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Kader Karli Oguz

Publications and source records attributed to Kader Karli Oguz.

17 recordsLinked to original sources
PubMed2007

Widening the spectrum of PRES: series from a tertiary care center.

Posterior reversible encephalopathy syndrome (PRES) has been defined as a neurologic disorder with distinct radiologic findings demonstrating lesions in the subcortical white matter at posterior circulation territory. Several authors suggested alternative descriptive terms for this syndrome as atypical radiologic features have been described more frequently. In this retrospective study, we sought to determine the frequency and features of radiologic findings in the setting of a tertiary care center. We also noticed that some of our patients had simultaneous multiple conditions that were previously shown to cause PRES independently in the literature. These probable predisposing factors were also revisited.

Adolescent↗
PubMed2006

MR imaging, diffusion-weighted imaging and MR spectroscopy findings in acute rapidly progressive subacute sclerosing panencephalitis.

We are presenting two cases with subacute sclerosing panencephalitis of acute and rapid form, which were initially diagnosed as acute viral encephalitis. We obtained both diffusion-weighted imaging and magnetic resonance spectroscopy, whose findings suggested the presence of acute inflammatory and metabolic changes with peculiar distribution, which were not observed on conventional MR imaging. These techniques might help to demonstrate the extent and progression of the panencephalitis.

Anticonvulsants↗
PubMed2006

Hippocampal atrophy correlates with the severity of cognitive decline.

BACKGROUND: The aim of this study is to compare the results of magnetic resonance (MR) imaging, particularly the decline in hippocampal volume, of patients with Alzheimer's disease (AD) and mild cognitive impairment (MCI) with healthy age-matched controls, to examine the reliability of hippocampal volumetry in the early diagnosis of AD and the correlation of the severity of hippocampal atrophy with the severity of cognitive decline. METHODS: Twenty-six AD, 22 MCI and 15 normal cognitive status (NCS) patients were scanned with a 3 Tesla MR scanner. Hippocampus volumes were detected manually by Osiris 4.18. RESULTS: Multivariate regression analysis, which was performed to adjust the covariate effects of education, age, gender, hypertension and diabetes mellitus, showed that hippocampal atrophy was correlated with AD and MCI for right hippocampus; AD, MCI and age for left hippocampus independent of other parameters. A second regression analysis revealed that MMSE was correlated with hippocampal volume. CONCLUSIONS: Hippocampal volumetry can be used in early diagnosis of cognitive impairment, as well as grading cognitive decline.

Aged↗
PubMed2006

Atypical clinical course in juvenile metachromatic leukodystrophy involving novel arylsulfatase A gene mutations.

A male and female with juvenile metachromatic leukodystrophy (MLD) with unusual manifestations are presented, each involving a novel arylsulfatase A gene mutation. One patient demonstrated acute intermittent encephalopathic episodes for 1 year after having received the diagnosis of MLD at the age of 6 years. The other patient presented at the age of 5 years with acute hemiparesis, which was diagnosed as acute disseminated encephalomyelitis and resolved in 3 weeks. After 2 years of remission he started to show progressive neurological deterioration. The episodic manifestations in both patients were associated with acute, resolving cerebral lesions on magnetic resonance imaging accompanying or preceding the classical demyelinating lesions of MLD. The diagnosis of MLD was based on arylsulfatase A enzyme activity levels and genetic analysis, and after the exclusion of neurological conditions such as encephalitis, vasculopathy, or mitochondrial disorders. The pathogenesis of this previously undescribed finding in MLD is unknown but might be related to a susceptibility of myelin to acute damage.

Acyclovir↗
PubMed2005

Streptococcus oralis as a risk factor for middle cerebral artery thrombosis.

We reported a case of an 8-year-old boy who was presented to the emergency department with left-sided hemiparesis. Computed tomography showed hypodense areas in the territory of the right middle cerebral artery, indicating acute cerebral infarct. Diagnostic evaluation was performed to identify the etiology. On the eighteenth day of hospitalization, cerebrospinal fluid cultures yielded Streptococcus oralis. We hypothesized that the source of the oral pathogen was an abscess belonging to his upper left fourth tooth, which, by a transient bacteremia, had invaded the central nervous system, and skipping the meninges caused local inflammatory arteritis of the carotid artery, leading to cerebral infarction. Sulbactam-ampicillin therapy was initiated for 14 days, and he was discharged with anticoagulation therapy.

Child↗
PubMed2005

Reversible posterior leukoencephalopathy syndrome: report of three cases.

Reversible posterior leukoencephalopathy syndrome is characterized clinically by headache, abnormalities of mental status and visual perception, and seizures. Despite its diverse causes, common precipitating factors are defined as abrupt elevations of blood pressure, renal decompensation, fluid retention, and immunosuppressive therapy. We report three children with reversible posterior leukoencephalopathy syndrome presenting with generalized seizures and headache. The causes of reversible posterior leukoencephalopathy syndrome were considered to be acute hypertension and immunosuppressive therapy in case 1 with systemic lupus erythematosus, chemotherapy (vincristine and/or actinomycin-D) and hyponatremia in case 2, and acute hypertension in case 3, admitted with a familial Mediterranean fever attack. In light of these cases, we review the literature for the etiology, clinical and laboratory findings, and pathogenetic mechanisms of the disease.

Adolescent↗
PubMed2004

Epileptic nystagmus in a patient with nonconvulsive status epilepticus.

Epileptic nystagmus (EN) is a rare form of rhythmic eye oscillations occurring during seizure activity. Not only convulsive states, but also nonconvulsive status may represent with EN and this phenomenon may be the only motor manifestation of seizure activity. Epileptic activation of a cortical saccade region may be distinguished from activation of a cortical pursuit region clinically as activation of pursuit regions results in nystagmus slow phases that bring the eyes across the midline. Horizontal EN results most commonly from seizure activity involving the occipital cortex. In this report, horizontal EN in a patient with nonconvulsive status epilepticus (NCSE) is described with clinical, radiological and electrophysiological findings that occur probably due to posterior leukoencephalopathy syndrome.

Brain↗
PubMed2003

Diffuse spinal and intercostal nerve involvement in chronic inflammatory demyelinating polyradiculoneuropathy: MRI findings.

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is an uncommon demyelinating disorder with a relapsing and remitting or continuously progressive course. Hypertrophic nerve roots, sometimes associated with gadolinium enhancement, has been reported more commonly in lumbar spine and less commonly in the brachial plexus and cervical roots; however, diffuse involvement of intercostal nerves bilaterally has never been reported previously. We present MRI findings which include diffuse enlargement and mild enhancement of roots and extraforaminal segments of nerves in all segments except a short segment between T12-L2 as well as all the intercostal nerves in a case of CIPD with a 10-year history.

Biopsy, Needle↗
PubMed2003

Neuroradiological findings in a mother and daughter with Gorlin syndrome.

A mother and daughter with Gorlin syndrome with similar neuroradiological findings are reported. These include calcification of the falx cerebri and tentorium cerebelli and dysgenesis of the corpus callosum and vermis. Vermian dysgenesis was detected in both mother and daughter suggesting a previously unrecognized finding associated with Gorlin syndrome.

Adolescent↗
PubMed2003

Correlation of functional MR imaging activation data with simple reaction times.

PURPOSE: To determine the relationship between subject reaction times (RTs) and activation volume in the brain during visuomotor functional magnetic resonance (MR) imaging. MATERIALS AND METHODS: Twenty-four subjects performed a simple RT task during single-event functional MR imaging, and RTs were recorded. The six subjects with the fastest RTs were designated the fast RT group, and the six subjects with the slowest RTs were designated the slow RT group. The data were processed with noncorrected height threshold (P <.001) for individual comparisons and corrected height threshold (P <.05) for group comparisons (t tests). The activation volumes in both occipital lobes, the left sensorimotor cortex, and the supplemental motor cortices were compared for the two groups. RESULTS: The mean RT +/- SD was 342 msec +/- 20.15 for the fast RT group and 475 msec +/- 36.17 for the slow RT group (P <.0001). More voxels of activation were seen in the fast RT group than in the slow RT group in the occipital lobes, left sensorimotor cortices, and supplemental motor cortices on individual and group maps. This difference was statistically significant in the left sensorimotor (P =.03) and left visual (P =.05) cortices. In the right visual cortex, a trend toward more activation in the fast RT group was noted (P =.15). There was a negative correlation between RTs and activation volume in the left sensorimotor cortex (P =.048). CONCLUSION: There was a greater activation volume in motor and visual cortices in the fast RT group than in the slow RT group.

Adult↗
PubMed2003

Lack of sex effect on brain activity during a visuomotor response task: functional MR imaging study.

BACKGROUND AND PURPOSE: As more individuals are enrolled in clinical functional MR imaging (fMRI) studies, an understanding of how sex may influence fMRI-measured brain activation is critical. METHODS: We used fixed- and random-effects models to study the influence of sex on fMRI patterns of brain activation during a simple visuomotor reaction time task in the group of 26 age-matched men and women. We evaluated the right visual, left visual, left primary motor, left supplementary motor, and left anterior cingulate areas. RESULTS: Volumes of activations did not significantly differ between the groups in any defined regions. Analysis of variance failed to show any significant correlations between sex and volumes of brain activation in any location studied. Mean percentage signal-intensity changes for all locations were similar between men and women. A two-way t test of brain activation in men and women, performed as a part of random-effects modeling, showed no significant difference at any site. CONCLUSION: Our results suggest that sex seems to have little influence on fMRI brain activation when we compared performance on the simple reaction-time task. The need to control for sex effects is not critical in the analysis of this task with fMRI.

Adult↗
PubMed2002

Correlation of reaction time in and out of the functional MR unit.

RATIONALE AND OBJECTIVES: The authors performed this study to determine whether reaction times (RTs) recorded in the functional magnetic resonance (MR) imaging environment reflect the performance of the patient outside the imaging room. MATERIALS AND METHODS: Fifteen healthy control subjects (mean age, 61.6 years) performed a simple reaction time (SRT) task outside the MR magnet and a visuomotor response time task inside the magnet with use of block-design and event-related paradigms. For both behavioral and functional MR imaging tests, subjects tapped the right index finger upon the appearance of a visual cue. The mean RTs for out-of-magnet and functional MR imaging paradigms were compared. Results. There was a statistically significant difference in RTs between block-design and single-event paradigms (t = 3.458, P < .004). The RT values during functional MR imaging and SRT tasks did not show significant differences (.65 < P < .7, paired t test). However, no correlation was found in RT values between event-related (p = -0.004, P = .15) or block-design (p = 0.03, P = .13) paradigms and SRT data. With the block-design functional MR imaging paradigm, the RT was significantly faster (P < .0003) at the beginning of the session than the end, illustrating the effect of anticipation. CONCLUSION: Functional MR imaging RTs must be used to determine the correlation between subjects' performance and the volume of brain activation in a functional MR imaging experiment. The effect of anticipation should be minimized, which could best be achieved by using event-related paradigms.

Adult↗
PubMed2002

Impact of pager notification on report verification times.

RATIONALE AND OBJECTIVES: The purpose of this study was to assess the impact on times of verification (TOVs) by a pager notification system (PNS) that informs physicians when reports are available for signature. MATERIALS AND METHODS: An automated PNS was implemented in the authors' department in November 2000. Monthly report verification times of each physician were collected for 3 months in the years before and after initiation of the PNS. Radiologists enrolled in the PNS and those who were not were assigned into two groups for analysis. Mean TOVs for the two sets of 3 months and for the two groups were calculated and differences recorded. Two-tailed t tests were used to assess for statistical differences between the groups. RESULTS: Twenty-nine of 37 radiologists voluntarily enrolled in the PNS (group 1). Mean TOV was 26.75 hours (standard deviation [SD] = 17.76) for these physicians before and 14.48 hours (SD = 11.86) after the PNS was employed (P < .01). For those physicians who did not enroll in the PNS, mean TOV was 11.53 hours (SD = 5.55) before and 9.77 hours (SD = 9.86) after the PNS was employed (P = .33). Both the absolute and percentage reductions in TOVs were significantly greater for those physicians enrolled in the PNS than for those who were not (P = .035). Twenty-three of 29 (79%) physicians who used the PNS showed a reduction in their report turnaround times. CONCLUSION: Linking the PNS with the radiology information system to notify physicians of unsigned reports was effective in reducing report verification times.

Humans↗
PubMed2002

Effect of emergency department CT on neuroimaging case volume and positive scan rates.

RATIONALE AND OBJECTIVES: The authors performed this study to determine the effect a computed tomographic (CT) scanner in the emergency department (ED) has on neuroimaging case volume and positive scan rates. MATERIALS AND METHODS: The total numbers of ED visits and neuroradiology CT scans requested from the ED were recorded for 1998 and 2000, the years before and after the installation of a CT unit in the ED. For each examination type (brain, face, cervical spine), studies were graded for major findings (those that affected patient care), minor findings, and normal findings. The CT utilization rates and positive study rates were compared for each type of study performed for both years. RESULTS: There was a statistically significant increase in the utilization rate after installation of the CT unit (P < .001). The fractions of studies with major findings, minor findings, and normal findings changed significantly after installation of the CT unit for facial examinations (P = .002) but not for brain (P = .12) or cervical spine (P = .24) examinations. In all types of studies, the percentage of normal examinations increased. In toto, there was a significant decrease in the positive scan rate after installation of the CT scanner (P = .004). CONCLUSION: After installation of a CT scanner in the ED, there was increased utilization and a decreased rate of positive neuroradiologic examinations, the latter primarily due to lower positive rates for facial CT scans.

Cervical Vertebrae↗
PubMed2002

Cervical diastematomyelia in cervico-oculo-acoustic (Wildervanck) syndrome: MRI findings.

Cervico-oculo-acoustic (COA) or Wildervanck syndrome is characterized by the triad of Klippel-Feil anomaly, bilateral abducens palsy with retracted bulbs (Duane 'syndrome') and hearing loss. The clinical findings of this syndrome have been well documented. A few case reports with MRI findings have appeared in the literature showing brainstem and cerebellar hypoplasia and vertebral segmentation anomalies. Our case is unique in that diastematomyelia of the lower medulla and cervical cord was accompanied by vermian hypoplasia, tonsillar herniation and resulting triventricular hydrocephalus in a child with Wildervanck syndrome. This case is presented with MR images. Children with Wildervanck syndrome should be investigated for craniospinal abnormalities with MR imaging.

Child, Preschool↗
PubMed2001

Multifocal fibrosclerosis: a new case report and review of the literature.

A case of multifocal fibrosclerosis is presented with MR images. Bilateral sclerosing orbital pseudotumor invading cavernous sinuses were the presenting disorder. Magnetic resonance imaging showed involvement of paranasal sinuses bilaterally and multiple supratentorial dural masses. Retroperitoneal fibrosis was associated with the condition. Multifocal involvement should be considered in patients with sclerosing orbital pseudotumor and an imaging approach should be performed on the appropriate clinical condition to document possible coexistence of other disorders including retroperitoneal fibrosis, mediastinal fibrosis, sclerosing cholangitis, and Riedel's thyroiditis

Adult↗