Digital subtraction angiography-guided peripheral nerve stimulation via the foramen rotundum for refractory trigeminal postherpetic neuralgia: a case report and literature review

The incidence and morbidity of herpes zoster (HZ) and HZ ophthalmicus (HZO), and the potential impact of varicella vaccine on their epidemiology. Herpes zoster affects 20% to 30% of the population at some point in their lifetime; approximately 10% to 20% of these individuals will have HZO. The peer-reviewed literature published from 1865 to the present was reviewed. Herpes zoster is the second clinical manifestation of varicella-zoster virus (VZV). The incidence and severity of HZ increase with advancing age. Varicella-zoster virus-specific cell-mediated immunity, which keeps latent VZV in check and is boosted by periodic reexposure to VZV, is an important mechanism in preventing VZV reactivation as zoster. Thus, widespread varicella vaccination may change the epidemiology of HZ. Herpes zoster ophthalmicus occurs when HZ presents in the ophthalmic division of the fifth cranial nerve. Ocular involvement occurs in approximately 50% of HZ patients without the use of antiviral therapy. There is a long list of complications from HZ, including those that involve the optic nerve and retina in HZO, but the most frequent and debilitating complication of HZ regardless of dermatomal distribution is postherpetic neuralgia (PHN), a neuropathic pain syndrome that persists or develops after the zoster rash has resolved. The main risk factor for PHN is advancing age; other risk factors include severe acute zoster pain and rash, a painful prodrome, and ocular involvement. Many cases of HZ, HZO, and PHN can be prevented with the zoster vaccine. Vaccination is key to preventing HZ, HZO, and PHN, but strategies for both varicella and HZ vaccines will need to be evaluated and adjusted periodically as changes in the epidemiology of these VZV diseases become more evident.

Background Data on the epidemiology and cost of herpes zoster (HZ) and post-herpetic neuralgia (PHN) in Italy are limited. This retrospective, population-based study was designed to determine the incidence of HZ and the proportion developing PHN in Italy and the associated medical resource utilisation and costs. It focused primarily on immunocompetent patients aged ≥50 years who would be eligible for preventive vaccination. Method Data were extracted from a primary-care database and national hospital-discharge records covering four major regions in Italy for 2003-2005. Cases of HZ and PHN (1 and 3 months' duration; PHN1 and PHN3) were identified by ICD9-CM codes and, additionally for PHN, prescription of neuropathic pain medication. Results Over 3 years, 5675 incident cases of HZ were documented in adults, of which 3620 occurred in immunocompetent patients aged ≥50 years (incidence of 6.31 per 1000 person-years [95% CI: 6.01-6.62]). Of the immunocompetent patients aged ≥50 years with HZ, 9.4% (95% CI: 8.2-10.7) and 7.2% (95% CI: 6.2-8.2) developed PHN1 and PHN3, respectively. Increasing age, female sex, and being immunologically compromised conferred increased risk for both HZ and PHN. Overall, about 1.3% of HZ and almost 2% of PHN cases required inpatient care, with 16.9% of all HZ-related hospitalisations due specifically to PHN. In patients aged ≥50 years, mean stay was 7.8 ± 5.4 days for HZ and 10.2 ± 8.6 days for PHN, and direct costs associated with inpatient care were more than 20 times outpatient costs per HZ case (mean ± SD: €2592 ± €1313 vs. €122.68 ± €97.51) and over 5 times more per episode of PHN (mean ± SD: €2806 ± €2641 vs. €446.10 ± €442.97). Total annual costs were €41.2 million, of which €28.2 million were direct costs and €13.0 million indirect costs. Conclusions This study, the largest to date on the epidemiology and economic impact of HZ and PHN in Italy, confirms the considerable disease and economic burden posed by HZ. As HZ and PHN disproportionately affect the elderly, without intervention this problem is likely to grow as the proportion of elderly in the Italian population continues to increase.