Engin K, Tupchong L, Waterman F M, Nerlinger R E, Leeper D B
Department of Radiation Oncology and Nuclear Medicine, Thomas Jefferson University, Philadelphia, PA 19107-5097.
Int J Hyperthermia. 1992 Nov-Dec;8(6):855-64. doi: 10.3109/02656739209005032.
In a prospective study CT scanning was used to evaluate the precision of thermometry catheter placement in tumours in the head and neck or on the chest wall in 30 consecutive patients prior to hyperthermia treatment. Patients had variable-sized tumours from several primary sites. Thermometry catheter placement was guided by palpation with or without a prior CT scan. Catheter placement was confirmed by CT. All lesions were less than 8 x 8 x 6 cm (L x W x D) in size. A mean of 4.2 +/- 0.2 (+/- 1 SEM, range 2-7) closed-end polyurethane catheters were inserted orthogonally by the same experienced radiation oncologist. Horizontal thermometry catheters were intended to traverse the centre and base of the tumour mass, and a vertical catheter was often inserted to intersect a horizontal catheter. After catheter placement, wire cables with 1 cm spacings were inserted into the catheters and positions determined using orthogonal films and CT scans. The success of catheter placement was judged on the following criteria: (1) catheter distribution factor (CDF = proportion of tumour CT slices transected by at least one catheter); (2) catheter hit ratio (CHR = average number of catheters in tumour per CT slice); (3) catheter miss factor (CMF = average number of catheters out of tumour per CT slice); (4) catheter placement index, CPI = [(CHR)(CDF)]-CMF; and (5) distance of nearest catheter from the visually estimated centre of tumour in the most central tumour CT scan. In the first seven lesions with 3-6 cm depth catheter insertion was guided by palpation only. In the next 23 lesions catheter insertion was guided by a prior CT scan. In the latter group, 15 lesions had depth 3-6 cm while eight lesions had depth < or = 3 cm. Catheter placement by palpation only, without the benefit of CT scan, was much less accurate in terms of the nearest catheter to the centre of the tumour (p = .001), the proportion of CT slices with catheter in tumour (CDF, p = 0.04) and the probability of a catheter being outside the tumour (CMF, p = 0.01). The catheter placement index (CPI) was a good measure of the accuracy and adequacy of catheter placement in large tumours (p = 0.04). Displacement of normal tissue structures by tumour precluded accurate catheter placement and led to a low CPI. It was difficult to accurately instrument lesions < or = 3 cm depth even with the benefit of a prior CT scan.(ABSTRACT TRUNCATED AT 400 WORDS)
在一项前瞻性研究中，对30例连续的患者在热疗前使用CT扫描评估头颈部或胸壁肿瘤中测温导管放置的精确性。患者的肿瘤大小各异，源于多个原发部位。测温导管放置通过触诊引导，部分患者有或没有事先的CT扫描。导管放置通过CT确认。所有病变大小均小于8×8×6厘米（长×宽×深）。由同一位经验丰富的放射肿瘤学家正交插入平均4.2±0.2（±1标准误，范围2 - 7）根封闭式聚氨酯导管。水平测温导管旨在穿过肿瘤块的中心和底部，且常插入一根垂直导管与水平导管相交。导管放置后，将间距为1厘米的电缆插入导管，并使用正交胶片和CT扫描确定位置。导管放置的成功依据以下标准判断：（1）导管分布因子（CDF = 至少被一根导管横切的肿瘤CT切片比例）；（2）导管命中比（CHR = 每CT切片肿瘤内导管的平均数）；（3）导管未命中因子（CMF = 每CT切片肿瘤外导管的平均数）；（4）导管放置指数，CPI = [(CHR)(CDF)] - CMF；以及（5）在最中心的肿瘤CT扫描中，最近导管距视觉估计的肿瘤中心的距离。在前7个深度为3 - 6厘米的病变中，导管插入仅通过触诊引导。在接下来的23个病变中，导管插入通过事先的CT扫描引导。在后一组中，15个病变深度为3 - 6厘米，而8个病变深度≤3厘米。仅通过触诊放置导管，而无CT扫描辅助，在距肿瘤中心最近的导管方面（p = 0.001）、肿瘤中有导管的CT切片比例（CDF，p = 0.04）以及导管位于肿瘤外的概率（CMF，p = 0.01）方面准确性要低得多。导管放置指数（CPI）是大肿瘤中导管放置准确性和充分性的良好指标（p = 0.04）。肿瘤对正常组织结构的移位妨碍了准确的导管放置，并导致低CPI。即使有事先的CT扫描辅助，对于深度≤3厘米的病变，也难以准确放置仪器。（摘要截断于400字）
