Optical coherence tomography study of experimental anterior ischemic optic neuropathy and histologic confirmation.

PURPOSE: The optic nerve is part of the central nervous system, and interruption of this pathway due to ischemia typically results in optic atrophy and loss of retinal ganglion cells. In this study, we assessed in vivo retinal changes following murine anterior ischemic optic neuropathy (AION) by using spectral-domain optical coherence tomography (SD-OCT) and compared these anatomic measurements to that of histology. METHODS: We induced ischemia at the optic disc via laser-activated photochemical thrombosis, performed serial SD-OCT and manual segmentation of the retinal layers to measure the ganglion cell complex (GCC) and total retinal thickness, and correlated these measurements with that of histology. RESULTS: There was impaired perfusion and leakage at the optic disc on fluorescein angiography immediately after AION and severe swelling and distortion of the peripapillary retina on day-1. We used SD-OCT to quantify the changes in retinal thickness following experimental AION, which revealed significant thickening of the GCC on day-1 after ischemia followed by gradual thinning that plateaued by week-3. Thickness of the peripapillary sensory retina was also increased on day-1 and thinned chronically. This pattern of acute retinal swelling and chronic thinning on SD-OCT correlated well with changes seen in histology and corresponded to loss of retinal ganglion layer cells after ischemia. CONCLUSIONS: This was a serial SD-OCT quantification of acute and chronic changes following experimental AION, which revealed changes in the GCC similar to that of human AION, but over a time frame of weeks rather than months.

Sign and pseudo-sign of Leser-Trélat: case reports and a review of the literature.

BACKGROUND: Leser-Trélat is distinguished by a rare paraneoplastic sign that is characterized by the sudden eruption of multiple seborrheic keratoses (SKs), associated with underlying internal malignancies. Similar non-malignancy-associated SK eruptions are referred to as the "pseudo-sign of Leser-Trélat" (PLT). OBJECTIVE: Two cases of rapid SK eruptions, one the sign of Leser-Trélat (SLT) and one PLT, are presented, and the literature on SLT and PLT is reviewed. METHODS: A literature review of SLT/PLT was performed by searching the PubMed database for all related English published cases. RESULTS: We identified 109 cases of SLT and 12 cases of PLT, with a mean patient age of 61.8 years. SK eruptions were observed before (68.3%), after (22.1%), and at the time of (9.6%) malignancy diagnosis. The malignancy most frequently associated with SLT was gastric adenocarcinoma. The most common anatomical location of SK eruptions was the trunk (18.9%). Frequently reported associated signs and symptoms included pruritus (52%) and acanthosis nigricans (38.7%). The most common treatment included surgery (35.8%), chemotherapy (26.9%), and radiation therapy (26.9%). Treatment resulted in clinical improvement (45%), no change (30%), exacerbation (15%), or initial improvement followed by exacerbation of SKs. Patient outcomes included disease stability/ improvement (48.4%), recurrence (9.7%), exacerbation/metastasis/new malignancy (4.8%), and death (37.1%). LIMITATIONS: This was a retrospective study and excluded non-English published cases. CONCLUSION: This review updates the existing SLT literature and emphasizes the presence of PLT. Clinicians should be aware that SK eruptions may be early manifestations of an internal malignancy or other pathology. To our knowledge, this is the first review examining both SLT and PLT.