[The use of minimally invasive instrumental spinal surgical technique in lumbar diseases of degenerative or traumatic origin]. / Minimálisan invazív, instrumentált gerincsebészeti technika alkalmazása degeneratív vagy traumás eredetu ágyéki betegségekben.

Paradigm change has recently taken place in spine surgery with the application of minimally invasive techniques. Minimally invasive techniques have several advantages over the open traditional techniques: less blood loss, preservation of spine muscle integrity, shorter hospitalization, early mobilization, reduced pain levels, lower risk of infection. The presented cases cover following lumbar pathologies: segmental spinal instability, LV-SI grade II. spondylolisthesis, degenerative spondylolisthesis, spine trauma. Unilateral or bilateral mini-open technique was employed in the degenerative cases, depending on symptoms and signes. If unilateral symptoms--pathology was identified, screws and rod were implanted percutaneously on the side contralateral to the pathology. The segmental fusion between vertebral bodies was always assured by a cage and autologous bone. The presented trauma case involved combined AO type A2 and B fractures. The anterior column was strengthened with vertebral body stents filled with bone cement, the posterior column was fixed with a percutaneously implanted screw rod system. Insertion of stents in the collapsed vertebra significantly increased the vertebral body height and also improved the stability of the spine. Minimally invasive spine surgery techniques appear more advantageous over the traditional open spine surgery that necessitates for large midline approaches.

[Preoperative embolisation of spinal metastases]. / A spinális metasztázisok preoperatív embolizációja.

In the management of spinal metastases bringing about neurological symptoms and signs, palliative surgical treatment plays an important role. The goals of surgery are preservation of neurological function especially that of the mobility, pain relief and local tumor control. Many of spinal metastases are hypervascularised, accordingly, preoperative embolisation offers logically improvement in technical realisation of surgery by means of reduction of intraoperative profuse bleeding. To prove this working hypothesis a retrospective analysis was performed. Results of preoperative transarterial embolisation of hypervascularised spinal tumours were worked up from 2000 to 2012. By means of 2 case presentations - to our knowledge, first in the Hungarian literature - the techniques of transarterial spinal embolisation of spinal metastases are described. Indications, complications and effect on intraoperative bleeding events of the embolisation procedure in these oncological cases are presented on the basis of literature search and of our own experience. The case analyses, based mainly on qualitative retrospective data, support the notion that histologically known spinal hypervascularised metastases or those found to be hypervascularised by MRI can be treated effectively by means of preoperative superselective embolisation without major risks of morbidity or mortality.

[Fractionated conformal stereotactic irradiation of recurrent sacral tumour. Case report and first description of the method in Hungary]. / Recidív sacrumdaganat frakcionált, konformális sztereotaxiás sugárkezelése. Esetismertetés és a módszer elsõ hazai leírása.

Non-invasive procedures completing traditional surgical treatment play an increasing role in the management of central nervous system malignancies. Conformal stereotactic irradiation (radiosurgery) has become a routine method in intracranial malignancies. However, application of this modality in tumours of the spinal cord and spinal column is much more difficult to perform. It is because extracranial organs can be only inaccurately fixed, and radio-sensitivity of the spinal cord and risks of radionecrosis with ensuing paraplegia are high. A recurrent sacrum chordoma treated by means of this modality - first reported in Hungary - has been chosen for case presentation as the criteria for radiotherapy such as high dose to target volume, minimal dose to neighbouring structures highly sensitive to radiation are best met in these tumours by means of conformal stereotactic radiotherapy. On the basis of further 13 extracranial cases treated with this method one can conclude that high precision stereotactic conformal radiotherapy offers up-grade to traditional radiotherapy despite the fact that it is a time-consuming procedure. The oncological efficiency, the reduced risks of side effects and the improved quality of life due to this treatment modality compensate duly for the increased labour input.

Comparison of CT characteristics of extravertebral cement leakages after vertebroplasty performed by different navigation and injection techniques.

OBJECTIVE: This study was intended to assess the results of post-operative CT scans in three groups of patients following percutaneous vertebroplasty (VP) using different navigation and injection methods, in an attempt to explain the radiological characteristics of extravertebral cement leakage with relation to needle placement and focused on the ventral epidural accumulation of bone cement. Furthermore, we have suggested a morphological (and functional) classification of the types of cement leakage. METHODS: Between July 2001 and February 2005, 123 percutaneous VP procedures were performed during 75 sessions in 65 patients for treatment of painful osteoporotic vertebral body compression fractures. These included:- Group I: 28 patients, 33 sessions; 50 right sided unilateral VP under fluoroscopic control with central position of the tip of the needle within the bone marrow. Group II: 27 patients, 28 sessions; 50 bilateral VP under fluoroscopic control with separate cement injections into both "hemivertebrae". Group III: 14 patients, 14 sessions; 23 bilateral VP navigated by frameless stereotaxy (neuronavigation). Needles were positioned strictly into the lateral thirds of the vertebral bodies. Leakages were classified as epidural, foraminal, intradiscal, venous paravertebral, compact extravertebral on the post-operative CT scans, and their frequency was compared in relation to the navigation method and the position of the tip of the needle. RESULTS: Group I: extravertebral cement was detected in 23 patients (82%), and in 35 (70%) of the 50 vertebrae treated (ventral epidural: 23 vertebrae = 46%; intradiscal: 12 vertebrae = 24%; venous paravertebral: 8 vertebrae = 16%; intraforaminal: 7 vertebrae = 14%; and compact extravertebral: 3 vertebrae = 6%). Group II: extravertebral cement was detected in 20 patients (74%), and in 38 (76%) of the 50 vertebrae treated (ventral epidural: 12 vertebrae = 24%; intradiscal: 12 vertebrae = 24%; venous paravertebral: 9 vertebrae = 18%; and foraminal: 1 vertebra = 2%). Group III: extravertebral cement could be detected in 10 patients (71%), and in 10 (43%) of the 23 vertebrae treated (ventral epidural: 3 vertebrae = 13%; intradiscal: 8 vertebrae = 34%; venous paravertebral: 4 vertebrae = 17%). CONCLUSION: The incidence of epidural accumulation of bone cement may be concluded to be closely correlated with the position of the tip of the needle. Centrally injected bone cement may easily invade into the basivertebral system, and the material can then be transferred via these veins toward the ventral epidural space, and result in canal compromise and/or compression of the neural elements. The results of statistical analysis (Chi-square test) revealed that injection of bone cement into the lateral third of the vertebral body significantly decreases the extent of ventral epidural leakage. Therefore, a strictly lateral injection is advised, when the tip of the needle is placed into the lateral third of the vertebral body. Frameless stereotaxy navigation improves achievement of accurate needle placement and decreases the frequency of ventral epidural leakage. It is a safe and very accurate method for positioning of the injecting needles.

[Application of vertebroplasty, neuronavigation and kyphoplasty in the treatment of multiplex osteoporotic vertebral fractures--case report]. / Vertebroplastica, neuronavigáció es kyphoplastica alkalmazása poroticus eredetu multiplex kompressziós csigolyatörések kezelésében.

Vertebroplasty is a image-guided therapeutic procedure, consisting of an injection of acrylic cement through a bone biopsy needle into a vertebral body. Main indication for vertebroplasty is painful vertebral body compression fracture due to osteoporosis. The procedure is an efficient mean with high success in pain release and prevention of further collapse of the treated vertebrae; however, the technique does not allow to realign the spine. Kyphoplasty was designed to address the kyphotic deformity. It involves the percutaneous placement of an inflatable bone tamp into a vertebral body (VB). Restoration of VB height and kyphosis correction is achieved by inflation of the tamp with contrast material liquid. After deflation a cavity is created that eases the cement application. The most modern way of guidance in spinal surgery is neuronavigation--the use of frameless stereotaxy. The system reformats patient-specific CT images acquired prior surgery, performs image fusion with intraoperative plain X-ray. Before the operation, the surgeon may create surgical plan and simulate advancement of a virtual instrument along one or more surgical trajectories. During surgery, the system tracks the position of specialized surgical instruments. All three modalities mentioned above have been applied in the treatment of our patient suffered from multiple osteoporotic vertebral body compression fractures. Using kyphoplasty an almost total VB height restoration could be achieved. The pain relief was more than 50% after both operation.

[Percutaneous transpedicular acrylate vertebroplasty for the treatment of lumbar vertebral hemangioma--case report]. / Percutan-transpedicularis akrilát vertebroplastica lumbalis csigolyatest-haemangioma kezelésére--esetismertetés.

The authors present the management of a patient suffering from lumbar vertebral hemangioma. Percutaneous transpedicular acrylate vertebroplasty was performed. This method has widely been used for the treatment of pathological vertebral bodies of different aetiology. A brief review of the literature of previous and current methods is presented. A detailed discussion is given why vertebroplasty was used in contrast to the radiological investigation where the patient's hemangioma proved to be a non-aggressive type. According to the authors' knowledge this is the first Hungarian publication of acrylate vertebroplasty for the treatment of vertebral hemangioma.

[Vertebroplasty: a percutaneous procedure for the treatment of diseased vertebral bodies of various etiologies]. / Különbözó etiológiájú csigolyatest-folyamatok percutan kezelési lehetósége: a vertebroplastica.

Percutaneous vertebroplasty is a radiologically guided invasive technique consisting of the injection of surgical cement into the diseased vertebral body. The procedure results in immediate pain relief and strengthening of the bone due to the polymerization process of the filling material hardening the vertebral body and preventing further collapse. This method is suitable for the treatment of osteoporotic vertebral fractures and of osteolytic vertebral body metastases without neurological signs, in multiple appearance as well. Authors present technical details of the procedure performed by bi-directional fluoroscopy and combined CT-fluoroscopy control as well as short-term experience obtained by treatment of 17 patients.

[Molecular genetic background of developmental bony malformations at the craniocervical junction and cervical spine]. / A nyaki gerinc és a craniocervicalis átmenet csontos-fúziós fejlódési rendellenességeinek molekuláris genetikai háttere.

In this review a new interpretation of the origin of bony developmental malformations affecting the craniocervical junction and the cervical spine is presented based on recent advances in the understanding of embryonic development of the spine and its molecular genetic control. Radiographs, CT and MRI scans or CT myelograms of patients with Klippel-Feil syndrome were used for demonstration. Detailed clinical and radiological analysis of these patients was published earlier [David KM, Stevens JM, Thorogood P, Crockard HA. The dysmorphic cervical spine in Klippel-Feil syndrome: interpretations from developmental biology. Neurosurg Focus 1999;6(6):1.]. Homeotic transformation due to mutations or disturbed expression of Hox genes is a possible mechanism responsible for Cl assimilation. Notochordal defects and/or signalling problems, that result in reduced or impaired Pax-1 gene expression, may underlie vertebral fusions. This, together with asymmetrical distribution of paraxial mesoderm cells and a possible lack of communication across the embryonic mid-line, could cause the asymmetrical fusion patterns. The wide and flattened shape of the fused vertebral bodies, their resemblance to the embryonic cartilaginous vertebrae and the process of progressive bony fusion with age suggest that the fusions occur before or, at the latest, during chondrification of vertebrae. The authors suggest that the aforementioned mechanisms are likely to be, at least in part, responsible for the origin of the bony developmental malformations affecting the craniocervical junction and the cervical spine.