Visual Tract Degradation in Bilateral Normal-Tension Glaucoma-Cortical Thickness Maps and Volumetric Study of Visual Pathway Areas.

The aim of the study was to evaluate changes in the central visual pathways during the early and advanced stages of bilateral normal-tension glaucoma (NTG). METHODS: The studied groups constituted patients with bilateral normal-tension glaucoma of the same stage (n = 45) and age-matched healthy volunteers (n = 17). All patients underwent ophthalmic examination and examination on a 1.5 Tesla Magnetic Resonance Scanner (Optima 360, GE Healthcare). Volume and cortical thickness analyses were performed using the open-source automated software package FreeSurfer. RESULTS: There was a significant difference in lateral geniculate nuclei volume between the control and advanced glaucoma groups in the right hemisphere (p = 0.03) and in the left hemisphere between the early and advanced glaucoma patients (p = 0.026). The optic chiasm volume differed significantly between the control and advanced NTG groups (p = 0.0003) and between early and advanced glaucoma patients (p = 0.004). Mean cortical thickness analysis revealed a significant increase in values in the advanced glaucoma group in the right Brodmann area 17 (BA17) (p = 0.007) and right BA18 (p = 0.049) as compared to early NTG. In the left BA18 area, the mean thickness of the cortex in the early glaucoma group was significantly lower than in the control group (p = 0.03). CONCLUSIONS: The increase in the grey matter thickness in the V1 region with more-advanced glaucoma stages may reflect compensatory hypertrophy. Additionally, the regions of the brain early affected during glaucoma with reduced thickness were the right lateral occipital gyrus and left lingual gyrus. The most prominent change during the course of glaucoma was the increase in grey matter thickness in the right cuneus.

Oncological emergencies: syndrome of inappropriate antidiuretic hormone secretion (SIADH).

Excessive secretion of vasopressin in the course of Syndrome of Inappropriate Antidiuretic Hormone Secretion is a common cause of hyponatremia in cancer patients. Clinical symptoms depend on the cause, rate of change of sodium level and their absolute values. Treatment options include fluid restrictions, intravenous administration of hypertonic sodium chloride solutions, loop diuretics and vaptans. The sodium level should not be adjusted too fast, because it may lead to irreversible brain damage. The article presents pathophysiology, diagnostics and recommendations of management of this oncological emergency.