Method for eradicating pain of central origin resulting from spinal cord injury

• US 20040006376A1
• Filed: 08/30/2002
• Published: 01/08/2004
• Est. Priority Date: 06/27/2002
• Status: Active Grant

• Current Assignee: Scott P. Falci
• Original Assignee: Scott P. Falci
• Inventors: Falci, Scott P.
• Granted Patent: US 7,130,691 B2
• Time in Patent Office: Days
• US Class Current: 607/46
• CPC Class Codes: A61B 5/24 Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
• CPC Class Codes: A61B 5/407 Evaluating the spinal cord A61B5/4896 takes precedence
• CPC Class Codes: A61B 5/4824 Touch or pain perception evaluation A61B5/4821 takes precedence

Abstract

Methods are provided to reliably identify and surgically eradicate aberrant DREZ in patients suffering from spinal cord injury. The methods include identifying potential aberrant DREZ using a combination of mapping techniques based on the location of the patients perceived pain, analysis of the spontaneous electrical hyperactivity in targeted DREZ, and analysis of evoked transcutaneous C-fiber stimulation both in pre-operative and operative conditions. Methods are also provided for identifying potential pain effecters in aberrant DREZ, useful in the preparation of non-invasive therapeutics for central pain characteristic of spinal cord injury.

Claims

1. A method for minimizing central pain in a patient having a spinal cord injury, the method comprising:

determining the level of injury in the patient;

determining the location of perceived central pain in the patient;

mapping the location of the perceived pain in the patient to a potential pain generating DREZ of the patient'"'"'s spinal cord, the mapping consistent with a pre-determined somatotopic map, wherein the somatotopic map provides a standard guide for a DREZ location that correlates to a perceived central pain, as previously determined from a series of test subjects having spinal cord injuries; and

surgically exposing and causing one or more lesions in the identified pain generating DREZ, wherein the one or more lesions minimizes central pain in the patient.

2. The method of claim 1 further comprising:

pre-surgically performing a first transcutaneous C-fiber stimulation on the patient to confirm potential pain generating DREZ between the level of injury in the spinal cord and DREZ located cephalad to the level of injury in the spinal cord, wherein a positive transcutaneous C-fiber result confirms whether a DREZ identified by somatotopic mapping is a pain generating DREZ.

3. The method claim 2 further comprising:

performing a second transcutaneous C-fiber stimulation on the previously identified pain generating DREZ to both confirm and identify potential pain generating DREZ in the patient, wherein the transcutaneous C-fiber stimulation is performed on surgically exposed DREZ.

4. The method of claim 3 wherein the second transcutaneous C-fiber stimulation is performed on DREZ located cephalad, at, and caudal to the level of injury in the patient with the spinal cord injury, wherein the second transcutaneous C-fiber stimulation confirms the somatitopically mapped pain generating DREZ and first transcutaneous C-fiber stimulation identified DREZ cephalad to the level of injury, and further confirms and identifies pain generating DREZ caudal to the level of injury that were previously identified by somatotopic mapping.

5. The method of claim 3 further comprising:

confirming, before or after the second transcutaneous C-fiber stimulation, whether the previously identified, through somatotopically mapping and the first transcutaneous C-fiber stimulation, pain generating DREZ are neuroelectrically active by performing a spontaneous electrophysiologic analysis on the surgically exposed DREZ, wherein aberrant neuroelectric activity in a surgically exposed DREZ indicates that the DREZ is a pain generating DREZ.

6. The method of claim 5 further comprising:

testing the neuroelectric activity on the pain generating DREZ through spontaneous electrophysiologic analysis after the one or more lesions have been surgically introduced into the pain generating DREZ, wherein aberrant neuroelectric activity indicates that additional lesions are required in the pain generating DREZ.

7. The method of claim 1 wherein each lesion in the pain generating DREZ site(s) is introduced by radio-frequency microcoagulation at about 90°

C. for 30 seconds.

8. The method of claim 7 wherein any two lesions in the target DREZ sites are separated by about one millimeter.

9. The method of claim 3 wherein pain generating DREZ have C-fiber perception at or above 0.35 mA.

10. The method of claim 1 wherein the somatotopic map provides that perceived pain in the patient'"'"'s trunk maps to potential pain generating DREZ located between T1 and T6 in the patient'"'"'s spinal cord.

11. A method for identifying an effecter of central pain in a patient with a spinal cord injury, the method comprising:

identifying pain generating DREZs in the patient;

identifying normal DREZs in the patient;

taking a sample from the pain generating DREZ and taking a sample from the normal DREZ in the patient; and

identifying a pain effecter in the pain generating DREZ by comparing effecters in the pain generating DREZ to effecters in the normal DREZ;

wherein the comparing step utilizes biochemical and/or molecular techniques to search for differences in effecters between the pain generating DREZ and the normal DREZ.

12. The method of claim 11 wherein the identifying pain generating DREZs includes evoking neuroelectric hyperactivity in the patients DREZs to identify pain generating DREZs.

13. The method of claim 11 wherein the sample is a 1 mm by 1 mm by 2 mm biopsy.

14. The method of claim 11 wherein the comparing step further includes a determination of excitatory amino acid receptor levels in pain generating DREZs and normal DREZs.

15. The method of claim 14 wherein the excitatory amino acid receptor is N-methyl-D-aspartic acid receptor.

16. The method of claim 11 wherein the comparing step further includes a determination of the levels of sodium channels in pain generating DREZs and normal DREZs.

17. A method for preparing a somatotopic map used in identifying aberrant DREZ in a patient with a spinal cord injury, the method comprising:

comparing the perceived pain in a patient having a spinal cord injury to neuroelectrically active DREZ in the patient; and

reducing the neuroelectric activity in the identified DREZ to non-aberrant neuroelectric activity and determining whether the patient continues to have the perceived pain;

wherein, the location of the perceived pain is mapped to the identified DREZ if the reduction in neuroelectric activity correlates to the reduction in perceived pain by the patient, and wherein a map is prepared that correlates the perceived pain of the patient to the location of the identified DREZ.

18. The method of claim 17 wherein the somatotopic map is prepared from two or more patients having spinal cord injuries.

19. The method of claim 17 wherein a patient has perceived pain in the trunk and the map indicates that the potentially aberrant DREZ are from T1 to T6.

20. The method of claim 17 wherein a patient has a perceived pain in the legs or feet and the map indicates that the potentially aberrant DREZ are from T 11 to L1.