神経膠腫の治療経過に伴う201T1—SPECTの変化—治療効果判定に関する有用性について

Sequential Change of SPECT Using 201T1 Chloride During the Treatment of Intracranial Gliomas

　本稿は，神経膠腫の治療経過に伴うT1—SPECTの変化を分析し，本法による治療効果判定に関する有用性を検討した。26シリーズの神経膠腫を対象とした。T1—SPECTは治療（放射線治療および化学療法）前後に施行した。撮像は，201T1 chloride静注後10分（early image）と4時間（delayed image）に行い，腫瘍性病変と健側脳白質のcount数比（L／N比）を両imageで測定した。治療反応群と治療抵抗群の治療前後のL／N比の変化を分析した。治療反応群は治療後delayed L／N比が有意に低下し（p＜0.05），治療抵抗群は治療後delayed L／N比が有意に上昇した（p＜0.05）。以上より，T1—SPECTは神経膠腫の治療に伴い変化し，治療後L／Nの低下は治療が有効であることを，治療後L／Nの上昇は治療が有効に行われていないことを反映すると考えられた。

The authors followed up the change in SPECT using ²⁰¹T1 chloride (T1-SPECT) according to the course of treatment of intracranial gliomas and analyzed the difference in T1-SPECT between the stable and progressive groups. The subjects were 26 series of supratentorial giomas subjected to T1-SPECT before and after the treatment (radio-the-rapy and chemotherapy). They were put on T1-SPECT after 10 minutes (early image) and 4 hours (delayed) following 74 MBq of ²⁰¹T1 chloride intra-venous injection.

Besides, RI count ratio (L/N) in the tumor lesion(L) and contralateral parenhyma (N) was mea-sured. The patients were divided into stable and progressive groups judging from the therapeutic effects, the change in L/N ratio between before and after the treatment was analyzed. The stable group showed a significant post-treatment decrease in L/N ratio compared with a significant post-treatment increase therein for the progressive group. This result suggested T1-SPECT to change according to the course of treatment and to be applicable to the judgement of the therapeutic effect on gliomas.