Objectives: This study investigates the histology of the middle layer of the eye in rabbit fish Siganus javus. Methods: The eyes of twelve healthy fish were enucleated and histologic sections of 6μ were prepared. The sections were stained with Hematoxyline & Eosine (H&E) and Masson trichrom then were observed using light microscopy. Results: The middle or vascular layer consisted of the choroid and iris. The result revealed that the choroid coat was subdivided into five laminae: 1. Suprachoroid layer 2. Substina propria included choroidal gland or retemirabile, melanoid layers and connective tissue 3. Fibrouse layer 4. Choriocapillary layer 5. Separator layer. The extension of the choroid coat into the anterior compartment made the iris which mainly composed of connective tissue, blood vessels, melanocyte and a smooth muscle at the posterior part of the iris, adjacent to the pupil. The choroid coat did not continue rostrally adjacent to the cornea. Suspensory apparatus of the lens of the Siganus javus eye consisted of a dorsal suspensory ligament and a ventral retractor muscle. Conclusions: The diversity and deviation in the detail of microscopic structures in the eye of teleosts is approved through this microscopic study in middle layer of rabbit fish eye however the five differentiated parts of choroid were distinguished as in many telelost species.

Background: and Purpose Acute necrotizing encephalopathy (ANE) is a rare neurological disorder that is often associated with viral infections. Since the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a few COVID-19-associated ANE cases have been reported. Since very little is known about ANE, the present study aimed to determine the clinical, biochemical, and radiological characteristics of affected patients. Methods: A search was conducted on PubMed, Scopus, Embase, and Web of Science databases for articles published up to August 30, 2022 using relevant keywords. Case reports and series in the English language that reported ANE in adult patients with COVID-19 confirmed by reverse transcription polymerase chain reaction were included in this study. Data on the demographic, clinical, laboratory, and radiological characteristics of patients were extracted and analyzed using the SPSS software (version 26). Results: The study included 30 patients (18 males) with COVID-19 and ANE who were aged 49.87±18.68 years (mean±standard deviation). Fever was the most-prevalent symptom at presentation (66.7%). Elevated C-reactive protein was observed in the laboratory assessments of 13 patients. Computed tomography and magnetic resonance imaging were the most-common radiological modalities used for brain assessments. The most commonly prescribed medications were methylprednisolone (30%) and remdesivir (26.7%). Sixteen patients died prior to discharge. Conclusions The diagnosis of COVID-19-associated ANE requires a thorough knowledge of the disease. Since the clinical presentations of ANE are neither sensitive nor specific, further laboratory and brain radiological evaluations will be needed to confirm the diagnosis. The suspicion of ANE should be raised among patients with COVID-19 who present with progressive neurological symptoms.