Sei Fukui

Patterns of pain induced by distending the thoracic zygapophyseal joints.

Background and Objectives. The study was designed to investigate the patterns of referral pain associated with the thoracic zygapophyseal joints (C7‐T1 to T2‐3, T11‐12). Methods. In 15 patients who had back pain suspected to be of zygapophyseal origin and for whom pain was relieved by injection of local anesthetic into the joints under fluoroscopic guidance, the zygapophyseal joints from C7‐T1 to T2‐3, T11‐12 were distended by injecting contrast medium. If injection reproduced typical pain in the patient, the patient was asked to describe the distribution of pain, which was recorded on a body diagram. Results. A total of 21 joints were studied. Composite pain distribution maps for the thoracic zygapophyseal joints from C7‐T1 to T2‐3 and for the T11‐12 joint were drawn. The distribution of referred pain was as follows: pain in the suprascapular region was referred from C7‐T1 and Th1‐2; pain in the superior angle of the scapula from C7‐T1 and T1‐2; pain in the midscapular region from C7‐T1, T1‐2, and Th2‐3; and pain in the paravertebral region around the site of injection and the area over the iliac crest from T11‐12. Conclusions. The referred pain distribution for joints C7‐T1 to Th2‐3 showed significant overlap.

Changes in regional cerebral blood flow in the thalamus after electroconvulsive therapy for patients with complex regional pain syndrome type 1 (preliminary case series)

Background and Objectives The aim of the present case series was to examine whether changes in regional cerebral blood flow (rCBF) induced by electroconvulsive therapy (ECT) in the thalamus are related to the efficacy of ECT. Four chronic pain patients with complex regional pain syndrome (CRPS) type-1 (age, 33 to 58 years) who had failed to respond to standard pain treatments received a course of ECT. To investigate the possible mechanisms of the analgesic effect of ECT on chronic CRPS type-1, we measured significant changes in the rCBF of the thalamus using technetium-99m ethyl cysteinate dimer single photon emission computed tomography (99mTc ECD SPECT), before and after ECT and compared these values between responders and nonresponders. Results Two of 4 (50.0%) patients responded to ECT treatment (response defined as a reduction of at least 60% on the visual analog scale [VAS]). 99mTc ECD SPECT showed that the mean contralateral thalamus-to-cerebellum ratio increased 11.5% after ECT compared with the ratio before ECT in the 2 responders, but remained unchanged in nonresponders. Conclusions The results from the SPECT suggest that normalization of the balance of rCBF in the thalamus may be related to the analgesic efficacy of the ECT on CRPS Type-1.

Pain patterns originating from the sacroiliac joints

region, the posterior thigh region, and the groin region (Fig. 1). Each patient was asked which region or regions their pain occurred in before they received a SI joint injection. A diagnosis of SI joint pain was made if all of the following clinical features were present: (1) pain perceived in the region of the SI joint with or without referred pain; (2) the injection of a local anesthetic into the capsule of a SI joint relieved the pain by more than 80% compared with the level of pain before the injection; (3) the pain could be reproduced by physical examination techniques which stress the joint (Gaenslen’s test or Patrick’s test) [1,2]. Patients with these criteria were selected for this study. The SI joint injection was performed with the patient lying on a fluoroscopy table in a prone position. A posterior approach allowed visualization of the joints using the technique described by Fortin et al. [4]. Under intermittent fluoroscopic control, and after identifying the inferior extent of the joint, a 22-gauge needle was inserted through the skin from 1–3cm below the inferior margin of the SI joint, and directed cephalad to strike the ilium 1cm above the inferior margin of the joint. The accuracy of the placement was confirmed by arthrography. Once the needle had penetrated the joint capsule, a small amount of contrast medium (Iohexol: omnipaque) was injected until the initial instillation of the contrast medium outlined the joint. The volume of contrast injected averaged 2.4ml per subject (range 2.46 0.66ml). After the injection of contrast medium, a mixture of 2 ml local anesthetic (1% mepivacaine) and 2mg dexamethazone was injected into the joint space as a therapeutic procedure. Patients whose pain was reproduced by intraarticular injection were selected for this study, while those whose pain pattern did not coincide with their original pain were excluded. For the 28 patients enrolled in this study, SI joint injection was performed into a total of 32 joints. Four

Successful relief of hip joint pain by percutaneous radiofrequency nerve thermocoagulation in a patient with contraindications for hip arthroplasty.

and groin for years. She experienced gradually worsening pain in the inguinal, thigh, and hip area to the level that she could not walk, sit, take care of herself at home, and sleep well. She was only able to ambulate with a wheelchair. The pain was constant, severe, sharp, and deep in her thigh, groin, and hip. It radiated to the left anterior knee at times. Past conservative drug therapy had failed. Hip arthroplasty was contraindicated because of the presence of severe lymphedema and the high risk of infection. The hip x-ray indicated severe bilateral hip joint destruction. MRI of pelvis also indicated severe bilateral hip joint degeneration and destruction.

Chronic pain with beneficial response to electroconvulsive therapy and regional cerebral blood flow changes assessed by single photon emission computed tomography

Background Recent neuroimaging studies suggested that chronic neuropathic pain may be largely sustained by a complex neuronal network involving the thalamus. Although recent studies have demonstrated the efficacy of electroconvulsive therapy (ECT) in the treatment of a variety of types of chronic neuropathic pain, the effects of ECT on regional cerebral blood flow (rCBF) have not been studied. Objectives and Methods We present a 50-year-old female postsurgical chronic pain patient whose pain had failed to respond to standard pain treatment, but was resolved by ECT. To investigate the potential role of rCBF in ECT’s analgesic effect, we measured significant changes in the rCBF in the thalamus before and after a course of bilateral ECT using technetium-99m ethyl cysteinate dimer (99mTc-ECD) single photon emission computed tomography (SPECT). Results 99mTc-ECD SPECT showed a significant bilateral decrease in the thalamus on the side of the pain, and this decreased rCBF in the thalamus increased after ECT. Conclusions The results from the SPECT suggest that ECT increases abnormally decreased thalamus activity in chronic neuropathic pain.

Results of Intradiscal Pulsed Radiofrequency for Lumbar Discogenic Pain: Comparison with Intradiscal Electrothermal Therapy

Background We have developed an intradiscal pulsed radiofrequency (Disc PRF) technique, using Diskit II® needles (NeuroTherm, Wilmington, MA, USA), as a minimally invasive treatment option for chronic discogenic low back pain (LBP). The purpose of this study was to compare the representative outcomes of Disc PRF and Intradiscal Electrothermal Therapy (IDET) in terms of pain relief and reduction of disability. Methods Thirty-one patients with chronic discogenic LBP who underwent either Disc PRF (n = 15) or IDET (n = 16) were enrolled in the study. A Diskit II® needle (15-cm length, 20-gauge needle with a 20-mm active tip) was placed centrally in the disc. PRF was applied for 15 min at a setting of 5 × 50 ms/s and 60 V. The pain intensity score on a 0-10 numeric rating scale (NRS) and the Roland-Morris Disability Questionnaire (RMDQ) were assessed pretreatment and at 1, 3, and 6 months post-treatment. Results The mean NRS was significantly improved from 7.2 ± 0.6 pretreatment to 2.5 ± 0.9 in the Disc PRF group, and from 7.5 ± 1.0 to 1.7 ± 1.5 in the IDET group, at the 6-month follow-up. The mean RMDQ also showed significant improvement in both the Disc PRF group and the IDET group at the 6-month follow-up. There were no significant differences in the pretreatment NRS and RMDQ scores between the groups. Conclusions Disc PRF appears to be an alternative to IDET as a safe, minimally invasive treatment option for patients with chronic discogenic LBP.

Evaluation of thalamic neural activity in CRPS type 1 patients by proton MR spectroscopy: a correlative study with rCBF

(one in the right hand, one in the right leg, and two in the left leg). The duration of the pain was 1, 3, 3, and 6 years, respectively. The severity of pain was rated as 4 to 8 on a visual analogue scale (VAS) (0, no pain; 10, maximal pain). The pain was resistant to standard treatment, including nerve block and various medications (anticonvulsants, intravenous lidocaine, oral mexiletine, intravenous ketamine, and antidepressants). To measure the neural activity of the thalamus, we performed 1H-MRS with a 1.5-T SIGNA MR system (General Electric, Milwaukee, WI, USA) employing the standard circular polarized head coil. The 2 2 2cm volume of interest was selected in the bilateral thalamus region by axial T1-weighted MR imaging (Fig. 1). 1H-MRS spectra were obtained by a simulated-echo method with chemical shift selective saturation pulse sequence with a repetition time of 6s, an echo time of 300ms, and 600 acquisitions. Positioning of each voxel was performed by an experienced neuroanatomist and adjusted to the thalamus of the individual brains. The spectra were analyzed with OMEGA software (GE Medical Systems, Milwaukee, WI, USA) at a SPARC workstation (SUN Microsystems, Milwaukee, WI, USA). The MR spectra constantly showed two major peaks corresponding to NAA and Cr (Fig. 2). We measured the NAA/Cr ratio (%), which reflects neural activity, in the four patients. Measurement of rCBF by xenon-CT was conducted using the conventional protocol (a wash-in, 5min washout method with 3min inhalation of 30% xenon gas) at a transverse slice 5cm above the orbitomeatal line (OM line) from a single CT slice at the level of the basal ganglia, including the thalamus [8–10]. The calculations of rCBF were semiautomatic and were performed with xenon-CT software. The patients were informed about the measurement protocol, which was approved by the hospital ethical committee. Informed consent was obtained from all patients before measurement.

Central pain associated with low thalamic blood flow treated by electroconvulsive therapy

table central poststroke pain throughout his right hemibody, mostly in the upper and lower extremities, had lasted for almost 3 years. Three years after the event, he was referred to the pain clinic of the Department of Anesthesiology, Shiga University of Medical Science, in order to receive a course of ECT treatment for his persistent pain. Visual analogue scale (VAS) levels for pain were rated as 8–10 (0, no pain; 10, maximal pain). He was unable to resume walking because of the persistent pain. The patient was informed about the treatment protocol, which was approved by the Hospital Ethical Committee, and about the possible benefits and side-effects of ECT. Informed oral and written consent was obtained before ECT. Medication at that time consisted of 30mg·day 1 nortriptyline and 300mg·day 1 carbamazepin. The ECT was conducted by brief-pulse stimulus (frequency 60Hz, pulse width 1 ms, current 0.7 A, stimulus duration 2.8 s) once a week over 8 weeks unilaterally using a Thymatron DGX (Somatics) and seizure was assured by EEG monitoring and by viewing cuffed-limb seizures. The unilateral ECT application was to the nondominant hemisphere and ipsilateral to the cerebral vascular accident. Hypnosis was induced with a bolus injection of thiopental (2–3 mg·kg 1), and muscle relaxation was achieved by succinylcholine (1–1.5 mg·kg 1 IV). Ventilation was assisted using a facemask with 100% oxygen, and nicardipine (0.5–1.5mg IV) was injected to attenuate acute cardiovascular side-effects. A course of eight unilateral ECT treatments resulted in a reduction in pain. After ECT treatment, the patient still had some occasional pain, but was able to tolerate it. VAS levels for pain after ECT were rated 2–5. His mental state and daily activities improved, and he could enjoy walking. He suffered retrograde and anterograde memory impairments transiently, but recovered within 2 months. One and half years after the ECT treatment, the reduction in central poststroke pain has persisted.

Phantom pain with beneficial response to electroconvulsive therapy (ECT) and regional cerebral blood flow (rCBF) studied with Xenon-CT

AbstractWe present a phantom limb pain patient whose ongoing pain was resolved after electroconvulsive therapy (ECT). Before ECT, regional cerebral blood flow (rCBF) on the ipsilateral side of the anterior cingulate cortex (BA32) and insula increased, compared to the pain on the patients contralateral side. These asymmetries in the anterior cingulate cortex and insula were normalized after ECT, when the phantom limb pain subsided. There were no abnormalities or significant right-left differences of rCBF in the thalamus. Our results suggest that the rCBF of the anterior cingulate cortex and insula were related to the analgesic efficacy of the ECT.

Changes on MRI in lumbar disc protrusions in two patients after intradiscal electrothermal therapy.

We examined changes to the protruded lumbar disc after intradiscal electrothermal therapy (IDET) using magnetic resonance imaging (MRI) in two patients with chronic discogenic low back pain who underwent IDET. MRI was performed before and 6 months after the treatments. In the follow-up MRI studies, the protrusions were almost abolished and normalized in both patients. We thus confirmed shrinkage of the protruded disc by IDET on MRI images in two patients.