Local anesthetics that are commonly used in ophthalmic surgery(0.5% bupivacaine hydrochloride, 2.0% lidocaine hydrohloride, 0.38% bupivacaine-1.0% lidocaine-1:100,000 epinephrine mixture) were injected into the retrobulbar space of rabbit eyes. Physiologic saline was injected into that spaces in control group in the same manner. All three anesthetics produced degeneration of the extraocular muscles to a varying extent. Muscle degeneration was followed by rgeneration of the damaged muscle fibers. In addition to muscle damage, severe damage to harderian gland was also seen in lidocaine-injected group. The optic nerve was not affected. With these findings in rabbits, it is hypothesized that the temporary diplopia and ptosis sometimes seen in patients after ophthalmic surgery might be due to anestheticsinduced damage to the extraocular muscles.
Anesthesia* ; Anesthetics ; Anesthetics, Local ; Animals ; Bupivacaine ; Diplopia ; Epinephrine ; Harderian Gland ; Humans ; Lidocaine ; Muscles* ; Optic Nerve ; Rabbits

Positron emission tomography (PET) using 2-deoxy-2-[18F] fluoro-D-glucose (FDG) as a radioactive tracer is a useful technique for in vivo brain imaging. However, the anatomical and physiological features of the Harderian gland limit the use of FDG-PET imaging in the mouse brain. The gland shows strong FDG uptake, which in turn results in distorted PET images of the frontal brain region. The purpose of this study was to determine if a simple surgical procedure to remove the Harderian gland prior to PET imaging of mouse brains could reduce or eliminate FDG uptake. Measurement of FDG uptake in unilaterally adenectomized mice showed that the radioactive signal emitted from the intact Harderian gland distorts frontal brain region images. Spatial parametric measurement analysis demonstrated that the presence of the Harderian gland could prevent accurate assessment of brain PET imaging. Bilateral Harderian adenectomy efficiently eliminated unwanted radioactive signal spillover into the frontal brain region beginning on postoperative Day 10. Harderian adenectomy did not cause any post-operative complications during the experimental period. These findings demonstrate the benefits of performing a Harderian adenectomy prior to PET imaging of mouse brains.
Animals ; Brain/*metabolism/radionuclide imaging ; Fluorodeoxyglucose F18/*diagnostic use ; Frontal Lobe/metabolism/radionuclide imaging ; Harderian Gland/metabolism/radionuclide imaging/*surgery ; Mice ; Mice, Inbred BALB C ; Neuroimaging/standards/*veterinary ; Positron-Emission Tomography/*veterinary ; Radiopharmaceuticals/*diagnostic use