Efficacy and Safety of Percutaneous Ozone Injection Around Gasserian Ganglion for the Treatment of Trigeminal Neuralgia: A Multicenter Retrospective Study

Figures & data

Figure 1 Flow chart of inclusion of trigeminal neuralgia patients.

Figure 2 C-arm X-ray scans were performed to confirm the correct localization .

Notes: (A) C-arm image showing the trajectory of the needle after insertion. (B) C-arm scan showed that the tip of the trocar was located around foramen ovale. “a” was the point of the needle, “b” was the tail of the needle, and the arrow was the foramen ovale.

Table 1 Patient Demographics and Clinical Data

Characteristics	Baseline (Mean ± SD)
Gender(n)
Male	48
Female	55
Age, year
Mean ± SD	62.440 ± 11.060
Range	23–89
Pain Duration, Month
Median	18
Range	0.5–480
Pain Side(n)
Right	54
Left	47
Both	2
Branches Affected(n)
V1	11
V2	22
V3	14
V1+v2	16
V1+V3	3
V2+V3	31
V1+V2+V3	6
Preoperative VAS	7.19±1.38
Type of Prior Procedure(n)
MVD	11
PRF	14
GKRS	2
Destructive procedures	18

Abbreviations: VAS, visual analogue scale; MVD, microvascular decompression; PRF, pulsed radiofrequency; GKRS, gamma knife radiosurgery.

Table 2 Barrow Neurological Institute (BNI) Pain Intensity Scale

Score	Description
I	No pain, no medication
II	Occasional pain, not requiring medication
IIIa	No pain, completely controlled with medication
IIIb	Some pain, adequately controlled with medication
IV	Some pain, not adequately controlled with medication
V	Severe pain, no pain relief

Figure 3 Details of the BNI score.

Notes: (A) Bar chart showing the BNI score at follow-up in patients with total trigeminal neuralgia. (B) Bar chart showing the BNI score at follow-up in patients with classical trigeminal neuralgia. (C) Bar chart showing the BNI score at follow-up in patients with post-herpetic trigeminal neuralgia. 

Abbreviation: BNI, Barrow Neurological Institute.

Figure 4 Changes in VAS.

Notes: There was a significant decrease in pain intensity after the ozone injection in both groups (*P < 0.05), and this was even maintained for up to 24 months of the follow-up. No difference was found in the follow-up VAS scores between two groups (P > 0.05).

Abbreviation: VAS, visual analog scale.

Figure 5 Changes in von Frey.

Notes: Tactile detection: There was no difference in von Frey of group A and group B before the treatment (P > 0.05). After the ozone therapy, there was a significant decrease in von Frey (*P < 0.05) of group A and group B. Meanwhile, the von Frey of group A and group B have a significant difference after the ozone therapy (^#P<0.05).

Table 3 Univariate Analysis of Possible Outcome Predictors for Injection Effectiveness After 6 Months

Characteristics	Effective	Not Effective	P-value
Gender			0.985
Male	39	6
Female	46	7
Age(years)			0.162
<65	48	10
>65	37	3
Duration			0.580
≤6months	30	3
>6months	55	10
DM			0.001
Yes	13	7
No	72	6
Hypertension			0.577
Yes	23	2
No	62	11
PRF			0.263
Yes	10	3
No	75	10
MVD			0.752
Yes	7	2
No	78	11
Destructive procedures			0.038
Yes	10	5
No	75	8

Abbreviations: DM, diabetes mellitus; MVD, microvascular decompression; PRF, pulsed radiofrequency.

Table 4 Multiple Logistic Regression Analysis of Possible Outcome Predictors for Injection Effectiveness After 6 Months

Characteristics	OR	95% CI	P-value
DM	0.087	0.021–0.368	0.001
Destructive procedures	0.129	0.027–0.623	0.011
Constant	26.764		0.000

Abbreviations: DM, diabetes mellitus; OR, odds ratio; CI, confidence interval.

Table 5 Patient Characteristics at 2 Years Follow-Up

Pt. No.	TN Classification	Age	Gender	Side	Pre-Operative BNI	2 Years Followed-Up BNI	Pre-Operative VAS	2 Years Followed-Up VAS	DM History	Destructive Procedures History	Pre-Von Frey	Post-Von Frey
1	Primary	68	F	Right	5	1	8	0	N	N	0.008	0.008
2	Primary	68	M	Right	5	1	7	1	N	N	0.008	0.008
3	Primary	46	M	Left	4	2	9	2	N	Y	0.008	0.008
4	Primary	68	M	Right	4	1	10	1	Y	N	0.6	0.008
5	Primary	65	M	Bilateral	5	1	8	0	N	N	0.008	0.008
6	Secondary	64	F	Left	4	4	7	7	Y	Y	0.008	0.008
7	Secondary	48	F	Left	4	2	7	1	N	N	0.008	0.008
8	Secondary	59	M	Left	5	1	8	1	N	N	0.07	0.008
9	Secondary	70	F	Left	4	2	8	2	N	Y	0.008	0.008
10	Primary	62	M	Left	4	2	8	2	N	N	0.008	0.008
11	Primary	69	F	Right	4	4	8	8	Y	Y	0.07	0.008
12	Primary	66	F	Left	4	1	8	1	N	N	0.008	0.008
13	Primary	81	F	Left	5	3	9	4	N	N	0.008	0.008
14	Primary	63	M	Left	5	3	6	4	N	Y	0.008	0.008
15	Primary	73	M	Right	5	2	8	2	Y	Y	0.6	0.6
16	Primary	60	F	Right	4	2	8	3	N	N	0.008	0.008
17	Primary	75	F	Right	4	1	8	1	N	N	0.008	0.008
18	Secondary	51	M	Left	4	1	5	2	N	N	0.008	0.008
19	Secondary	74	F	Right	5	1	8	2	N	N	0.008	0.008
20	Primary	80	M	Right	4	2	6	2	N	Y	0.02	0.008
21	Primary	23	F	Left	4	2	7	6	N	N	0.008	0.008
22	Primary	60	F	Left	5	4	8	2	N	N	0.008	0.008
23	Primary	74	F	Left	5	2	8	2	N	N	0.2	0.2
24	Secondary	67	F	Right	5	2	8	2	N	N	0.008	0.008
25	Secondary	64	F	Left	5	1	9	2	N	N	0.4	0.008
26	Secondary	81	F	Right	4	2	9	2	N	N	1	0.008
27	Primary	38	M	Right	4	2	7	3	N	N	0.008	0.008

Abbreviations: TN, trigeminal neuralgia; F, female; M, male; BNI, Barrow Neurological Institute; VAS, visual analogue scale; DM, diabetes mellitus; Y, yes; N, no.

Table 6 Multiple Logistic Regression Analysis of Possible Outcome Predictors for Injection Effectiveness After 2 Years

Characteristics	OR	95% CI	P-value
DM	0.079	0.002–2.680	0.158
Destructive procedures	0.019	0.000–0.935	0.046
Gender	0.085	0.002–3.297	0.186
Age	1.050	0.936–1.179	0.406
Constant	17.000		0.404

Abbreviations: DM, diabetes mellitus; OR, odds ratio; CI, confidence interval.