FDG-PET in early infancy: simplified quantification methods to measure cerebral glucose utilization

For further insight into the physiology and pathogenesis of the developing brain, quantification of the cerebral glucose metabolism is needed. Arterial blood sampling or sampling of great volumes of blood is not justified for the purpose of PET studies in children. Therefore, we have developed simplified PET approaches to analyze brain FDG examinations during infancy. METHODS: The study consisted of 18 FDG-PET examinations chosen from our research protocols concerning hypoxicischemic encephalopathy and severe neonatal hypoglycemia. The input function for graphical analysis according to Patlak was derived in two ways: (1) a combined time-activity curve derived from the left ventricular activity concentration (first 7-17 min of the study) and radioactivity concentration in venous whole-blood samples and; (2) activity concentration measured in whole-blood venous blood samples (arterial plasma in one case). As an alternative for semiquantitation, the standardized uptake values (SUV) were calculated and correlated to local cerebral metabolic rates for glucose (LCMRGlc). RESULTS: The influx rate constants (Ki) and LCMRGlc values obtained using the combined curve versus venous curve did not differ statistically (p > 0.05). There was a good correlation between the SUV and LCMRGlc values (r = 0.83, p < 0.001). CONCLUSION: Local cerebral metabolic rates for glucose can be accurately calculated by using the combined curve (left ventricular activity concentration during first 5 min of the study and 2-3 venous whole-blood samples at the end of the study) for even the smallest pediatric patients. When blood samples cannot be obtained, SUV values provide an alternative for estimation of the cerebral glucose uptake and interindividual comparison of the patients.     

Subjective cognitive complaints and longitudinal changes in memory and brain function.

Objective: Subjective cognitive complaints are often used in the diagnosis of memory and other cognitive impairment. This study examined whether cognitive complaints are associated with longitudinal changes in cognition and cross-sectional differences in regional brain function during memory performance in 98 participants with a mean age of 75. Method: The Cognitive Failures Questionnaire (CFQ) assessed cognitive complaints and mixed effects regression models were used to determine whether mean CFQ scores predicted rates of change in cognitive function over a period of 11.5 years. Results: Higher CFQ scores, reflecting increased subjective complaints, were associated with steeper rates of decline in immediate and delayed recall on the California Verbal Learning Test. Voxel-based regression analysis was used to determine the cross-sectional relationship between CFQ scores and regional cerebral blood flow measured by PET during a resting condition and during verbal and figural memory tasks. Higher levels of cognitive complaints were associated with increased activity in insular, lingual and cerebellar areas during memory tasks. Conclusions: These findings offer some support for the validity of subjective cognitive complaints as markers of age related changes in memory and brain activity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Wegener''s granulomatosis presenting as a recurrence of chronic otitis media

INTRODUCTION: Tinnitus is still one of the most frequent symptoms encountered by the otorhinolaryngologist. Diagnosis and therapy present high demands due to the complex etiology and secondary symptoms. PATHOPHYSIOLOGY: In contrast to objective ear ringing with a physical sound source near the ear, tinnitus is faulty coding within the auditory system. Damage due to all kinds of causes can lead to a change of spontaneous activity in the auditory system. The result is a subjective auditory impression which is increased by further learning processes. DIAGNOSTICS: The aim of otorhinolaryngologic and especially audiologic diagnostic studies is to find the cause of the tinnitus. Modern methods for the objectivation of tinnitus are still experimental. The psychosomatic diagnostic studies evaluate secondary symptoms. THERAPY: Acute tinnitus is treated like sudden deafness. For chronic forms, the analysis of the causes is particularly important for developing an individual consultation and therapy plan. Providing information of the patient is the first step for a sensible treatment of the symptoms. The retraining therapy represents a learning process to reduce subjective symptoms, inconvenience, and loudness. Supportive therapy includes the use of instrumentation and medication. CONCLUSION: Acute tinnitus is often curable. However, only palliative treatment is available for chronic tinnitus. The otorhinolaryngologist plays a crucial role in the management of the disorder.     

Nursing knowledge: the role of Plato in wound care

In the field of neuroradiology in particular, a number of special indications have been identified for which the new generation of imaging procedures, MRT and PET are superior to other technologies currently available. This applies, for example, to MRT used to investigate MS, herpes encephalitis, certain forms of epilepsy and arteriovenous anomalies or cavernomas. Further developments of the MRT technique are being used to visualize vascular anomalies or the penumbra in the case of cerebral infarction. Here, MRT is increasingly entering the area of functional imaging which, however, is primarily the domain of PET. For the first time, PET now allows us to objectify such otherwise merely subjective symptoms as chronic pain or tinnitus. In the preoperative diagnosis of epilepsy, for example in the case of temporal lobe epilepsy, PET has now been accepted as the standard technique.     

Audio-vestibular manifestations of Chiari malformation and outcome of surgical decompression: a case report

Sensorineural hearing loss, tinnitus, dizziness and ataxia are recognised symptoms associated with Chiari malformations but they are rarely the presenting complaints. Patients with such symptoms are frequently referred to otolaryngologists and audiological physicians. We report a case of a 13-year-old girl who presented complaining of tinnitus and impaired hearing, and was subsequently diagnosed as having a type I Chiari malformation. Pure tone audiogram showed a mild hearing impairment on the left side and the speech audiogram was normal. Auditory brain stem responses and the electronystagmography were abnormal. The patient underwent posterior fossa decompression following which her tinnitus disappeared, the hearing problem recovered and some of the abnormal electrophysiological parameters were corrected.     

Cerebral glucose utilization is reduced in second test session

Cerebral glucose utilization was higher during the first positron emission tomography (PET) session than during the second session, as assayed using the PET [18F]fluorodeoxyglucose method in male human volunteers. This difference was due largely to data from subjects with low-trait anxiety, since subjects with high anxiety showed similar metabolism in both PET sessions. High-anxiety subjects showed greater right/ left ratios of cerebral metabolism than low-anxiety subjects, particularly during the second PET session. These findings suggest that the level of anxiety may be an important variable to consider in PET studies using multiple sessions.     

Nephrolithiasis--rational etiological assessment

Although underlying metabolic abnormalities do not differ fundamentally in patients with either first or recurrent nephrolithiasis and 35% of patients with a first event may have to face a recurrence 5 years later, extended metabolic investigations in patients with a first renal calculus should be restricted to particular, exceptional cases. However, in patients with a first calculus basic investigations with respect to specific causes for a concrement such as primary hyperparathyroidism, incomplete renal-tubular acidosis, recurrent urinary tract infection and cystinuria are mandatory. This includes, in addition to a laboratory investigation of blood and urine after a 2-hour-fasting period, analysis of the stone and a urography. The extended metabolic investigation in patients with recurrences or a first occurrence in a patients with a risk constellation includes evaluation of the most important lithogenic (calcium, oxalate, phosphate, uric acid) and inhibiting components (citrate) in the 24-hour urine, in patients with cystine calculi quantitation of cystine. A metabolic investigation should never be undertaken in the hospital or under standardized diet, but always under accustomed, unrestricted nutrition. At least 2 urine samples should be investigated from each patient, preferably not prior to 3-4 months after the event when homeostasis of the patient is restored analogously to the onset of concrement development.     

Positron emission tomography of auditory sensation in deaf patients and patients with cochlear implants

The present study investigated the function of the auditory cortices in severely hearing-impaired or deaf patients and cochlear implant patients before and after auditory stimulation. Positron emission computed tomography (PET), which can detect brain activity by providing quantitative measurements of the metabolic rates of oxygen and glucose, was used. In patients with residual hearing, the activity of the auditory cortex measured by PET was almost normal. Among the totally deaf patients, the longer the duration of deafness, the lower the brain activity in the auditory cortex measured by PET. Patients who had been deaf for a long period showed remarkably reduced metabolic rates in the auditory cortices. However, following implantation of the cochlear device, the metabolic activity returned to near-normal levels. These findings suggest that activation of the speech comprehension mechanism of the higher brain system can be initiated by sound signals from the implant devices.     

Left atrial size changes in patients with paroxysmal lone atrial fibrillation. An echocardiographic follow-up

Left atrial enlargement has been demonstrated to occur as a consequence of the arrhythmia in patients with chronic atrial fibrillation (AF) in the absence of organic heart disease, whereas contrasting results have been reported in patients with paroxysmal lone AF. In the present investigation the behavior of left atrial size was followed up for an average period of 30.3 months in 20 patients with paroxysmal lone AF since their first arrhythmic episode. No significant changes in left atrial size were found at the end of the follow-up period. In 65% of patients the arrhythmia recurred at least once yearly. Left atrial size at enrollment was not significantly different in these patients from those without recurrences and did not change in either group during follow-up. The results suggest that in patients with lone AF left atrial dilatation occurs only after the arrhythmia becomes chronic. Early restoration of sinus rhythm may interrupt the vicious circle leading to atrial enlargement.     

Microcirculation disorders of the skin

Medical patients' (75 with chronic fatigue complaints, 61 with dizziness, and 88 with disabling tinnitus; N = 224) current and past psychiatric diagnoses and personality characteristics were assessed to determine if they could independently explain the number of medically unexplained physical symptoms that the patients had experienced. Cloninger's Tridimensional Personality Questionnaire (TPQ) and the Diagnostic Interview Schedule based on DSM-III-R were used to assess the personality and psychiatric diagnoses, respectively. The results revealed that the number of lifetime medically unexplained symptoms were significantly, independently, and positively related to increasing numbers of current and past anxiety and depressive disorders and to the harm avoidance dimension of the TPQ. In a second analysis, the "worry/pessimism" and "impulsiveness" subscales were positively related to the number of medically unexplained symptoms. The results suggest that somatization is associated with current and past history of psychiatric illnesses and harm avoidance in this sample of medical patients.     

Cerebral glucose metabolism in patients with frontotemporal dementia

Frontotemporal dementia (FTD) is a dementia syndrome characterized by peculiar behavioral changes arising from frontotemporal involvement and distinct from Alzheimer's disease (AD). The purpose of this study was to elucidate the specific patterns in cerebral glucose metabolism in patients with FTD and to compare them with the patterns in patients with AD and normal elderly subjects using fluorodeoxyglucose (FDG) and PET. METHODS: Twenty-one patients with a clinical diagnosis of FTD [mean age 67.0 +/- 7.0 yr, Mini Mental State Examination (MMSE) score 18.7 +/- 5.7], 21 age-, sex- and dementia-severity-matched patients with probable AD (mean age 66.9 +/- 7.1 yr, MMSE score 20.2 +/- 5.5) and 21 age- and sex-matched normal control subjects (mean age 66.8 +/- 5.7 yr) were studied. The cerebral metabolic rate for glucose (CMRglc) was measured with FDG and PET. Absolute measures of regional CMRglc were compared among the three groups. One-way ANOVA and the posthoc Tukey HSD test were used for statistical analyses. RESULTS: In the FTD group, CMRglc was preserved only in the left cerebellum, right sensorimotor area and occipital lobes. The CMRglc was significantly lower in the FTD group as opposed to the AD group in the hippocampi, orbital gyri, anterior temporal lobes, anterior cingulate gyri, basal ganglia, thalami, middle and superior frontal gyri and left inferior frontal gyrus. CONCLUSION: Although metabolic abnormality in FTD is predominant in the frontal and anterior temporal lobes and the subcortical structures, it is more widespread than has been previously stressed. These findings document an FTD-specific cerebral involvement and facilitate differential diagnosis of degenerative dementias.     

Effects of relaxation therapy as group and individual treatment of chronic tinnitus

42 patients, suffering from chronic tinnitus, participated in our psychological orientated treatment consisting of relaxation therapy with autogenic training according to J. H. Schultz. The results of individual therapy are compared with group therapy. Using visual analogy scales the therapeutical efficiency can be tested. The individual estimated loudness and annoyance of tinnitus are registered as well as a general emotional status. The results show a positive short-time effect in most cases. A reduction of tinnitus loudness and annoyance after individual and group therapy is seen directly. A positive effect throughout the whole treatment is only found in individual therapy. Concerning the group therapy, many of our patients reported an increase of the pretherapeutical estimation of tinnitus loudness and -annoyance. We believe that the permanent confrontation with the tinnitus problem may advance the psychological conflict in many cases. Therefore psychological management of tinnitus should be concentrated on a temporary limited support aiming to the neglect of tinnitus sensation.     

High-resolution cardiac PET in rabbits: imaging and quantitation of myocardial blood flow

A high-resolution PET system for small animals was tested for its applicability to the investigation of regional myocardial blood flow (MBF) in rabbits. METHODS: Nineteen measurements were performed in 10 closed-chest anesthetized rabbits at baseline and during infusions of adenosine (0.2 mg/kg/min) and propranolol (0.20-1.20 mg slow infusion) to obtain a wide range of MBF. Myocardial blood flow was assessed both by dynamic 13N-ammonia PET and by colored microspheres. Blood was withdrawn directly from the femoral artery, and arterial 13N activity was measured by coincidence type gamma detection system for the input function. Nitrogen-13 myocardial uptake was calculated by dividing the myocardial 13N activity by the integral value of the input function. RESULTS: Three or four contiguous cross-sectional myocardial images were obtained after 13N-ammonia injection. The left ventricular wall and cardiac cavity were clearly visualized. Moreover, initial passage of the tracer through the heart was obtained with serial 10-sec PET images. Nitrogen-13 myocardial uptake correlated well with flow measured with microspheres (r = 0.88). CONCLUSION: Our cardiac PET system can be used for in vivo imaging and quantitation of MBF in small animals and may play an important role in the future study of animal models of cardiovascular diseases.     

The effect of traditional Chinese acupuncture on severe tinnitus. A double-blind, placebo-controlled clinical study with an open therapeutic surveillance]

The aim of the present study was to determine the effect of intensive acupuncture on severe tinnitus. The structure of the study was a randomized, double-blind, clinical investigation with open therapeutic surveillance and included 54 patients. All were subjected to 25 treatment sessions over a period of two months, each treatment lasting 30 minutes. Fifty-two patients completed the study. The variables used for self-registration were based on the Visual Analogue Scale, where annoyance, loudness and awareness of the tinnitus were assessed. These were recorded twice daily over a four month period starting one month before the first treatment and ending one month after the last treatment. Questionnaires, interviews and audiometry were carried out repeatedly. No statistically significant differences were found between the acupuncture group and the placebo group.     

Sleep complaints in chronic postconcussion syndrome

This study was designed to identify the incidence of sleep complaints in 39 patients with chronic postconcussion syndrome compared to those of a control group of 27 patients with orthopedic injuries. Patients with orthopedic injuries were selected as a comparison group to control for the effects of traumatic injury or chronic pain. There were no differences in age, sex distribution, or time from injury between the patient groups. Type and frequency of sleep disturbances in a mean two-year postinjury period were evaluated. Patients with chronic postconcussion syndrome reported more difficulty in initiating and maintaining sleep at night and greater difficulty with sleepiness during the day.     

Acupuncture worth trying in severe tinnitus

The article consists in a report of a study of 22 patients with disabling tinnitus, performed to elucidate the effects of a 3-month course of acupuncture (15 treatments) on the severity of tinnitus and on quality of life (QOL), as compared with those of individualised physiotherapy. The study was designed as a prospective, randomised, cross-over study with a follow-up period of one year after the final treatment. Treatment effects were evaluated in terms of the patients' VAS (visual analogue scale) ratings and answers to questionnaires, including the NHP (Nottingham Health Profile), regarding the impact of tinnitus on different aspects of QOL. Baseline NHP scores showed tinnitus patients to manifest pronounced depressive characteristics. Acupuncture was found to yield immediate relief, both in terms of loudness and disturbance of the tinnitus, and significant improvement in QOL (NHP) for three months after the conclusion of treatment. Although many patients in the subgroup with concurrent muscle tension reported beneficial effects of individualised physiotherapy, such treatment yielded no significant reduction of tinnitus loudness or disturbance due to tinnitus, and no improvement in NHP scores. In both treatment groups, however, both annoyance due to tinnitus and QOL scores had returned to pretreatment levels at one-year follow-up. Thus, the results suggest tinnitus patients to manifest depressive characteristics, and that acupuncture may yield temporary improvement in terms of tinnitus relief and QOL.     

Noninvasive blood glucose monitoring

This prospective review of adult patients with head injuries examines the incidence of head injuries due to falls caused by seizures, the incidence and severity of intracranial hematomas, and the morbidity and mortality rates in this patient population. A head injury was attributed to a fall caused by a seizure if the seizure was witnessed to have caused the fall, or the patient had a known seizure history, appeared postictal or was found convulsing after the fall, and no other cause for the fall was evident. A total of 1760 adult head-injured patients were consecutively admitted to the authors' service between 1986 and 1993. Five hundred eighty-two head injuries (33.1%) were due to falls and 22 (3.8%) of these were caused by seizures. Based on the prevalence rates for epilepsy in the general population of 0.5 to 2%, these results indicate that epileptics are several times more likely to suffer a head injury due to a fall. Mass lesions were found in 20 (90.9%) of these 22 patients and the remaining two patients suffered mild diffuse head injuries. There was a high incidence of extraaxial mass lesions: 17 (85%) of the 20 intracranial hematomas were either epidural (five cases) or acute subdural (12 cases) hematomas. Eighteen (81.8%) of the 22 patients required evacuation of a hematoma. Both the incidence of intracranial hematomas (90.9% vs. 39.8%, p < 0.001, chi-square analysis) and the rate of hematoma evacuation (81.8% vs. 32.3%; p < 0.001) was significantly greater in patients injured in falls due to seizures (22 cases) than in the group injured in falls from all other causes (560 cases). The higher incidence of hematomas and the need for evacuation were not explained by differences in age, seventy of head injury, or incidence of alcohol intoxication. Despite the greater incidence of mass lesions and the need for operative treatment in patients injured because of seizures, their mortality rate was similar to that of patients injured in falls from other causes. On the basis of their review of patients admitted to a neurosurgical center with complaints of head injury, the authors conclude that patients with head injuries due to a fall caused by a seizure should undergo computerized tomography scanning early in their management. Until a mass lesion has been excluded, any decrease in level of consciousness or focal neurological deficit should not be attributed to the seizure itself.     

Neuroprotection: the next breakthrough in glaucoma? Proceedings of the Third Annual Optic Nerve Rescue and Restoration Think Tank

OBJECTIVES: To document the efficacy of combined epidural steroid injection (ESI) and manipulation to the lumbar spine in patients suffering from chronic low back pain (LBP). SUMMARY OF BACKGROUND DATA: The use of ESI in conjunction with lumbar manipulation has seldom been reported in the literature but has offered promising results when studied. STUDY DESIGN: Retrospective repeated-measures analysis of patients with chronic LBP who received ESIs combined with spinal manipulation. METHODS: A retrospective analysis using a repeated-measures format was performed on 17 cases of patients who had received ESI and manipulation to the lumbar spine. All patients were medically stable for chronic mechanical LBP and had experienced a suboptimal response to conventional care. The principle investigator was blinded from data outcomes when determining patient eligibility for the study. A subjective patient improvement scale was used to monitor degree of success. RESULTS: Ten of the 17 patients were eligible for the study. Patients were eliminated for lack of consistency of data collection, having received an additional procedure after conventional care, involvement of the cervical spine; one patient experienced an unrelated medical problem. After 1 yr of conventional care, the patients reported a 25.5% improvement. (Conventional care included ESI and manipulation done at separate times.) After on ESI with subsequent manipulation, these same patients reported a 50.5% improvement. Mean improvement was 25.00% (SD = 19.51, SEM 6.19, t = 4.04 and p = .0015). CONCLUSION: The use of ESI performed with manipulation seems to offer promise for a carefully selected group of patients. ESI combined with manipulation should be considered in patients who do not respond to conventional forms of care.     

Regional cerebral blood flow in focal cortical epilepsy

Regional cerebral blood flow (rCBF) was studied in ten patients with focal cortical epilepsy. The blood flow was measured by the intra-arterial injection of xenon 133 (133Xe), and the isotope clearance was recorded by a multidetector scintillation camera with 254 detectors. Three patients were studied both during a seizure and (in the same setting) in the interictal period; six patients were studied only in the interictal period, and one patient was studied only during a seizure. Studies during seizures all showed marked flow increases in areas presumed to participate in the seizure activity. This finding accords with earlier studies. All nine patients studied in the interictal phase showed, either spontaneously or during activation by intermittent light, focal flow increases in areas presumed to comprise the epileptic focus. These interictal hyperemic foci probably reflect subictal neuronal hyperactivity in epileptogenic nervous tissue. Only two of the patients had distinct epileptic electroencephalographic foci. It appears that rCBF studies can be a valuable diagnostic tool in the investigation of cortical epileptogenic lesions.     

Quality of death certificates in cases of cancer death in France

The prognosis of pulmonary tumor embolism is said to be poor and only a limited number of patients with this disease have survived. The patient was a 64-year-old male suffering from left renal cell carcinoma complicated with tumor extending from the left renal vein to the inferior vena cava. The patient underwent an operation for left renal cell carcinoma during which he developed tumor embolus to the pulmonary artery. The occurrence of the acute embolism was promptly detected and the removal of tumor was performed under cardiopulmonary bypass. The patient made good postoperative progress.