Application of Three-Dimensional Visualization Technology in Laparoscopic Surgery for Pheochromocytoma/Paraganglioma: A Single-Center Experience

Patient-specific three-dimensional-printed models for canine adrenalectomy: a report of three cases

Case history: Three dogs with adrenal masses scheduled for adrenalectomy were prospectively enrolled into a study to investigate the effectiveness of a 1:1-scale, three-dimensional (3D) printed model of neoplastic adrenal glands to aid surgical planning and provide intra-operative assistance during adrenalectomy in dogs.Case 1 presented with anorexia, lethargy and a distended abdomen; Case 2 with loss of appetite, behavioural changes, and vocalisation; and Case 3 with mild inappetence during the previous 15 days.Clinical and imaging findings: On physical examination, mild abdominal pain was noted in all cases. Case 1 was consistently mildly hypertensive over repeated measurements. All cases had mild or moderate elevations in the activities of alanine aminotransferase and aspartate aminotransferase, and the concentration of C-reactive protein. Cases 1 and 2 also had mild leucocytosis. Abdominal CT revealed a left-sided adrenal tumour with caval invasion in Case 1, and right-sided adrenal tumours without caval invasion in Cases 2 and 3. 3D-printed models were created from the CT scan. Different colours were assigned to anatomical structures for better visualisation. Measurements of six anatomical landmarks were made on CT images and on the 3D-printed model. The median absolute difference in measurements taken from the model and the CT scan was 0.75 (min 0, max 3.2) mm.Treatment and outcome: All dogs underwent surgical removal of the adrenal tumour via sterno-pubic celiotomy. Placing the 3D model on the operating table in the same orientation as the patient allowed for precise pre-planning of the dissection depth. Printed without the fat, and fibrous and capsular tissues that typically cover the retroperitoneal space, the model helped the surgeon to visualise vascular structures that were still covered by connective tissue in the patient. Subjectively, the use of 3D models improved surgical planning and execution by enhancing the understanding of anatomical relationships and enabling the accurate identification of surgical landmarks.No major intra-operative complications were reported. Post-operative outcomes were favourable, with no significant complications observed.Clinical relevance: The use of 3D-printed models in adrenal surgeries for dogs may enhance the surgeon's spatial awareness and intra-operative confidence. We recommend that these models are used in conjunction with CT imaging for effective pre-operative planning. Further research with larger sample sizes and a control group would allow a fuller exploration of the benefits of 3D-printed models in veterinary surgical practices.

Recent advances in algorithms predicting hemodynamic instability undergoing surgery for phaeochromocytoma and paraganglioma

Abdominal pheochromocytomas and paragangliomas (PPGLs) are characterized by the overproduction of catecholamines, which are associated with hemodynamic instability (HDI) during surgery. Therefore, perioperative management to prevent intraoperative HDI is imperative for the surgical treatment of PPGLs. Owing to the rarity and heterogeneous nature of these tumors, pre-surgical prediction of HDI is a clinical dilemma. The reported risk factors for HDI include perioperative preparation, genetic background, tumor conditions, body composition, catecholamine levels, and surgical approach. Additionally, several personalized algorithms or models including these factors have been developed. The first part of this review outlines the prediction models that include clinical features such as tumor size and location, body mass index (BMI), blood glucose level, catecholamine levels, and preoperative management with α-adrenoceptor blockade and crystal/colloid fluid. We then summarize recently reported models that consider additional factors such as genetic background, radiomics, robotic-assisted surgical approach, three-dimensional visualization, and machine-learning models. These findings suggest that a comprehensive model including risk factors is the most likely approach for achieving effective perioperative management.

Laparoscopic Resection of a Non-functional, Extra-adrenal Paraganglioma: A Case Report and Literature Review

Non-functional, extra-adrenal, retroperitoneal paraganglioma is a rare, neuroendocrine, and potentially malignant tumor. Its diagnosis and treatment may be challenging. A 69-year-old female patient was admitted because of a left para-aortic, solid, 4.4-cm mass, incidentally discovered during abdominal ultrasonography for screening purposes. Her clinical examination was unremarkable. Preoperative differential diagnosis based on cross-sectional imaging included tumor of neuroendocrine or mesenchymal origin. Hormonal investigation with 24-hour urinary catecholamines and metanephrines and plasma-fractionated metanephrines was in the normal range. Following consultation with the endocrinologist and anesthesiologist, the tumor was removed by using the three-dimensional (3D) laparoscopic transperitoneal surgical approach. The perioperative course was uneventful and the patient was discharged on the third postoperative day. Histopathologic findings were consistent with the diagnosis of retroperitoneal extra-adrenal paraganglioma of 5 cm in maximum diameter.