤). (D) The axial plane image of the right diaphragm rupture (⑥). (E) The coronal plane image of the right diaphragm rupture (⑥). (F) The sagittal plane image of the right diaphragm rupture (⑥). (G) Front view of the upper and lower abdomen. (H) Back view of the upper and lower abdomen. (I) Front view of atelectasis. (J) Back view of atelectasis. (K) Front view of a diaphragm rupture. (L) Back view of a diaphragm rupture. (M) Front view of the liver pseudoaneurysm (white arrow). (N) Blood vessel course of the pseudoaneurysm. CT, computed tomography.

Contrast-enhanced CT was repeated (Figure 3A-3F), revealing massive pleural effusion (①) and compressive atelectasis (②) on the right side. The right pleural cavity contained fluid and an encapsulated pneumothorax, raising suspicion of a loculated pneumothorax with associated pleural effusion (③). The lung’s left lower lobe was patchy and enhanced (④). Abnormal cystic enhancement of the medial segment of the liver’s left lobe and abnormal enhancement of the left branch of the hepatic artery and portal vein were considered indicative of hepatic artery portal vein fistulas with pseudoaneurysm formation (⑤) and right diaphragm rupture (⑥). Preoperative 3D reconstruction was performed again to guide surgical planning (Figure 3G-3N). The diaphragmatic rupture was directly opposite the hepatic contusion repair site (Video 2). CAS clearly showed the extent of pleural effusion, the degree of atelectasis, and the location of diaphragmatic rupture, and helped the surgeon to plan the operation in advance.

Video 2.

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Hisense CAS and axial CT image video showed the location of diaphragmatic rupture and intrahepatic pseudoaneurysm. CAS, computer-assisted surgery; CT, computed tomography.

The patient underwent exploratory laparotomy, right diaphragm repair, and right thoracic closed drainage. The original incision was reopened in the abdomen, and bilious fluid was found in the abdominal cavity. Exploration of the right diaphragm revealed a tear approximately 8 mm in diameter of the right diaphragm near the spine, which we repaired. However, the intrahepatic pseudoaneurysm was larger than before (Figure 4A), and interventional treatment was performed.

Figure 4.

Imaging data of the child undergoing interventional therapy. (A,B) Intrahepatic pseudoaneurysm (blue arrow). (C) The pseudoaneurysm was successfully treated by interventional embolization (blue arrow). (D) Postoperative ultrasound showed that the hepatic artery and portal vein were unobstructed.

A pediatric cannula needle was used to enter the right femoral artery (Figure 4). The 4F vascular sheath was placed after successful entry. A 4F pigtail catheter was cannulated into the descending aorta. Angiography showed that the proper hepatic artery originated from the superior mesenteric artery, and a tortuously dilated artery emanated from the left hepatic artery. At the distal end of the artery, contrast agent stagnation and overflow were observed, forming a cystic high-density area, with the contrast agent disappearing slowly. Seven Cook coils (Cook Medical, Bloomington, IN, USA) were inserted into the pseudoaneurysm by inserting a microcatheter. Postoperative ultrasound showed that the hepatic artery and portal vein were well patent. The child recovered with no complications with subsequent good development and growth.

Ethical considerations

All procedures performed in this study were in accordance with the ethical standards of the institutional and/or national research committee(s) and with the Declaration of Helsinki and its subsequent amendments. Written informed consent was obtained from the patient’s legal guardian for publication of this case report, accompanying images and videos. A copy of the written consent is available for review by the editorial office of this journal.

Discussion

The Hisense CAS was developed by Prof. Dong’s group in 2013 (6,7). This system can perform medical image preprocessing with CT images stored in DICOM format that can be enhanced in high definition before preprocessing. The medical images labeled with features such as greyscale and texture features are then subjected to deep machine learning by convolutional networks for biomedical image segmentation (U-Net) on a large number of standard DICOM files (8). On a large dataset of DICOM-standardized abdominal CT scan images, the two-dimensional images were segmented into distinct regions based on characteristics such as gray level, texture, and vascular physiological features (9). This process enabled the precise identification of boundaries, including the outer edges of organs, tumors, lesions, and blood vessels. The contusion regions of the lung, bronchus, esophagus, heart, blood vessels, and liver were sequentially extracted using a rapid segmentation algorithm. The hepatic contusions were automatically annotated on the transverse plane and subsequently segmented across different sections of the coronal and sagittal planes to generate visualized 3D images of liver injuries. These images were then integrated to produce interactive 3D reconstructions. The course of vessels and their spatial relationship with the hepatic contusions were accurately depicted. Thus, automatic and accurate segmentation of new input data can be achieved. 3D imaging technology based on CT images is able to display the positional relationships of the liver, hepatic contusions, and all internal ductal structures in a comprehensive and simultaneous manner to achieve accurate evaluations of distances in 3D space, which has obvious advantages in vessels (the portal vein, hepatic artery, and hepatic vein) with compression deformation or individual anatomical variations. The ability to track the route of each vessel and determine the drainage segment of each vein is important for determining individualized liver segmental anatomy (10,11). This means surgeons can observe the morphology of liver parenchymal disruptions in an all-round, 3D, and intuitive way and can assist in guiding accurate liver surgery before and during the operation (12,13). Comparative studies have confirmed that the utilization of a CAS system in pediatric hepatic procedures enhances lesion resection rates, decreases operative duration, reduces intraoperative blood loss, shortens hospitalization periods, and improves surgical safety (4). By constructing a personalized digital 3D liver model, the surgeon can conduct preoperative planning and assess the feasibility of the surgical plan through calculating the functional remnant liver volume. This process enables the determination of the optimal surgical strategy. In this case, partial resection of the liver’s right lobe with the assistance of CAS can accurately maximize liver protection, ensure the anatomical integrity of the remaining liver, and maximize the retention of functional volume, which aligns with the concept of accurate hepatectomy (6,14).

After the crush injury of the patient, the local contusion gradually became necrotic, forming a defect. The rupture of the diaphragm was directly opposite the suture of the hepatic contusion and laceration after liver repair was completed. In general, the rupture of small bile ducts in a liver wound would not leak bile. However, the bile from the tiny bile ducts in the liver wound continued to be sucked into the chest because of diaphragm rupture and the negative pressure of local suction with each breath. Consequently, the chest gradually accumulated a large amount of bile fluid and compression atelectasis. Diaphragmatic rupture cannot heal itself (15) and surgical treatment should be performed if the diagnosis is clear and there are no contraindications (16). Performing a second operation through the original incision site can reduce secondary trauma, improving recovery.

Abdominal trauma resulted in the rupture of the local branches of the left hepatic artery, accompanied by damage to the branches of the main and portal veins. Blood flow from the hepatic artery was blocked, and venous return gradually accumulated into a pseudoaneurysm. It was essential that the right lobe was not completely removed during the first operation. The preservation of right liver tissue ensures normal blood flow to the liver and improves the survival rate in children. Therefore, preoperative 3D reconstruction is important for accurately determining whether and how much right liver lobectomy is needed. It provides a basis for making a reliable and personalized surgical plan before surgery and improves the safety and accuracy of the operation. Presently, selective hepatic arterial angiography is considered an important examination method for traumatic hepatic pseudoaneurysms (17) and selective hepatic artery embolization is the gold standard for their diagnosis and treatment (18). During follow-up, the patient remained in good health, with no abdominal discomfort or other complications. According to the patient’s parents, the child has fully regained normal physical function and daily activity levels. No persistent psychological or emotional disturbances have been observed. The family expressed a high level of satisfaction with the surgical outcome and long-term recovery. The abdominal surgical scar has significantly faded, and routine follow-up examinations, including liver function tests, have shown no abnormalities or delayed complications. The family emphasized the importance of timely intervention and preoperative planning under CAS support in the management of pediatric trauma.

Conclusions

Computer-assisted medical technologies synergistically combine advanced imaging modalities, analytical algorithms, and computational modeling to optimize clinical decision-making and surgical simulation. The CAS system marks a significant leap forward in contemporary medical innovation. Particularly in pediatric surgery, these innovations play a crucial role in improving patient safety, leveraging artificial intelligence to provide real-time insights and predictive capabilities. In future, the development of tailored, 3D surgical planning tools could redefine how precision medicine is applied in surgical interventions, offering more personalized and effective treatment options.

Supplementary

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Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. All procedures performed in this study were in accordance with the ethical standards of the institutional and/or national research committee(s) and with the Declaration of Helsinki and its subsequent amendments. Written informed consent was obtained from the patient’s legal guardian for publication of this case report, accompanying images and videos. A copy of the written consent is available for review by the editorial office of this journal.