Effect of DiscoGel treatment of the intervertebral disc at MRI.

AIM: To determine the impact of ethanol gel chemonucleolysis (EGCh) on the radiological picture of the treated intervertebral disc, the relationship between the initial radiological status and the clinical status of the patient after EGCh treatment, and the optimal radiographic criteria for qualifying a patient for EGCh treatment. MATERIALS AND METHODS: The study involved a group of 45 patients (25 men and 20 women) aged 23-68 years (46 ± 11) who underwent an EGCh procedure after qualification, radiography, and clinical questionnaire evaluation. RESULTS: The results showed a decrease in the size of the protrusion and Gadolinium-Enhanced (GI) zone in the treated intervertebral disc. The presence of a high-intensity zone (HIZ) on baseline magnetic resonance imaging was found to be a good predictor of the timing and outcome of treatment, and an increase in disc height was observed in adjacent segments. CONCLUSION: These findings suggest that EGCh is a promising treatment for spine diseases, and the HIZ on baseline magnetic resonance imaging can be used as a qualification criterion for this procedure.

Wavelet assessment of cerebrospinal compensatory reserve and cerebrovascular reactivity.

We introduce a wavelet transfer model to relate spontaneous arterial blood pressure (ABP) fluctuations to intracranial pressure (ICP) fluctuations. We employ a complex continuous wavelet transform to develop a consistent mathematical framework capable of parametrizing both cerebral compensatory reserve and cerebrovascular reactivity. The frequency-dependent gain and phase of the wavelet transfer function are introduced because of the non-stationary character of the ICP and ABP time series. The gain characterizes the dampening of spontaneous ABP fluctuations and is interpreted as a novel measure of cerebrospinal compensatory reserve. For a group of 12 patients who died as a result of cerebral lesions (Glasgow Outcome Scale (GOS) = 1) the average gain in the low-frequency (0.02- 0.07 Hz) range was 0.51 +/- 0.13 and significantly exceeded that of 17 patients with GOS = 2 having an average gain of 0.26 +/- 0.11 with p = 1x10(-4) (Kruskal-Wallis test). A time-averaged synchronization index (which may vary from 0 to 1) defined in terms of the wavelet transfer function phase yields information about the stability of the phase difference of the ABP and ICP signals and is used as a cerebrovascular reactivity index. A low value of synchronization index reflects a normally reactive vascular bed, while a high value indicates pathological entrainment of ABP and ICP fluctuations. Such entrainment is strongly pronounced in patients with fatal outcome (for this group the low-frequency synchronization index was 0.69 +/- 0.17). The gain and synchronization parameters define a cerebral hemodynamic state space (CHS) in which the patients with GOS = 1 are to large extent partitioned away from those with GOS = 2. The concept of CHS elucidates the interplay of vascular and compensatory mechanisms.

[Cranial epidural abscesses: a case report]. / Wewnatrzczaszkowy ropniak nadoponowy: opis przypadku.

OBJECTIVE AND IMPORTANCE: Cranial epidural abscess mostly follows sinusitis or mastoiditis, also open cranial injury or cranial surgery with iatrogenic infection. In our case the abscess possibly evolved from epidural haematoma and the process invaded frontal sinus and subgaleal space in the frontal region. CLINICAL PRESENTATION: A 22-year-old male after motorcycle accident 4 years ago, with signs of sinusitis frontalis and seizures, with CT confirmed epidural abscess. INTERVENTION: Craniotomy was performed and the abscess totally removed. Homogeneous bone was replaced at the operation. Good result, after 2 months without pathologic signs and correct postoperative tomography. CONCLUSION: We conclude on the basis of disease history and clinical evidence, that the most probable was transformation of the abscess from epidural haematoma end in long term period perforated through the frontal bone to the frontal sinus, and to the subgaleal space with signs of sinusitis at last.

[Acute post-traumatic epidural hematoma: report of 4 non-surgically treated cases]. / Ostry pourazowy krwiak nadtwardówkowy--opis czterech przypadków leczonych zachowawczo.

The authors present four cases of acute epidural hematoma (three supratentorial and one in the posterior fossa), in which non-operative treatment was performed. The conditions to undertake this treatment were: good clinical and neurological state of the patients on admission (GCS equal or more than 14), absence or mild focal symptoms and possibility to observe the patients and to perform CT follow-up. All patients had a good recovery. The authors discuss these cases and present the review of the literature concerning the problem.

A new anti-infective collagen dressing containing antibiotics.

A new antibacterial dressing for infected wounds was prepared. The dressing was composed of a collagen membrane and collagen sponge; both biomaterials possess good tissue biocompatibility. An active antibacterial layer of limited hydrophobicity was placed between the membrane and the sponge and into the upper part of the sponge. The dressing contained gentamycin or amikacin at concentrations of 0.3 microgram/cm2 (loading level of the drug utilized during preparation of the dressing). Either the antibiotic or its concentration easily can be changed in the dressing by the manufacturer. The dressing was stable for several months. The antibiotic was released slowly from the dressing in in vitro experiments for 3 days. Antibacterial activity of the dressing was tested using a mouse wound model experimentally infected with Pseudomonas aeruginosa. Both dressings, containing either amikacin or gentamycin, reduced the number of living bacterial cells in the infected tissue almost to zero during the course of observation. The new dressing may be effective in the treatment of infected wounds in patients.

Adaptive model-based motion estimation.

A general discrete-time, adaptive, multidimensional framework is introduced for estimating the motion of one or several object features from their successive nonlinear projections on an image plane. The motion model consists of a set of linear difference equations with parameters estimated recursively from a nonlinear observation equation. The model dimensionality corresponds to that of the original, nonprojected motion space, thus allowing to compensate for variable projection characteristics such as paning and zooming of the camera. Extended recursive least-squares and linear-quadratic tracking algorithms are used to adaptively adjust the model parameters and minimize the errors of either smoothing, filtering or prediction of the object trajectories in the projection plane. Both algorithms are derived using a second order approximation of the projection nonlinearities. All the results presented here use a generalized vectorial notation suitable for motion estimation of any finite number of object features and various approximations of the nonlinear projection. The application of the model-based motion estimator for temporal decimation/interpolation in digital video sequence compression systems is presented.