The symptomatological and histopathological studies on the terrestrial snail Eobania vermiculata Müller infected with the parasitic nematode Rhabditis sp. showed that there is a great evidence of a direct effect of the nematodes on its movement, behavior and tissues of the snail before death. These symptoms were summarized in slow slipping, turning of the headfoot direction while slipping and suppressive feeding. Histological investigation revealed that focal cellular reaction was formed around the developing larvae in the snail tissues particularly the headfoot region. Capsules of different sizes were also developed around the nematode larvae.

BACKGROUND: Horner's syndrome (HS) is a rare postoperative complication after anterior cervical discectomy and fusion (ACDF). OBJECTIVE:This study aims to assess the incidence, patient's demography and surgical approach, outcomes and possible predictive factors for the occurrence of Horner's syndrome following the anterior approach for cervical discectomy. METHODS:A retrospective study of 820 patients who had single or successive two levels ACDF for cervical degenerative disc disease using PolyEtherEtherKetone (PEEK) cages between 2016 and 2019 was conducted. Charts were reviewed to identify patients with postoperative occurrence of Horner's syndrome with a follow up period of 12 months. Outcome for ptosis, being the most important factor, was classified according to margin to reflex distance. RESULTS:Forty patients had postoperative HS following ACDF out of 820 patients (4.8%). Around 67% of the patients with HS had single level discectomy, and the most frequent level was C5-6. The average age of patients with HS was 47 years, 55% were males, 33% were smokers and 20% were diabetics. Radiculopathy was more frequent than myelopathy. When anterior plate fixation system was used the incidence of Horner's syndrome was higher (60%). Improvement or complete resolution occurred in 90% of the cases.CONCLUSION: Using anterior plating system during ACDF increases the risk of Horner's syndrome. In most of the cases, Horner's syndrome is a temporary clinical manifestation that is managed conservatively. Rarely, surgical repair for ptosis might be required.