Lasers In Neurosurgery Research Articles

SURG-43. APPLICATIONS AND RESTRICTION OF 980NM DIODE LASER FOR BRAIN TUMOR MICROSURGERY - A PIONEER CASE SERIES AND A CRITICAL REVIEW

Abstract BACKGROUND Quality of life is essential for oncological patients. There are several tools that help surgery become more precise with less morbidity. Diode laser can cut and coagulate through thermal effect being helpful during surgery. It is a precise and useful technology that improves outcomes in neurooncology. OBJECTIVES To describe a pioneer case series of oncological use of diode laser and main applications of several types of laser in neurooncology. METHODS Detailed description of a pioneer case series of oncological patients that undergone to neurosurgical laser assisted procedures. An interventional longitudinal prospective study was conducted. Patients that had as mainly hypothesis the diagnosis of glioma or meningioma were selected. Also it was performed an extensive literature review about lasers in neurosurgery with special focus in diode laser. RESULTS There was not any paper describing the use of diode laser in neurooncology. The 980nm diode laser was used in 15 patients. The device had an easy handling. Decreased intra-operative time for hemostasis, lesser blood loss requiring less blood transfusion was observed. No post-operative complications occurred. CONCLUSIONS Diode laser is a useful tool for brain tumor surgery especially concerning hemostasis, providing decreased blood loss with lesser intra-operative duration. Surgical site coagulation is more effective causing less damage to adjacent structures specially in gliomas near eloquent regions. We consider this technique as a suitable adjuvant therapy for brain tumor surgeries providing an excellent hemostasis and helping cutting and vaporize lesion. This device makes surgery safer and decrease oncological morbidity.

Safety and Efficacy of 980nm Diode Laser for Brain Tumor Microsurgery—A Pioneer Case Series

Quality of life is essential for oncologic patients. Several tools are available to improve microsurgery and reduce morbidity. Diode laser is a precise and useful technology for microsurgery. The goal of this pioneer case series is to describe the oncologic use of the 980nm diode laser and the qualitative variables analyzed. Besides, review the current literature about lasers in neurosurgery. A longitudinal prospective study described patients with meningioma or glioma submitted to neurosurgical laser-assisted procedures. Also, we performed a review in medical databases using the terms "diode laser" and "neurosurgery." No paper described the use of a diode laser in neurooncology. The 980nm diode laser was used in 15 patients. The device is thin, silent, and easy to handle. Excellent hemostasis was observed, especially in skull base meningiomas. Also, it was easy and fast to delimit tumor from normal brain tissue without damage to surrounding parenchyma. No postoperative complications occurred. The diode laser is a useful tool for brain tumor surgery, particularly concerning hemostasis. Surgical site coagulation is effective without damage to adjacent structures, especially in gliomas near eloquent regions. We consider this technique a suitable adjuvant resource for brain tumor surgeries to provide an excellent hemostasis and help cut and vaporize a lesion.

Stereotaxic laser brain surgery with 1940-nm Tm:fiber laser: An in vivo study.

With exciting developments in fiber laser technology, studies investigating the use of lasers in neurosurgery have been increasing in the recent years. Fiber lasers are advantageous in many ways; first of all they are compact and they provide a more comfortable environment in the operating room due to feasibility of coupling laser light to different cross-sectioned fibers. Thulium fiber (Tm:fiber) lasers have been under investigation for medical applications since 2005 due to their spectral proximity to the water absorption peak. The primary aim of this study is to investigate the thermal effects of the 1940-nm Tm:fiber laser on subcortical tissue and to examine the effects of laser parameters on laser-induced lesions. Secondarily, it is also aimed to reveal the importance of temperature monitoring during laser surgeries by investigating the effects of temperature change on the characteristics of laser-induced lesions. Stereotaxic laser brain surgery was performed on 20 male Wistar rats, in order to investigate the thermal effects of Tm:fiber laser. During surgeries temperature changes in the subcortical tissue were observed with a t-type thermocouple for which a holder was designed to accomplish a 1 mm distance between the fiber tip and thermocouple tip. Histological examinations were performed on cresyl fast violet (CFV) stained slices under light microscopy. Photothermal effects of Tm:fiber laser on subcortical tissue were investigated in terms of ablated (removal of tissue), coagulated and edematous areas with a blinded micrograph evaluation. Relations between laser parameters, ablation efficiencies and rates of temperature changes were determined. Pearson's correlation coefficients between rates of temperature changes and ablation efficiencies, total laser damage and edematous area were calculated. No significant adverse effects were observed during surgeries. Histological examinations revealed localized ablation surrounded by coagulation areas as well as edema. Ablation efficiencies ranged from 20% to 50% with changing laser parameters. The correlation coefficient between rates of temperature change and ablation efficiencies, total laser damage and edematous area were rather high. In this study we show that Tm:fiber lasers seem to be useful tools in brain surgeries especially to vaporize and coagulate the tissue. It is also shown that temperature monitoring during laser surgery is very crucial and gives information about laser-induced lesion. Another take home message from this study is rather than the temperature increase, the rate of temperature change is more important. We found that if the temperature is changing in a short time interval, the extent of thermal damage can be minimized. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.

Stereotactic laser thermocoagulation in epilepsy surgery

In common with other stereotactic procedures, stereotactic laser thermocoagulation (SLT) promises gentle destruction of pathological tissue, which might become especially relevant for epilepsy surgery in the future. Compared to standard resection, no large craniotomy is necessary, cortical damage during access to deep-seated lesions can be avoided and interventions close to eloquent brain areas become possible. We describe the history and rationale of laser neurosurgery as well as the two available SLT systems (Visualase® and NeuroBlate®; CE marks pending). Both systems are coupled with magnetic resonance imaging (MRI) and MR thermometry, thereby increasing patient safety. We report the published clinical experiences with SLT in epilepsy surgery (altogether approximately 200 cases) with respect to complications, brain structural alterations, seizure outcome, neuropsychological findings and treatment costs. The rate of seizure-free patients seems to be slightly lower than for resection surgery. Due to the inadequate quality of studies, the neuropsychological superiority of SLT has not yet been unambiguously demonstrated.

Lasers in Neurosurgery

Lasers in Neurosurgery

Large-scale in vivo femtosecond laser neurosurgery screen reveals small-molecule enhancer of regeneration

Discovery of molecular mechanisms and chemical compounds that enhance neuronal regeneration can lead to development of therapeutics to combat nervous system injuries and neurodegenerative diseases. By combining high-throughput microfluidics and femtosecond laser microsurgery, we demonstrate for the first time large-scale in vivo screens for identification of compounds that affect neurite regeneration. We performed thousands of microsurgeries at single-axon precision in the nematode Caenorhabditis elegans at a rate of 20 seconds per animal. Following surgeries, we exposed the animals to a hand-curated library of approximately one hundred small molecules and identified chemicals that significantly alter neurite regeneration. In particular, we found that the PKC kinase inhibitor staurosporine strongly modulates regeneration in a concentration- and neuronal type-specific manner. Two structurally unrelated PKC inhibitors produce similar effects. We further show that regeneration is significantly enhanced by the PKC activator prostratin.

High throughput laser neurosurgery screening of Caenorhabditis elegans

High throughput laser neurosurgery screening of Caenorhabditis elegans

Development and Evaluation of a Registration Methodology for Information-Guided Precision Robotic Laser Neurosurgery System

Development and Evaluation of a Registration Methodology for Information-Guided Precision Robotic Laser Neurosurgery System

Aura of technology and the cutting edge: a history of lasers in neurosurgery

In this historical review the authors examine the important developments that have led to the availability of laser energy to neurosurgeons as a unique and sometimes invaluable tool. They review the physical science behind the function of lasers, as well as how and when various lasers based on different lasing mediums were discovered. They also follow the close association between advances in laser technology and their application in biomedicine, from early laboratory experiments to the first clinical experiences. Because opinions on the appropriate role of lasers in neurosurgery vary widely, the historical basis for some of these views is explored. Initial enthusiasm for a technology that appears to have innate advantages for safe resections has often given way to the strict limitations and demands of the neurosurgical operating theater. However, numerous creative solutions to improve laser delivery, power, safety, and ergonomics demonstrate the important role that technological advances in related scientific fields continue to offer neurosurgery. Benefiting from the most recent developments in materials science, current CO(2) laser delivery systems provide a useful addition to the neurosurgical armamentarium when applied in the correct circumstances and reflect the important historical advances that come about from the interplay between neurosurgery and technology.

Computer-guidedlaser probe for ablation of brain tumours with ultrashort laserpulses

A computer-guided laser probe has been developed for the application of ultrashort-pulsed lasers in neurosurgery. It is part of a novel operation concept for the treatment of deep-seated brain tumours. The system combines the positioning accuracy of stereotactic or neuronavigated instruments with the precise and therefore gentle characteristics of surgical lasers. The probe has an outer diameter of 5.5 mm and is directly inserted into the target volume. By a synchronized movement of three coaxial tubes, which guide the embedded optics, the laser radiation is focused at any time onto the current tissue surface. Since every single laser pulse has only a small effective volume of about 8 × 105 µm3, the application of a large number of succeeding pulses can be adapted to required geometries. Tissue fragments are removed from the growing operation cavity by continuous irrigation and suction through the laser probe. Blood vessels are detected by a confocal laser-scanning microscope, which is integrated into the probe, and can be closed by an additional coagulating laser. In this paper, the design and technical properties of the laser probe as well as its use in ablation and coagulation experiments are presented. A description of the overall operation system is given.

Hemostatic properties of the free-electron laser

We have investigated the hemostatic properties of the free-electron laser (FEL) and compared these properties to the most commonly used commercial lasers in neurosurgery, CO 2 and Nd:YAG, using an acute canine model. Arterial and venous vessels, of varying diameters from 0.1 to 1.0 mm, were divided with all three lasers. Analysis of five wavelengths of the FEL (3.0, 4.5, 6.1, 6.45, and 7.7 microns) resulted in bleeding without evidence of significant coagulation, regardless of whether the vessel was an artery or vein. Hemorrhage from vessels less than 0.4 mm diameter was subsequently easily controlled with Gelfoam® (topical hemostatic agent) alone, whereas larger vessels required bipolar electrocautery. No significant charring, or contraction of the surrounding parenchyma was noted with any of the wavelengths chosen from FEL source. The CO 2 laser, in continuous mode, easily coagulated vessels with diameters of 4 mm and less, while larger vessels displayed significant bleeding requiring bipolar electrocautery for control. Tissue charring was noted with application of the CO 2 laser. In super pulse mode, the CO 2 laser exhibited similar properties, including significant charring of the surrounding parenchyma. The Nd:YAG coagulated all vessels tested up to 1.4 mm, which was the largest diameter cortical artery found, however this laser displayed significant and extensive contraction and retraction of the surrounding parenchyma. In conclusion, the FEL appears to be a poor hemostatic agent. Our results did not show any benefit of the FEL over current conventional means of achieving hemostasis. However, control of hemorrhage was easily achieved with currently used methods of hemostasis, namely Gelfoam® or bipolar electrocuatery. Although only cortical vessels in dogs were tested, we feel this data can be applied to all animals, including humans, and the peripheral, as well as central, vasculature, as our data on the CO 2 and Nd:YAG appear to closely support previous reports of hemostasis of these two lasers obtained in other models.

Study into penetration speed during laser cutting of brain tissues

The applications of CO2 continuous-wave lasers in neurosurgery have become important in recent years. Theoretical considerations of laser applicability in medicine are subsequently confirmed experimentally. To obtain precision operation in the laser cutting process, further theoretical developments and experimental studies need to be conducted. Consequently, in the present study, the heat transfer mechanism taking place during laser-tissue interaction is introduced using Fourier-theory. The results obtained from the theoretical model are compared with the experimental results. In connection with this, an experiment is designed to measure the penetration speed during the laser cutting process. The measurement is carried out using an optical method. It is found that both results for the penetration speed obtained from the theory and experiment are in a good agreement.

脳神経外科領域に於けるレーザー手術の現況と脊髄内視鏡について

脳神経外科領域に於けるレーザー手術の現況と脊髄内視鏡について

Experimental and clinical standards, and evolution of lasers in neurosurgery.

From initial experiments of ruby, argon and CO2 lasers on the nervous system so far, dramatic progress was made in delivery systems technology as well as in knowledge of laser-tissue interaction effects and hazards through various animal experiments and clinical experience. Most surgical effects of laser light on neural tissue and the central nervous system (CNS) are thermal lesions. Haemostasis, cutting and vaporization depend on laser emission parameters--wavelength, fluence and mode--and on the exposed tissues optical and thermal properties--water and haemoglobin content, thermal conductivity and specific heat. CO2 and Nd-YAG lasers have today a large place in the neurosurgical armamentarium, while new laser sources such as high power diode lasers will have one in the near future. Current applications of these lasers derive from their respective characteristics, and include CNS tumour and vascular malformation surgery, and stereotactic neurosurgery. Intracranial, spinal cord and intra-orbital meningiomas are the best lesions for laser use for haemostasis, dissection and tissue vaporization. Resection of acoustic neuromas, pituitary tumours, spinal cord neuromas, intracerebral gliomas and metastases may also benefit from lasers as accurate, haemostatic, non-contact instruments which reduce surgical trauma to the brain and eloquent structures such as brain stem and cranial nerves. Coagulative lasers (1.06 microns and 1.32 microns Nd-YAG, argon, or diode laser) will find an application for arteriovenous malformations and cavernomas. Any fiberoptic-guided laser will find a use during stereotactic neurosurgical procedures, including image-guided resection of tumours and vascular malformations and endoscopic tumour resection and cysts or entry into a ventricle. Besides these routine applications of lasers, laser interstitial thermotherapy (LITT) and photodynamic therapy (PDT) of brain tumours are still in the experimental stage. The choice of a laser in a neurosurgical operating room implies an evaluation of the laser use (applications, frequency), of the available budget and costs--including purchase, maintenance and staff training--, and material that will be necessary: unit, peripherals, safety devices and measures, training programme. Future applications of lasers in neurosurgery will come from technological advances and refined experimental applications. The availability of new wavelength, tunable, small sized and "smart" laser units, will enlarge the thermal and non-thermal interactions between laser energy and neural tissue leading to new surgical applications. Tissue photo-ablation, photohynamic therapy using second generation of photosensitizers, updated thermotherapy protocols, are current trends for further use of lasers in neurosurgery.

脳神経外科領域に於ける顕微鏡下・内視鏡下レーザー手術の現状

Present situation of laser neurosurgery using operating microscope and endoscope are discussed. The lasers which we have mainly used are the CO2 laser and KTP laser. The CO2 laser is very useful to remove hard tissues, even calcified one, through narrow surgical field, especially in cases of deep-seated highly vascular tumors. A case of teratoma in the third ventricle and a case of deep-seated cavernous angioma in the left posterior temporal lobe which were removed by the CO2 laser are presented in this paper. The dural protector which we developed enables the operator to perform safe and complete removal of ossified posterior longitudinal ligament. Vaporizing capability of the KTP laser is far stronger than that of the YAG laser in the open-air surgical field. One of the advantages of the KTP laser is that it can be applied through fine optical fiber, which enable endoscopic use through CSF. And also the handpiece of the KTP laser can be designed very thin and light because this laser beam can be transmitted through optical fiber, which is very important in microsurgery. Recently we have started endoscopic examination of spinal lesions. This new technique revealed some interesting findings, such as rapid to and fro movement of CSF in the area where the subarachnoid space is narrowed, which is impossible to observe without this method. Hyper-vascularization of cauda equina caused by spinal tumor, thickning and adhesion of arachnoid were clearly observed by this sytem. However, development of special bipolar coagulator which can be applied through the working channel is indispensable prior to endoscopic interventions of spinal lesions, although the KTP laser is already applicable.

Lasers in neurosurgery

Lasers have been used in neurosurgery for the past 25 years, undergoing modifications to suit the specific needs of this medical discipline. The present report reviews the current use of lasers in neurosurgical practice and examines the pros and cons of lasers in specific neurosurgical applications. In spite of their advantages, laser use is still not widespread in neurosurgery. One reason is the continued lack of complete control over real-time laser interactions with neural tissue. A greater acceptance and use of lasers by neurosurgeons will depend upon automated control over defined specific parameters for laser applications based upon the type of tissue, the desired effect on tissue, and application to the clinical situation without loss of precision and a lot of expense. This will require the integration of newer lasers, computers, robotics, stereotaxy, and concepts of minimally invasive surgery into the routine management of neurosurgical problems.

Lasers in Neurosurgery

Lasers in Neurosurgery

LASERS IN NEUROSURGERY

Australian and New Zealand Journal of SurgeryVolume 63, Issue 3 p. 244-244 LASERS IN NEUROSURGERY Brian North, Brian North Department ofNeurosurgery Royal Adelaide Hospital AdelaideSearch for more papers by this author Brian North, Brian North Department ofNeurosurgery Royal Adelaide Hospital AdelaideSearch for more papers by this author First published: March 1993 https://doi.org/10.1111/j.1445-2197.1993.tb00533.xAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume63, Issue3March 1993Pages 244-244 RelatedInformation

Present and future applications of lasers in neurosurgery.

The applications of laser in both adults and pediatric neurosurgery are being steadily refined today. For many routine tumor removals, contemporary lasers do not add to ultrasonic aspiration or suction resection. However, there are some tumors in which one CO2 laser is invaluable; brain stem astrocytomas, skull base tumors, and intraspinal tumors are examples. Similarly, in resections of spinal lipomas they are useful to vaporize lipomas from the roots. Laser welding of vessels is technically possible but has generally not been useful. Perhaps the most exciting application is a combination of laser energy transfer with stereotactic technology. The MRI can be used to visualize structural changes in cerebral tissue. We have used this technology in 40 rats with gliomas and have been able to demonstrate destruction.

Lasers in neurosurgery: a historical overview.

This contribution to the history of laser applications to neurosurgical patients gives the background against which the subsequent developments took place. It covers the important facts regarding the theoretical formulations that led to the invention of the world's first laser in 1960. This was a pulsed ruby laser, which proved lacking in desirable surgical procedures, and at high powers was shown to be damaging to vital organs, such as the brain. It could be lethal to small animals. These very early tests of laser tissue and organ interaction included studies on protein in solution, cultured cells, brain, spinal cord and their surrounding tissues, and transplantable melanomas, as well as ependymoblastomas in mice. Fortunately, the continuous wave CO 2 laser came along in 1967 to replace both the pulsed ruby and neodymium-in-glass lasers. The CO 2 laser was quickly seen to possess surgical properties, namely, vaporization, cutting, hemostasis, and sterilization, without additional damage at a distance or remotely in time. Research studies on normal and pathologic tissues in and around the brain and spinal cord quickly and dramatically showed the potential for benefit to animal and human patients with experimental and naturally occurring neoplasms, burns, and decubitus ulcers. Lasers in neurosurgery are used largely for benign and malignant brain and spinal neoplasms. For benign tumors, debulking of tumor mass, and ablation of unwanted neoplasm without damaging adjacent, vital, functioning neural tissue, the laser adds another therapeutic adjunct and will, at times, aid in complete tumor removal. For malignant vascular growths, the laser will aid greatly in the safest possible excision with maximum hemostasis. Studies around the world, ongoing or planned, will surely extend the uses of lasers for neurosurgery into vascular, infectious, and reconstructive fields, particularly with the proliferation of laser instruments that exploit additional wavelengths into the larger infrared levels and even the shorter ultraviolet region. Experimental and, to some extent, clinical applications are testing the value of Nd:YAG, holmium:YAG, and erbium:YAG lasers in various surgical fields.