Greater occipital nerve excision for occipital neuralgia refractory to nerve decompression.

BACKGROUND: Patients who undergo occipital nerve decompression for treatment of migraine headaches due to occipital neuralgia have already exhausted medical options for treatment. When surgical decompression fails, it is unknown how best to help these patients. We examine our experience performing greater occipital nerve (GON) excision for pain relief in this select, refractory group of patients. METHODS: A retrospective chart review supplemented by a follow-up survey was performed on all patients under the care of the senior author who had undergone GON excision after failing occipital nerve decompression. Headache severity was measured by the migraine headache index (MHI) and disability by the migraine disability assessment. Success rate was considered the percentage of patients who experienced a 50% or greater reduction in MHI at final follow-up. RESULTS: Seventy-one of 108 patients responded to the follow-up survey and were included in the study. Average follow-up was 33 months. The success rate of surgery was 70.4%; 41% of patients showed a 90% or greater decrease in MHI. The MHI changed, on average, from 146 to 49, for an average reduction of 63% (P < 0.001). Migraine disability assessment scores decreased by an average of 49% (P < 0.001). Multivariate analysis revealed that a diagnosis of cervicogenic headache was associated with failure of surgery. The most common adverse effect was bothersome numbness or hypersensitivity in the denervated area, occurring in up to 31% of patients. CONCLUSIONS: Excision of the GON is a valid option for pain relief in patients with occipital headaches refractory to both medical treatment and surgical decompression. Potential risks include failure in patients with cervicogenic headache and hypersensitivity of the denervated area. To provide the best outcome to these patients who have failed all previous medical and surgical treatments, a multidisciplinary team approach remains critical.

Evaluation of a screening test for detection of giardia and cryptosporidium parasites.

The Giardia/Cryptosporidium Chek test (TechLab, Inc.), a screening test for Giardia and Cryptosporidium, was evaluated with 136 fecal samples. Using the results of the Giardia II test and Cryptosporidium II test as gold standards, it was 98.4% sensitive and 100% specific and had positive and negative predictive values of 98.7% and 99.3%.