Modified Pure Endoscopic Approach to Pineal Region: Proof of Concept of Efficient and Inexpensive Surgical Model Based on Laboratory Dissections.

OBJECTIVE: In recent decades endoscopic techniques have been increasingly used in neurosurgery as they may offer a valuable close-up view of the working area through a minimally invasive surgical corridor. Herein, we present an inexpensive and efficient endoscopic surgical model using a borescope, which was used for a "modified pure endoscopic approach" to the pineal region. METHODS: A borescope video camera was connected to a 16-inch personal computer monitor. A standard midline suboccipital craniotomy was performed on 2 cadaveric heads in the Concorde position. Then, a "borescopic" supracerebellar infratentorial approach was executed, thus reaching the pineal region, which was exposed through an extensive arachnoid dissection. RESULTS: Using the previously described model, we were able to provide excellent exposure of the main neurovascular structures of the pineal region, as shown by the intraoperative videos. In 1 specimen we identified an incidental pineal cyst that was meticulously dissected and removed. CONCLUSIONS: Our proposed "borescopic" surgical model may represent an inexpensive and efficient alternative to conventional endoscopic techniques and could be used for training purposes, as well as even for clinical procedures, after a proper validation, particularly in economically challenging environments.

Autoradiographic assessment of pineal gland glucose utilization and capillary permeability in the unanesthetized rat.

Pineal gland glucose utilization (GU) and capillary permeability (CP) were measured in unanesthetized rats, using complementary quantitative autoradiographic techniques. GU values within the pineal tissue were homogeneously distributed around 70 mumol of glucose/100 g each min, i.e., they were approximately 30% lower than in the cortical gray structures. The blood-to-brain transfer constant of [14C]-alpha-aminoisobutyric acid, as an index of CP, was up to ten orders of magnitude higher than that for the rest of the brain. These measurements were carried out at that point in the circadian rhythm that corresponds to the minimum level of neurosecretory activity of the pineal gland.