Comparative structural and optical properties of different ceria nanoparticles.

Herein a comparative study of five nanocrystalline cerium oxides (CeO(2-delta)) synthesised by different methods and calcined at 500 degrees C is reported. XRPD analysis showed that stoichiometry parameter delta, crystallite size/strain and lattice constant were only slightly affected by the method utilized. All ceria nanoparticles are nearly spherical in shape with faceted morphology, free of defects and with a relatively uniform size distribution. The average microstrain was found to be approximately 10 times higher than that of bulk counterpart. The absorption edge of nanocrystalline materials was shifted towards a higher wavelengths (red shift) in comparison with bulk counterpart, and band gap values were in the range 2.7-3.24 eV (3.33 eV for bulk counterpart).

Effects of Eu3+ concentration on structural, optical and vibrational properties of multifunctional Ce(1-x)Eu(x)O2-delta) nanoparticles synthesized by thermolysis of 2,4-pentanedione complexes.

The 5-10 nm Ce(1-x)Eu(x)O(2-delta) (0 < or = x < or = 0.30) nanoparticles with fluorite structure were synthesized by thermal decomposition of Eu- and Ce-2,4-pentanedione complexes mixtures. X-ray line broadening analysis of mixed samples Ce(1-x)Eu(x)O(2-delta) (0.05 < or = x < or = 0.30) showed that the crystallite size was lower and root mean square strain higher than in pure ceria. However, within mixed samples Ce(1-x)Eu(x)O(2-delta) (0.05 < or = x < or = 0.30) crystallite size and root mean square strain were independent of Eu3+ concentration. Raman spectroscopy results indicated that europium ions yield disorder by breaking the phonon propagation and therefore making the non-centre Brillouin zone modes Raman active. The absorption bands in the spectra of mixed oxides were blue-shifted in comparison to pure CeO(2-delta) nanopowder. The samples show red emission typical for Eu ions. The biggest photoluminescent intensity was observed for the highest Eu3+ concentration (x = 0.30) and further enhanced with the increase in crystallinity.

[Injuries of the cervical spine in motorcycling and bicycling traffic accidents].

Due to the vehicle characteristics neck injuries are common in motorcycle and moped users involved in traffic accidents. We are reporting on neck injuries amongst 502 fatalities of drivers and passengers of motorcycles and mopeds, and cyclists. Cervical spine injuries were found in 124 cases (24.7%). Cervical spine injury was statistically significantly more frequently in passengers (61.9%) compared to the drivers (20.7%) of motorcycle and moped (chi2 = 13.384; p < 0.01), the lesions are usually localized in the upper cervical spine (52.4%), the most frequently at atlantoocciptal region (F = 25.835; p); these injuries were most frequently caused by frontal (31.45%) or rear (50.81%) axial collisions. Almost all cases of cervical spine injuries were present without apparent external injuries; they were associated with lesions of neck muscles, blood vessels and/or neck organs, and in 79 cases (63.7%) there was a lesion of the cervical spinal cord. The research results indicate a large incidence of neck injuries in traffic accidents especially in motorcycle, moped and bicycle axial collision with the possible absence of external injuries, which may represent a clinical and forensic problem.

Optimization of photoluminescence of Y(2)O(3):Eu and Gd(2)O(3):Eu phosphors synthesized by thermolysis of 2,4-pentanedione complexes.

Spherical shaped nanoparticles of series Y(2 - x)Eu(x)O(3) (x = 0.06, 0.10, 0.20, and 2) and Gd(2 - x)Eu(x)O(3) (x = 0.06, 0.10) were prepared by thermolysis of 2,4-pentanedione complexes of Y, Gd, and Eu. The bixbyite phase of Gd(2 - x)Eu(x)O(3) samples was formed at 500 degrees C, whereas the thermal decomposition of Y and Eu complexes' mixtures occurred at higher temperatures. Linearity in the concentration dependence on lattice parameter confirmed the formation of solid solutions. The distribution of Eu(3+) in Gd(2 - x)Eu(x)O(3) was changed with thermal annealing: in the as-prepared sample (x = 0.10) the distribution was preferential at C(3i) sites while in the annealed samples, Eu(3+) were distributed at both C(2) and C(3i) sites. Rietveld refinement of site occupancies as well as emission spectra showed a random distribution of cations in Y(2 - x)Eu(x)O(3). The photoluminescence (PL) measurements of the sample showed red emission with the main peak at 614 nm ((5)D(0)-(7)F(2)). The PL intensity increased with increasing concentration of Eu(3+) in both series. Infrared excitation was required to obtain good Raman spectra. The linear dependence of the main Raman peak wavenumber offers a non-destructive method for monitoring the substitution level and its homogeneity at the micron scale.

[Disease of lower cranial nerves caused by vascular compression].

Between April 1989 and September 2007, 181 patients with disease of lower cranial nerves (DLCN) underwent posterior fossa exploration. As a cause of DLCN, vascular compression (VC) was present in 89 patients with trigeminal neuralgia (TN), in 6 with hemifacial spasm (HFS), in 1 with glossopharyngeal neuralgia, in 1 with Meniere's disease, and in 5 with multiple DLCN. Depending on intraoperative findings, different surgical options were used: microvascular decompression (MVD), MVD with partial sensory rhizotomy (PSR) or total sensory rhizotomy (TSR). Statistic analysis was made using the Fisher's exact 2-side test. In patients with TN, excellent outcome was archived in 83 patients and good in 6. Postoperative outcome was better (p = 0.007) in cases with severe VC, but without significant correlation between used surgical option and outcome (p = 0.402). Frequency rate of relapses did not depend on severity of VC (p = 0.502) and used surgical option (p = 0.175). In 6 patients with HFS, excellent outcome was archived in 5 with arterial compression and poor in 1 with venous contact. In patients with Meniere's disease and glossopharyngeal neuralgia, MVD result with excellent outcome. In 5 patients with multiple DLCN, excellent outcome was archived in 3 and good in 2. MVD is method of choice in surgical treatment of DLCN caused by VC. Overall outcome is better with severity of VC.

[Indications for surgical treatment of pain and types of operations]. / Indikacije za hirursko lecenje bola i vrste operacija.

During the period from 1978 to 2003 in Institut for neurosurgery CCS and Neurosurgical hospital of MA in Belgrade, 3057 patients with pain syndroms in different localisations were operated. Before operation all conservative methods were exhausted. We made 248 microvacular decompressions in fossa cranii posterior, 1600 radiophrequent lessions of ggl. Gasseri and 64 avulsions of distal trigeminal branches in patients with trigeminal and glossopharingeal neuralgia, 128 chordotomies in patients with neurogenic and cancer pain, 62 DREZ operations in patients with paraplegia, cancer pain and postherpetic intercostal neuralgia. More than 900 patients have been operated because of neuropathic pain and trauma of peripheral nerves, and 48 patients were operated due to Phantomzs pain. We compared results of two alternative methods in treatment of trigeminal neuralgia (radiophrequent lesion of ggl. Gasseri and microvascular decompression in posterior fossa).

[Neuralgias of the lower cranial nerves: microsurgical posterior fossa exploration]. / Neuralgije donje grupe kranijalnih nerava: mikrohirurska zadnjelobanjska eksploracija.

Neuralgias of the lower cranial nerves are trigeminal neuralgia (TN), glossopharingeal neuralgia (GphN), and geniculate neuralgia (GN). Microsurgical posterior fossa exploration with its variations microvascular decompression (MVD), partial sensory rhisotomy (PSR), and total sensory rhisotomy (TSR) is one of the most efficient ways of treating these neuralgias. It was performed 130 operations in 125 patients with TN, 3 in GphN patients, 1 in GN patient, 1 in GN/TN patients, 1 in GphN/GN patient, and 2 in GN/hemifacial spasm patients. Of total of 125 patients with TN, MVD was performed in 63, PSR in 18, and MVD+PSR in 44 cases. In 5 patients with recidivate TN PSR was performed. Of total 3 patients with GphN MVD was performed in 2 cases, and extirpation of a small meningeoma in 1 case (it was not seen on CT). In the patients with GN TSR of intermediate nerve was performed, in GN/TN patients TSR of intermediate nerve and PSR of trigeminal nerve was performed, in the GN/GphN patients MVD of glossopharingeal and TSR of intermediate nerve were performed, and in the GN/hemifacial spasm patients TSR of intermediate and MVD of facial nerve were performed. The results of TN patients are: excellent in 82.4%, good in 12%, and poor in 5.6% of patients. There is no difference in complete pain relief, rate of recurrence, and complications between MVD, MVD+PSR and PSR operative groups (p0.05). Among patients with other neuralgias the following results are noted: excellent in 4, good in 3, and poor in 1 patient. Microsurgical posterior fossa exploration is the method of choice in the treatment of the neuralgias of the lower cranial nerves.

[Cordotomy in the treatment of pain conditions]. / Hordotomija u lecenju bolnih stanja.

During the time interval from January 1978 to January 2003, total of 128 chordotomy procedures have been done due to cancer's pain at the Institute of neurosurgery in Clinical Centre of Serbia. That pain has been mostly of uncontrolled intensity and it was resistant on applieed conservative treatment. Bilateral chordotomy has been performed in 6 patients only in exceptional cases when fixed paraplegia has proved; unilateral chordotomy has been performed in 122 cases. Bilateral chordotomy is much more dangerous than unilateral one because of greater posibility of appearance of motor deficits, sphincteral disturbances or subsequent formed pain. This procedure has several negative aspects. Firstly, it is an opened surgical intervention in general anesthesia and therefore, there is no communication with patient. We had a habit to perform DREZ surgery rather than chordotomy when ever it has been indicated. In 80.1% of all cases, the successfulness of surgery has been marked as excellent, in 15.2% of all cases, it has been marked as good, and in 4.7% of all cases, bad outcome has been detected. The rate of complication was 4.4%.

[DREZ (dorsal root entry zone) surgery for the treatment of the postherpetic intercostal neuralgia]. / Lecenje postherpeticne interkostalne neuralgije DREZ operacijom.

Postherpetic intercostal neuralgia proved to be an incapacitating pain often recalcitrant to therapy. Acute pain that accompanied Herpes zoster usually subsides spontaneously but in 10% of patients the pain persists and intensifies. The incidence of postherpetic neuralgia incrises up to 50% among elder patients. We report the case of the two 42 and 48 yers old male patient who were succesfuly relieved from the chronic postherpetic intercostal neuralgia employing the DREZ surgery (Dorzal Root Entry Zone lesion). DREZ surgicall treatment of this pain should be considered when medical therapies failed in controling pain. Subjective sensory nature of the pain should play an important role in setting the indication for DREZ surgical treatment. The most favourable pain pattern for DREZ operation is the pain of intermittent rhythm, confined theritory accompanied with the phenomenon of alodinic pain that could be provoked from the pain theritory.

[Biomechanical characteristics of spinal cord tissue--basis for the development of modifications of the DREZ (dorsal root entry zone) operation]. / Biomehanicke karakteristike tkiva kicmene mozdine--osnov za razvoj modifikovane tehnike DREZ operacije.

Mechanical properties of the spinal cord tissue--biological basis for the development of the modality of the DREZ surgery lesioning technique Succesful treatment of the chronic neurogenic pain of spinal cord and cauda equina injury origin remains a significant management problem. The mechanism of this pain phenomenon has been shown to be related to neurochemical changes that lead to the state of hypereactivity of the second order dorsal horn neurons. The DREZ surgery (Dorsal Root Entry Zone lesion), designed to destroy anatomy structures involved in pain generating thus interrupting the neurogenic pain mechanism, as a causative procedure in treating this chronic pain, has been performed by using different technical modalities: Radiofrequency (RF) coagulation technic, Laser, Ultrasound and Microsurgical DREZotomy technic. The purpose of the study was to assess the possibility for the establishment of the lesioning technic based on the natural difference in the mechanical properties between the white and gray cord substance. We experimentally deteminated mechanical properties of the human cadaveric cord white versus gray tissue for the purpose of testing possibility of selective suction of the dorsal horn gray substance as a DREZ lesioning procedure. Based on the fact of the difference in tissue elasticity between white and gray cord substance we established a new and simple DREZ surgical lesioning technique that was tested on cadaver cord. For the purpose of testing and comparing the size and shape of the DREZ lesion axchieved the DREZ surgery has been performed on cadaver cord by employing selective dorsal horn suction as a lesioning method. After the procedure cadaver cord underwent histological fixation and analysis of the DREZ lesions achieved. Our result revealed that the white cord substance with longitudinal fiber structure had four time higher dynamical viscosity than gray substance of local neuronal network structure (150 PaS versus 37.5 PaS) that provided possibility for the safe and selective suction of the gray substance of the dorsal horn. Technic includes incision of the dorsolateral sulcus according to Sindous Microsurgical DREZotomy technic than suction under visual control of the dorsal horn gray matter using succer adopted from the lumbar puncture nidle. Operative experimental testing and hystological analysis confirmed expected size and shape of the DREZ lesion performed by dorsal horn suction as DREZ lesioning technique. The utility, selectivity and safety of this technic has been provided by the natural mechanical properties of the cord tissue itself. Application of the Dorsal horn suction as a DREZ lesioning in humans confirmed this technic as a safe and reliable DREZ lesioning method.

[Surgical treatment of hypophyseal adenoma using the pterional approach]. / Hirursko lecenje adenoma hipofize pterionalnim pristupom.

The results of a retrospective study of 21 patients undergoing surgery with pterional approach to pituitary adenomas are reported. There were 7 females, and 14 males, between 20 to 68 (average 43.5) years of age. According to adenoma extension 6 patients were with type III-A (suprasellar-suprachiasmatic), 4 with type III-B (suprasellar-retrosellar), 6 with type III-C (parasellar-cavernous), and 5 with type III-D (paninvasive). According to adenoma size there was 1 patient with small (5 mm-2 cm), 11 with moderate (2-4 cm), 4 with large (4-6 cm), and 5 patients with paninvasive adenomas. Histopathological examination showed null cell in 11, growth-cell in 6, prolactin-cell in 1, and plurihormonal adenomas in 3 cases. Two patients have died. The cause of death was hypothalamic lesion or cerebral infarct.

[Lateral orbitotomy in the approach to an orbital dermoid cyst]. / Lateralna orbitotomija u pristupu orbitalnoh dermoidnoj cisti.

The choice of surgical approach for the resection of orbital tumor is as a rule determined by the tumor position in the orbital space and the best choice is the most direct approach to orbital tumor. Lateral orbitotomy as the extracranial orbital approach is favorable for radical resection of the tumor, which growth is limited to the anterior, lateral and superolateral orbital segment.

[Secondary neurosurgical management of craniocerebral war injuries]. / Sekundarno neurohirursko zbrinjavanje ratnih kraniocerebralnih povreda.

In Belgrade Military Medical Academy 88 males and 1 female (aged 13-55, average 28.6 years) with war craniocerebral injuries (CCI) were secondarily neurosurgically treated from October 1991 trough December 1992. Primary neurosurgical management of these patients was performed in war hospitals in former Yugoslavia. Out of 89 patients, 78 had penetrating, and 11 closed CCI. Out of 55 patients with penetrating CCI who underwent surgery, intracranial debridement was performed in 34 patients. All patients with severe CCI (GCS = 3-8) were severely by disabled or died, and in the majority of patients with minor CCI (GCS = 13-15) the outcome was good (p < 0.01). Statistical analysis showed no significant correlation between the extent of cerebral lesion and the outcome of penetrating CCI (p > 0.05). Eight (10.3%) patients with penetrating CCI died. The outcome of war CCI mostly depended on the severity of injury.

[Transnasal transsphenoidal approach to pituitary adenomas]. / Transnazalni transsfenoidni pristup adenomima hipofize.

The results of transnasal transsphenoidal surgery of pituitary adenomas were retrospectively analyzed in a group of 42 patients, 22 females and 20 males, aged 19-70, of average age 43 years. Histopathological examination showed null-cell adenomas in 4, growth-cell in 11, prolactin-cell in 3, adrenocorticotropin-cell in 6, plurihormonal adenomas in 6, craniopharingeoma in 1, metastasis of pulmonary carcinoma in 1, pituitary abscess in 1, and normal pituitary tissue in 9 cases, respectively. Out of 30 patients with adenomas, 21 had macro (> 1 cm) and 9 had microadenomas (< 1 cm). Cerebrospinal fluid leakage (8.7%) and meningitis (6.5%) were the most frequent postoperative complications. There was no operative mortality. Full adenoma recurrence (clinical, hormonal, and radiological) was found in 3, clinical and hormonal in 3, hormonal and radiological in 1, and radiological in 2 patients, respectively. The repeated transsphenoidal surgery was performed in 4 patients. The transnasal transsphenoidal approach is the procedure of choice for surgical treatment pituitary adenomas.

[Primary neurosurgical treatment of craniocerebral war injuries]. / Primarno neurohirursko lecenje ratnih kraniocerebrumskih povreda.

From September 1991 to December 1992, 41 patients with nonpenetrating and 84 patients with penetrating craniocerebral injuries were neurosurgically treated at the Military Medical Academy. The severity of injuries was estimated according to GCS and the outcome according to GOS. In 17 out of 27 patients with moderate nonpenetrating CCI, the outcome was favorable, and 5 patients out of 7 with severe CCI died (p < 0.01). Out of 33 patients with moderate penetrating CCI, favorable outcome or moderate disability were observed in 21 patients, and out of 26 patients with severe CCI, 19 died (p < 0.01). The majority of unilobar CCI resulted in favorable outcome or moderate disability, while 10 out of 26 patients with multilobar CCI, as well as 9 out of 16 patients with bichemispheric CCI died (p < 0.01). Mortality rate in patients with penetrating CCI was 25%. No significant differences were observed in the outcome of penetrating CCI in relation to the missile type (p > 0.05). Nonpenetrating CCI had a better outcome than the penetrating ones (p < 0.05). The outcome of war nonpenetrating CCI depended on the severity of injury and of penetrating CCI on the severity injury, of the extent of cerebral lesion and the form of penetration, respectively.

[Results of repair of severed nerves in war injuries]. / Rezultati reparacije ratnih neurotmeza.

The results of surgical treatment of 397 wounded with 482 neurotmeses (64 median, 97 ulnar, 100 radial, 7 musculocutaneal, 120 peroneal and 94 tibial nerves) were analyzed. The treatment outcome was determined 12-36 months postoperatively by analyzing the sensorimotor recovery, EMNG status and operated person's attitude to the repair outcome. The change of all the four mentioned parameters was graded from 0 to 5 points, and the outcome was qualified as poor, moderate, good or excellent according to the point sum total. The majority of good and excellent results was obtained after radial (85%) and musculocutaneal (100%) nerve repairs and the less after peroneal nerve repair (13.3%). Based on the obtained results, it was concluded that radial and musculocutaneal neurotmeses should always be repaired, disregarding the height of lesion. Repair of high ulnar and peroneal lesions was unsuccessful. High lesions of tibial and median nerves should be repaired because of the possible recovery of protective sensibility in autonomous nerve zone.

[Craniocerebral injuries at the Vukovar battlefield]. / Kraniocerebralne povrede sa vukovarskog ratista.

In Neurosurgical Clinic of Military Medical Academy 33 wounded persons with craniocerebral injuries (CCI) from Vukovar battlefield were treated from September 16 to December 3. After the follow-up period of average 48 months the outcome of treatment was analyzed compared to the clinical status on admission and to the extent of cerebral lesion. All wounded with minor CCI (GCS = 15) and majority with mild injuries (GCS = 13-14) had the good outcome, and all the wounded with severe injuries (GCS = 3-8) died (p < 0.01). After unilobar penetrating CCI the outcome was mostly good, but after multilobar and transventricular injuries the outcome was worse or lethal (p < 0.01). Total mortality rate was 27.3%. Our conclusion is that bad clinical status on admission and more extensive cerebral lesions correlate with worse outcome of treatment of war CCI.