Piezosurgery for safe and efficient petrous bone cutting in cerebellopontine angle and petroclival meningioma surgery.

Intradural petrous bone drilling has become a widespread practice, providing extended exposure in the removal of cerebellopontine angle (CPA) or petroclival tumors. Adjacent neurovascular structures are at risk, however, when drilling is performed in this deep and narrow area. Hence, this study evaluates the use of Piezosurgery (PS) as a non-rotating tool for selective bone cutting in CPA surgery. A Piezosurgery® device was used in 36 patients who underwent microsurgery for extra-axial CPA or petroclival tumors in our Neurosurgical Department between 2013 and 2019. The clinical and radiological data were retrospectively analyzed. The use of PS was evaluated with respect to the intraoperative applicability and limitations as well as efficacy and safety of the procedure. Piezosurgical petrous bone cutting was successfully performed in the removal of meningiomas or extra-axial metastases arising from the dura of the petroclival region (21 patients) or petrous bone (15 patients). PS proved to be very helpful in the deep and narrow CPA region, considerably reducing the surgeon's distress toward bone removal in close proximity to cranial nerves and vessels in comparison to common rotating drills. The use of PS was safe without injuries to neurovascular structures. Gross total resection was achieved in 67% of petroclival and 100% of petrous bone tumors. Piezosurgery proved to be an effective and safe method for selective petrous bone cutting in CPA surgery avoiding rotating power and associated risks. This technique can particularly be recommended for bone cutting in close vicinity to critical neurovascular structures.

High-Resolution Gadolinium-Enhanced MR Cisternography Using Compressed-Sensing T1 SPACE Technique for Detection of Intracranial CSF Leaks.

In patients with CSF rhinorrhea, accurate identification of the CSF leakage site is crucial for surgical planning. We describe the application of a novel gadolinium-enhanced high-resolution 3D compressed-sensing T1 SPACE technique for MR cisternography and compare findings with CT cisternography and intraoperative results. In our pilot experience with 7 patients, precise detection of CSF leaks was feasible using compressed-sensing T1 SPACE, which appeared to be superior to CT cisternography.

Integrity of dural closure after autologous platelet rich fibrin augmentation: an in vitro study.

BACKGROUND: Watertight closure of the dura mater is fundamental in neurosurgery. Besides the classical suturing techniques, a variety of biomaterials have been proposed as sealants. Platelet rich fibrin (PRF) is an autologous biomaterial which can readily be obtained through low-speed centrifugation of patient's own blood. It is rich in fibrin, growth factors, leucocytes and cytokines and has shown adhesive properties while promoting the physiological wound healing process. In this study, we investigated the effect of applying PRF in reinforcing the watertight dura mater closure. METHODS: We created an in vitro testing device, where the watertight dura mater closure could be hydrostatically assessed. On 26 fresh harvested bovine dura maters, a standardised 20-mm incision was closed with a running suture, and the leak pressure was measured first without (primary leak pressure) and then with PRF augmentation (secondary leak pressure). The two groups of measurements have been statistically analysed with the Student's paired t test. RESULTS: The "running suture only group" had a leak pressure of 10.5 ± 1.2 cmH2O (mean ± SD) while the "PRF-augmented group" had a leak pressure of 47.2 ± 2.6 cm H2O. This difference was statistically significant (p < 0.001; paired t test). CONCLUSIONS: Autologous platelet rich fibrin augmentation reliably reinforced watertight closure of the dura mater to a > 4-fold increased leak pressure after failure of the initial standard running suture technique.

Piezosurgical lateral suboccipital craniectomy and opening of the internal auditory canal in the rat.

AIM: Rotating burs (RB), routinely used in skull base and cerebellopontine angle (CPA) surgery for craniotomy and opening of the internal auditory canal (IAC) carry some risks for neurovascular tissue due to their rotating power. This paper describes the use of piezosurgery (PS), which selectively cuts bone with preservation of soft tissue, in lateral suboccipital craniectomy and opening of the IAC in the rat. METHODS: A lateral suboccipital craniectomy and opening of the bony IAC were performed with the Mectron® piezosurgical device under microsurgical conditions in the anesthezised rat. The piezosurgical device was evaluated with respect to practicability, safety, preciseness of craniectomy and IAC opening, and preservation of adjacent neurovascular tissue. The operation procedure is described in detail. RESULTS: The present work shows that PS allows easy, safe and precise bone cutting with no injury to neurovascular tissue, such as dura, transverse or sigmoid sinus, brain, and cranial nerves. No complications were noted during the procedure. Due to the absence of rotating power near neurovascular structures the drilling process was easy and comfortable for the surgeon. CONCLUSION: PS proved to be a safe, precise and easy to handle tool to perform suboccipital craniectomy and opening of IAC in the rat. Since PS makes the drilling process safer and more comfortable compared to a rotating bur it may be used instead of rotating burs in all scientific applications in animal models where a safe removal of bone near delicate nervous or soft tissue structures is essential.

[Ulceration on the bridge of the nose in a young adult]. / Ulzeration am Nasenrücken eines jungen Erwachsenen.

Nasal dermoid sinus represents an entity of embryonic malformation of the midface. The diagnostic approach includes computed tomography for assessment of the bony components and magnetic resonance imaging for assessment of the soft tissue structures and potential intracranial involvement. Both techniques are essential for the imperative surgical treatment.

Chronic alcohol intake increases the severity of pancreatitis induced by acute alcohol administration, hyperlipidemia and pancreatic duct obstruction in rats.

BACKGROUND: The mechanism of alcoholic pancreatitis is still unknown. It is of special interest why only about 5% of all alcoholics develop an episode of pancreatitis. We evaluated the role of long-term alcohol intake in the pathogenesis of alcoholic pancreatitis in rats. METHODS: To evaluate the effect of long-term alcohol intake, rats were fed either a Lieber-DeCarli control diet (CD) or a Lieber-DeCarli alcohol diet (AD) for 6 weeks. Then, rats were infused over 2 h with either Ringer's solution (CO) or ethanol (E). In additional animals, alcoholic pancreatitis was induced by ethanol combined with hyperlipidemia and temporary pancreatic duct obstruction (EFO). Controls received Ringer's solution combined with hyperlipidemia and temporary pancreatic duct obstruction (RFO). Intravital microscopy (pancreatic perfusion and leukocyte adhesion), alcohol concentrations, amylase, lipase, cholesterine and triglyceride levels in plasma, myeloperoxidase activity and histology were evaluated at different time intervals. RESULTS: In those animals which received the Lieber-DeCarli control diet, capillary perfusion was reduced in the E group and further reduced in the EFO group as compared to the controls (CO, RFO; p < 0.01). Leukocyte adhesion was significantly increased in rats receiving E (p < 0.01), and was further increased in the combination group EFO (p < 0.01). EFO induced histologically evident acute pancreatitis. The additional administration of a long-term alcohol diet further increased microcirculatory disturbances and pancreatic injury significantly (EFO-AD > EFO-CD). CONCLUSIONS: This study shows that alcoholic pancreatitis is induced by the combination of ethanol and individual cofactors. Chronic alcohol abuse intensifies these changes. Therefore, long-term alcohol intake seems to be a major factor in the pathogenesis of alcoholic pancreatitis.