Evaluation of the Efficacy of Sildenafil Citrate Following Severe Head Trauma in an Experimental Rat Model.

AIM: To investigate the acute effects of sildenafil citrate in an experimental model of severe head trauma, and to compare it with the efficacy of mannitol, which is an osmotically active agent frequently used in clinical treatment of traumatic brain injury (TBI). MATERIAL AND METHODS: Twenty-eight Wistar-derived albino strain female rats were randomized into four groups comprising seven rats each. These groups were designated as follows: Group I: sham; Group II: TBI; Group III: TBI + mannitol (20% 1 gr/ kg, intraperitoneal); and Group IV: TBI + sildenafil citrate (10 mg/kg, intraperitoneal). Sections prepared following the tissue processing of samples obtained from the right prefrontal cortex and right hippocampal regions of the brains of sacrificed rats were histopathologically evaluated. Fractionator method via the Stereo Investigator software program (Micro Bright Field) was used to count the neurons. Pyknotic neuron count and pyknotic / total neuron count were compared between the groups. RESULTS: In the comparison of Group II and IV, pyknotic neuron count (prefrontal; group II: 116.00 ± 30.50, group IV: 80.00 ± 19.47) and pyknotic/ total neuron count (prefrontal; group II: 0,30 ± 0.08, group IV: 0.21 ± 0.02) were significantly lower in Group IV in both regions (p < 0.05). Similarly, in the comparison of Group II and III, the values in Group III were lower in both regions (p < 0.05). CONCLUSION: Sildenafil citrate decreases neuronal death in the acute phase and produces similar results with mannitol. Therefore, we believe that sildenafil citrate can be a useful adjunct or alternative agent for the clinical treatment of patients with acute TBI.

Stereological Evaluation of the Optic Nerve Volume in Alzheimer Disease.

Optic nerve damage occurs in Alzheimer disease (AD) related to the loss of the retinal ganglion cells that contribute fibers to the optic nerve and reduction of the density of axons of the optic nerve. In this study the authors evaluated optic nerve volume changes and the relation between the cerebrum and optic nerve volumes in AD patients. The study evaluated the volumetric measurements of optic nerve by applying the stereological method on magnetic resonance images (MRI). It included age-matched study and control groups, which were composed of 20 patients with probable AD and 20 healthy subjects, respectively. MRIs were analyzed by using the point-counting approach holding Cavalieri principle. There were statistically significant optic nerve volume reduction and cerebral atrophy in AD patients when compared with the age-matched control subjects (P = 0.013, P < 0.001, respectively) but there was no correlation between the optic nerve volume and cerebral volume in AD patients (r = 0.326, P = 0.160). There was a difference between optic nerve volumes of AD and control subjects. The stereological evaluation of optic nerve volume is of importance for both clinicians and anatomists and it can provide valuable information in the evaluation of morphological changes of AD in vivo.

Comparison of the Effects of 13-cis Retinoic Acid and Melatonin on the Viabilities of SH-SY5Y Neuroblastoma Cell Line.

OBJECTIVE: Neuroblastoma is one of common childhood tumors. Although its mortality is very high, there is no effective treatment yet. The aim of this project is to evaluate cytotoxic effects of melatonin (MLT) an endogen hormone and 13-cis retinoic acid (13-cis-RA) also named as isotretinoin an analogue of vitamin A on neuroblastoma SH-SY5Y cell line. METHODS: In this study, SH-SY5Y cell line was used. After cell culture, the cells were exposed to different doses of MLT and 13-cis-RA. 24 and 48 hours later. While the viabilities was estimated with MTT cell viability assay test, apoptotic indexes were calculated after staining with TUNEL based apoptosis kit. RESULTS: It was observed that MLT has very effective cytotoxic potential than 13-cis-RA on neuroblastoma cell line. At the same time, when MLT and 13-cis-RA were combined, this effect was potentiated. On the other hand, it was found that the effect of 13-cis-RA individually on neuroblastoma cells was very slight. CONCLUSION: We suggest that in the treatment of patient with neuroblastoma, MLT is very effective and also this effect can be augmented by combination with 13-cis-RA.

Unusual scalp metastasis from follicular thyroid carcinoma.

Metastatic tumors presenting as soft tissue lesions are relatively rare, and can be the source of diagnostic confusion both clinically and histopathologically. We present a case of an 82-year-old woman with complaints of painless swelling in the right temporo-occipital junction for 3 months, and with unusual scalp metastasis of thyroid follicular carcinoma. Use of histopathological examinations are significant for determining the tumor type, and arriving at the exact and correct diagnosis.

Lumbar vertebra morphometry and stereological assesment of intervertebral space volumetry: a methodological study.

The use of technology in the treatment of degenerative spinal diseases has undergone rapid clinical and scientific development. It has been extensively studied in combination with various techniques for spinal stabilization from both the anterior and posterior approach. Minimally invasive and instrumental approach via posterior fixation is increasingly being used for the treatment of adult degenerative disc disease, stenosis, and deformity of the lumbar vertebrae. Posterior access to the lumbar disc spaces for posterolateral fusion scan has been technically challenging, frequently requiring the use of an approach surgery for adequate exposure. For successful surgery and suitable instrumental design, adequate anatomical knowledge of the lumbar vertebra is also needed. Anatomic features of lumbar vertebrae are of importance for posterior screw fixation technique. The morphometry of L1-L5 has been studied to facilitate the safe application of pedicle screws. Thus, we aimed to evaluate the morphometric landmarks of lumbar vertebrae such as pedicle, vertebral body, vertebral foramen, intervertebral space height and volume for safe surgical intervention using a posterior fixation approach to offer anatomical supports for lumbar discectomy, stenosis and cases of deformity. The features of the L1-L5 vertebral body, the detailed morphometric parameters of lumbar vertebrae and the intervertebral space were analyzed using computerized tomography scan, magnetic resonance imaging and also dry lumbar vertebrae. Additionally, intervertebral space volumes were measured using stereological methods to ensure safe surgical intervention.

Evaluation of lumbar vertebral body and disc: a stereological morphometric study / Evaluación del cuerpo y disco vertebral lumbar: estudio morfométrico estereológico

Anterior access to the L1-L5 vertebrae and disc spaces can be technically challenging, frequently requiring the use of an approach to a surgeon for an adequate exposure. The technique is used for lesion excision, corpectomy, vertebral body reconstruction with cages, realignment, and/or plating or screwing. For a successful anterior approach and a suitable instrumental design via screw, adequate morphometric knowledge about body of lumbar vertebrae and disc spaces and standardized volumetric data are also required for neurosurgeons. We aimed morphometric and volumetric evaluation of lumbar bodies and discs to contribute to a safe anterior approach during surgery. We evaluated vertebral body and disc morphometry using stereology in right-handed 25 adult subjects on MRI in the same population with no history of vertebral fractures and degenerative spinal disease. The shape, defining concavity index and volumetric measurements of the body L1-L5 vertebrae, morphometric parameters such as length, height, width of the vertebral body were measured. Also morphometric and volumetric analysis of discs between L1 and L5 were evaluated selected axial and sagittal slices. As expected, the average dimensions of male vertebrae are greater than those of females, but most of them do not differ statistically. Only three dimensions, the mean difference between anterior and central heights of L3, L4 and L5 showed statistically significant difference, indicating smaller central height in both males and females.The transverse and anterior-posterior diameters of the vertebral body, intervertebral disc height and volume displayed no sexual dimorphism (p>0.05). But, the intervertebral disc height and volume increased from L1 to L5 (p <0.01). Concavity indexes for all lumbar vertebrae for both sexes did not differ statistically. The method is important to estimate applying implant size and amount in decompression operations for neurosurgeons.

El acceso anterior a las vértebras L1-L5 y espacios entre los discos puede ser técnicamente difícil, con frecuencia requiere la participación de un cirujano para una exposición adecuada. La técnica se utiliza para la extirpación de la lesión, corpectomía, la reconstrucción del cuerpo vertebral con jaulas, realineamiento y / o placas o tornillos. Para un enfoque exitoso anterior y un diseño adecuado instrumental a través de tornillo, un acabado conocimiento sobre la morfometría del cuerpo de las vértebras lumbares y de los espacios entre los discos y la evaluación volumétrica son necesarias para el neurocirujano. El objetivo fue la evaluación morfométrica y volumétrica de los cuerpos lumbares y los discos, para contribuir al abordaje seguro durante la cirugía. Se evaluó en 25 sujetos adultos, diestros, sin antecedentes de fracturas vertebrales y de enfermedad degenerativa espinal, el cuerpo vertebral y la morfometría del disco mediante estereología con RM. La forma de las vértebras, el índice de concavidad y la definición de las medidas volumétricas de los cuerpos L1-L5. Además, se midieron los parámetros morfométricos como longitud, altura, ancho del cuerpo vertebral. Se efectuó un análisis morfométrico y volumétrico de loss cortes axiales y sagitales de los discos entre L1 y L5. Como era de esperar, las dimensiones promedio de las vértebras en los hombres fueron mayores que en las mujeres, pero la mayoría de ellos no son estadísticamente significativas. Sólo tres dimensiones, la diferencia promedio entre la altura anterior y central de las vertebras L3, L4 y L5 mostraron diferencias estadísticamente significativas, indicando menor altura central tanto en los hombres como en las mujeres. Los diámetros transversal y anteroposterior del cuerpo vertebral, la altura del disco intervertebral y el volumen no mostraron dimorfismo sexual (p> 0,05). Sin embargo, aumentaron la altura del disco intervertebral y el volumen de L1 a L5 (p< 0,01). Los índices de concavidad...

Evaluation of cerebellar and cerebral volume in migraine with aura: a stereological study.

Migraine is associated with an increased risk of deep white matter lesions and subclinical posterior circulation infarcts. A significant association between deep white matter hyperintensities and cerebral atrophy is true for various neurological diseases; it was not specifically proven in migraine. The aim of this study was to evaluate the cerebellar and cerebral volume and volume ratios for cerebellum using the Cavalieri principle. We also aimed to examine whether migraine with aura causes cerebellar and cerebral atrophy. Twenty three right-handed patients with migraine with aura diagnosed by means of the International Headache Society criteria and 24 age-matched subjects whose only health problem was headache due to rhinosinusitis and tension type headache were included in the study. Measurements of the cerebellar and cerebral volumes as well as cerebellar/cerebral volume ratios were made using Cavalieri's principle by utilizing the point-counting methods. There were no significant differences between the volumes of cerebrum, cerebellum, and the ratio of cerebellum to cerebrum for males (p = 0.05, p = 0.10, and p = 0.64, respectively) and for females (p = 0.18, p = 0.89, and p = 0.24, respectively). Our results suggest that patients with migraine with aura do not have a significant difference in cerebellar and cerebral volumes and cerebellar/cerebral volume ratios compared to the non-migraine group.

Determining entropy values equivalent to the bispectral index values during sevoflurane anaesthesia.

INTRODUCTION: We aimed to identify the entropy levels that would be equivalent to the bispectral index (BIS) levels in sevoflurane anaesthesia in patients who are to undergo elective lumbar disc surgery. MATERIAL AND METHODS: Thirty cases in ASA groups I-II who underwent lumbar disc surgery under general anaesthesia were included in our study after obtaining the consent of the patients and Ethics Committee of our medical school between January 1, 2005 and October 30, 2006. BIS and entropy electrodes were applied at the same time in 30 cases in the study group. The depth of the anaesthesia was regulated so that 10 min after beginning the general anaesthesia the BIS values were between 40 and 60. At the same time equivalent entropy values corresponding to BIS values were obtained. RESULTS: At the end of the study, entropy values corresponding to general anaesthesia BIS values were identified. General anaesthesia BIS and RE/SE values at 10 min were lower than the values of the control, which was statistically significant (p < 0.05). Equivalent entropy values were obtained lower than the BIS values during general anaesthesia and these values were found to be statistically significant (p < 0.05). The blood pressure (BP) values obtained were very low at equivalent BIS values and when these BP values were compared with the initial BP values they were found to be statistically significant (p < 0.05). CONCLUSIONS: Based on this observation, we think that general anaesthetic agents that might cause severe hypotension could be more safely administered under entropy monitoring.

Effect of ligamenta flava hypertrophy on lumbar disc herniation with contralateral symptoms and signs: a clinical and morphometric study.

INTRODUCTION: The purpose of this study was to determine whether ligamentum flavum hypertrophy among disc herniated patients causes contralateral pain symptoms. For this reason we measured the thickness of the ligament in disc herniated patients with ipsilateral or contralateral symptoms. MATERIAL AND METHODS: Two hundred disc herniated patients with ipsilateral symptoms as group I were compared with five disc herniated patients with only contralateral symptoms as group II. Ligamenta flava thicknesses and spinal canal diameters of both groups were measured on magnetic resonance imaging (MRI) with a micro-caliper. RESULTS: Both groups underwent surgery only on the disc herniated side. The total thicknesses of the ligamenta flava in group II was thicker than in group I. There was no spinal stenosis in either group and no significance difference between the groups. Statistically significant differences were found for both ipsilateral and contralateral thickness of the ligament flava in both groups. We also compared thickness of the ligamenta flava for each level of disc herniation in group I; ligamenta flava hypertrophy was more common at L3-L4 and L4-L5 levels of vertebrae in females. CONCLUSIONS: Aetiology of contralateral sciatica among disc herniated patients may be related to hypertrophy of the ligamenta flava, especially on the opposite side. Surgical approaches of the disc herniated side alone may be sufficient for a good outcome.

Evaluation of cerebellar asymmetry in Alzheimer's disease: a stereological study.

OBJECTIVES: Alzheimer's disease (AD) is the most common cause of dementia and, as previous studies have indicated, degenerative changes in the cerebellum occur in AD. It is well known that the cerebellum does not have a symmetric morphology and some pathological disorders, such as schizophrenia, epilepsy, autism and alcoholism, can cause asymmetrical changes in the cerebellum. In this study, we aimed to evaluate whether or not patients with AD show cerebellar asymmetry. We also intended to depict the probable volumetric asymmetry by using a stereological technique. MATERIALS AND METHODS: The study evaluated the volumetric measurements of each cerebellar hemisphere by applying a stereological method to MR images. This age- and gender-matched study was composed of 15 patients with probable AD and 14 healthy subjects (controls). MR images were analyzed by using the point-counting approach, holding to Cavalieri's principle. RESULTS: Although there was significant cerebellar atrophy in AD patients, the study showed no statistically significant cerebellar asymmetry according to age and gender, both in the study and control groups (p > 0.05). CONCLUSIONS: There was no difference in cerebellar asymmetry associated with age and gender between the AD patients and control subjects. The stereological evaluation of cerebellar asymmetry correlating with gender is of importance to both clinicians and anatomists. The technique is simple, inexpensive, reliable and unbiased.

The premasseteric branch of facial artery: its importance for craniofacial surgery.

AIM: The masseter muscle is often exploited by craniofacial surgeons in transposition operations to correct facial palsy, benign masseteric hypertrophy; or neurectomy-induced atrophy of the muscle. A clear understanding of the course of the premasseteric branch of the facial artery and its relations with adjacent structures is essential in maneuvering the masseter muscle safely. In the present study the premasseteric branch was analyzed in details. MATERIAL AND METHODS: Neurovascular and anatomical features and relations of the premasseteric branch and its branches were evaluated according to location, origin, diameter, length and course by bilateral meticulous anatomic micro dissection under 4x loop magnification in formalin fixed 14 adult preserved cadavers. RESULTS: The premasseteric branch originated separately from the facial artery in all cases. The course of the branch was observed to the upper anterior border of the masseter muscle. The diameter of the premasseteric branch was 1.12 mm (mean) at the level of origin. The diameter of the premasseteric branch was larger than the facial artery in 3% of cases. The location of the branch was defined according to body of the mandible. Branches and anastomoses of the premasseteric branch were also represented. CONCLUSION: Anatomical data of the premasseteric branch will help craniofacial surgeons elevate flaps safely.

Stereological evaluation of the volume and volume fraction of intracranial structures in magnetic resonance images of patients with Alzheimer's disease.

In this study, we describe and adapt the relevant methods of magnetic resonance (MR) and stereology to estimate total brain volume (TBV), cerebral and cerebellar volume and their volume fractions within the brain. The study included 15 (8 males, 7 females) controls and 15 (8 males, 7 females) patients with Alzheimer's disease. The patients' MR images were obtained in both sagittal and axial planes. The volume and volume fraction of the total brain, cerebrum and cerebellum were determined on MR images using the point-counting approach of stereological methods. The volume fractions of the cerebrum to TBV and cerebellum to TBV in the control group were 66.38% and 67.87% in axial and sagittal planes, and 12.05% and 12.81% in axial and sagittal planes, respectively. The volume fractions of the cerebrum to TBV and cerebellum to TBV in the Alzheimer group were 52.40% and 56.26% in axial and sagittal planes, and 10.00% and 10.38% in axial and sagittal planes, respectively. The Alzheimer subjects showed significantly lower cerebral and cerebellar volume fraction to TBV than the control subjects (p<0.001). No significant difference was found in either group with regard to gender or planes (p>0.05). The present evaluation of TBV, cerebral and cerebellar volume and volume fractions can be done on any complete set of MR imaging, in which the plane scan distance and magnification factor are known, as they are in MRI. In conclusion, the cerebral and cerebellar to TBV volume fractions can be important tools in determining brain atrophy and can be estimated by the stereological method.

Stereological evaluation of volumetric asymmetry in healthy human cerebellum.

OBJECTIVES: Age-related volumetric differences in brain anatomy or volumetric brain analyses in many disorders are of interest. Delineating the normal anatomical cerebellar volume is of importance for both the anatomists and clinicians. In the present study, we aimed to evaluate the cerebellar volume using a stereological technique and to determine the possible volumetric asymmetry depending on age and gender. MATERIALS AND METHODS: Volumetric asymmetry of cerebellar hemispheres was evaluated using stereological method on the magnetic resonance images (MRI) of healthy male and female subjects. Randomly selected individuals (27 males, 27 females) aged between 10-86 years who have normal brain MRI were enclosed in the study. All the subjects were right handed. The individuals were divided into three groups according to age as 18-34 (young), 35-60 (middle aged) and 60-84 (elder) and their MRI images were analyzed. The data set were analyzed by two factor repeated measure analysis. RESULTS: Although the cerebellum was smaller between young and middle aged groups and also middle aged and elder groups, there were no any statistically significant differences between compared groups' mean (P > 0.05). There were not statistically differences according to sex and age groups (P > 0.05). CONCLUSIONS: There was no cerebellar asymmetry between compared groups. The stereological evaluation of cerebellar asymmetry in humans correlate with both gender and age groups is of importance for both clinicians and anatomists. The technique is simple, reliable, unbiased and inexpensive.

DUPLICATE PUBLICATION: Comparison of entropy and bispectral index values during propofol induction.

OBJECTIVE: To identify the entropy levels that would correspond to bispectral index (BIS) levels in general anesthesia (GA) induction in patients who will undergo elective lumbar disc surgery (LDS). METHODS: Thirty cases who underwent LDS under GA were included in our study after obtaining patient consent and approval of the Ethics Committee of Afyon Kocatepe University Medical School, Afyonkarahisar, Turkey, between January 01, 2004 to December 31, 2005. Bispectral index and entropy electrodes were applied at the same time to 30 cases in the study group. In order to assess the level of sedation during anesthesia and recovery, `Observer`s Assessment of Alertness/Sedation` (OAA/S) scale was used. Bispectral index, state-entropy (SE), response-entropy (RE), and OAA/S values were recorded simultaneously. RESULTS: Induction OAA/S scores were in correlation with BIS and entropy values (RE-SE) in 30 cases. A significant difference was found between BIS and entropy induction values (p=0.0398). Induction mean arterial pressure and heart rate values at 30, 60, 90, and 120 seconds were lower than the values of the control, which was statistically significant (p=0.0412). CONCLUSION: During the induction of GA, we found entropy values to be more sensitive and they demonstrated a more rapid increase than BIS. Therefore, it would be safer to monitor entropy while using agents of induction that might cause severe hypotension. Induction agents that might cause severe hypotension could be more safely administered under entropy monitoring.

Notice of Duplicate Publication in: Neurosciences 2009; Vol. 14 (1): 106.

Which is more effective in reducing secondary brain damage resulting from cyclooxygenase expression following traumatic brain injury: calcium channel blockers or cox inhibitors?

OBJECTIVES: To evaluate localizations of cyclooxygenase (COX)-1 and COX-2 following traumatic brain injury (TBI) and the effects of 2 therapeutic agents on COX inhibition. METHODS: Forty rabbits were used in this study for developing a TBI model and divided into 4 groups (n=10) at Afyon Kocatepe University School of Medicine, Afyonkarahisar, Turkey in June 2004. Differential cellular COX-1 and COX-2 protein expression profiles were analyzed following TBI, and the effects of 2 therapeutic agents, indomethacin and nimodipine, on COX inhibition were evaluated immunohistochemically. RESULTS: This study revealed that COX-1 and COX-2 protein expression were significantly increased in vascular endothelial, smooth muscle cells, and CD68+ microglia/macrophages following TBI. Indomethacin inhibited the COX expression in glial cells more than nimodipine, however, both did not affect endothelial COX-1 and COX-2 expression. CONCLUSION: The restricted accumulation of COX-1 at the perilesional area points to an acute inflammatory response and the role of COX-1 in TBI. This study revealed that COX-1 expression should be a pharmacological target following TBI, and COX-2 should also be evaluated in this aspect, and indomethacin is more effective than nimodipine for blocking COX-1.

Comparison of unilateral posterior lumbar interbody fusion and bilateral posterior interbody fusion with simple discectomy at degenerative disc herniations.

OBJECTIVES: To evaluate the early results of unilateral posterior lumbar interbody fusion technique in lumbar discectomy cases compared with simple discectomy and bilateral posterior interbody fusion cases using visual analog scale (VAS) and Oswestry outcomes instruments and radiological and physical examinations. METHODS: The control group had 40 patients who underwent simple discectomy. In group one, 8 patients had recurrent disc herniations and facet joint hypertrophy, 21 patients had degenerative disc disease and facet joint hypertrophy. In this group polyetheretherketone (PEEK) cage was used for protecting the disc height and recurrence. In group 2, 15 patients had degenerative lumbar disc herniations and bilateral facet joint hypertrophy. All patients were operated upon between October 2002 between February 2004 at the Neurosurgery Department of Kocatepe University Medical School, and were followed by the help of radiological exams, VAS and Oswestry scores, and clinical exams. The groups were compared to each other statistically. RESULTS: In the control group (n=40) there were recurrences and disc height loss. In group one (n=29) there were no recurrences and the height lost was limited. In group 2, (n=15) there was no recurrence, however, the lost disc height was more than group one. CONCLUSION: If the patient has degenerative disc disease, the use of unilateral posterior PEEK cage and interbody grafting is a safer mode of treatment after discectomy.

Is age a prognostic factor of postoperative outcome of lumbar disc herniation operations?

OBJECTIVE: To evaluate the influence of the patients age on preoperative symptoms and outcome. METHODS: The general data, symptoms, signs, and neurological examination findings were recorded from 511 patients between 2000 and 2006 at Vakif Gureba Hospital and Afyon Kocatepe University Neurosurgery Departments, Afyonkarahisar, Turkey. The mean follow-up of the patients was 44.7 months. All patients younger than 64 were defined as younger patients (n=449). The others were defined as elderly patients (n=62). The measuring method of the outcome was visual analogue rating scale (VAS). RESULTS: Preoperative and postoperative VAS values were found similar in both the younger and older group. Only preoperative differences were found in the older group, due to systemic disease. CONCLUSION: The outcome was not statistically different in both groups, indicating that age is not a valuable prognostic factor for lumbar discectomy.