RESUMO
UNLABELLED: This study investigated the radiographic and scintigraphic courses of union in cervical interbody fusion using hydroxyapatite (HA) grafts or iliac bone autografts. METHODS: Twelve patients underwent both serial plain radiography and bone scintigraphy during the 12 mo after surgery. Serial plain radiographs were obtained every month until the end of the study period. Bone scintigrams with 99mTc-hydroxymethylene diphosphonate (HMDP) were obtained at 2 wk and at 1, 2, 3, and 6 mo. Uptake of 99mTc-HMDP in the graft was expressed as a ratio of the counts in the graft to those in the axis. RESULTS: In the HA graft group, the plain radiographs of all patients showed a radiolucent stripe that disappeared 7.3 +/- 1.5 (mean +/- SD) months after surgery. In the autograft group, a radiolucent stripe around the graft was not seen for any patient, and union was confirmed by follow-up radiographs within 6 mo after surgery. The serial changes in the 99mTc-HMDP uptake ratio showed no difference between the 2 groups. The 99mTc-HMDP uptake ratio peaked 1 mo after surgery and decreased rapidly to a plateau within 2 mo. CONCLUSION: In the HA graft group, despite the presence of a radiolucent stripe around the graft for more than 6 mo, the scintigraphic course of union was not different from that in the autograft group. The likelihood is that the presence of a radiolucent stripe around the HA graft in the early months after surgery is not always a sign of pseudoarthrosis.
Assuntos
Materiais Biocompatíveis , Vértebras Cervicais/cirurgia , Durapatita , Ílio/transplante , Fusão Vertebral , Medronato de Tecnécio Tc 99m/análogos & derivados , Vértebras Cervicais/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pseudoartrose/diagnóstico por imagem , Radiografia , Cintilografia , Compostos Radiofarmacêuticos , Fatores de TempoRESUMO
We performed blinded visual evaluation of MR angiography (MRA) films in 44 patients with unilateral carotid artery stenosis to determine whether a flow gap and poststenotic signal attenuation on 3D-PC MRA were useful signs of severe carotid artery stenosis. Although nine patients with a flow gap alone had various degrees of stenosis ranging from 22.2 to 77.3% without any decrease in regional cerebral blood flow (rCBF), 13 patients with both a flow gap and poststenotic signal attenuation had severe stenoses of 80% or more, with a definite decrease in baseline rCBF. The presence of both a flow gap and poststenotic signal attenuation on 3D-PC MRA appeared to be a reliable marker of severe carotid artery stenosis with a decrease in rCBF.