Image Registration Technique for Assessing the Accuracy of Intraoperative Osteotomy for Pelvic Tumors by 3D-Printed Patient-Specific Templates

The study aimed to explore the feasibility of an image registration technique for assessing the accuracy of intraoperative osteotomy of pelvic tumors by 3-dimensional(3D)-printed patient-specific templates.Patients with malignant pelvic tumors who were admitted to our hospital between March 2014 and December 2020 were retrospectively enrolled.Patients underwent hemi-pelvic resection and reconstruction by 3D-printed individualized prostheses.The registration between the designed model and the postoperative segmented model of the prosthesis was used to obtain the intraoperative osteotomy plane and reduce metal artifacts in postoperative computed tomography(CT)images.The distance and angle between the planned and actual osteotomy planes were then used to assess the accuracy of the intraoperative osteotomy.Eight patients with 13 osteotomy planes were enrolled,including four males and four females.The median age at the time of imaging examination was 44 years(range,33–54 years).All intraoperative osteotomy planes were assessed successfully.The mean distance between the planned and true intraoperative osteotomy planes was−0.69 cm(−7.5–7.35 cm),and the mean angle was 6.57°±3.36°(1.05°–11.88°).This new assessment method of registering the designed model and the postoperative CT segmented model of the prosthesis may be used to assess the accuracy of intraoperative osteotomy for pelvic tumors,using 3D printed patient-specific templates.

Mortality and Morbidity Following Surgery for Primary Malignant Musculoskeletal Tumors in the Pelvis and Limbs: A Retrospective Analysis Using the Japanese Diagnosis Procedure Combination Database

Introduction: Resection of malignant pelvic tumors has long been considered to be associated with higher postoperative mortality and morbidity than resection of malignant limb tumors. We compared the postoperative adverse events of pelvic tumor surgery and limb tumor surgery using a national inpatient database. Methods: We identified patients who underwent surgery for primary musculoskeletal malignant tumors of the pelvis or limbs between July and December in 2007- 2010 using the Japanese Diagnosis Procedure Combination inpatient database. We calculated the risk-adjusted odds ratio for the occurrence of postoperative complications following pelvic tumor surgery with reference to limb tumor surgery using a multivariable logistic regression analysis. Results: Of 3255 eligible patients, 3116 underwent limb tumor surgery and 139 underwent pelvic tumor surgery. In-hospital mortality was 0.6% and 0.7% and postoperative complication rates were 8.2% and 18.7%, respectively. The rate of blood transfusion and duration of anesthesia over 480 min were higher in the pelvic tumor group. Blood transfusion volume and duration of anesthesia were independently associated with worse outcomes, but there was no significant association between tumor location and occurrence of postoperative complications (odds ratio 1.18, 95% confidence interval 0.73 - 1.88, p = 0.502). Conclusions: Blood transfusion volume and duration of anesthesia were significant predictors of outcome. Our data demonstrate that the higher morbidity rate after pelvic tumor resection could result from the larger blood transfusion volume and longer anesthesia duration.

Value of contrast-enhanced ultrasound in deep angiomyxoma using a biplane transrectal probe:A case report

BACKGROUND Deep angiomyxoma(DAM)is a very rare tumor type.Magnetic resonance imaging(MRI)is considered the best imaging modality for diagnosing DAM.Computed tomography(CT)is used mainly to assess the invasion range of DAM.The value of ultrasonography in the diagnosis of DAM is still controversial.Through a literature review,we summarized the current state of ultrasonic examination for DAM and reported for the first time the contrast-enhanced ultrasound(CEUS)features of DAM seen using a biplane transrectal probe.CASE SUMMARY A 37-year-old woman presented with a sacrococcygeal mass that had gradually increased in size over the previous 6 mo.MRI and CT examinations failed to allow a definite diagnosis to be made.Transperineal core needle biopsy(CNB)guided by transrectal ultrasound and CEUS was suggested after a multidisciplinary discussion.Grayscale ultrasound of the lesion showed a layered appearance with alternating hyperechoic and hypoechoic patterns.Transrectal CEUS showed a laminated distribution of the contrast agent that was consistent with the layered appearance of the tumor on grayscale ultrasound.We performed transperineal CNB of the enhanced area inside the tumor under transrectal CEUS guidance and finally made a definitive diagnosis of DAM through histopathology.The patient underwent laparoscopic-assisted transabdominal surgery combined with transperineal surgery for large pelvic tumor resection and pelvic floor peritoneal reconstruction.No recurrence or metastasis was found at the ninemonth follow-up.CONCLUSION Transrectal CEUS can show the layered perfusion characteristics of the contrast agent,guiding subsequent transperineal CNB of the enhanced area within the DAM.