Increased Intracranial Pressure Damages Optic Nerve Structural Support.

Optic nerve sheath diameter (ONSD) is used clinically as a noninvasive measure for elevated intracranial pressure (ICP). This study had two purposes: to investigate the immediate effects optic nerve sheath (ONS) dilation post-ICP increase on trabecular fibers connecting the optic nerve to the ONS and to document any changes in these fibers 30 days post-increased ICP. In a swine model, ICP was increased by inflating a Foley catheter balloon in the epidural space. Three control pigs received the catheter insertion without inflation (no increase in ICP) and four experimental pigs received the catheter with inflation (increased ICP). The control and two randomly selected pigs with increased ICP were euthanized immediately after the procedure. The two other pigs were euthanized 30 days post-catheter inflation. For all pigs, the ONS was removed and imaged using a scanning electron microscope, calculating percent porosity values. Porosity values for the experimental groups (Immediately measured [IM] µ = 0.5749; Delayed measured [DM] µ = 0.5714) were larger than the control group (µ = 0.4336) and statistically significant (IM vs. Control, p = 0.0018; DM vs. Control, p = 0.0092). There was no significant difference (p = 0.9485) in porosity of the DM group when compared with the IM group. This study demonstrated that the trabecular fibers immediately post-increased ICP (ONS dilation) were more porous than the control and remained statistically different (more porous) after 30 days. These results suggest a structural change that occurs in the ONS with elevations in ICP.

Rapidly Lethal Ruptured Hepatocellular Carcinoma With Disseminated Peritoneal Carcinomatosis on FDG PET/CT.

Hepatocellular carcinoma (HCC) is the fourth most common cause of cancer-related death worldwide. Hepatocellular carcinoma commonly metastasizes to lungs, lymph nodes, and bone. Although HCC usually occurs in setting of chronic liver disease due to alcoholism or HBV/HCV infection, the incidence of HCC arising from nonalcoholic steatohepatitis is increasing. We present a very unusual initial presentation of occult HCC with peritoneal carcinomatosis secondary to liver rupture in a 70-year-old man with known nonalcoholic steatohepatitis-cirrhosis, best appreciated on FDG PET/CT. Our patient died a few days later. Tumor rupture is a rare but usually rapidly lethal complication of HCC.