[Effects of Tranexamic Acid on Perioperative Blood Loss and Wound Hematoma Development in Lumbar Spine Surgery: a Prospective Randomized Study]

PURPOSE OF THE STUDY Tranexamic acid as a haemostatic agent is commonly used in multiple medical branches. Over the last decade, there has been a steep rise in the number of studies evaluating its effect, i.e. blood loss reduction in specific surgical procedures. The aim of our study was to evaluate the effect of tranexamic acid on reducing intraoperative blood loss, postoperative blood loss into the drain, total blood loss, transfusion requirements, and development of symptomatic wound hematoma in conventional single-level lumbar decompression and stabilization. MATERIAL AND METHODS The study included patients who had undergone a traditional open lumbar spine surgery in the form of single-level decompression and stabilisation. The patients were randomized into two groups. The study group received a 15 mg/kg dose of tranexamic acid intravenously during the induction of anaesthesia and then again 6 hours later. No tranexamic acid was administered to the control group. In all patients, intraoperative blood loss, postoperative blood loss into the drain, and therefore also total blood loss, transfusion requirements and potential development of a symptomatic postoperative wound hematoma requiring surgical evacuation were recorded. The data of the two groups were compared. RESULTS The cohort includes 162 patients, 81 in the study group and the same number in the control group. In the intraoperative blood loss assessment, no statistically significant difference between the two groups was observed; 430 (190-910) mL vs. 435 (200-900) mL. In case of post-operative drain blood loss, a statistically significantly lower volume was reported after the tranexamic acid administration; 405 (180-750) mL vs. 490 (210-820) mL. When evaluating the total blood loss, a statistically significant difference was also confirmed, namely in favour of the tranexamic acid; 860 (470-1410) mL vs. 910 (500- 1420) mL. The reduction of total blood loss did not result in a difference in the number of administered transfusions; transfusions were given to 4 patients in each group. A postoperative wound hematoma requiring surgical evacuation developed in 1 patient in the group with the tranexamic acid and in 4 patients in the control group, but the difference was not statistically significant with respect to the insufficient group size. No patient in our study experienced complications associated with tranexamic acid application. DISCUSSION The beneficial effect of tranexamic acid on reducing blood loss in lumbar spine surgeries has already been confirmed by numerous meta-analyses. The question remains in what types of procedures, at what dose and route of administration its effect is significant. To date, most of the studies have explored its effect in multi-level decompressions and stabilizations. Raksakietisak et al., for instance, report significant reduction in total blood loss from 900 (160, 4150) mL to 600 (200, 4750) mL following an intravenous injection of 2 bolus doses of 15 mg/kg tranexamic acid. In less extensive spinal surgeries, the effect of tranexamic acid may not be that distinct. In our study of single-level decompressions and stabilizations, no reduction in the actual intraoperative bleeding was confirmed at the given dosage. Its effect was seen only in the postoperative period in a significant reduction of blood loss into the drain, thus also in the total blood loss, although the difference between 910 (500, 1420) mL and 860 (470, 1410) mL was not that significant. CONCLUSIONS By intravenous application of tranexamic acid in 2 bolus doses in single-level decompression and stabilization of the lumbar spine a statistically significant reduction in postoperative blood loss into the drain and also total blood loss was confirmed. The reduction in the actual intraoperative blood loss was not statistically significant. No difference was observed in the number of administered transfusions. Following the tranexamic acid administration, a lower number of postoperative symptomatic wound hematomas was recorded, but the difference was not statistically significant. Key words: tranexamic acid, spinal surgeries, blood loss, postoperative hematoma.

[Coccygodynia: Case Reports and Literature]

Coccygodynia, or tailbone pain, is the most common in women after trauma (complicated childbirth, fall). This pain can be treated conservatively (by using analgesics, local injections, physiotherapy) or by surgical coccygectomy. In the presented article, a set of five female patients is evaluated, in whom, after the failing conservative therapy, coccygectomy was indicated for persistent coccygodynia. In all female patients, improvement of their clinical condition and alleviation of pain were reported. Coccygectomy has its place in the management of coccygodynia and in correctly chosen patients significant pain reduction can be expected. Key words: coccygodynia, coccyx, coccygectomy, trauma.

[Minimally Invasive Sacroiliac Joint Stabilization]

PURPOSE OF THE STUDY Sacroiliac joint dysfunction is defined as a permanent chronic pain originating from the sacroiliac joint, limiting the patient's daily activities. The purpose of this study was to evaluate the effectiveness of the minimally invasive sacroiliac joint stabilization by triangular titanium implants in patients with sacroiliac joint dysfunction. MATERIAL AND METHODS The prospective study evaluated the patients who had underwent a minimally invasive sacroiliac joint stabilization for sacroiliac joint dysfunction with the use of iFuse® implants. The surgery was performed solely under fluoroscopic guidance or together with the use of O-arm O2® mobile imaging system. The clinical condition, the Visual Analogue Scale preoperatively and one year postoperatively, previous surgeries in the lumbar spine region, the use of O-arm and occurrence of complications were recorded. The minimum follow-up period was 1 year. RESULTS The group was composed of 20 patients, of whom 4 men and 16 women. The mean age was 48.9 years. The surgeries covered 21 sacroiliac joints. Improvement of the clinical condition was reported in 17 cases (81.0%), no relief was observed in 4 cases (19%). The mean VAS score was 6.1 points preoperatively and decreased to 2.9 points postoperatively (p=0.0001). CONCLUSIONS The minimally invasive sacroiliac joint stabilization should be reserved for patients experiencing an intractable pain originating from the sacroiliac joint, in whom all non-operative therapy failed. Key words: minimally invasive sacroiliac joint stabilization, sacroiliac joint dysfunction, O-arm.

32nd International Austrian Winter Symposium : Zell am See, the Netherlands. 20-23 January 2016

A1 68Ga-PSMA PET/CT in staging and restaging of Prostate Cancer Patients: comparative study with 18F-Choline PET/CT

W Langsteger, A Rezaee, W Loidl, HS Geinitz, F Fitz, M Steinmair, G Broinger, L Pallwien-Prettner, M Beheshti

A2 F18 Choline PET – CT: an accurate diagnostic tool for the detection of parathyroid adenoma?

L Imamovic, M Beheshti, G Rendl, D Hackl, O Tsybrovsky, M Steinmair, K Emmanuel, F Moinfar, C Pirich, W Langsteger

A3 [18F]Fluoro-DOPA-PET/CT in the primary diagnosis of medullary thyroid carcinoma

A Bytyqi, G Karanikas, M Mayerhöfer, O Koperek, B Niederle, M Hartenbach

A4 Variations of clinical PET/MR operations: An international survey on the clinical utilization of PET/MRI

T Beyer, K Herrmann, J Czernin

A5 Standard Dixon-based attenuation correction in combined PET/MRI: Reproducibility and the possibility of Lean body mass estimation

I Rausch, P Rust, MD DiFranco, M Lassen, A Stadlbauer, ME Mayerhöfer, M Hartenbach, M Hacker, T Beyer

A6 High resolution digital FDG PET/MRI imaging for assessment of ACL graft viability

K Binzel, R Magnussen, W Wei, MU Knopp, DC Flanigan, C Kaeding, MV Knopp

A7 Using pre-existing hematotoxicity as predictor for severe side effects and number of treatment cycles of Xofigo therapy

A Leisser, M Nejabat, M Hartenbach, G Kramer, M Krainer, M Hacker, A Haug

A8 QDOSE – comprehensive software solution for internal dose assessment

Wencke Lehnert, Karl Schmidt, Sharok Kimiaei, Marcus Bronzel, Andreas Kluge

A9 Clinical impact of Time-of-Flight on next-generation digital PET imaging of Yttrium-90 radioactivity following liver radioembolization

CL Wright, K Binzel, J Zhang, Evan Wuthrick, Piotr Maniawski, MV Knopp

A10 Snakes in patients! Lessons learned from programming active contours for automated organ segmentation

M Blaickner, E Rados, A Huber, M Dulovits, H Kulkarni, S Wiessalla, C Schuchardt, RP Baum, B Knäusl, D Georg

A11 Influence of a genetic polymorphism on brain uptake of the dual ABCB1/ABCG2 substrate [11C]tariquidar

M Bauer, B Wulkersdorfer, W Wadsak, C Philippe, H Haslacher, M Zeitlinger, O Langer

A12 Outcome prediction of temporal lobe epilepsy surgery from P-glycoprotein activity. Pooled analysis of (R)-[11C]-verapamil PET data from two European centres

M Bauer, M Feldmann, R Karch, W Wadsak, M Zeitlinger, MJ Koepp, M-C Asselin, E Pataraia, O Langer

A13 In-vitro and in-vivo characterization of [18F]FE@SNAP and derivatives for the visualization of the melanin concentrating hormone receptor 1

M Zeilinger, C Philippe, M Dumanic, F Pichler, J Pilz, M Hacker, W Wadsak, M Mitterhauser

A14 Reducing time in quality control leads to higher specific radioactivity of short-lived radiotracers

L Nics, B Steiner, M Hacker, M Mitterhauser, W Wadsak

A15 In vitro 11C-erlotinib binding experiments in cancer cell lines with epidermal growth factor receptor mutations

A Traxl, Thomas Wanek, Kushtrim Kryeziu, Severin Mairinger, Johann Stanek, Walter Berger, Claudia Kuntner, Oliver Langer

A16 7-[11C]methyl-6-bromopurine, a PET tracer to measure brain Mrp1 function: radiosynthesis and first PET evaluation in mice

S Mairinger, T Wanek, A Traxl, M Krohn, J Stanek, T Filip, M Sauberer, C Kuntner, J Pahnke, O Langer

A17 18F labeled azidoglucose derivatives as “click” agents for pretargeted PET imaging

D Svatunek, C Denk, M Wilkovitsch, T Wanek, T Filip, C Kuntner-Hannes, J Fröhlich, H Mikula

A18 Bioorthogonal tools for PET imaging: development of radiolabeled 1,2,4,5-Tetrazines

C Denk, D Svatunek, T Wanek, S Mairinger, J Stanek, T Filip, J Fröhlich, H Mikula, C Kuntner-Hannes

A19 Preclinical evaluation of [18F]FE@SUPPY- a new PET-tracer for oncology

T Balber, J Singer, J Fazekas, C Rami-Mark, N Berroterán-Infante, E Jensen-Jarolim, W Wadsak, M Hacker, H Viernstein, M Mitterhauser

A20 Investigation of Small [18F]-Fluoroalkylazides for Rapid Radiolabeling and In Vivo Click Chemistry

C Denk, D Svatunek, B Sohr, H Mikula, J Fröhlich, T Wanek, C Kuntner-Hannes, T Filip

A21 Microfluidic 68Ga-radiolabeling of PSMA-HBED-CC using a flow-through reactor

S Pfaff, C Philippe, M Mitterhauser, M Hartenbach, M Hacker, W Wadsak

A22 Influence of 24-nor-ursodeoxycholic acid on hepatic disposition of [18F]ciprofloxacin measured with positron emission tomography

T Wanek, E Halilbasic, M Visentin, S Mairinger, B Stieger, C Kuntner, M Trauner, O Langer

A23 Automated 18F-flumazenil production using chemically resistant disposable cassettes

P Lam, M Aistleitner, R Eichinger, C Artner

A24 Similarities and differences in the synthesis and quality control of 177Lu-DOTA-TATE, 177Lu -HA-DOTA-TATE and 177Lu-DOTA-PSMA (PSMA-617)

H Eidherr, C Vraka, A Haug, M Mitterhauser, L Nics, M Hartenbach, M Hacker, W Wadsak

A25 68Ga- and 177Lu-labelling of PSMA-617

H Kvaternik, R Müller, D Hausberger, C Zink, RM Aigner

A26 Radiolabelling of liposomes with 67Ga and biodistribution studies after administration by an aerosol inhalation system

U Cossío, M Asensio, A Montes, S Akhtar, Y te Welscher, R van Nostrum, V Gómez-Vallejo, J Llop

A27 Fully automated quantification of DaTscan SPECT: Integration of age and gender differences

F VandeVyver, T Barclay, N Lippens, M Troch

A28 Lesion-to-background ratio in co-registered 18F-FET PET/MR imaging – is it a valuable tool to differentiate between low grade and high grade brain tumor?

L Hehenwarter, B Egger, J Holzmannhofer, M Rodrigues-Radischat, C Pirich

A29 [11C]-methionine PET in gliomas - a retrospective data analysis of 166 patients

N Pötsch, I Rausch, D Wilhelm, M Weber, J Furtner, G Karanikas, A Wöhrer, M Mitterhauser, M Hacker, T Traub-Weidinger

A30 18F-Fluorocholine versus 18F-Fluorodeoxyglucose for PET/CT imaging in patients with relapsed or progressive multiple myeloma: a pilot study

T Cassou-Mounat, S Balogova, V Nataf, M Calzada, V Huchet, K Kerrou, J-Y Devaux, M Mohty, L Garderet, J-N Talbot

A31 Prognostic benefit of additional SPECT/CT in sentinel lymph node mapping of breast cancer patients

S Stanzel, G Pregartner, T Schwarz, V Bjelic-Radisic, B Liegl-Atzwanger, R Aigner

A32 Evaluation of diagnostic value of TOF-18F-FDG PET/CT in patients with suspected pancreatic cancer

S Stanzel, F Quehenberger, RM Aigner

A33 New quantification method for diagnosis of primary hyperpatahyroidism lesions and differential diagnosis vs thyropid nodular disease in dynamic scintigraphy

A Koljević Marković, Milica Janković, V Miler Jerković, M Paskaš, G Pupić, R Džodić, D Popović

A34 A rare case of diffuse pancreatic involvement in patient with merkel cell carcinoma detected by 18F-FDG

MC Fornito, D Familiari

A35 TSH-stimulated 18F-FDG PET/CT in the diagnosis of recurrent/metastatic radioiodine-negative differentiated thyroid carcinomas in patients with various thyroglobuline levels

P Koranda, H Polzerová, I Metelková, L Henzlová, R Formánek, E Buriánková, M Kamínek

A36 Breast Dose from lactation following I131 treatment

WH Thomson, C Lewis

A37 A new concept for performing SeHCAT studies with the gamma camera

WH Thomson, J O’Brien, G James, A Notghi

A38 Whole body F-18-FDG-PET and tuberculosis: sensitivity compared to x-ray-CT

H Huber, I Stelzmüller, R Wunn, M Mandl, F Fellner, B Lamprecht, M Gabriel

A39 Emerging role 18F-FDG PET-CT in the diagnosis and follow-up of the infection in heartware ventricular assist system (HVAD)

MC Fornito, G Leonardi

A40 Validation of Poisson resampling software

WH Thomson, J O’Brien, G James

A41 Protection of PET nuclear medicine personnel: problems in satisfying dose limit requirements

J Hudzietzová, J Sabol, M Fülöp

[Influence of Cervical Spondylotic Spinal Cord Compression on Cerebral Cortical Adaptation. Radiological Study]

PURPOSE OF THE STUDY

The aim of the study was to measure the sensorimotor brain adaptation activity, shown on functional magnetic resonance images (fMRI), in relation to the degree and extent of spinal cord compression or cervical spondylotic myelopathy (CSM) detected by cervical spine MRI.

MATERIAL AND METHODS

Twenty-one patients (average age, 57 years; 9 men and 12 women) with anterior cervical cord compression detected on cervical MRI scans were included. On the images, the degree of spinal canal stenosis, the spinal cord compression based on the antero-posterior diameter of the spinal canal and on transverse areas of the cervical spinal cord and cervical spinal canal, and changes in spinal cord signal intensity were identified. Clinical examination included neurological status, Japanese Orthopaedic Association (JOA) score, Neck Disability Index (NDI) and pain intensity assessment using the Visual Analogue Scale (VAS). Electrophysiological tests involving motor evoked and sensory evoked potential (MEP and SEP) recording were conducted and, using fMRI, brain activity during movement of both arms was measured. Based on the transverse spinal cord area of above or below 70 mm2, the patients were placed into two subgroups. According to changes in spinal cord signal intensity, the patients were included into three subgroups with normal findings, incipient myelopathy and advanced myelopathy, respectively. Surgery was carried out from the anterior approach and involved cervical disc replacement. All examinations were performed again at 6 months after surgery. Pre- and post-operative results were compared within each set of subgroups and statistically evaluated.

RESULTS

The average pre-operative values were found to increase post-operatively as follows: from 6.4 mm to 8.9 mm (by 39%) for the antero-posterior diameter of the spinal canal; from 129.3 mm2 to 162.8 mm2 (by 26%) for the transverse area of the spinal canal; from 72.6 mm2 to 87.4 mm2 (by 20%) for the transverse spinal cord area; and from 16.3 to 17.4 for the JOA score. The average NDI decreased from 37.9 to 23.7 and the average VAS fell from 6.4 to 1.5. All patients with the change of spinal cord signal that indicated advanced myelopathy also had relevant pathological findings on MEP/SEP examination and this was statistically significant. There was no significant difference in fMRI scans between the two subgroups established on the basis of transverse spinal cord area measurements. In the patients grouped by a change in spinal cord signals, the pre-operative fMRI showed a significantly higher brain activation volume in the subgroup with advanced myelopathy, as compared with the two other subgroups. Surgery resulted in a moderate reduction of the volume of active brain tissue in all three groups. In the patients with advanced myelopathy evaluated in relation to local changes in brain activation, surgery led to a significant decrease in activation volumes in the ipsilateral primary motor cortex and cerebellar hemisphere. There was also a significant increase in activation of the contralateral supplementary motor cortex.

DISCUSSION

It is evident that the brain responds to spinal cord damage by increased activity, but with a certain delay. A slightly altered spinal cord signal intensity, such as in incipient myelopathy, apparently does not result in brain activation. On the other hand, significant changes in signal intensity in advanced myelopathy are related to deterioration of spinal cord function, as shown by MEP and SEP examination results, and an increase in both the volume and intensity of cortical motor activation as a compensation mechanism for myelopathy. CONCLUSIONS Hyperintense spinal cord signals on T2-weighted images correlated with the pathological spinal cord function detected by electrophysiological test in all patients. The transverse spinal cord area (around 70 mm2) showed no significant correlation with either sensory and motor brain adaptations or the results of SEP and MEP testing; therefore, as a criterion for indication to surgery it is of no value. The patients with advanced myelopathy, as detected by spinal cord MRI, had a significantly higher pre-operative cortical motor activation on fMRI than patients with normal findings or those with incipient myelopathy. In addition, the patterns of cortical motor activation altered significantly at 6 months after spinal cord decompression, which was shown by an increase or decrease in activation of the relevant motor cortex areas.

[Effects of spinal cord decompression in patients with cervical spondylotic myelopathy oncortical brain activations]

INTRODUCTION

The aim of this project was to compare and evaluate cortical sensorimotor adaptations as measured by brain fMRI (functional magnetic resonance imaging) in patients before and after surgery for cervical spondylotic myelopathy (CSM), i.e., after spinal cord decompression.

MATERIAL AND METHODS

Study inclusion required evidence of CSM on MRI of the cervical spine, anterior compression of the spinal cord by osteophytes, or disc herniation. We measured the antero-posterior diameter of the spinal canal stenosis before and 3 months after surgery. Surgery was performed at one or two levels from the anterior approach with implantation of radiolucent spacers, without plate fixation. Each participant underwent two fMRI brain examinations, the first one preoperatively and the second one 6 months following surgery. Subjects performed acoustically paced repetitive wrist flexion and extension of each upper extremity according to block design. MRI data were acquired using 1.5 Tesla scanners. Statistical analysis was carried out using the general linear model implemented in FEAT 6.00 (FMRI Expert Analysis Tool), part of the FSL 5.0 package (FMRIB Software Library). The group differences were evaluated using paired t-test and the resulting statistical maps evaluated as Z-score (standardised value of the t-test) were thresholded at a corrected significance level of p <0.05. The study group consisted of 7 patients including 5 female and 2 male patients, with the average age of 55.7 years. Patients with cervical spondylogenous radiculopathy were evaluated as a control group.

RESULTS

The analysis of mean group effects in brain fMRI during flexion and extension of both wrists revealed significant activation in dorsal primary motor cortex contralaterally to the active extremity and in adjacent secondary motor and sensory areas, bilaterally in supplementary motor areas, the anterior cingulum, primary auditory cortex, in the region of the basal ganglia, thalamus and cerebellum. After surgery, the cortical activations and maximum Z-scores decreased in most areas. Analysis of differences between sessions before and after surgery showed a statistically significant activation decrease during movement of both extremities in the right parietal operculum and the posterior temporal lobe. During left wrist movement, there was additional activation decrease in the right superior parietal lobe, the supramarginal gyrus, insular cortex, and the central operculum. In contrast, an activation decrease was detected in the left middle temporal gyrus during right wrist movement.

CONCLUSION

An average difference of anteroposterior cervical spinal canal distance before and after surgery of CSM was 2.67 millimetres, representing a 40% increase; the cross-sectional area of the spinal canal increased by 37% and that of the spinal cord by 36%. Functional MRI of the brain revealed significant activation especially in primary and secondary motor cortex and sensory areas in patients with CSM. After surgical decompression of the spinal cord, cortical activations and maximum Z-score decreased in the majority of areas. We proved decreased cortical activation on functional MRI of the brain after surgery in patients with CSM (evaluated according to MRI of cervical spine), even at an initial stage of the disease.

18F, 11C and 68Ga in small animal PET imaging. Evaluation of partial volume correction methods

AIM

The partial volume effect (PVE) significantly affects quantitative accuracy in PET. In this study we used a micro-hollow sphere phantom filled with 18F, 11C or 68Ga to evaluate different partial volume correction methods (PVC). Additionally, phantom data were applied on rat brain scans to evaluate PVC methods on in vivo datasets.

METHODS

The four spheres (7.81, 6.17, 5.02, 3.90 mm inner diameter) and the background region were filled to give sphere-to-background (sph/bg) activity ratios of 20 : 1, 10 : 1, 5 : 1 and 2 : 1. Two different acquisition and reconstruction protocols and three radionuclides were evaluated using a small animal PET scanner. From the obtained images the recovery coefficients (RC) and contrast recovery coefficients (CRC) for the different sph/bg ratios were calculated. Three methods for PVC were evaluated: a RC based, a CRC based and a volume of interest (VOI) based method. The most suitable PVC methods were applied to in vivo rat brain data.

RESULTS

RCs were shown to be dependent on the radionuclide used, with the highest values for 18F, followed by 11C and 68Ga. The calculated mean CRCs were generally lower than the corresponding mean RCs. Application of the different PVC methods to rat brain data led to a strong increase in time-activity curves for the smallest brain region (entorhinal cortex), whereas the lowest increase was obtained for the largest brain region (cerebellum).

CONCLUSION

This study was able to show the importance and impact of PVE and the limitations of several PVC methods when performing quantitative measurements in small structures.

Using positron emission tomography to study transporter-mediated drug-drug interactions in tissues

Drug disposition is highly regulated by membrane transporters. Some transporter-mediated drug–drug interactions (DDIs) may not manifest themselves in changes in systemic exposure but rather in changes in tissue exposure of drugs. To better assess the impact of transporter-mediated DDIs in tissues, positron emission tomography (PET)—a noninvasive imaging method—plays an increasingly important role. In this article, we provide examples of how PET can be used to assess transporter-mediated DDIs in different organs.

[Surgery for degenerative spondylolisthesis of the lumbar spine using intra-articular fusion. A prospective study]

PURPOSE OF THE STUDY

The aim of the study is to present our surgical method of treating degenerative spondylolisthesis, which includes radical bilateral laminectomy to relieve compression on the spinal cord, transpedicular fixation of the segment and arthrodesis by bilateral intra-articular fusion.

MATERIAL AND METHODS

This surgery was indicated in patients with grade I or grade II of degenerative sponylolisthesis with a 4-mm or more slippage. Our prospectively studied group consisted of 46 patients (17 men, 29 women; average age, 64.2 years; range, 39-84 years). Before surgery and at 1 year after the procedure, the intensity of axial pain and that of radicular pain were each assessed using the visual Analogue Scale (VAS). Difficulty in performing daily living activities was measured by the Oswestry Disability Index (ODI). The surgical procedure included laminectomy, partial medial facetectomy, foraminotomy to relieve pressure on the spinal nerve roots and transpedicular fixation to provide stability. Using a cutter, cartilage was separated off the cortical bone and, in order to facilitate fusion, bone cavities thus produced were filed with corticospongious grafts harvested from the removed vertebral arch with Kerrison forceps. At 1-year follow-up, dynamic X-ray was used to evaluate spine alignment and, on a CT scan, the degree of intra-articular fusion was assessed. Fusion was achieved when bone density measurement showed more than 350 Hounsfield Units (HU). For the measurements, the authors used their own modified method by means of a Region of Interest (ROI) analysis. The clinical and radiographic results were statistically evaluated.

RESULTS

At 1 year after surgery, lumbar flexion-extension bending X-ray films revealed stability of the treated segments in all patients (100%). CT examination showed bone density higher than 350 HU at both joints, i.e., complete bone fusion, also in all 46 patients. The mean post-operative ODI score was significantly lower than its mean pre-operative value (23.6 vs 55.4), which was improvement by 57.4%. The differences in pre- and post-operative VAS scores were also statistically significant. The mean VAS score for low back pain decreased from 7.61 to 1.74, i.e., improvement by 77.1%, and the mean vAS score for radicular pain dropped from 6.98 to 1.24, i.e., improvement by 82.2%. Assessed by Odom's outcome criteria, the results were excellent in 26 patients and very good in 20 patients, and they were not related to age, gender or the spinal level treated. Any complications associated with the operative procedure or wound healing and requiring repeated surgical treatment were not recorded.

DISCUSSION

The surgical technique described here has advantages over other methods in reliable achieving nerve decompression, joint fusion and spinal stability at low costs and short operative time. In addition, it avoids the necessity of harvesting bone from the iliac crest.

CONCLUSIONS

At 1-year follow-up all patients showed better health conditions, with improvement in average scores for the ODI by 57%, for low back pain by 77% and for radicular and claudication pain by 82%. The technique of intra-articular fusion for treatment of degenerative spondylolisthesis resulted in solid bone fusion and spinal stability in all patients.

[Percutaneous interspinous dynamic stabilization (in-space) in patients with degenerative disease of the lumbosacral spine - a prospective study]

INTRODUCTION

Interspinous spacers are supposed to reduce the segmental extension with a decrease in the expansion of yellow ligaments into the spinal canal, thus avoiding the dynamic narrowing of the spinal canal and compression of nerve roots. The aim of this study was to evaluate clinical outcomes and post-operative complications during one year in patients mostly having suffered from spinal stenosis and treated by In-Space interspinous spacer (Synthes, USA).

MATERIAL AND METHODS

A total of 25 patients aged between 25 and 73 (average age 52.6) years, including 18 males and 7 females, with degenerative disease of the lumbosacral spine were indicated for surgery and prospectively followed up. The patients were operated on under general anaesthesia in the prone position, using a minimally invasive lateral percutaneous approach, under fluoroscopic control. The ODI and VAS values as well as X- rays (Range Of Motion and Sagittal angle of the operated segment) 6 and 12 months after the surgery were compared to each other and to those before surgery. The results were statistically analyzed.

RESULTS

The average ODI of the group was 47.2% before surgery and 17.48% 6 months (22.76% 12 months) after surgery, showing a statistically significant improvement by 63% (52% after 12 months). The average VAS of the group was 6.64 points before surgery and 2.96 points 6 months (2.8 points 12 months) after surgery, which showed a statistically significant improvement by 55.4% after 6 months (57.8% after 12 months) when compared to preoperative status. After surgery the lordotic sagittal angle remained in all cases; one year after surgery the angle increased due to the slight sinking of some implants. The extent of segmental motion was minimally changed (6.1° 6 months and 7.24° 12 months after surgery). No serious complications occurred. The effect of interspinous implants proved insufficient in two cases (one year and two years after surgery) and conversion to arthrodesis or decompression was performed.

CONCLUSIONS

1. Percutaneous, minimally invasive insertion of an In-Space interspinous spacer is an effective and safe method of dynamic stabilization not accompanied by any serious complications. 2. ODI improved by 63% 6 months after surgery with a decrease in this effect 12 months after surgery. VAS for axial and radicular pain, as reported by patients, improved on average by 55.4% 6 months and by 57.8% 12 months after surgery. 3. In all cases, the lordotic sagittal angle remained after surgery and the extent of segmental motion from flexion to extension was minimally changed.

[Percutaneous dynamic interspinous stabilisation for the treatment of juxtafacet cysts of the lumbar spine: prospective study]

PURPOSE OF THE STUDY

To present the authors' philosophy on the surgical treatment of juxtafacet cysts of the lumbosacral (LS) spine, with its primary aim of dynamic lumbar stabilisation with an interspinous implant, inserted by a minimally invasive approach, without concurrent exploration of the spinal canal and cyst removal.

MATERIAL AND METHODS

During a 20-month period, ten patients aged between 25 and 70 years (average age, 53.2 years) were indicated for surgical treatment of a juxtafacet cyst by percutaneous insertion of an In-Space interspinous spacer without surgical exploration of the spinal canal. The group comprised six men and four women. At a follow-up of 6 weeks to 18 months, each patient underwent MRI examination of the LS spine and the degree of cyst resorption was assessed. The visual analogue scale (VAS) scores, Oswestry Disability Index (ODI) and range of motion (ROM) values, and a sagittal angle (SA) of the segment treated obtained for the whole group at 3 to 18 months after surgery were compared with the pre-operative va - lues. The surgeon evaluated the effect of surgery on radicular and axial pain.

RESULTS

Complete resorption of the cyst was found in seven patients (70%) and three (30%) showed partial resorption. Complete resolution of radicular symptoms was reported by five patients (50%); five experienced partial relief (50%). Lumbago was relieved completely in three (30%) and partially in seven (70%) patients. The average VAS score was 6.7 points (range, 4-10) pre-operatively and 3.5 (0-8) post-operatively, i.e. it decreased by 3.2 points, which meant an improvement by 48%. The average ODI value was 58.4% (range, 32-80) pre-operatively and 23.9% (0-70) post-operatively, i.e., it decreased by 34.5 percentage points and was an improvement by 59%. The average ROM measures were 5.65 degrees (range, 2°-10°) pre-operatively and 5.55 degrees (0°-19°) post-operatively. The average pre- and post-operative sagittal angles in normal lumbar lordosis were 7.1 degrees (1°-13°) and 6.2 degrees (1°-11°), respectively.

DISCUSSION

The conventional surgical procedure involves cyst extirpation. However, the procedure only relieves nerve root compression but does not remove the cause of juxtafacet cyst development, which is due to facet joint degeneration and instability. This may results in persistent or recurrent clinical symptoms. On the other hand, a reduction of both mobility and loading of the intervertebral joints achieved by implantation of an interspinous spacer is the mechanism allowing for resorption of the cyst and resolution of symptoms.

CONCLUSIONS

1. The original method of treating juxtafacet cysts of the LS spine by an In-Space interspinous spacer, as presented here, was efficient in all patients and resulted in complete, or at least partial, resorption of the cyst. 2. Segmental mobility and spondyloarthritis are the major aetiological factors of juxtafacet cyst development. 3. Dynamic interspinous stabilisation will reduce loading of the intervertebral joints and will thus allow for cyst resorption and clinical symptom resolution. 4. Percutaneous implantation of an "In-Space" interspinous spacer is a minimally invasive method of dynamic stabilisation that means no restrictions in patients' activities and reduces the length of hospital stay.

[Multiple spinal myeloma and its surgical management]

INTRODUCTION AND AIM

The management of spinal multiple myeloma (MM) is a complex process, including causal treatment (i.e. efforts to suppress the tumor clone), as well as supportive therapy, including surgery. The aim of this article is to present retrospective evaluation of surgical indications in patients with MM or solitary spinal plasmocytoma.

MATERIAL

A total of 10 patients (8 males and 2 females) aged from 32 to 74 years (the mean age of 53.3) were included in the study. The enrolment criteria were the following: patients operated for MM or solitary spinal plasmocytoma during the past 7-year period, with the minimum follow up period of 6 months. The procedures were indicated for progressing neurological deficit (Frankel score) and for axial spinal pain (VAS classification), not responding to conservative therapy. The extent of the disease was assessed based on plain x-ray, MRI and whole- body 18F-FDG PET/CT. Paliative vertebroplasty was indicated in patients with no neurological deficit to control pain, paliative laminectomy without stabilization in subjects with partial neurological lesions, with transpedicular fixation in concomitant pathological fractures or kyphotizations. More radical approach, i.e. the procedure included somatectomy, was indicated in patients with solitary plasmocytoma and in procedures on cervical or thoracolumbar regions. Control clinical and MRI examinations were performed at 6 weeks, at 6 months and then at yearly intervals. At the end of the study, the authors evaluated effectivity of the employed surgical procedures, based on all control findings, and the data were compared with prognostic scoring systems in surgery for spinal metastases (Tomita score, Tokuhashi modified score and Bauer score).

RESULTS

No local relapses of the tumor or stabilization failure were detected. The effect of surgery on pain control and on prevention of neurological dysfunction was maintained over the follow up period. The authors concluded that all surgical procedures and their radicality were adequate in all subjects. The agreement between the authors approach (the procedure's radicality) and the Tomita score, the Tokuhashi modified score and the Bauer score were recorded in 50% of patients, 80% of patients and in 50% of patients, respectively.

DISCUSSION

MM is characterized by increased oseteolysis, which is not followed by new bone formation. Despite successful conservative therapy of MM, the bone defects fail to heal, cause spinal pain and may result in spinal instability. These specific MM signs represent the principal factor in the decision- making process concerning indication for surgery. Furthermore, favourable prognosis, with survival times usually exceeding the required expected minimum survival time of 3-6 months, is yet another reason for indication for surgical therapy in patients with spinal MM. Due to advances in chemotherapy and the use of autologic grafts of peripheral stem cells and radiotherapy, the prognosis of patients have significantly improved in last 10 years. The mean survival time has increased from 2.5 years to 4.5 years.

CONCLUSION

1. Prevention or improvement of neurological dysfuction and pain control are the main indication criteria for surgery in MM. 2. Surgery should be considered in MM with osteolytic spinal disorder and because of favourable prognosis of the disease when surgery is used. 3. Surgical procedures, including paliative methods resulted in sufficient control of spinal stability in all the study subjects. 4. Using all scoring systems for spinal metastases could result in indications for unnecessary more radical procedures. However, Tokuhashi score appeared to be the most suitable existing prognostic scoring system.

[Surgery for symptomatic vertebral hemangiomas]

INTRODUCTION AND AIM

Vertebral hemangiomas (VH) are usually asymptomatic and, therefore, are commonly detected as accidental findings on spinal imaging. No treatment is indicated in these cases. Nevertheless, some hemangiomas may clinically manifest as axial pain and neurological deficit and may require surgery or other treatment. The aim of this study was to assess outcomes of surgical management of symptomatic vertebral hemangiomas at two neurosurgical clinics.

MATERIAL AND METHODS

Prospective study of patients with symtomatic vertebral hemangioma managed surgically at Neurosurgical Clinic of Faculty Hospital and Medical Faculty (FN and LF UP) of Palacky University in Olomouc and at Neurosurgical Department of Ostrava-Fifejdy Hospital. Surgery was indicated in patients with confirmed thoracic and lumbar vertebral hemangioma, presenting with axial, eventually with radicular pain and/or neurological deficit, such as myelopathy or radicular lesion. In cases where the only basis for indication for surgery was axial lumbar pain, the procedure included only vertebroplasty (VP) of the vertebral body (Vertecem, Synthes, USA). In cases with neurological dysfunction, posterior decompression using hemilaminectomy with extirpation of hemangioma tissue protruding into the spinal canal, as well as vertebroplasty, was indicated. During the 13-month study period, 7 patients aged from 38 to 80 years (the mean age of 60.3 years) were operated. The subjects included 4 males and 3 females. Follow up examinations were performed during hospitalization, at 6 weeks and at 6 months after the procedure. On the last follow up examination, the patients were asked to assess axial and radicular pain based on the VAS scale, ODI and the surgeons evaluated the degree of myelopathy according to Frankel and JOA classification.

RESULTS

Vertebroplasty had positive impact on the degree of axial and radicular pain in all subjects (seven patients) and combination of VP with decompression resulted in improvement of myelopathic symptoms in all the subjects concerned (three patients). No spinal canal cement leak or embolization during VP was recorded, neither surgical wound healing complications, such as hematoma or infection, were recorded. No surgical revisions were required.

DISCUSSION

The aim of symptomatic vertebral hemangioma therapy include nervous tissue decompression, spinal stabilization and prevention of spontaneous or traumatic epidural bleeding. Nervous tissue decompression using laminectomy or hemilamine- ctomy can be indicated only in patients developing severe paraparesis and may have good outcome. It is advisable to combine decompression with vertebroplasty or balloon kyphoplasty, arterial embolization or intralesional alcohol injection.

CONCLUSION

Vertebroplasty resulted in pain score improvement in all patients with symptomatic vertebral hemangiomas. Combinations of vertebroplasty and decompression had positive impact on myelopathic symptoms in all the patients concerned.

[Treatment of degenerative spondylolisthesis of the lumbosacral spine by decompression and dynamic transpedicular stabilisation]

PURPOSE OF THE STUDY

The aim of the study was to present the effect and advantages of surgical decompression and dynamic transpedicular stabilisation in patients with degenerative spondylolisthesis of the lumbosacral spine.

MATERIAL AND METHODS

This prospective study involved patients undergoing dynamic transpedicular stabilisation using Isolock or Isobar TTL (Scient X, France) systems. Between June 2003 and June 2009, 65 patients were treated and followed-up. They were aged 35 to 75 years (average, 57.17 years), and there were 32 men and 33 women. Follow-up ranged from 1 to 6 years. Based on indications for surgery they fell into two groups. Group 1 included 52 patients with grade I or II degenerative spondylolisthesis or retrolisthesis. Group 2 (control) consisted of 13 patients with degenerative disc disease or failed back surgery syndrome. The disorder had always been manifested by combined axial and radicular symptoms. Treatment included posterior decompression of nerve structures by laminectomy in conjunction with semi-rigid stabilisation, without fusion. Followup clinical (VAS, ODI), neurological and radiographic examinations were carried out at 6 weeks, 6 months and 1 to 6 years after surgery. The VAS and ODI results of both groups were statistically analysed and compared.

RESULTS

During follow-up the ODI values decreased by 54 % (from 58.4 % to 26.8 %) and VAS values by 62 % (from 7.9 to 3.0) as compared with the pre-operative values, and this was statistically significant. When both groups were compared, the VAS values decreased significantly (by 5.61) in Group 1, as compared with Group 2 (decrease by 3.54).

DISCUSSION

In the treatment of pseudospondylolisthesis, the semi-rigid stabilisation with spinal decompression, as presented here, is a convenient alternative to simple decompression without fixation or to various forms of instrumented or non-instrumented arthrodesis. A disadvantage associated with arthrodesis is a higher risk of ASD development; dynamic systems do not allow for reduction of spondylolisthesis and involve a change in sagittal spinal balance, and simple decompression carries the risk of slip progression and recurrent problems.

CONCLUSIONS

The authors demonstrated that decompression combined with semi-rigid stabilisation had a very good effect on the clinical state of patients with degenerative spondylolisthesis (retrolisthesis) at medium-term follow-up. The procedure was less effective in other indications. Semi-rigid stabilisation with Isobar TTL or Isolock systems prevented the progression of anterolisthesis or retrolisthesis; none of the patients experienced instrumentation failure. Neither symptomatic restenosis nor disc herniation was found in the instrumented segment. Semi-rigid stabilisation can, if necessary, be converted to fusion or disc replacement.

[Identification of the lumbosacral nerve plexus during the extreme lateral interbody fusion procedure]

PURPOSE OF THE STUDY

The aim of this clinical observation study was to determine the extent to which muscle relaxation induced by anesthesia must be intra-operatively reversed for a reliable identification, by intra-operative monitoring, of the lumbosacral (LS) nerve roots during extreme lateral interbody fusion (XLIF). MATERAL AND METHODS: General anesthesia (midazolam, propofol, sufentanil, oxygen/air/sevofluran - rocuronium) was administrated to all pa - tients. Train-of-four (TOF) stimulation of the ulnar nerve at 10-second intervals and an electromyographic response of the adductor pollicis muscle were used, and the duration of neuromuscular block was measured by the value of the TOF-ratio. When the level of recovery from neuromuscular block was TOF-count = 2, reversion to normal function was still accelerated by sugammadex administration at a dose of 2 mg.kg-1. Subsequently, it was determined at which level of muscle relaxation subsidence the first responses to LS nerve root stimulation were evident. Intra-operative neurophysiologial monitoring (IOM) with use of the NIM - Neuro® 3.0 device allowed for assessment of a triggered electromyographic reaction (tEMG) of LS roots to stimulation during surgery. The neuromuscular reactions were evaluated in 11 patients, five men and six women. The results were analysed by descriptive statistics and presented as median and interquartile-range values.

RESULTS

In all patients a reliable monitoring of the depth of muscle relaxation was established. The value of supramaximal impulse was 46 mA (38 to 64 mA). The period from rocuronium administration to a spontaneous recovery of the TOF-count = 2 took 33 min (29 to 35 min). Duration from sugammadex administration to a TOF ratio of . 0.70 was 90 seconds (50 to 140) and to a TOF ratio of . 0.90 was 190 seconds (100 to 220 s). A reliable tEMG response of LS nerve roots to electric stimulation at 10 mA intensity was recorded at a TOF ratio of 0.68 (0.56 to 0.77) and at a 5 mA intensity it was reliable at a TOF ratio of 0.86 (0.75 to 0.90).. None of the patients reported radicular symptoms after surgery.

DISCUSSION

From the anatomy of the greater psoas muscle and varied patterns of its LS plexus it is obvious that none of the zones is absolutely safe. In XLIF procedures it is therefore recommended to disect the psoas muscle under both visual and IOM control. Intra-operative checking of the depth of muscle relaxation then will provide information that conditions not affected by rocuronium administration and necessary for the detection of LS roots have been provided.

CONCLUSIONS

1. For a reliable intra-operative identification of LS nerve roots by electric stimulation at a 10 mA intensity it is recommended to achieve the value of TOF ratio equal to at least 0.70. When stimulation at a lower intensity (5 mA) is used, a TOF ratio of . 0.90 is necessary. 2. Administration of sugammadex to reverse an action of the muscle relaxant rocuronium is an effective and quick method to achieve the values required.

[XLIF--a new technique of the lumbar vertebra disc replacement: initial experience]

Extreme lateral interbody fusion (XLIF) is a novel technique for the anterior disc replacement. The aim of this report was description of the surgical technique of XLIF. Based on our experience with first eleven patients we report advantages and drawbacks of this method. Patients who presented with symptomatic degenerative disc disease or failed back surgery syndrome were considered candidates for this surgery. The patient was placed in a true right lateral decubitus position and small (6 cm) left lateral skin incision was performed. Access to the lumbar spine was achieved by approach that passes through the retroperitoneally fat and psoas major muscle, using peroperative fluoroscopy. Expandable retractor was inserted, discectomy and replacement by Oracle (Synthes, USA) cage (with synthetic cancellous bone graft) to the interbody space was performed. XLIF represents save surgical method with maximally careful approach and spacious working portal. The new benefit of XLIF is based on the minimally invasive spine surgery technique through retroperitoneal space. The lateral access to the disc avoids the major vessels and nerves and implant placement in the anterior and bilateral position provides sagital and coronal plane imbalance correction.

[Reliability of load-sharing classification in indications for anterior vertebral body replacement in thoracolumbar spine fractures]

INTRODUCTION

So far, the Load-Sharing Classification (LSC) has been the commonest method employed to identify indication for anterior replacement of vertebral bodies in thoracolumbar spine fractures. The aim of this study was to verify reliability of the LSC method in indications for anterior replacement surgery.

METHODS

Fractures were examined using x-ray, CT and MRI methods. The prospective study included only patients with type A3 comminuted fractures (AO classification) of the thoracolumbar vertebrae (Th11-L2), with MRI confirmed grade 3 or 4 intervertebral disc injuries (according to Oner) and with no concomitant nerve injuries. All fractures were treated using isolated posterior transpedicular (TP) fixation. 18 months after the procedure, angulation of the regional kyphosis, screw rupturing, Visual Analogue Scale (VAS) scores at rest and under loading, Pain Scale (PS) scores and Work Scale (WS) scores were assessed. The study group included 42 patients aged 27-72 years (the mean age was 51.55 y.o.a.), 28 subjects were males and 14 females. Using the LSC classification system, the study group was divided into two subgroups, one including patients with LSC up to grade 6 - Group A (18 subjects) and the other one including patients with LSC 7 to 9 - Group B (24 subjects).

RESULTS

Statistical assessment of clinical (PS, WS, VAS at rest and VAS after loading) and radiological findings (the degree of kyphotic changes) at month 18 identified no statistically significant correlations between the two subgroups. TP fixation failures (srews rupturing) occured only in Group A in two subjects.

DISCUSSION

Based on the LSC, Group B was expected to have inferior outcomes, however, this was not the case in our study group. Therefore, it can be concluded that LSC is not a reliable predictor of the final clinical and radiological findings in the type A3 fractures with grade 3 or 4 TH-L intervertebral disc injuries. The defined LSC 6- point threshold for indications for anterior vertebral body and disc replacements is arguable.

CONCLUSION

The authors do not consider the LSC method sufficiently reliable for determining indications for anterior replacements.

FDG uptake is a surrogate marker for defining the optimal biological dose of the mTOR inhibitor everolimus in vivo

This study aimed to test whether [¹⁸F]fluoro-D-glucose (FDG) uptake of tumours measured by positron emission tomography (PET) can be used as surrogate marker to define the optimal biological dose (OBD) of mTOR inhibitors in vivo. Everolimus at 0.05, 0.5, 5 and 15 mg kg⁻¹ per day was administered to gastric cancer xenograft-bearing mice for 23 days and FDG uptake of tumours was measured using PET from day 1 to day 8. To provide standard comparators for FDG uptake, tumour volume, S6 protein phosphorylation, Ki-67 staining and everolimus blood levels were evaluated. Everolimus blood levels increased in a dose-dependent manner but antitumour activity of everolimus reached a plateau at doses ⩾5 mg kg⁻¹ per day (tumour volume treated vs control (T/C): 51% for 5 mg kg⁻¹ per day and 57% for 15 mg kg⁻¹ per day). Correspondingly, doses ⩾5 mg kg⁻¹ per day led to a significant reduction in FDG uptake of tumours. Dose escalation above 5 mg kg⁻¹ per day did not reduce FDG uptake any further (FDG uptake T/C: 49% for 5 mg kg⁻¹ per day and 52% for 15 mg kg⁻¹ per day). Differences in S6 protein phosphorylation and Ki-67 index reflected tumour volume and changes in FDG uptake but did not reach statistical significance. In conclusion, FDG uptake might serve as a surrogate marker for dose finding studies for mTOR inhibitors in (pre)clinical trials.