Evaluating the brainstem in children with breath-holding spells.

OBJECTIVE: Breath-holding spells (BHSs) are a non-epileptic paroxysmal phenomenon characterized by frequent apnea episodes, loss of consciousness, and changes in skin tone and postural tone triggered by negative stimuli of childhood. The pathophysiology of the disease remains unclear; autonomic dysregulation caused by delayed myelination is believed to play a role. In this study, we aimed to evaluate the brainstems of children with BHS using diffusion tensor imaging (DTI) and investigate the etiology of this phenomenon. METHODS: The study group consisted of 16 children with a history of severe breath-holding episodes (accompanied by loss of consciousness and tonic contraction due to prolonged anoxic response) and 18 age-, gender-, and handedness-matched controls. All children underwent systemic, neurologic, and cardiologic evaluation, including complete blood count, blood biochemistry, serum iron and ferritin level, serum vitamin B12 level, electrocardiogram, and electroencephalograms. Magnetic resonance imaging was performed using a 1.5-Tesla Siemens Aera scanner (Siemens, Germany). RESULTS: Evaluation of brainstem (midbrain, pons, and medulla oblongata) volumes revealed no statistically significant differences between the BHS patient and control groups. In a voxel-wise analysis of DTI data, the BHS patient group had significantly lower fractional anisotropy (FA) values than the control group in the bilateral midbrain and medulla, right corticospinal tract, bilateral corpus callosum body and splenium, and left corpus callosum genu. In contrast, there were no significant differences in FA values in the pons, cerebellum, left corticospinal tract, and right corpus callosum genu. CONCLUSION: Based on our findings, we think that patients with BHS should be treated with an approach similar to other neurodevelopmental diseases and that this study may help elucidate the pathophysiology and establish the groundwork for future studies on its treatment.

Diffusion tensor and volumetric magnetic resonance imaging findings in the brains of professional musicians.

Professional musicians represent an ideal model to study the training-induced brain plasticity. The current study aimed to investigate the brain volume and diffusion characteristics of musicians using structural magnetic resonance and diffusion tensor imaging (DTI). The combined use of volumetric and diffusion methods in studying musician brain has not been done in literature. Our study group consisted of seven male musicians playing an instrument and seven age- and gender-matched non-musicians. We evaluated the volumes of gray matter (GM), white matter (WM), and cerebrospinal fluid (CSF) and calculated total intracranial volume (TIV) and measured the fractional anisotropy (FA) of pre-selected WM bundles: corpus callosum (CC), corticospinal tract (CST), superior longitudinal fasciculus (SLF), forceps major (ForMaj), forceps minor (ForMin), and arcuate fasciculus (AF). The mean WM/TIV volume in musicians was higher compared to non-musicians. The mean FA was lower in CC, SLF, ForMaj, ForMin, and right AF but higher in right CST in the musicians. The mean value of the total number of fibers was larger in the CST, SLF, left AF, and ForMaj in the musicians. The observed differences were not statistically significant between the groups (p>0.05). However, increased GM volume was found in the musicians compared to the non-musicians in the right and left cerebellum and supramarginal and angular gyrus, left superior and inferior parietal lobule and as well as left middle temporal gyrus. Our findings suggest differing brain structure in musicians and the confirmation of the results on a larger population.

The intracranial and posterior cranial fossa volumes and volume fractions in children: a stereological study / Los volúmenes de la fosa craneal intracraneal y posterior y las fracciones de volumen en los niños: un estudio estereológico

SUMMARY: The size of intracranial cavity (IC) and posterior cranial fossa (PCF) plays an important role in the pathophysiology of various disorders. In this study, we aimed at establishing normal volume data of the IC and PCF in Turkish population according to age and sex by using stereological method. This study was carried out retrospectively on 339 individuals (168 females and 171 males) between 0 and 18 years old with no medical or neurological disorders that affected the skeletal morphology of the cranial cavity. Volumetric estimations were determined on computed tomography (CT) images using point-counting approach of stereological methods. Intracranial volume (ICV) and posterior cranial fossa volume (PCFV) were increased with age in both sexes. They reached adult dimensions at 5 years of age during the teenage years. According to sex; the mean ICV and PCFV were 1594.51±245.57cm3 and 244.89±53.86 cm3 in males, 1456.34±241.85 cm3 and 228.24±41.38 cm3 in females, respectively. Generally, significant differences were determined in ICV and PCFV according to sex after they reached maximum growth period. According to age the volume ratios of PCF to IC was ranged from 13.03 to 17.48 in males and 12.06 to 18.54 in females. This study demonstrated that these volume ratios could help the physician for both patient selections for surgery, and for the assessment of any surgical technique used to treatment of PCF malformations. However current study revealed that point counting method can produce accurate volume estimations and is effective in determining volume estimation of IC and PCF.

RESUMEN: El tamaño de la cavidad intracraneal (CI) y la fosa craneal posterior (FCP) desempeñan un papel importante en la fisiopatología de diversos trastornos. En este estudio, se pretende establecer los datos de volumen normal de la CI y FCP en la población turca, de acuerdo a la edad y el sexo, mediante el uso de métodos estereológicos. Este estudio se realizó retrospectivamente en 339 individuos (168 mujeres y 171 hombres) entre 0 y 18 años sin trastornos médicos o neurológicos que afectaron la morfología esquelética de la cavidad craneal. Las estimaciones volumétricas se determinaron en imágenes de tomografía computarizada (TC) utilizando el conteo de puntos de los métodos estereológicos. El volumen intracraneal (VIC) y el volumen posterior de la fosa craneal (VFCP) aumentaron con la edad en ambos sexos. Alcanzaron dimensiones adultas a los 5 años de edad durante la adolescencia. Según el sexo, el promedio de VIC y VFCP fue de 1594,51 ± 245,57 cm3 y de 244,89 ± 53,86 cm3 en los hombres, 1456,34 ± 241,85 cm3 y 228,24 ± 41,38 cm3 en las mujeres, respectivamente. En general, se determinaron diferencias significativas en VIC y VFCP de acuerdo con el sexo después de alcanzar el período de crecimiento máximo. Según la edad, las proporciones de volumen de FCP a CI oscilaban entre 13,03 a 17,48 en los hombres y 12,06 a 18,54 en las mujeres. Este estudio demostró que estas proporciones de volumen podrían ayudar al médico tanto en la selección de pacientes para la cirugía, como para la evaluación de cualquier técnica quirúrgica utilizada en el tratamiento de malformaciones de FCP. Además, el estudio actual reveló que el método de conteo de puntos puede producir estimaciones precisas de volumen siendo eficaz para determinar la estimación de volumen de IC y FCP.

Palatine tonsil volume estimation using different methods after tonsillectomy.

This study was carried out to measure the volume of the palatine tonsil in otorhinolaryngology outpatients with complaints of adenotonsillar hypertrophy and chronic tonsillitis who had undergone tonsillectomy. To date, no study has investigated palatine tonsil volume using different methods and compared with subjective tonsil size in the literature. For this purpose, we used three different methods to measure palatine tonsil volume. The correlation of each parameter with tonsil size was assessed. After tonsillectomy, palatine tonsil volume was measured by Archimedes, Cavalieri and Ellipsoid methods. Mean right-left palatine tonsil volumes were calculated as 2.63 ± 1.34 cm3 and 2.72 ± 1.51 cm3 by the Archimedes method, 3.51 ± 1.48 cm3 and 3.37 ± 1.36 cm3 by the Cavalieri method, and 2.22 ± 1.22 cm3 and 2.29 ± 1.42 cm3 by the Ellipsoid method, respectively. Excellent agreement was found among the three methods of measuring volumetric techniques according to Bland-Altman plots. In addition, tonsil grade was correlated significantly with tonsil volume.

Characterization of tympanic cavity volume in newborns using computerized tomography scanning / Caracterización del volumen de la cavidad timpánica en recién nacidos usando tomografía computadorizada

This study reports tympanic cavity (TC) volume in newborns, which was missing in the literature. Ex vivo histology and computerized tomography (CT) scans were performed on temporal bone and data were analyzed in part using software developed in house. CT images with a slice thickness of 0.5 mm were obtained from 5 newborn cadavers and analyzed independently by two expert researchers. The border of the TC was delineated manually and measurement of area of interest was calculated on masked images. Then, the area measurements from all sections were added to estimate the total volume. The agreements between the histological and CT findings were then compared for accuracy, repeatability and reliability. The Dice and Jaccard similarity coefficient measures were used as a statistical validation metric to evaluate the assessor's performance in manual volume segmentation. Good assessor agreement was observed with average Dice values above 0.8 indicating that consistent and reliable volume measurements were feasible. The proposed protocol was shown to be accurate in calculating the TC volume, and thus can be used for computer-assisted presurgical planning or for diagnosing structural alterations in TC.

El objetivo fue determinar el volumen de la cavidad timpánica (CT) en recién nacidos, información no encontrada en la literatura. Se realizaron escaners a través de tomografia computadorizada (TC) y estudios histológicos en el hueso temporal; los datos se analizaron utilizando un software desarrollado en nuestra institución. Se obtuvieron imágenes de secciones de TC, de 0,5 mm de grosor, a partir de 5 cadáveres de recién nacidos, los que fueron analizados de forma independiente por dos investigadores expertos. El margen de los cortes de TC fue delineado manualmente y la medición del área de interés se estimó sobre imágenes ocultas. Después, se añadieron las mediciones de área de todas las secciones para estimar el volumen total. Las concordancias entre el estudio histológico y los hallazgos de la TC se compararon en cuanto a precisión, repetibilidad y confiabilidad. Se utilizaron las medidas de coeficiente de similitud de Jaccard y Dice como métrica de validación estadística para evaluar el desempeño del asesor en la medición manual del volumen. Se observó una buena correlación del evaluador con los valores medios de Dice, por encima de 0,8 indicando que es factible obtener mediciones coherentes y confiables de volumen. El protocolo propuesto ha demostrado ser preciso para calcular el volumen de la CT, y por lo tanto se puede utilizar para la planificación prequirúrgica asistida o para el diagnóstico de alteraciones estructurales en la CT.

The rate of device-associated nosocomial infections in a medical surgical intensive care unit of a training and research hospital in Turkey: one-year outcomes.

In the present study, we aimed to assess the rate and effect of device-associated nosocomial infections (DANIs), as well as the rate of antibiotic resistance, in the medical-surgical intensive care unit (ICU) of a research and training hospital in Turkey, and to compare our results with those reported by the National Nosocomial Infections Surveillance (NNIS) system and International Nosocomial Infection Control Consortium (INICC). A total of 509 patients were followed up within a 1-year period from 1 November 2007 to 1 November 2008. The total patient days were 4,087, the number of DANIs was 181. The ventilator-associated pneumonia rate in 1,000 ventilator days was 27.1, the rate of central venous catheter (CVC)-associated blood circulation infections in 1,000 CVC days was 11.8, and the rate of urinary catheter-associated urinary tract infections in 1,000 urinary catheter days was 9.6. The most frequently isolated microorganisms were Pseudomonas aeruginosa and Acinetobacter spp. Of the infections caused by Staphylococcus aureus, 81.2% were due to methicillin-resistant strains. Of the Enterobacteriaceae isolates, 53.5% were found to be resistant to ceftriaxone, while 29% of the P. aeruginosa isolates were found to be resistant to ciprofloxacin. The rates of use of devices such as ventilators, CVCs, and urinary catheters were 0.87, 0.93, and 0.98, respectively, which are higher than the rates reported by NNIS and INICC. On the other hand, the present DANI rate was higher than that reported by NNIS, but close to that reported by INICC. We conclude that the indications for and duration of device use should be reviewed.