Estimation of postmortem interval (PMI) is one of the important research contents in forensic pathology, and it has always been the focus and hot spot of research work. In recent years, scholars at home and abroad have made some research progress in estimating PMI by using ocular tissue. After death, the changes of cornea, aqueous humor, iris, lens, vitreous humor and retina all show time sequence change rule highly related to PMI. This paper reviews the research progress of PMI estimation based on the morphological, biochemical, molecular and genetic material changes of different ocular tissue structures after death, and discusses the existing problems and development trends.
Humans ; Postmortem Changes ; Time Factors ; Autopsy ; Vitreous Body ; Forensic Pathology

proliferative vitreoretinopathy (PVR) is the most common cause of failure in retinal reattachment surgery. Three different procedures were performed in 20 pigmented rabbits to devise a simple model to induce experimental PVR. Rabbits were assigned randomly to three groups (I, II, and III). Group I rabbits (5 rabbits, 10 eyes) rereived normal saline into the vitreous cavity, after an iatrogenic retinal tear was made. In group II rabits (8 rabbits, 8 eyes), a suspension of retinal pigment epithelium (RPE) and choroid from the left eye was transferred into the vitreous cavity of the right eye. In group III rabbits (7 rabbits, 7 eyes), a suspension of RPE and choroid from the left eye was transferred into the vitreous cavity of the right eye after an iatrogenic retinal tear was made. The fundus was observed for 2 months with an indirect ophthalmoscope. The incidence of retinal detachment in group I was zero (O/IO), that of group II was 37.5% (3/8), and that of group III was 85.7% (6/7). Electron microscopic findings of the vitreous strand of one eye of group II showed a central melanocytic core, peripheral fibroblasts, and intercellular collasen fibril. Electron microscopic findings in one eye of group III revealed a subretinal membrane composed of suspected RPE and glial cells.
Animals ; *Disease Models, Animal ; Pigment Epithelium of Eye/pathology ; Rabbits ; Retinal Diseases/*etiology ; Vitreous Body/pathology

PURPOSE: To evaluate posterior vitreous structures using swept-source (SS) optical coherence tomography (OCT) with en face imaging. METHODS: We retrospectively reviewed OCT images of healthy individuals who did not have intra-ocular disease. We obtained high-definition horizontal and vertical line scans crossing the fovea and 3D scans using SS-OCT, with the 3D scan centered between the fovea and the optic-nerve head. An enhanced vitreous visualization function was used to highlight vitreous structures. En face mode was used to measure the area of Martegiani (AM) and bursa premacularis (BP). We performed all measurements using a built-in function of the viewing software. RESULTS: We enrolled 24 eyes from 12 healthy individuals. The mean patient age was 28.7 ± 4.6 years (range, 24 to 39 years). The mean AM and BP areas were 5.73 ± 0.88 and 18.76 ± 6.95 mm2, respectively. In en face imaging, AM shape was most frequently a vertical oval (18 / 22, 81.8%), while the predominant BP shape was round (16 / 20, 80.0%). AM was in contact with the optic disc, either at the temporal-disc margin (13 eyes, 59.1%) or the nasal optic-disc margin (9 eyes, 40.9%). CONCLUSIONS: Posterior vitreous structures, such as AM and BP, were readily visualized using en face imaging with SS-OCT. Investigating normal vitreous configuration might help in understanding changes in vitreous structures associated with retinal pathology.
Head ; Humans ; Pathology ; Retinaldehyde ; Retrospective Studies ; Tomography, Optical Coherence* ; Vitreous Body

Cryotherapy is implicated for inducing or aggravating proliferative vitreoretinopathy (PVR) by releasing retinal pigment epithelial (RPE) cells. These are based on the fact that PVR rarely occurs in a non-operated eye, and many of the PVR patients have received cryotherapy during surgery. Nonetheless, eyes with diathermy also developed PVR, and although there have been many experiments, the effect of cryotherapy on inducing PVR has not been proven experimentally in the living eye. We made retinal tears in living rabbit eyes, and applied cryotherapy on one eye of each rabbit. The result was compared histologically with the contralateral noncryothermized control eye. There was no statistically significant difference between the two groups concerning the migration of RPE, and the proliferation of RPE. Although the formation of an epiretinal membrane was more obvious in the cryothermized group, the difference was not statistically significant.
Animals ; Cell Division ; *Cryosurgery/adverse effects ; Rabbits ; Retinal Detachment/*pathology ; Retinal Perforations/*pathology ; Vitreous Body/*pathology/surgery

Postmortem chemistry is becoming more and more essential in routine forensic pathology and has made considerable progress over the past years. Biochemical analyses of vitreous humor, blood, urine and cerebrospinal fluid may provide important information in determining the cause of death or in elucidating forensic issues. Postmortem chemistry may be essential for the determination of cause of death when morphological methods (diabetes mellitus, alcoholic ketoacidosis and electrolytic disorders) cannot detect the pathophysiological changes involved in the death process. It can also provide many information in other forensic situations, including myocardial ischemia, sepsis, inflammation, infection, anaphylaxis and hormonal disturbances. The most recent relevant research advances on glucose metabolism, liver function, cardiac function, renal function, sepsis, inflammation, infection, anaphylaxis and hormonal aspect are hereby reviewed.
Anaphylaxis ; Autopsy/trends* ; Biomarkers/analysis* ; Body Fluids/chemistry* ; Death ; Diabetes Mellitus ; Forensic Pathology/methods* ; Humans ; Postmortem Changes ; Sepsis ; Vitreous Body

No abstract available.
Child ; Cornea/*abnormalities ; Cysts/*diagnosis ; Eye Abnormalities/*diagnosis ; Eye Diseases/*diagnosis ; Female ; Humans ; Visual Acuity/physiology ; Vitreous Body/*pathology

OBJECTIVE: To investigate the correlation between postmortem interval (PMI) and the changes of electrical conductivity in vitreous humor in rabbits after death. METHODS: The changes of electrical conductivity in vitreous humor in rabbits were measured using the conductivity meter under 30 degrees C during 0-48 hours and 20 degrees C during 0-120 hours after death. RESULTS: Electrical conductivity in vitreous humor in rabbits increased gradually under 30 degrees C and 20 degrees C from 0 to 48 hours and from 0-120 hours after death. The formulae of the relationship between PMI and conductivity under 30 degrees C and 20 degrees C were obtained by statistical analysis and the correlation coefficients were 0.970 and 0.983 (both P < 0.01), respectively. CONCLUSION The increase of electrical conductivity in vitreous humor in rabbits after death may be used as the relatively objective parameter for PMI estimation.
Animals ; Electric Conductivity ; Female ; Forensic Pathology ; Male ; Postmortem Changes ; Rabbits ; Random Allocation ; Time Factors ; Vitreous Body/physiopathology*

Estimation of postmortem interval (PMI) is one of the problems that need to be solved for forensic examination of the dead body. Accurate estimation of PMI has great values to criminal investigation and trial. The levels of chemical components in human vitreous humor are changed with time after death, which can help estimate the PMI. The levels of certain chemical components, such as potassium, magnesium, ammonia, urea, creatinine, uric acid, hypoxanthine, lactic acid and so on, in human vitreous humor will gradually increase with time after death, while others such as calcium, sodium, enzymes, glucose, vitamin C and so on will decrease. The updates and advances in those studies were reviewed in this article.
Calcium/analysis* ; Forensic Pathology ; Humans ; Magnesium/analysis* ; Postmortem Changes ; Potassium/analysis* ; Sodium/analysis* ; Time Factors ; Vitreous Body/chemistry*

Antineoplastic Agents, Alkylating ; administration & dosage ; Child ; Humans ; Intravitreal Injections ; Male ; Melphalan ; administration & dosage ; Neoplasm Seeding ; Retinal Neoplasms ; drug therapy ; pathology ; Retinoblastoma ; drug therapy ; pathology ; Vitreous Body ; pathology

Hereditary vitreoretinopathies are potentially blinding inherited disorders characterized by an abnormal-appearing vitreous gel and associated retinal changes. Four of these disorders, Stickler's syndrome, Wagner's disease, erosive vitreoretinopathy, and Goldmann-Favre syndrome, exhibit marked syneresis of the vitreous gel. Erosive vitreoretinopathy has associated retinal pigment epithelial changes, poor night vision, visual field defects, and abnormal electroretinographic findings; symptoms not found in Stickler's syndrome. A 36-year-old man with progressive visual loss and a visual field defect had no systemic disease. His vitreous cavity was liquefied. Vitreous strands and a cataract were found in both eyes. Pronounced RPE degeneration was found superotemporally in both eyes and a bullous rhegmatogenous retinal detachment in the left eye accompanied two retinal tears. His visual field showed a ring scotoma in both eyes and the ERG finding was abnormal. We report one case of erosive vitreoretinopathy with retinal pigment epithelial changes, rhegmatogenous retinal detachment, visual field defects, abnormal electroretinographic findings, marked vitreous syneresis and cataract. These symptoms are distinct from previously described entities.
Adult ; Case Report ; Electroretinography ; Eye Diseases/*pathology ; Human ; Male ; Ophthalmologic Surgical Procedures/methods ; Retinal Diseases/*pathology ; Treatment Outcome ; Vision Disorders/diagnosis ; Visual Fields ; Vitreous Body/*pathology