A 51 year-old male presented with a 2 month history of a 2.5 × 3.5 cm left gingival squamous cell carcinoma. On physical exam, the left mandible was involved as were multiple ipsilateral lymph nodes. The largest of which was 3 × 3 cm. The contrast-enhanced MRI scan in the maxillofacial region is shown in Fig. a. We used CAD/CAM technology to assist with surgical planning (Fig. b, c), then we used plastic and a resin composite material for rapid prototyping through the 3D printer (Fig. d-g). We developed an equiratio 3D anatomical model and osteotomy plate. The patient underwent segmental mandibulectomy with free fibula reconstruction (Fig. h). The fibula osteotomies on the pedicle vascularized free fibular flap were cut according to the preoperative simulation (Fig. g). A custom pre-bent plate was designed according to the computer simulation and the 3D model. We fixed the custom titanium plate at a predetermined position according to the simulation data and 3D model, and the oral defect was simultaneously repaired by the soft tissue component of the flap (Fig. i, k).\nPost-operatively the reconstruction did well. The patient was followed up with good facial morphology and postoperative CT imaging showed good contour of the fibula. The fixation position of titanium plate screws were accurate (Fig. l), and the occlusion was normal (Fig. m).
A 17-year-old female patient was admitted to the hospital on September 9, 2019 with abdominal pain that had lasted for half a year and had been worsening for half a month.\nOn September 8, 2019, the patient visited Xiamen Third Hospital for an abdominal US. A homogeneous mass with fluid echo was detected in the left middle abdomen that was suspected as being a retroperitoneal tumor. The patient came to our hospital for further diagnosis and treatment.\nThe patient was in good health with no history of infectious disease, allergy, or surgery.\nThe patient has no family or genetic history of disease.\nA standard physical examination was performed. The abdomen was flat and soft; there was tenderness on the left side but no rebound tenderness and no Murphy’s sign. The mass in the left middle abdomen was about 8 cm × 10 cm in size, with an intact capsule but without a distinct boundary; the mass showed poor mobility with tenderness elicited in the palpation test. The liver and spleen were impalpable under the ribs, and there were no obvious gallbladder abnormalities. Further physical examination revealed drum sounds on percussion, negative shifting dullness, and normal bowel sounds on auscultation.\nNo abnormalities were found in the routine blood, urine and stool analysis, or liver and kidney function.\nA clinical examination after admission on September 9, 2019 revealed sinus arrhythmia by electrocardiography, and a pulmonary nodule in the right lower lobe by helical CT that may have been an old pulmonary lesion. Abdominopelvic enhanced helical CT showed a retroperitoneal space-occupying lesion in the upper left quadrant of the abdomen that was presumed to be retroperitoneal liposarcoma or teratoma (Figure ).\nWe used the proprietary XMQB-Liver software (Xiamen Qiangben Technology Co, Xiamen, China) for 3D reconstruction of CT images. The software allowed rotation, blurring, and elimination of elements in the 3D model (Figure ), provided omnidirectional views (Figure and ), and allowed tumor virtualization (Figure ), removal of normal organs, and observation of the relationship between the tumor, blood vessels, and surrounding organs (Figure ). The tumor was located in the upper left retroperitoneum and was about 11.3 cm × 9.1 cm in size with well-defined borders; it compressed the left renal artery and vein, resulting in vascular displacement and deformation. The inferior vena cava and abdominal aorta were unaffected. The left kidney and adrenal gland were shifted forward and downward under pressure; there was no visible invasion of the liver, spleen, pancreas, or stomach. The intestines could not be reconstructed.