Characteristic Uptake Pattern of Bone Scintigraphy in Patients with Hepatocellular Carcinoma Following Treatment with High-Intensity Focused Ultrasound

Abstract

Purpose This study retrospectively reviews the characteristic bone scintigraphic findings in 18 patients with hepatocellular carcinoma (HCC) following treatment with high-intensity focused ultrasound (HIFU). A potential complication of HIFU is damage to the tissues along the path of the ultrasound beam and structures superficial to the lesion of interest. Methods Patients with hepatocellular carcinoma who underwent a bone scan between 1st December 2005 and 31st December 2011 were considered for this study. Among these patients, only those who had bone scans after the HIFU treatment were included. The time between HIFU treatment and bone scans, HIFU energy, HCC sites, tumour sizes and related radiological findings were evaluated. Results In total, 20 bone scans of 18 patients were reviewed. Of these scans, two patients were normal; three patients showed decreased uptake, four patients showed increased uptake and nine patients showed mixed uptakes of the bony tracer in their rib cages. The defects were located in the anterior, lateral, anterolateral or posterolateral aspects of the rib cage. The majority of those cold defects were in the right anterior rib cages. SPECT/CT was used to localise the decreased uptake in ribs. The magnetic resonance imaging in individual patients invariably showed ill-defined rim enhancement along the right chest wall, signifying chest wall injury. Conclusions The results showed that tissue ablation using HIFU caused tissue injury along the pathway of highintensity ultrasound beams. The harm to tissues is presented as photopenic area on the rib cages due to necrosis or hot spots due to rib fractures in the bone scan. Since these cold defects are subtle, they are easily overlooked or mistaken as aggressive bony metastasis.

Diagnostics différentiels d’images d’hypofixations sur une scintigraphie du squelette: à propos d’un cas de leucémie aigue lymphoblastique

“…Dans tous les cas, ces atteintes osseuses ne modifient heureusement pas le pronostic des leucémies aigues chez l'enfant [ 14 ]. Il est enfin utile de rappeler que des hypofixations sur une scintigraphie du squelette peuvent être en rapport avec certaines tumeurs bénignes (hémangiome [ 15 ]), des métastases (thyroïde, rein, neuroblastome [ 5 , 16 , 17 ]), certains traitements anticancéreux notamment la radiothérapie et le traitement par les ultrasons (hypofixations costales chez des patients atteints hépatocarcinomes [ 18 ]), une infection osseuse [ 5 ], ou bien rester dans de rares cas sans cause décelable [ 19 ].…”

Osseous vitality in single photon emission computed tomography/computed tomography (SPECT/CT) after balloon tibioplasty of the tibial plateau: a case series

“…Combining functional SPECT images with high-resolution morphologic CT scans, osteonecrosis can be well evaluated, which has been shown in a SPECT/CT study about femoral head osteonecrosis by Motomura et al [ 22 ]. Another study by Ma et al [ 38 ] showed that tissue ablation using high-intensity focused ultrasound ultimately led to osteonecrosis, which could be visualized by photopenic areas surrounded by an increased tracer region on planar scintigraphic images [ 20 , 39 ]. The mechanism was based on a rapid temperature increase, which is comparable to cement hardening.…”

“…The present study is consistent with this report, showing increased SPECT/CT activity in a lengthy period of time, although the general impression was a decrease in the mean uptake ratio with time. This increased activity can most likely be attributed to bone remodeling after surgical fracture treatment [ 38 ].…”