Orbital varices: imaging findings and the role of color Doppler sonography in the diagnosis.

The orbital varices are infrequent intraorbital masses, which cause intermittent, positional exophthalmos. They have low venous pressure inside which causes difficulties in detection by routine protocols of nearly all imaging modalities. Color Doppler sonography is a simple procedure that can easily detect orbital varices which avoids further evaluation in non-complicated patients. We report the imaging findings of a case of orbital varix and discuss the role of color Doppler sonography in the diagnosis and follow-up.     

Does pinealectomy affect the recovery rate after spinal cord injury?

Previous reports documented demonstrated that melatonin, a free radical scavenger, is important in protecting against oxidative stress-induced tissue damage after spinal cord injury (SCI). This study was undertaken to investigate the effects of pinealectomy (PX) and administration of exogenous melatonin after SCI in rats. These animals were randomized into six groups, each having 12 rats. Group 1 underwent laminectomy alone. Group 2 underwent laminectomy followed by SCI and received no medication. Group 3 underwent laminectomy followed by SCI and received melatonin. Group 4 underwent PX and laminectomy alone. Group 5 underwent PX and laminectomy followed by SCI and received no medication. Group 6 underwent PX and laminectomy followed by SCI and received melatonin. Melatonin (100 mg/kg) was given intraperitoneally immediately after trauma to the rats in the groups 3 and 6. PX caused a significant increase in the malondialdehyde (MDA), nitrite oxide (NO), glutathione (GSH), xanthine oxidase (XO) levels and decrease in GSH levels as compared with the control group. Trauma to the spinal cord results in significantly higher oxidative stress. Melatonin administration significantly reduced MDA, XO and NO levels, and increased GSH levels in the spinal cord after trauma. Exogenous melatonin treatment after trauma attenuated tissue lesion area and accelerated motor recovery rate. These findings suggest that reduction in endogenous melatonin after PX makes the rats more vulnerable to trauma and exogenous melatonin administration has an important neuroprotective effect on the level of the spinal cord.     

Do sodium channel blockers have neuroprotective effect after onset of ischemic insult?

OBJECTIVE: Cerebral ischemia causes a series of pathophysiologic events that may result in cerebral infarct. Some neurons are more vulnerable to ischemia, particularly pyramidal neurons in the hippocampal CA1 region. Pharmacologic intervention for treatment of cerebral ischemia aims to counteract secondary neurotoxic events or to interrupt the progression of this process. In the present study, we compare the neuroprotective effects of sodium channel blockers (mexiletine, riluzole and phenytoin) and investigate whether they have neuroprotective effect when given after ischemic insult. METHODS: A transient global cerebral ischemia model was performed in this study by clipping bilateral common carotid arteries during 45 minutes. Riluzole (8 mg/kg), mexiletine (80 mg/kg) and phenytoin (200 mg/kg) were injected into the rats intraperitoneally 30 minutes before or after reperfusion. Lipid peroxidation levels and cerebral water contents were evaluated 24 hours after ischemia. Histopathologic assessment of hippocampal region was determined 7 days after ischemia. RESULTS: Riluzole, mexiletine and phenytoin treatment after global ischemia significantly decreased water content of the ischemic brain (p<0.05 for each). No significant difference was observed in cerebral edema among the drug treatment groups (p>0.05). When pre-treatment and post-treatment groups were compared with each other, only riluzole pre-treatment group revealed better result for cerebral edema (p<0.05). Pre-treatment with these drugs revealed significantly better results for the malonyldialdehyde (MDA) level and the number of survival neuron on the hippocampal region than the post-treatment groups. CONCLUSION: It is demonstrated that riluzole, mexiletine and phenytoin are potent neuroprotective agents in the rat model of transient global cerebral ischemia, but they are more effective when given before onset of the ischemia.     

THE EFFECT OF TRAVOPROST AND BI-MATOPROST ON BLOOD FLOW VELOCI-TY OF THE RETROBULBAR VESSELS

Objective: To investigate the effects of topical travoprost 0.004% and topical bimatoprost 0.03% on retrobulbar blood flow (RBF). Methods: Nineteen young healthy men without any known ocular or systemic disorder were enrolled in this prospective, double-masked, randomized, cross-over study. Baseline RBF mea-     

Induction chemotherapy with cisplatin and 5-fluorouracil followed by chemoradiotherapy or radiotherapy alone in the treatment of locoregionally advanced resectable cancers of the larynx and hypopharynx: results of single-center study of 45 patients

BACKGROUND: Induction chemotherapy with cisplatin and fluorouracil and radiotherapy is an effective alternative to surgery in patients with carcinoma of the larynx and hypopharynx who are treated for organ preservation. METHODS: We designed a protocol to evaluate the possibility of organ preservation in patients with advanced, resectable carcinoma of the larynx and hypopharynx. Forty-five eligible patients who were followed up between April 1999 and May 2001 were enrolled. Initially, these patients were treated with two cycles of induction chemotherapy consisting of cisplatin, 20 mg/m2/day on days 1 to 5, and 5-fluorouracil, 600 mg/m2/day by continuous infusion on days 1 to 5. Patients who had a complete response to chemotherapy were treated with definitive radiotherapy; patients who had a partial response to chemotherapy were treated with chemoradiotherapy. Cisplatin, 35 mg/m2/week, was introduced throughout the duration of radiotherapy. Patients who had no response or progressive disease underwent surgery with postoperative radiotherapy. Patients with N2 or N3 positive lymph nodes underwent neck dissection after the treatment. RESULTS: The mean age was 56.6 years (range, 34-75 years). The overall response rate to induction chemotherapy was 71.1%, with a 17.8% complete response rate and 53.3% partial response rate. With a median follow-up of 13.7 months, 23 (51.1%) of all patients and 63.3% of surviving patients have had a preservation of the larynx or hypopharynx and remain disease free. The most common toxicities were nausea and vomiting and mucositis. CONCLUSION: Organ preservation, with multimodality treatment, may be achievable in some of the patients with resectable, advanced larynx or hypopharynx cancers without apparent compromise of survival.     

Graded visual attention modulates brain responses evoked by task-irrelevant auditory pitch changes

Previous studies suggested that auditory change-specific neural responses are attention-independent and reflect central auditory processing. The automaticity of the brain's response to infrequent changes in pitch within a series of auditory tone pips was examined in parallel functional magnetic resonance imaging (fMRI) and event-related potential (ERP) studies. Subjects performed a continuous perceptual-motor visual tracking task at two levels of difficulty while simultaneously hearing a series of task-irrelevant standard tone pips and infrequent pitch-deviant tones. fMRI results revealed that the unattended pitch-deviant tones strongly activated superior temporal and frontal cortical regions. These activations were significantly modulated by the tracking difficulty of the primary task. ERP results revealed that the amplitude of the scalp-negative component evoked by deviant tones (MMN) was attenuated during the more difficult tracking task. Our results demonstrate that the brain's response to task-irrelevant sensory changes is strongly influenced by intermodal attentional demands.     

Nocardial endophthalmitis and subretinal abscess: CT and MR imaging features with pathologic correlation: a case report

Ocular nocardiosis is a rare but potentially aggressive process. Clinically, it can mimic other disease entities, including neoplasia and other types of infection. We present a case of nocardial panophthalmitis progressing to subretinal abscess and emphasize the radiologic and clinical features.     

Idiopathic isolated clitoromegaly: A report of two cases

Background  

Clitoromegaly is a frequent congenital malformation, but acquired clitoral enlargement is relatively rare.