Physiological noise in MR images: An indicator of the tissue response to ischemia?

PURPOSE: To determine whether measuring signal intensity (SI) fluctuations in MRI time series data from acute stroke patients would identify ischemic tissue. MATERIALS AND METHODS: Prebolus perfusion-weighted MRI data from 32 acute ischemic stroke patients (N = 32) was analyzed as a time series. Ischemic and normal tissue regions were outlined and compared. RESULTS: The magnitude of the measured SI fluctuations was significantly lower in ischemic regions relative to normal tissue. Spatial differences in these fluctuations occurred in a manner that was different than other perfusion-based metrics. CONCLUSION: Prior studies have shown that SI fluctuations in MRI time series data correspond to the presence of physiological "noise," which includes vasomotion, an autoregulatory phenomenon that affects the tissue response to ischemia. In this study, SI fluctuations were found to decrease in ischemia, consistent with the notion that small vessels will remain open (fluctuations in vessel diameter will decrease) when there is a challenge to flow. Spatial variation in SI fluctuations appeared to be different from spatial variation seen on other perfusion-based metrics, suggesting that a separate contrast mechanism is responsible, one that might be of diagnostic and prognostic value in acute stroke in which the ability of tissue to withstand ischemia is currently not well visualized.     

Incidence of auditory neuropathy among the deaf school students

OBJECTIVE: We aimed to determine the incidence of auditory neuropathy (AN) among the deaf school students that have severe hearing loss. METHOD: All students having severe hearing loss constituting a total of 75 at Deafness school in Afyon Province of Turkey were enrolled in the study. The etiological factors about the hearing loss were determined by performing an individual file survey and by interviewing the teachers and parents. First, all the children were subjected to an otolaryngologic examination. Then, auditory brainstem response (ABR) and transient evoked otoacoustic emissions (TEOAE) tests were done to all students enrolled in the study. RESULTS: The ages of the children were between 6 and 17 (mean age 11.9) and 32 (42.9%) of them were girls and 43 (57.1%) were boys. Three cases (4%) were diagnosed as AN in our study, however, no risk factors were determined in two of them. A history of hearing loss following a vaccination was found in only one patient. CONCLUSION: Our data show that the incidence of AN in the children with severe hearing loss is not negligible. Therefore, our results suggest that automatic ABR should be also used with OAE as a routine application in the neonatal screening programmes, since the solely use of OAE in the neonatal screening programmes may result in the delay of the diagnosis of the children with AN.     

Assessment of tetrahydrobiopterin responsiveness in Turkish hyperphenylalaninemic patients

Tetrahydrobiopterin (BH4) therapy is the latest alternative approach in phenylalanine hydroxylase (PAH) deficiency, and is suggested for a number of hyperphenylalaninemic (HPA) patients with certain mutations. In our unit, therapeutic efficacy of BH4 was evaluated in 20 HPA patients (4 mild HPA, 9 mild phenylketonuria-PKU, 7 moderate PKU) by a single oral dose of BH4. Overall, 60% of the patients responded (45% favorably, 15% partially). All of the mild HPA patients and 55% of mild PKU patients responded to BH4 favorably and an additional 11% of mild PKU patients responded partially. Of 7 moderate PKU patients, 2 responded partially (28%). The genotypes of the patients who responded to BH4 favorably were: DelF39/-, L48S/L48S, R261Q/- (4 patients), A300S/IVS2nt5g > c, A300S/-, E390G/E390G. The genotypes of the patients who exhibited a partial response were: L48S/L48S, R261Q/ R261Q, IVS10nt546/-. We concluded that since there are too many mutations and many patients are compound heterozygote, it is difficult to predict BH4 responsiveness based solely on genotype, especially for the mutations which show inconsistent phenotypes. The best way to identify the patients who are more likely to benefit from BH4 administration is performing BH4 loading test. Long-term BH4 loading test should be performed in classical and moderate PKU patients to confirm that they are not responsive to BH4.     

Lipofibromatosis in a two-year-old girl: a case report

Lipofibromatosis is a recently described rare benign soft tissue tumor of childhood. We report a case of a lipofibromatosis in a two-year-old girl with a painless mass on the plantar aspect of her right foot who developed local recurrence eight months after surgery. The tumor has a high rate of non-destructive recurrence, but there is no metastatic potential. Complete surgical resection is the mainstay of treatment. Nevertheless, the rareness of its presentation should be taken into account by the pediatric pathologist, and considerable surgical judgment is of great importance.     

Fluvastatin reduced liver injury in rat model of extrahepatic cholestasis

Inhibitors of 3-hydroxy-3methylglutarly coenzyme A, reductase, namely statins, exert pleiotropic actions beyond lipid-lowering effects. In ex vivo and in vitro studies, statins have antioxidative and antiinflammatory effects. Herein, we sought to determine whether treatment with fluvastatin (FV) would be beneficial in a rat model of common bile duct ligation (BDL)-induced liver injury. Female rats were subjected to a sham (n = 10) or BDL (n = 20). Obstructive jaundice was induced in rats by the ligation and division of the common bile duct. Three days after operation, rats subjected to CBDL were randomized to receive treatment with either FV (10 mg/kg) or saline every day over a 10 days experimental period. High levels of alanine aminotransferase, aspartate aminotransferase, and gamma glutamyltransferase decreased significantly (P < 0.05) in animals treated with FV with compared to saline-administrated BDL animals. Compared with sham-operated rats, CBDL rats showed significantly higher levels of total nitrite and nitrate, malondihaldehyde, tumor necrosis factor alpha, myeloperoxidase, and lower concentrations of glutathione, superoxide dismutase, and catalase in the liver tissue (P < 0.001). All of these changes were significantly attenuated (P < 0.05) by treatment with FV after CBDL. CBDL was associated with increased apoptosis and nuclear factor kappa beta expression in saline-treated rats. Treatment with FV also decreased these parameters. These data support the view that FV ameliorates hepatic inflammation, lipid peroxidation, and tissue injury in rats subjected to CDBL. FV warrants further evaluation as an adjunctive treatment to ameliorate liver injury from extrahepatic biliary obstruction.     

The mucocutaneous manifestations associated with celiac disease in childhood and adolescence

This study was performed to detect the prevalence of mucocutaneous manifestations of celiac disease in childhood and adolescence and to investigate the relationship between these findings and duration of disease and a gluten-free diet. The study included 55 children and adolescents with a mean age of 10.0 +/- 4.61 years (2-19 years). Mucocutaneous manifestations were evaluated with respect to age, gender, duration of illness, and of gluten-free diet and compliance with this diet. Cutaneous, mucosal, nail, and hair findings were detected in 74.5%, 27.3%, 20.0%, and 7.3% of patients, respectively. The most prevalent dermatologic diagnosis was xerosis (69.1%). No significant relationship was detected between the cutaneous findings and the duration of illness (p > 0.05). However, the duration was longer in patients with mucosal findings compared to those without mucosal findings (p < 0.05). It was found that all patients without cutaneous findings were on a strict gluten-free diet (p < 0.05). Ours is one of the few studies describing skin findings in children with celiac disease. We believe that both pediatricians and dermatologists should be aware of the various mucocutaneous manifestations of celiac disease, because a careful skin, mucosa, nail, and hair examination may lead to a diagnosis of celiac disease, particularly in atypical presentations.     

Can cerebrospinal fluid uric acid levels differentiate intraventricular hemorrhage from traumatic tap?

OBJECTIVE: To measure blood and cerebrospinal fluid (CSF) uric acid (UA) levels of neonates with intraventricular hemorrhage (IVH), and to examine whether or not UA can be used to differentiate traumatic tap from IVH. MATERIAL AND METHODS: The control group (n = 19, group I) consisted of neonates presenting with signs requiring analysis of CSF but whose CSF indices proved to be normal. Traumatic taps (n = 15, group II) were mimicked by adding 2 drops of homologous blood to normal CSF samples. The IVH group (n = 21, group III) consisted of neonates who had been diagnosed by cranial ultrasonography or computed tomography scans. Data are presented as median (range). RESULTS: There was no significant difference between groups with respect to serum UA levels. While no significant difference was observed between CSF UA levels of the control [0.6 (0.1-1.8) mg/dl] and traumatic tap group [0.5 (0.3-1.1) mg/dl], the IVH group [1.6 (0.7-6.9) mg/dl] was found to have significantly higher CSF UA levels than groups I and II. Furthermore, although there were significant correlations between serum and CSF UA levels in the control and traumatic tap groups, no correlation was observed in the IVH group. CONCLUSION: CSF UA levels are increased in neonates with IVH and they may be used to differentiate a real hemorrhage from a traumatic tap.     

Paratesticular metastasis from Wilms tumor associated with a hydrocele

Metastatic sites other than the lungs, lymph nodes, and liver are unusual for Wilms tumor (WT). Intra-scrotal metastasis is very rare. We report a 3-year-old boy with stage IIA WT, who experienced paratesticular metastasis 2 months after surgery for an abdominal recurrence. He had right scrotal hydrocele at initial diagnosis. The patient underwent right radical orchiectomy, and pathological examination revealed paratesticular WT metastasis. Intra-abdominal and peritoneal disseminated metastases followed. We considered that tumor cells spread through the patent processus vaginalis and grew at paratesticular space in hydrocele. One month after the end of 12 months of salvage chemotherapy and abdominal radiotherapy, the patient has no evidence of disease.