Abstract No. 1077. J Dent Res 2002; 81 Special Issue A (San Diego Abstracts): A-154. The possibility to treat patients with previously leading disorder, is continuously improving. Several treatments anyhow result in undesired side-effects. We have previously presented reports regarding whole salivary secretion rates showing that a reduction is found during the first year after pediatric BMT. For children treated with TBI the reduction I still persistent four years after BMT.
Scintigraphy is a method to study the functional capacity of the glands in different aspects. A gammacamera – in front of the patient head – measures the activity of injected tracer 99mm-technetium-pertechnetate that can be followed in specific regions of interest (ROI).
The data can be replayed to construct a time-activity-curve (TAC) illustrating the changes over time regarding activity in each ROI. Scintigraphic variables of specific interest are shown in this slide….
… ..and the important percentage stimulated secretion (sometimes called emptying capacity or excretion capacity) is defined as the percentage reduction of activity from maximum uptake (Ma) to minimum uptake level (Mi) after stimulation.
The objective was to study the scintigraphic functional changes over time of the parotid and submandibular glands after TBI at BMT.
Only nine of the patients invited accepted to participate in the scintigraphic study. Three patients did not want to continue the scintigraphic study after the first examination (before TBI) and one patient died before three month follow up. Making it a total of five patients participating at the three months follow up. Another two patients died before the twelve month follow up, making it only three patients completing the scintigraphic study.
The patients were treated for lymphoma, acute myeloid leukemia, chronic myeloid leukemia, acute lymphoblastic leukemia and several aplastic anemia.
The treatments included conditioning therapy with cyclophosphamide, 10 Gy TBI, and graft-versus-host (GVH)-prophylaxis with Methotrexate and Cyclosporine-A.
Unstimulated (USSR) and stimulated (SSSR) salivary secretion rates were measured during 15 and 5 minutes, respectively. Thereafter salivary gland scintigraphy (SGS) was performed during 60 minutes.
Background subtraction was performed using the temporal region for the parotid glands and the region superior to the thyroid gland for the submandibular glands.
Wilcoxon Signed Rank Test was used for statistical evaluation. (As another method was used in the abstract the p-values are differing from the abstract).
The USSR fell from 0,5 ml/min to 0,1 ml/min after treatment and did not increase thereafter. SSSR fell from 1,8 ml/min before to 0,2 ml/min three months after TBI/BMT and 0,7 ml/min after twelve months.
The changes were significant between all examinations – except for that no recovery of USSR was present after three months.
Regarding the parotid glands we found that scintigraphic differences were found before versus three months after treatment for Percentage stimulated secretion (S%), which decreased and Time to Maximum uptake (TMa), which was delayed.
The parotid emptying capacity (S%) decreased significantly from 79% before to 51% three months after treatment.
For the three patients completing the study no recovery (0%) of lost emptying capacity (S%) was obtained between three and twelve months after treatment.
Regarding the submandibular glands there were differences before versus three months after TBI/BMT for the shown variables Ma (maximal uptake) decreased and Mi (minimal uptake) increased, resulting in a reduced emptying capacity (S%). The final uptake level increased.
The emptying capacity in the submandibular glands decreased from 95% before TBI to 44% three months later.
For the three patients completing the study there was an almost total recovery (93%) of the emptying capacity at twelve months compared to the emptying capacity lost during the first three months of the study.
We conclude that the emptying capacity (or excretion capacity) was reduced three months after TBI/BMT in both parotid and submandibular glands. The capacity to recover lost emptying capacity seem to be present in submandibular glands, but not in parotid glands. The reduced recovering capacity of the parotid glands is a possible contributing factor to the reduced whole salivary secretion rate seen after TBI at BMT.
Longitudinal scintigraphic study of parotid and submandibular
Longitudinal scintigraphic study of parotid and submandibular gland function after total body irradiation at bone marrow transplantation Mats Bågesund 1,2 Sven Richter 3 Göran Dahllöf 2 1 Center for Orthodontics and Pedodontics, Linköping 2 Department of Pediatric Dentistry, Karolinska Institutet, Stockholm 3 Department of Nuclear Medicine, Huddinge University Hospital, Karolinska Institutet, Sweden