A novel five-category multimodal T1-weighted and T2-weighted magnetic resonance imaging-based stratification system for the selection of spinal arachnoid cyst treatment: a 15-year experience of 81 cases

Figures & data

Figure 1 (A and B) Classification of spinal arachnoid cysts. (A) Two anatomical types of spinal arachnoid cysts; (B) novel five-type classification system determined by magnetic resonance imaging (MRI).

Table 1 Incidence, resection modality, and prognosis of the five types of spinal arachnoid cysts

	Patients, n	Sex (male), n	Mean age	Resection modality		Prognosis (FM scale)*
				Subtotal resection, n (%)	Total resection, n	Significant improvement, n	Improvement, n	No improvement, n
Intramedullary cysts/syrinxes	8 (100%)	3 (37.5%)	33.0	6 (75%)	2 (25%)	8 (100%)	0 (0%)	0 (0%)
CI–T2	5 (62.5%)	2 (40%)	32.4	4 (80%)	1 (20%)	5 (100%)	0 (0%)	0 (0%)
T3–LI	3 (37.5%)	1 (33.3%)	34.0	2 (66.7%)	1 (33.3%)	3 (100%)	0 (0%)	0 (0%)
L2–SI	0	0	0	0	0	0	0	0
Subdural extramedullary	15 (100%)	6 (40.0%)	30.3	10 (66.7%)	5 (33.3%)	13 (86.7%)	2 (13.3%)	0 (0%)
CI–T2	1 (6.7%)	0 (0%)	29.0	1 (100%)	0 (0%)	1 (100%)	0 (0%)	0 (0%)
T3–LI	14 (93.3%)	6 (42.9%)	30.4	9 (64.3%)	5 (35.7%)	12 (85.7%)	2 (14.3%)	0 (0%)
L2–SI	0	0	0	0	0	0	0	0
Subdural/epidural	1 (100%)	1 (100%)	38.0	0 (0%)	1 (100%)	1 (100%)	0 (0%)	0 (0%)
CI–T2	0	0	0	0	0	0	0	0
T3–LI	1 (100%)	1 (100%)	38.0	0 (0%)	1 (100%)	1 (100%)	0 (0%)	0 (0%)
L2–SI	0	0	0	0	0	0	0	0
Intraspinal epidural	54 (100%)	23 (42.6%)	31.2	19 (35.3%)	35 (64.8%)	36 (66.7%)	13 (24.1%)	5 (9.26%)
CI–T2	0	0	0	0	0	0	0	0
T3–LI	9 (16.7%)	4 (44.4%)	31.1	0 (0%)	9 (100%)	5 (55.6%)	4 (44.4%)	0 (0%)
L2–SI	45 (83.3%)	19 (42.2%)	31.2	19 (42.2%)	26 (57.8%)	31 (68.9%)	9 (20%)	5 (11.1%)
Intraspinal/extraspinal	3 (100%)	1 (33.3%)	39.6	0 (0%)	3 (100%)	3 (100%)	0 (0%)	0 (0%)
CI–T2	0	0	0	0	0	0	0	0
T3–LI	2 (66.7%)	1 (50%)	40.5	0 (0%)	2 (100%)	2 (100%)	0 (0%)	0 (0%)
L2–SI	1 (33.3%)	0 (0%)	38.0	0 (0%)	1 (100%)	1 (100%)	0 (0%)	0 (0%)

Notes:

* Fugl-Meyer (FM) scores were evaluated at postoperative day 90. FM scores in preoperation patients were less than 50 points. Significant improvement slight motor impairment (96–99 points). Improvement: moderate motor impairment (85–95 points). No improvement: severe or marked motor impairment (0–84 points).