Selective Percutaneous Controlled Radiofrequency Thermocoagulation of the Gasserian Ganglion To Control Facial Pain Due to Medication-Related Osteonecrosis of the Jaw.

BACKGROUND: Medication-related osteonecrosis of the jaw (MRONJ) is an important complication in patients treated with antiresorptive agents such as bisphosphonates and the receptor activator of nuclear factor κB ligand inhibitor (denosumab). Treatment of MRONJ is extremely difficult, which makes it a distressing long-term complication. OBJECTIVES: We report a case of intractable facial pain due to MRONJ that was successfully controlled with selective percutaneous controlled radiofrequency thermocoagulation of the Gasserian ganglion. SETTING: A 68-year-old woman with breast cancer was diagnosed as having MRONJ. She was very distressed because of jaw pain and infections secondary to MRONJ. Her quality of life (QOL) was severely decreased. Since alleviation of the MRONJ could not be expected within the patient's life expectancy, it was decided to investigate the usefulness of selective percutaneous controlled radiofrequency thermocoagulation of the Gasserian ganglion to control the pain. RESULTS: After the procedure, the anesthesia was obtained in the distribution of the third branch of the trigeminal nerve, and the pain completely disappeared. Although hypoesthesia was provoked as a complication, it was tolerated by the patient and she was very satisfied. Up to the time of death, there was no recurrence of pain or worsening of the MRONJ. DISCUSSION: This procedure is a common technique for treating trigeminal neuralgia. Its effect is immediate and long lasting, although it provokes hypoesthesia in treated division, and it is also suited for cancer patients in terminal stage. This case suggests that the procedure was useful for improving the patient's QOL.

[Medroxyprogesterone Acetate as Part of Palliative Care for Terminal-Stage Breast Cancer Patients--A Report of Two Cases].

Various effective strategies have recently been described in the treatment of breast cancer, including endocrine therapy, chemotherapy, and molecular-targeted therapy, providing long-term survival benefits even after cancer recurrence. However, terminal-stage patients experience side effects and worse quality of life (QOL), in addition to deterioration of their general condition caused by the progression of the disease itself. When providing the best supportive care, use of anti-cancer drugs is not taboo and can represent a good option as long as physical, social, psychological, and spiritual supports are provided to both the patients and their families. Medroxyprogesterone acetate (MPA) is an endocrine therapeutic drug. In Japan, MPA is used only as a late-line endocrine therapy for breast cancer recurrence because many other endocrine therapy drugs are much more effective and MPA increases the risk of thrombosis and obesity. Here, we report 2 patients with breast cancer who reached terminal stage more than 10 years after the first diagnosis. MPA was administered as the final-line treatment. During that time, their appetite and QOL improved and the patients became more active than when they had been undergoing aggressive anticancer treatment. Both patients spent quality time with their families until their death. MPA may be a good option as part of palliative care of breast cancer patients in terminal stage.

Risk factors related to accidental intravascular injection during caudal anesthesia.

Recently, ultrasound-guided caudal anesthesia has been performed for postoperative pain management after lumbar spine surgery. Although it is well known that intravascular injection often occurs in the caudal part of the spine, and that this cannot be detected at the time of injection under ultrasound screening, the risk factors for intravascular injection have not been evaluated. To assess the risk index for prediction of accidental intravascular injection during caudal anesthesia, we retrospectively examined the hospital records of patients suffering from chronic low back pain who underwent sacral epidurography. Multivariate logistic regression analysis demonstrated that radicular symptoms of the lumbar spine (OR, 2.511, 95% CI, 1.097-5.748) and duration of symptoms (OR, 1.006, 95% CI, 1.002-1.010) were significant and independent risk factors for accidental intravascular injection during sacral epidurography. This study suggests that the incidence of accidental intravascular drug injection during caudal anesthesia would be higher in patients with chronic radicular symptoms of the lumbar spine.

Predictive factors for postherpetic neuralgia using ordered logistic regression analysis.

OBJECTIVES: To identify predictive factors for the occurrence of postherpetic neuralgia (PHN). METHODS: The participants were 73 herpes zoster patients who had been treated at the pain clinic of our hospital between January 2008 and June 2010. Variables present at the initial visit were extracted from the clinical records for regression analysis of factors related to the occurrence of PHN. The following scores for response were used: 0=no PHN after 3 months; 1=PHN present after 3 months but absent after 6 months; and 2=PHN present after 6 months. Multivariate ordered logistic regression analysis was performed to identify the predictive factors for PHN. RESULTS: Advanced age [odds ratio (OR)=2.740, confidence interval (CI)=1.110-6.761; P=0.0288] and deep pain (OR=4.244, CI=1.114-16.163; P=0.0341) at the initial visit to our outpatient pain clinic were found to be significant predictive factors for the occurrence of PHN. Diabetes mellitus (OR=3.075) and pain reduced by bathing (OR=3.389) also had high OR, although they were not significant. DISCUSSION: Our study indicates that advanced age and deep pain at the initial visit are significant predictors for PHN. Our results are considered likely to contribute to the establishment of evidence-based medicine in the optimal treatment of PHN.

[Spinal cord stimulation].

Spinal cord stimulation (SCS) is an established treatment for intractable neuropathic pain. SCS is performed using an implantable pulse generator connected to leads with electrodes positioned in the dorsal epidural space, which are then used to stimulate the ascending and descending dorsal column fibres to achieve paresthesia covering the area of pain. It is based on the Gate Control Theory, introduced by Melzack and Wall in 1965, which suggests that stimulation of large afferent fibres can inhibit pain transmission at the level of the dorsal horns. More recent studies indicate that SCS releases substance P serotonin, noradrenaline and GABA in the dorsal horns; activation of the GABAB receptor may be linked to a decrease in the release of glutamate and other excitatory amino acids, resulting in a decrease of neuropathic pain. The clinical indications for SCS are mainly peripheral vascular diseases (PVD), refractory angina, failed back surgery syndrome (FBSS), complex regional pain syndrome (CRPS) type 1 and type 2, spinal cord stenosis and neuropathic pain. The new puncture trial method is less invasive and can reduce psychological resistance of the patient for SCS manipulation.

Effect of synthetic cell-penetrating peptides on TrkA activity in PC12 cells.

As TrkA, a high-affinity receptor of nerve growth factor (NGF), is a potential target for relieving uncontrolled inflammatory pain, an effective inhibitor of TrkA has been required for pain management. To identify a specific inhibitor of TrkA activity, we designed cell-penetrating peptides combined with amino-acid sequences in the activation loop of TrkA to antagonize tyrosine kinase activity. To select a peptide inhibiting TrkA activity, we examined the effect of cell-penetrating peptides on tyrosine kinase activity of recombinant TrkA in vitro and studied their effects on NGF-stimulated neurite outgrowth and protein phosphorylation in PC12 cells. Thereafter we investigated the effect of the selected peptide on NGF-stimulated TrkA activity and the expression of transient receptor potential channel 1 in PC12 cells. The selected peptide inhibited TrkA activity, but did not inhibit tyrosine kinase activities of other receptor-type tyrosine kinases in vitro. It also suppressed NGF-stimulated responses in PC12 cells. The selected synthetic cell-penetrating peptide antagonizing TrkA function would be a candidate for inflammatory pain therapy.

Repeated exposures to hyperbaric air suppress neurite outgrowth in PC12 cells.

Hyperbaric exposure induces lesions of the CNS in scuba divers. Repeated exposures to hyperbaric air at 0.5 MPa for 30 min with short intervals suppressed NGF-stimulated neurite outgrowth, concomitant with a decrease in the protein expression of ERK in PC12 cells. Hyperbaric exposure most likely causes direct lesions of neural cells.