Technical NoteRed cell volume measurement – using indium as a replacement for chromiumAinslie-McLaren, Gilliana; Fee, Angelaa; McKinstray, Junea; Lee, Alison B.a; Bolster, Alison A.a,,bAuthor Information aDepartment of Nuclear Medicine, Stobhill Ambulatory Care Hospital bCollege of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK Received 17 October 2019 Accepted 3 March 2020 Correspondence to Alison A. Bolster, PhD, Department of Nuclear Medicine, Lower ground floor Queen Elizabeth Building, Glasgow Royal Infirmary, Glasgow, G31 2ER, UK, Tel: +44 141 211 4762; fax: +44 141 355 1772; e-mail: email@example.com Nuclear Medicine Communications: June 2020 - Volume 41 - Issue 6 - p 589-596 doi: 10.1097/MNM.0000000000001185 Buy Metrics Abstract The withdrawal of 51Cr-chromate has meant that the technique commonly used for direct measurement of red cell volume has had to be replaced. Most centres moved to a 99mTc erythrocyte label, however, 99mTc is known to dissociate over time. We have investigated an alternative technique using an 111In-chloride and tropolone solution and tested this both in vitro and in vivo. Initial in-vitro and in-vivo work, which included a check of the stability of the radio-labelled product at one hour, demonstrated this label to be stable over this time period. To date, 20 patients have undergone this technique and results show that this technique is a viable alternative to 51Cr-chromate particularly for patients with splenomegaly who require late sampling. This procedure is now in routine use in our institution. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.