Selective Intra-Arterial Calcium Stimulation with Hepatic Venous Sampling for Preoperative Localization of Insulinomas

Abstract

ObjectiveTo determine the value of selective intra-arterial calcium stimulation with hepatic venous sampling using serum insulin and C-peptide gradients for the preoperative localization of insulinomas.Materials and MethodsSeven consecutive patients [three men and four women aged 15-77 (mean, 42.7) years] with hypoglycemia underwent selective intra-arterial calcium stimulation in conjunction with hepatic venous sampling. Insulin gradients were calculated by an individual blinded to all other preoperative imaging studies and operative findings. In all patients except one, C-peptide gradients were also analyzed. The results were compared with the preoperative findings of ultrasonography, computed tomography, arteriography and endoscopic ultrasonography, as well as with the intraoperative findings of ultrasonography and palpation at surgery.ResultsEight insulinomas (mean diameter, 12.5 mm) were diagnosed after surgery. In six patients, the calcium stimulation test with insulin gradients allowed accurate localization of the pathologic source of insulin secretion. Both C-peptide and insulin gradients substantially increased diagnostic accuracy. In one patient, C-peptide gradients were more helpful than insulin gradients for tumor localization.ConclusionSelective intra-arterial calcium stimulation with hepatic venous sampling is a highly accurate and safe method for the preoperative localization of insulinomas. Additional C-peptide gradients seem to be helpful in assessing tumor location, but further study is needed.

A novel technique in selective venous sampling in the localization of parathyroid tumours utilizing a micro-wire and standardized catheter

“…Furthermore catheter exchange over a guidewire may result in loss of position and may be time-consuming if done at several venous locations. Other well-known tricks include purposely making a side hole in the selective end-hole catheter with an 18-gauge needle prior to the procedure or advancing a micro catheter through the selective end hole catheter and aspirating through this [4]. Non-target sampling, catheter blockage and catheter damage are problems with these techniques.…”

Insulinoma of Pancreatic Head Localized by Intra-Arterial Calcium Stimulation with Hepatic Venous Sampling

“…When non-invasive modalities fail to localize the tumours, invasive modalities such as endoscopic ultrasonography (EUS), angiography, transhepatic portal venous sampling, and ASVS are utilized. Comparing these two modalities, invasive ones have higher sensitivity compare to non-invasive ones, particularly ASVS technique which is reported to be the most sensitive technique with sensitivity of over 90% (range 87.5-100%) in localization accuracy [2][3][4]7 .…”

“…Most insulinomas are solitary and small, with 90% being less than two cm 2 . Although 90% of these tumours are benign 3 , they have the potential to produce profound morbidity and risk of fatal hypoglycaemia. Insulinoma can be treated effectively by surgical excision.…”

“…Occult insulinoma refers to a biochemically proven tumour with indeterminate anatomical site before operation. Intra-arterial calcium stimulation with hepatic venous sampling (ASVS), an invasive modality, is highly accurate in the preoperative localization of insulinomas and has been shown to be superior to non-invasive localization techniques 3,4 .…”

Diagnostic value of ASVS for insulinoma localization: A systematic review and meta-analysis

“…If there are abnormal findings in routine examinations such as ultrasound, CT, and MRI, a corresponding arterial calcium stimulation in the suspected area can be performed first to reduce the possibilities of incorrect localization caused by calcium reflux due to arterial spasm. Different authors have used different calcium concentrations, and the effect of calcium concentration should also be further studied [35].…”