Complete suppression of spontaneous decay of a manifold of states by infrequent interruptions.

Complete suppression of spontaneous decay of a manifold of states is shown to be achievable in a model system by a combination of coherent excitation of overlapping resonances and a judicious infrequent application of microwave pulses.

Coherently controlled asymmetric synthesis with achiral light

A laser-based method of increasing the enantiomeric excess of a chiral enantiomer in a racemic mixture is described. Neither the initial reagents nor the incident light need be chiral. Both formal and computational results show that enhancement of the enantiomer of choice, controlled by laser parameters, can be extensive.

CT demonstration of intracranial bleeding in term newborns with mild clinical symptoms.

This paper presents symptomatic term newborns with negative ultrasound examination which showed intracranial bleeding demonstrated by CT scan. Fifty-eight term newborns with Apgars of 9-10 were referred for repeat CT examination of the brain with symptoms, such as apnea, disturbances of swallowing or sucking, impaired muscular tonus, tremor and jerks. The ultrasound examination in all was normal. The first CT scan was performed 12-13 h after delivery. The second CT scan was performed at least two weeks later. Twenty-three of the patients underwent lumbar puncture. Physical examination was performed on each patient--at birth and one week later. The clinical symptoms were still present at the time of the second physical examination. Fourteen to seventeen months following the delivery, the psychomotor development was evaluated in 29 of the children using the Gesell test. In five children, the diagnosis of psychomotor retardation was established which correlated with the brain atrophy demonstrated on CT. Twenty-three newborns who underwent lumbar puncture showed evidence of bleeding into the subarachnoid space. The blood haemoglobin levels of all the cases was below 18 g/dl. The first CT examination demonstrated blood in the subarachnoid space. The second CT scan did not demonstrate any findings. Intracranial bleeding in newborns may be associated with normal delivery. The demonstration of high densities in the first CT scan, the normal second CT scan, the blood tinged or xantochromic CSF and the normal blood haemoglobin levels are indicative of intracranial bleeding.

CT of minor intubation trauma with clinical correlations.

Even when performed by an experienced physician, endotracheal intubation is more traumatic than previously supposed. Following emergency intubation, patients have little probability of having a normal larynx. One-hundred patients underwent CT scan of the larynx 6 months or more following endotracheal intubation of short duration (up to 8 h). Ten patients (Group 1) with respiratory arrest underwent emergency intubation; 90 surgical patients (Group 2) underwent anesthesia with endotracheal intubation. Indirect laryngoscopy was performed in 59 symptomatic patients. Abnormal CT findings were present in 86 out of 100 patients. CT irregularities, which included tears, scars and small laryngoceles, were noted on indirect laryngoscopy in 59 symptomatic patients. The laryngeal damage following endotracheal intubation is surprisingly high.

CT evaluation of otorrhagia associated with condylar fractures.

To assess a simplified CT evaluation of otorrhagia due to condylar fracture, 16 patients with post-traumatic otorrhagia underwent axial CT of the petrous bones and coronal CT of the temporo-mandibular joints (TMJs). Bilateral high condylar fractures were demonstrated in seven patients. Unilateral subcondylar fracture dislocations with contralateral high condylar fractures were demonstrated in the other nine patients. The otorrhagia was always ipsilateral to a high condylar fracture. Otorrhagia due to condylar fractures occurred when the fracture was bilateral and ipsilateral to a high condylar fracture. The diagnostic procedure of choice is coronal CT of the TMJs which should be carried out if axial CT of the petrous bones showed them to be intact.

Spina bifida occulta of S1 is not an innocent finding.

One thousand two hundred patients (600 women and 600 men) aged 18 to 72 years were referred for computed tomographic examination of the lumbosacral spine (L3-S1) after low-back pain or sciatica. Patients with spinal abnormalities other than spina bifida occulta (SBO)-S1 and findings other than posterior herniation of intervertebral disc were not included in this study. All of the patients underwent conventional radiographs of the lumbosacral spine. The incidence of SBO-S1 was higher in younger age groups and decreased with age. Patients with SBO-S1 showed a higher incidence of posterior disc herniation, which increased with age. This can be explained by instability of the base of the lumbar spine caused by SBO-S1, which produces a predisposition to posterior disc herniation. The results were statistically significant.

Infected renal cysts: sonographic diagnosis and management.

IRC are rare entities characterized by fever and unilateral flank pain resistant to antibiotic therapy. In our series of nine IRC in eight patients, the predominant sonographic finding was an abnormal echogenic texture of the cyst contents, in contrast to previous reports that stressed the frequency of wall thickening as a sign of infection. Sonographically guided cyst aspiration and drainage of eight cysts in seven patients provided diagnostic material and resulted in relief of symptoms. Although the cause of IRC is uncertain, these entities may be more common than previously suspected.

Computed tomography of healing condylar fractures with some clinical correlations.

A longitudinal study using computed tomographic (CT) examinations has been performed in 79 patients with condylar fracture of the temporomandibular joint (TMJ). CT scans were performed following healing to demonstrate the new condylar shape. Maximal incisor distance was measured in all patients. Patients with mild deformities of the condyles had satisfactory function of the TMJs with a maximal distance between the incisors that was similar to 50 healthy controls (average 45 mm). Fifteen patients with severely deformed condyles and an abnormal shape of the glenoid fossa had an average maximal distance between the incisors of 16 mm which corresponded with severe malfunction of the TMJs. The remaining 42 patients with moderate condylar deformity had an average maximal distance between the incisors of 29 mm and the disability of the TMJs was considered to be moderate. The results were statistically significant. There was no resorption of the fractured condylar head or bone fragment. The correlation of the fractured head or fragment and the remodelling of the condyle during the healing process determined the final alignment of the fractured condyle to the glenoid fossa on which the TMJs' function was dependent.

CT demonstration of intracranial haemorrhage in term newborn following vacuum extractor delivery.

Ten term newborns underwent CT of the brain 12-24 h following vacuum extractor delivery. Haemorrhage in the area of the tentorium was demonstrated in all of them, with similar findings in all cases. CT 1 week later demonstrated reabsorption of the blood without demonstrating any other brain pathology. Clinical and CT examination a year after delivery did not reveal any abnormality. The haemorrhage appears to be a benign condition.

CT evidence of mucosal thickening in the maxillary antra in patients with nasopharyngeal carcinoma.

CT scans of the maxillary antra in a group of 51 patients with nasopharyngeal carcinoma were compared with those of a control group of 50 patients. Inflammatory thickening of the antral mucosa was demonstrated in 39 of 42 patients with grade WHO (World Health Organization) 2 and 3 nasopharyngeal carcinoma. Biopsy of the antral mucosa in eight of these patients established inflammation and excluded the presence of nasopharyngeal carcinoma in the antrum. In a group of nine patients with WHO 1 tumors, the antral mucosa was normal. Thickening of the antral mucosa was observed in six patients of the control group. The inflammatory thickening of the antral mucosa in the patients with WHO 2 and 3 tumors was obviously more frequent than in the control group. This combination was not found in patients with WHO 1 tumors. The phenomenon cannot be explained by direct extension of nasopharyngeal carcinoma or obstruction of the maxillary osteum. The cause of the mucosal thickening may be immunologic, but remains unclear at this stage. The high frequency of inflammatory thickening of the antral mucosa observed in patients with WHO 2 and 3 tumors should encourage further investigation of causative factors in nasopharyngeal carcinoma.

Epidural haematoma: computerized tomography (CT) parameters in 19 patients.

Between the years 1984 to 1989, 624 urgent brain CT examinations were performed for head-trauma patients in the Tel-Aviv Medical Center. In 19 patients, epidural haematomas were diagnosed. Different radiological parameters were discussed such as homogeneity of the haematoma, midline shift, ventricular collapse, obliteration of the peri-mesencephalic cistern and the presence of additional brain damage.

Magnetic resonance imaging (MRI) in patients with complex partial seizures and normal computerized tomography (CT) scan.

Magnetic resonance imaging (MRI) examination was performed in 18 patients with complex partial seizures (CPS) of long duration, who had normal computerized tomographic (CT) scans of the brain. Small MRI abnormalities correlating with the location of the epileptogenic focus in the EEG were demonstrated in 4 cases. The findings with strong signals were better demonstrated in the coronal view with longer time to echo (TE). In one patient, a lower signal lesion was documented, which was better visualized in the axial view with shorter TE. Patients with CPS should be subjected to MRI examinations with coronal and sagittal planes, using short and long TE in each slice. This method minimizes the chance for missing pathology.