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Objective: To evaluate the possible role of the default mode network (DMN) in consciousness and assess the diagnostic or prognostic potential of DMN connectivity measures in the assessment of a patient group lacking cognitive awareness. Methods: DMN connectivity was established using independent component analysis of resting-state fMRI data in patients with reversible (n = 2) and irreversible (n = 11) coma following cardiac arrest and compared to healthy controls (n = 12). Results: A present and intact DMN was observed in controls and those patients who subsequently regained consciousness, but was disrupted in all patients who failed to regain consciousness. Conclusions: The results suggest that the DMN is necessary but not sufficient to support consciousness. Clinically, DMN connectivity may serve as an indicator of the extent of cortical disruption and predict reversible impairments in consciousness.

The syndrome of involuntary craniofacial lingual movements in the setting of acute intensive care-acquired quadriplegia (critical illness neuromyopathy) following sepsis-associated encephalopathy has not been previously described. We suggest a localization and treatment for this disabling condition.Three patients (2 female) from our center were quadriplegic from critical illness neuromyopathy when they developed involuntary craniofacial lingual movements following sepsis-associated encephalopathy.Extensive investigations failed to identify an etiology for the abnormal movements. Movements were of large amplitude, of moderate speed, and semi-rhythmic in the jaw, tongue, and palate, persistent and extremely bothersome to all patients. Injection with Botulinum toxin type A was very beneficial.Involuntary craniofacial lingual movements in the setting of flaccid quadriplegia following sepsis-associated encephalopathy are consistent with focal craniofacial brainstem myoclonus and constitutes a new syndrome. Botulinum toxin type A treatment maybe helpful in treatment.

Forty-three patients who had sepsis and multiple organ failure (critical illness) were studied prospectively to determine the incidence and severity of peripheral nerve function and to correlate such function with a number of variables. Electrophysiologic studies indicated a primary axonal degeneration of motor and sensory fibers in 30 (70 percent). Fifteen (30 percent) had the clinical signs of difficulty in weaning from assisted ventilation, weakness of limb muscles, and reduced or absent deep tendon reflexes. Full recovery from the polyneuropathy occurred among the 23 (53 percent) who survived, except three who had a very severe polyneuropathy. A peripheral nerve function index, computed from electrophysiologic measurements, showed statistically significant (p less than 0.01) negative correlations with the time in the critical care unit, and the serum glucose value; the serum albumin level showed a positive correlation. Multiple regression analyses indicated all three factors accounted for 47 percent (r2 = 0.4678) of all potential variables. In a separate analysis, the nerve function index correlated with the amplitude of the diaphragm compound muscle action potential (p less than 0.01). The results were consistent with the polyneuropathy being due to the same mechanisms that are currently postulated to cause dysfunction in this syndrome of other organ systems (including the neuromuscular respiratory system).

Of 49 patients with nonconvulsive seizures studied with continuous EEG monitoring, the overall mortality was 33% (16/49).Of the 23 patients with nonconvulsive status epilepticus (NCSE), 13 died (mortality 57%). Individual variables significantly associated with mortality were age, presence of NCSE, seizure duration, hospital and NICU length of stay, and delay to diagnosis and etiology (acute illness versus remote symptomatic). With multivariate logistic regression, only seizure duration (p = 0.0057, OR = 1.131/hour) and delay to diagnosis (p = 0.0351, OR = 1.039/hour) were associated with increased mortality. Acute symptomatic cases could not be adequately classified as either absence, simple, or complex partial status epilepticus when the impairment of consciousness arose from the initial illness. Current classifications of status epilepticus are inadequate for such cases.NEUROLOGY 1996;47: 83-89

OBJECTIVE: To document the criteria used to declare brain death in a pediatric critical care unit (PCCU). DESIGN: Retrospective chart review. SETTING: Regional PCCU in southwestern Ontario. PATIENTS: Sixty patients 16 years of age or less declared brain dead from January 1987 through December 1992. OUTCOME MEASURES: Presence or absence of documentation of irreversible deep coma, nonresponsive cranial nerves, absent brain-stem reflexes, persistent apnea after removal from ventilator, presence or absence of blood flow detected by radioisotope scanning, presence or absence of electroencephalographic evidence of electrocerebral activity. RESULTS: The 60 patients accounted for 1.5% of all PCCU admissions; 17 were under 1 year of age. In 39 cases brain death was diagnosed using clinical criteria ("certified brain death"), which could not be fully applied in the remaining 21 cases ("uncertifiable but suspected brain death"). Electroencephalography and cerebral blood-flow studies with technetium-99m hexamethyl-propyleneamine oxime were used as ancillary tests in 16 patients with certified brain death and in 17 with uncertifiable but suspected brain death who survived long enough to be tested. Electrocerebral silence was demonstrated in all nine patients who underwent electroencephalography. Cerebral blood flow was undetectable in 26 of the 30 patients tested, and an abnormal pattern of blood flow was seen in the remaining 4, all of whom received a diagnosis of certified brain death. CONCLUSIONS: Pediatricians in this large tertiary care referral centre are using clinical criteria based on the 1987 guidelines of the CMA to diagnose brain death in pediatric patients, including neonates. When clinical criteria cannot be fully applied, ancillary methods of investigation are consistently used. Although the soundness of this pattern of practice is established for adults and older children, its applicability to neonates and infants still needs to be validated.

Neurologic complications of systemic illnesses may affect any part of the nervous system in various conditions. In many systemic disorders, however, an acute confusional state is the first manifestation. It is urgent to make a definitive diagnosis and begin specific and supportive therapy to lessen mortality and morbidity. A case of severe septic illness with central and peripheral nervous system complications is reviewed. Septic encephalopathy and critical illness polyneuropathy are common conditions in the general ICU. The neuropathy often is the underlying cause for failure to wean from the ventilator.

We report 11 adults who exhibited myoclonic status epilepticus (MSE) after cardiac arrest. Based on pathologic, electroencephalographic, and clinical evidence, we conclude that our patients died from the initial anoxic-ischemic insult rather than as a result of MSE. We suggest that the seizures in these nonsurvivors were self-limited events arising from lethal damage to neurons. Thus, in patients with bilaterally synchronous facial myoclonus, bilateral loss of pupillary or oculovestibular reflexes, and suppression and burst-suppression on EEG, it is not warranted to use anesthetic barbiturates to treat MSE.

The Edinburgh Breast Screening Clinic in its first year completed the initial screening examination of 3005 invited women, who were apparently in good health, aged between 40 and 60 years; 141 were referred for a surgical opinion; 70 women ultimately underwent biopsy and 9 proved to have carcinoma. The indications for biopsy are described together with methods of management of the various lesions.

Myo-inositol was given orally to nine multiple sclerosis patients and nine healthy control subjects. Pattern reversal evoked potential testing was used to assess its effect. The principal positive wave increased in amplitude, duration and area in a dose-dependent manner in the multiple sclerosis group compared with controls. Cerebrospinal fluid concentrations of myo-inositol in multiple sclerosis and controls were similar. The significance of these observations is discussed in relation to recent discoveries in inositol phospholipid function.

The principal ultrasonic signs of death of the fetus in the first 12 weeks of pregnancy are reviewed and illustrated. Several new signs, one probably due to CO2 in the conceptus, are recorded. The use of two-dimensional B scanning and multiplanar stereoscopic sonar is made.

1. A case of duplication of the stomach followed over a period of 23 years is described. 2. Radiological evidence of peptic ulceration in the wall of the duplication is recorded. 3. Aspects of the aetiology, symptomatology and treatment of this rare condition are discussed.

With the increasing use of mammography in the diagnosis and follow-up of breast cancer, the question of radiation hazard has become of considerable interest (Ostrum, Becker and Isard, 1973; Samuel, 1973). There can be no doubt that ionizing radiation, given in sufficient quantity, is carcinogenic. There is evidence in a number of clinical reports (MacKenzie, 1965; Myrden and Hiltz, 1969; Mettler, 1969; Mole, 1973; Wanebo et al., 1968) as well as additional evidence from experimental work (Shellabargar et al., 1957). Whether one or two sets of mammograms are sufficient to induce malignant change in a breast is more doubtful. However, in problem cases of breast disease, and in screening procedure for breast cancer where yearly mammograms are the custom, irradiation of the breast can mount up rapidly, and apparently dangerous levels of radiation can be reached. Such levels can be greatly reduced if the rads per exposure are kept low (Young, 1974). There has been speculation on the probable increased incidenc...

Three hundred cases in which both ultrasonic and soft tissue placentography examinations had been done are correlated with each other and the clinical findings. These are grouped in two series, one in 1972-1973 and the other 1973-1974. The accuracy rate for both methods was 95 per cent. Outright errors were 2 per cent, and cases in which correlation was lacking for reasons other than diagnostic errors were 3 per cent. Reasons for this lack of correlation are discussed and illustrated. Seven examples of the ascending (or migrating) placenta were also found and an illustrative case is described.

The daily growth rates of ovarian follicles were recorded ultrasonically for five days until ovulation in 56 spontaneously ovulating women and related to endocrine and clinical parameters. Over the 5-day period, the average diameter of the follicle destined to ovulate increased from 12 to 23 mm, the second largest follicle from 6 to 12 mm, the third largest follicle from 5 to 9 mm and the fourth largest follicle from 4 to 8 mm. Similar but lesser growth rates occurred in the follicles in the contralateral ovary. Ovulation occurred within 24 hours of the luteinizing hormone (LH) peak, and the mean peak diameter of the ovulating follicle was 23.2 +/- 0.3 (SEM) mm, (range 18-29 mm) before ovulation, and subsequent luteal function was judged to be normal. Follicular growth was most closely correlated with increasing peripheral blood oestrogen levels. In 16 women who had a laparoscopy within 12 hours of the last ultrasound and following the LH peak, the mean diameter of the largest follicle as measured by ultrasound (23.6 +/- 0.4 mm) was similar to that measured at laparoscopy (22.8 +/- 0.04 mm) and estimated from the volume of follicular fluid aspirated (average 5.8 +/- 0.2 ml), 22.5 mm. The follicular fluid levels of progesterone were high on the day of the LH peak and blood progesterone levels had risen significantly indicating that luteinization of the dominant Graafian follicles had already occurred prior to ovulation. This study confirms that ultrasonic monitoring provides a reliable measure of follicular growth and allows studies correlating morphological changes with both normal and abnormal endocrine function of the human ovary.

Human lymphocytes and Chinese hamster ovary (CHO) cells in culture were exposed for 12 1/2 hours to a magnetic resonance imaging apparatus with a 2.35-Tesla magnet and 100-MHz radio frequency emission. The cells were examined for cytogenetic damage manifested either as chromosome aberrations or sister chromatid exchanges (SCEs), which constitute very sensitive measures of genetic and cellular damage. In either unstimulated or stimulated human lymphocytes, as well as in exponentially growing CHO cells, no increase in either chromosome aberrations or SCEs was found as a result of exposure to these MR conditions. The data indicate that long-term exposure to MR imaging conditions far exceeding those to be found in the clinical situation does not cause cytogenetic damage.

Two weeks after gastric partitioning for morbid obesity, a 45-year-old woman experienced persistent vomiting that led to a weight loss of 30 kg over 6 weeks. Wernicke's encephalopathy and peripheral neuropathy developed. The Wernicke's encephalopathy responded well to the administration of thiamine. This is one of very few reported cases of Wernicke's encephalopathy following gastric partitioning.

To obtain satisfactory mammograms kilovoltages of below 35 must be used. At higher levels the difference of absorption between the fat, connective tissue and glandular parenchyma of the breast is so small that adequate contrast is not attained (Siler, Snyder, Garrett, Laughlin and Sherman, 1964; Stanton, Lightfoot, Boyle and Cullinan, 1963). Whether industrial or standard unscreened film gives the best results is still debated. Added detail at the expense of added irradiation is undoubtedly obtained by the use of industrial film (Egan, 1964), but satisfactory contrast can be achieved by the use of both types of film (Curcio, 1962). The controversy would appear to be largely a question of personal preference and usage.

We report two cases of serious intracerebral haemorrhage occurring in young women following their first use of oral medications containing catecholaminergic agents (phenylpropanolamine in combination with ephedrine or pseudoephedrine). Both women were previously well, and there was no evidence for systemic vasculitis, coagulopathy, aneurysm or arteriovenous malformation. Angiography in both cases, performed approximately forty hours following drug ingestion, revealed the beading pattern typical of that seen in previously reported cases of presumed amphetamine-induced "vasculitis." We believe that this arteriographic abnormality is non-specific and should not be construed as necessarily indicative of arteritis.

A comparison of clinical, EEG, and pathologic features was carried out on all cases of autopsy-proven Creutzfeldt-Jakob disease (CJD) studied over the last 10 years. Periodic sharp wave complexes (PSWCs) were present in three but absent in seven patients. Myoclonus was documented in two of the three with and in only one of the seven without PSWCs. The three with PSWCs had severe neocortical and at least mild thalamic involvement; those without PSWCs had more variable disease topography. The diagnosis of CJD should not be rejected if PSWCs are absent.