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1.
Chirurg ; 70(7): 789-94, 1999 Jul.
Article in German | MEDLINE | ID: mdl-10448587

ABSTRACT

A patient with cervical myelopathy caused by marked degenerative alterations of the cervical spinal column at the level of cervical vertebrae 3/4 and relative spinal canal stenosis in the area of cervical vertebrae 5-7 was treated in the department of neurosurgery because of progressive myatrophy and paresis of muscles innervated from cervical nerves 5-7. The operation was performed with vertebrectomy of cervical vertebra 6, implantation of a Harms titanium cage with autograft and a plate and spongy bone screw fixation system. There exists an unusual--and not often publicized--complication during this surgical procedure in the area of the cervical spine, namely penetrating injury of the vertebral artery caused by the treatment with a plate and spongy bone screw fixation system. We describe such an injury of the left vertebral artery. The vertebral artery was intraoperatively embolized using mechanical embolization coils.


Subject(s)
Intraoperative Complications/diagnosis , Intraoperative Complications/therapy , Vertebral Artery/injuries , Bone Plates/adverse effects , Bone Screws/adverse effects , Cervical Vertebrae/blood supply , Cervical Vertebrae/surgery , Humans , Male , Prosthesis Implantation/adverse effects , Prosthesis Implantation/methods , Spinal Stenosis/surgery , Transplantation, Autologous/adverse effects , Transplantation, Autologous/methods
2.
J Magn Reson Imaging ; 8(1): 188-96, 1998.
Article in English | MEDLINE | ID: mdl-9500279

ABSTRACT

The temperature-dependent water proton frequency shift was investigated for temperature monitoring of interstitial thermal coagulation. A procedure for on-line temperature calculation was developed, and errors due to temperature-dependent susceptibility were investigated by finite element analysis and reference measurements. The temperature coefficient of magnetic susceptibility and proton chemical shift were determined for brain tissue and other substances. With the proposed procedure, the location of isotherms could be well visualized during laser-induced interstitial coagulation in vitro and in vivo. Systematic errors caused by magnetic susceptibility changes with temperature depend strongly on the characteristics of the heat source and can exceed susceptibility effects caused by physiologic tissue changes. For the laser applicators discussed here, however, a first order compensation for this effect was found to be satisfactory, because it reduces the absolute error to the range of +/- 1 degrees C. The proposed method represents a very promising approach for monitoring of the interstitial thermal coagulation.


Subject(s)
Electrocoagulation , Hyperthermia, Induced , Magnetic Resonance Imaging/methods , Adipose Tissue/pathology , Adult , Animals , Brain/pathology , Brain Neoplasms/therapy , Computer Simulation , Female , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Spectroscopy/methods , Swine
3.
Biomed Tech (Berl) ; 42(4): 93-6, 1997 Apr.
Article in German | MEDLINE | ID: mdl-9235116

ABSTRACT

The aim of the present study was to investigate, using laser Doppler (LD) flowmetry, the phases immediately prior to and following experimental, neurosurgical laser therapy in animals. Two statistical models obtained on the basis of discriminant analysis are described. These models should enable the user to classify the sets of parameters calculated from the LD signals. With both models which contain 3 and 5 parameters, respectively. 100% discrimination of the two phases was attained. The usefulness of the models could be validated by results obtained with other models.


Subject(s)
Cerebral Cortex/blood supply , Hyperthermia, Induced/instrumentation , Laser-Doppler Flowmetry/instrumentation , Magnetic Resonance Imaging/instrumentation , Signal Processing, Computer-Assisted/instrumentation , Animals , Microcirculation/physiopathology , Monitoring, Intraoperative/instrumentation , Swine
5.
Surg Neurol ; 38(6): 407-10, 1992 Dec.
Article in English | MEDLINE | ID: mdl-1298105

ABSTRACT

Childhood intervertebral disk calcification is a rare clinical entity and usually has a benign course, generally undergoing spontaneous resolution. However, rapid neurologic deterioration due to herniation, found in both of our cases of calcified cervical intervertebral disks, required urgent anterior discectomy and fusion, resulting in excellent recovery.


Subject(s)
Cervical Vertebrae/surgery , Intervertebral Disc Displacement/surgery , Adolescent , Calcinosis/complications , Calcinosis/diagnostic imaging , Cervical Vertebrae/diagnostic imaging , Child , Female , Humans , Intervertebral Disc Displacement/diagnostic imaging , Intervertebral Disc Displacement/etiology , Radiography , Spinal Fusion
6.
J Clin Laser Med Surg ; 10(5): 355-61, 1992 Oct.
Article in English | MEDLINE | ID: mdl-10147968

ABSTRACT

This paper presents the experimental and clinical results of interstitial 1.06 Nd:YAG laser thermotherapy (ILTT) for brain tumors under real-time monitoring by magnetic resonance imaging. The authors chose a laser heat source for interstitial thermotherapy of brain tumors for several important reasons: (1) Laser heat delivery is less complicated and more controlled; (2) laser effects on tissue can be tested, monitored, and controlled by MRI. A 1.064 nm Nd:YAG laser and a specially designed laser optic fiber (ILTT) were used in C.W. mode this study. The laser was used at 4 W at a C.W. mode pulse and total exposure duration was 10 minutes (total energy was 2400 joules). Temperature distribution was determined with a microprocessor-based thermometer and by the levels of the signal intensity under MRI. The relationship between the temperature and MRI signal intensity allowed exploration of the possibility of using MRI as a noninvasive temperature monitoring method. Two patients with glioblastoma and one patient with a brain metastasis were treated with this modality. The results and indications are presented and discussed.


Subject(s)
Brain Neoplasms/radiotherapy , Hyperthermia, Induced/methods , Laser Therapy , Evaluation Studies as Topic , Humans , Hyperthermia, Induced/instrumentation , Magnetic Resonance Imaging
7.
Spine (Phila Pa 1976) ; 17(8): 949-56, 1992 Aug.
Article in English | MEDLINE | ID: mdl-1387977

ABSTRACT

The authors present a new advance in the treatment of herniated disc disease using percutaneous Nd:YAG laser to vaporize a small portion of nucleus pulposus, thereby decompressing the disc. In vitro and in vivo animal data are presented. Three hundred seventy-seven magnetic resonance imaging or computed tomography scan-documented, herniated, nonsequestered lumbar intervertebral discs with corresponding clinical findings in 333 patients were so treated in an outpatient setting. The longest follow-up was 62 months, with a mean of 26 months. According to the Macnab criteria, there was a good to fair response in 261 patients (78.4%), and a poor response in 72 (21.6%); 166 patients experienced relief of pain during the procedure. One-third of repeat magnetic resonance imaging scans at 4-6 months postlaser treatment showed modest to moderate decrease of disc herniation.


Subject(s)
Intervertebral Disc Displacement/surgery , Laser Therapy/methods , Adult , Aged , Aged, 80 and over , Animals , Back Pain/etiology , Back Pain/surgery , Dogs , Female , Humans , Intervertebral Disc Displacement/complications , Intervertebral Disc Displacement/diagnostic imaging , Magnetic Resonance Imaging , Male , Middle Aged , Pain Measurement , Radiography
8.
J Clin Laser Med Surg ; 9(1): 49-57, 1991 Feb.
Article in English | MEDLINE | ID: mdl-10149444

ABSTRACT

We embarked on a project to determine the feasibility of treating carotid artery stenosis with the laser and the clinical results of recanalizing peripheral arteries as a by-product of these studies. In addition, we present a 4-year follow-up of nearly 300 percutaneous disk denaturations in sciatic pain patients. Both methods minimize traditional surgical procedures.


Subject(s)
Arteriosclerosis/surgery , Carotid Artery Diseases/surgery , Intervertebral Disc Displacement/surgery , Laser Therapy/methods , Evaluation Studies as Topic , Feasibility Studies , Femoral Artery/surgery , Follow-Up Studies , Humans , Laser Therapy/instrumentation , Popliteal Artery/surgery
10.
Acta Neurochir (Wien) ; 109(3-4): 133-9, 1991.
Article in English | MEDLINE | ID: mdl-1858531

ABSTRACT

Experimental brain lesions were created by Nd:YAG laser (wave length 1.06 microns) irradiation on the cerebral cortex of anaesthesized adult cats with 20 Watts impacts of 0.5, 1.0, 2.5, and 5.0 seconds exposure time through cranial windows. Histological changes, disruption of the blood-brain barrier (Evans blue extravasation) and pial vessel reaction (large vessels more than 100 microns and vessels smaller than 100 microns) were studied under constant PaCO2, blood pH, and mean arterial pressure. Histological changes of the lesions consisted of a zone of dense coagulation, a pale zone of homogeneous coagulation and an oedematous zone. Evans blue extravasation was uniformly seen extending from the histologically changed area into the surrounding tissue in all experiments. Pial arteries in the area with morphological changes showed pronounced dilatation (100.0 +/- 7.2%) and one third of these arteries were closed by thrombi. Pial arteries in the area of Evans blue extravasation but outside of histological changes also dilated (large arteries 60 +/- 4.1%, small arteries 77 +/- 5.9%). Pial arteries outside of the Evans blue extravasation were affected transiently and only in a very small zone: Within a distance of 200 microns from the Evans blue extravasation, large arteries initially dilated by 41 +/- 8.3%; small arteries dilated within 400 microns (42 +/- 3.7%). Within 4 minutes after irradiation arterial dilatation was again significantly reduced (p less than 0.01). It is concluded that no important vascular changes occur beyond the zones of histologically altered brain tissue.


Subject(s)
Cerebral Arteries/injuries , Cerebral Cortex/injuries , Laser Therapy/adverse effects , Animals , Blood Pressure/physiology , Blood-Brain Barrier/physiology , Cats , Cerebral Arteries/physiopathology , Cerebral Veins/pathology , Cerebral Veins/physiopathology , Evans Blue , Female , Male , Vasodilation/physiology
11.
Article in English | MEDLINE | ID: mdl-1792974

ABSTRACT

Our goal was always to reduce the risks of anaesthesia and surgery to a minimum. Therefore we introduced the interstitial thermotherapy of central brain tumours. The center of the tumour is calculated with the help of computer tomography, then we reach the target stereotactically. The last step includes the insertion of a Nd:YAG laser fiber and the denaturation of the tumour under real time magnetic resonance control. The whole procedure is carried out in local anaesthesia. Methods and first clinical results are demonstrated.


Subject(s)
Brain Neoplasms/surgery , Laser Therapy/instrumentation , Stereotaxic Techniques/instrumentation , Adult , Child , Female , Humans , Hyperthermia, Induced/instrumentation , Magnetic Resonance Imaging/instrumentation , Male
12.
No Shinkei Geka ; 17(7): 641-6, 1989 Jul.
Article in Japanese | MEDLINE | ID: mdl-2812265

ABSTRACT

The effect of the laser energy to the cerebral vascular reactivity and the blood brain barrier. A Nd:YAG laser with 20 watt impacts of 0.5, 1.0, 2.5 and 5.0 seconds duration time were irradiated through the cranial window made at the parietal regions of anesthetized adult cats. The disruption of the blood brain barrier was examined by checking the degree of the extravasation of Evans blue dye administrated in the vein. The cortical vessel reactivity was observed through the cranial window and evaluated using an intravital microscope and a videoangiometer. The extravasation of Evans blue dye was seen uniformly extending from the histologically changed area into the surrounding tissue in all experiments. The extent of the extravasation of dye was 1 to 1.5 mm larger than the extent of the histologically changed area produced by laser irradiation. Pial arteries in the area with histological changes dilated markedly and some of them lost their blood stream. Pial arteries in the area of Evans blue extravasation, but outside it histological changes also dilated markedly. Furthermore, pial arteries within a distance of 200 to 400 microns from the edge of the Evans blue extravasation area also dilated moderately. A statistical estimation showed that the degree of dilatation of arteries in the area outside the histological change improved significantly in the time course of five minutes.


Subject(s)
Blood-Brain Barrier/radiation effects , Cerebral Arteries/radiation effects , Lasers/adverse effects , Animals , Brain/pathology , Brain/radiation effects , Cats , Cerebral Arteries/pathology , Cerebral Arteries/physiology , Evans Blue/pharmacokinetics , Vasodilation/radiation effects
13.
Article in German | MEDLINE | ID: mdl-2577564

ABSTRACT

We report on a project to determine the feasibility of treating carotid artery stenosis with the argon laser (1985) and the clinical results of recanalising peripheral arteries. Training for the above-mentioned project showed that sapphire-tipped Nd:YAG laser optical fibers are the proper instruments for recanalisation. New attempts with new catheter material should make the recanalisation of the carotid artery possible in the future.


Subject(s)
Angioplasty, Laser/instrumentation , Arterial Occlusive Diseases/surgery , Ischemia/surgery , Leg/blood supply , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Recurrence
14.
Acta Neurochir (Wien) ; 90(1-2): 1-14, 1988.
Article in English | MEDLINE | ID: mdl-3278501

ABSTRACT

This paper describes an ultrasound-guided, laser-assisted, and TV-controlled endoscopic technique which has been used so far in 133 patients for a variety of intracranial lesions. Following CT or MRI image reconstruction, and a decision on the placement of a 1 cm or a 2 cm burrhole, a 1 cm 5.0 mHz or 7.5 mHz intraoperative ultrasound probe is used to direct the endoscope from the burrhole to the target area. A 22.5 cm long rigid endoscope tube with an outer diameter of 6 mm with an inbuilt suction irrigation system, Neodymium Yag laser with 600 micron Quartz glass-fibre and an inlet for various microinstruments is then introduced. The attachment of a TV camera to the ocular lens allows the operator to control further surgical steps in the target area via the TV screen and thus warrants sterility in the operating field. The technique has been used for evacuation of 77 spontaneous intracerebral haematomas (lobar, putaminal, thalamic), 8 traumatic intracerebral haematomas, 13 ventricular haematomas, 8 cerebellar haematomas and 1 brainstem haematoma. Total or subtotal evacuation was achieved in 33% of intracerebral haematomas, removal of more than 50% of the clot in 55%. Twenty-four brain tumours (12 ventricular, 12 cystic cerebral or cerebellar tumours) were operated on for biopsy, evacuation of cyst, resection or removal of the cyst wall and/or laser irradiation of solid tumour or the inner cyst wall of cystic tumours. The complication rate probably related to surgery was 1.6%, morbidity 1.6%, mortality 0%. This high-tec endoscopic technique with its minimal surgical trauma and short operation time can be recommended as a low-risk alternative to conventional neurosurgical techniques.


Subject(s)
Endoscopy/methods , Neurosurgery/methods , Adult , Aged , Brain Diseases/pathology , Brain Diseases/surgery , Brain Neoplasms/diagnostic imaging , Brain Neoplasms/pathology , Brain Neoplasms/surgery , Cerebral Hemorrhage/diagnostic imaging , Cerebral Hemorrhage/pathology , Cerebral Hemorrhage/surgery , Cerebral Ventricle Neoplasms/diagnostic imaging , Cerebral Ventricle Neoplasms/pathology , Cerebral Ventricle Neoplasms/surgery , Child, Preschool , Cysts/pathology , Cysts/surgery , Endoscopes , Female , Humans , Male , Neurosurgery/instrumentation , Tomography, X-Ray Computed , Ultrasonography
15.
Rofo ; 147(2): 119-23, 1987 Aug.
Article in German | MEDLINE | ID: mdl-2819962

ABSTRACT

The first in-vivo trials were carried out on arteries of the extremities which have a straight course and short segmental occlusions. Initial experience indicates that obstructions up to 20 cm in length can be overcome by burning through plaques and thrombotic material by means of a neodymium-YAG-laser and then recanalised. By using a 2.2 mm spherical sapphire, one obtains a channel of 2.5 mm diameter through the obstruction. Subsequently dilatation with a balloon catheter is necessary. Laser angioplasty does not complicate the procedure significantly as far as the patient is concerned, since both the laser catheter and the balloon can be introduced through the same No. 7 F introducer into the femoral artery. Peripheral emboli could not be demonstrated angiographically, nor were they clinically manifest. On the basis of present experience, it seems that recanalisation of occlusions in arteries in the extremities, using a neodymium-YAG-laser focused by a synthetic sapphire, is a feasible alternative to conventional mechanical recanalisation.


Subject(s)
Arterial Occlusive Diseases/surgery , Laser Therapy/methods , Arterial Occlusive Diseases/pathology , Arteriosclerosis/pathology , Arteriosclerosis/surgery , Cadaver , Evaluation Studies as Topic , Femoral Artery/pathology , Femoral Artery/surgery , Humans , In Vitro Techniques , Laser Therapy/instrumentation
16.
Wien Klin Wochenschr ; 99(11): 393-7, 1987 May 29.
Article in German | MEDLINE | ID: mdl-3039746

ABSTRACT

In glioblastoma multiforme and high-grade astrocytomas the following procedure has been implemented to try and prevent recurrence: after extirpation of the tumour its bed is lined with metal powder and the patient's head is exposed to a high-frequency magnetic field every 4 weeks. As a result the temperature is raised by induction to +45 degrees C at the boundary between metal and brain tissue. This ought to be sufficient to prevent tumour recurrence. Varied results were achieved using this technique in 103 patients.


Subject(s)
Brain Neoplasms/therapy , Glioblastoma/therapy , Hyperthermia, Induced , Brain Neoplasms/surgery , Combined Modality Therapy , Follow-Up Studies , Humans , Hyperthermia, Induced/instrumentation
17.
Lasers Surg Med ; 7(2): 180-3, 1987.
Article in English | MEDLINE | ID: mdl-3613809

ABSTRACT

Of a total of 580 patients suffering from expanding spinal disease, 15 cases of intramedullary lesions were dealt with by the use of the CO2 laser. Sharp cutting and precisely controlled depth effect are the advantages that make the CO2 laser very useful for surgery within the spinal cord. In tumors of tough consistency the neoplastic tissue is usually sharply demarcated, in which case the CO2 laser is used for dissection along this borderline, at an output energy of 15-20 W, infocus, continuous wave (CW). In tumors of soft consistency, characterized by a more-or-less diffuse zone of invasion--eg, glioblastomas-vaporization [20 W, out-of-focus, CW] and removal by ultrasound-microsuction is recommended. This procedure should advance layer by layer until normal looking tissue is reached. In this way intramedullary tumors may be removed with minimal side effects. The postoperative course involves less pain and less edematous reaction, and the rehabilitation time is shortened compared with conventional surgical treatment. In benign neoplasms long-term results are good; malignant cases require additional x-ray treatment and chemotherapy.


Subject(s)
Laser Therapy , Spinal Cord Neoplasms/surgery , Humans , Magnetic Resonance Spectroscopy , Postoperative Complications , Spinal Cord/pathology , Spinal Cord Neoplasms/diagnosis , Spinal Cord Neoplasms/pathology
18.
Dtsch Med Wochenschr ; 111(16): 607-10, 1986 Apr 18.
Article in German | MEDLINE | ID: mdl-3956403

ABSTRACT

Argon laser irradiation via a transfemorally introduced catheter successfully vapourized both fresh thrombi and stenosing plaques in the carotid artery of seven cadavers and two patients. Fresh thrombi were recanalized throughout their length, while the arteriosclerotic plaques were partially reduced. No particles larger than 7 micron were demonstrated in the eluant flushing fluid, indicating that peripheral emboli need not be feared with this technique.


Subject(s)
Arteriosclerosis/surgery , Carotid Artery Thrombosis/surgery , Laser Therapy , Arteriosclerosis/pathology , Cadaver , Catheterization/methods , Femoral Artery , Humans
19.
Article in English | MEDLINE | ID: mdl-3867254

ABSTRACT

The introduction of lasers in neurosurgery in 1976 can be considered as a major contribution to gaining access to "untouchable" areas of the brain. This immaterial instrument provides for precise cutting at low penetration depth in surrounding tissues and may carbonize, and thus remove, layers not to be touched because of their highly sensitive vicinity. From a total of 794 patients experiencing the advantages of laser surgery (1976-1984), a series of 12 children with lower brainstem tumors is presented. Intraoperative instability of vital functions was absent throughout, leaving the patients without deterioration of their initial neurological condition. Given appropriate handling and adequate experience, the laser is a singularly helpful surgical tool for gaining access to areas hitherto barred to surgery.


Subject(s)
Brain Neoplasms/surgery , Laser Therapy , Medulla Oblongata , Pons , Adolescent , Child , Child, Preschool , Humans , Infant , Infant, Newborn , Microsurgery
20.
Lasers Surg Med ; 5(5): 499-506, 1985.
Article in English | MEDLINE | ID: mdl-4068883

ABSTRACT

Eight years of experience with the CO2 laser and 4 years experience with the neodymium laser in 737 neurosurgical cases are presented with absolute and relative indications and observations. Future developments are discussed.


Subject(s)
Brain Diseases/surgery , Brain Neoplasms/surgery , Laser Therapy , Spinal Cord Neoplasms/surgery , Humans , Intracranial Arteriovenous Malformations/surgery , Meningeal Neoplasms/surgery , Meningioma/surgery
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