Pulsed Laser-induced Liquid Jet System for Treatment of Sellar and Parasellar Tumors: Safety Evaluation

Trimming of sheep spinal cord by waterjet; an experimental study

The spinal cord is a structure of nervous tissue that primarily transmits nerve signals from the motor cortex to the body and from the afferent fibers of the sensory neurons to the sensory cortex. It is enveloped by three layers of meninges. Covering provides a supportive framework for the cerebral and cranial vasculature and protects the central nervous system (CNS) from mechanical damage. Surgical operation in the vicinity of the spinal cord is complicated and risky because it exposes it to probably irreversible damage. To reduce the risk of these operations, attempts have been made to remove the tumor using safer methods like waterjet operation. In these methods, the waterjet and spinal cord interaction are inevitable. To secure interaction of operation, a standard development of waterjet criteria is necessary. In this study, a system of waterjet is designed to perform sheep spinal cord as a tissue with a good resemblance to the human spinal cord. Effects of interaction between waterjet and sheep spinal cord are investigated to define a safe operation threshold. The impact of the liquid density of waterjet on failure criteria of spinal cord surgery is also investigated. Results show that meninges are stiff enough to protect the sheep spinal cord from rupture for pressures up to 8 bar; however internal spinal cord tissue cannot be guaranteed any damage. Three essential parameters represent the spinal cord meninges and spinal cord deformation during the tests. These parameters lead us to provide standard criteria for damage prevention of the spinal cord.

Specialised Surgical Instruments for Endoscopic and Endoscope-Assisted Neurosurgery: A Systematic Review of Safety, Efficacy and Usability

While there have been great strides in endoscopic and endoscope-assisted neurosurgical approaches, particularly in the treatment of deep-sited brain and skull base tumours, the greatest technical barrier to their adoption has been the availability of suitable surgical instruments. This systematic review seeks to identify specialised instruments for these approaches and evaluate their safety, efficacy and usability. Conducted in accordance with the PRISMA guidelines, Medline, Embase, CENTRAL, SCOPUS and Web of Science were searched. Original research studies that reported the use of specialised mechanical instruments that manipulate tissue in human patients, cadavers or surgical models were included. The results identified 50 specialised instruments over 62 studies. Objective measures of safety were reported in 32 out of 62 studies, and 20 reported objective measures of efficacy. Instruments were broadly safe and effective with one instrument malfunction noted. Measures of usability were reported in 15 studies, with seven reporting on ergonomics and eight on the instruments learning curve. Instruments with reports on usability were generally considered to be ergonomic, though learning curve was often considered a disadvantage. Comparisons to standard instruments were made in eight studies and were generally favourable. While there are many specialised instruments for endoscopic and endoscope-assisted neurosurgery available, the evidence for their safety, efficacy and usability is limited with non-standardised reporting and few comparative studies to standard instruments. Future innovation should be tailored to unmet clinical needs, and evaluation guided by structured development processes.