Mycobacterial infection in an inner city children's hospital

Childhood tuberculosis is perceived by many as a disease of the past. Experience in a children's hospital serving a deprived population suggested that tuberculosis and other mycobacterial infections were not declining in clinical practice. Fifty three tuberculous and 11 atypical mycobacterial infections were identified between 1978 and 1992. There was no decline in tuberculosis and nine of the 11 atypical infections occurred in the last five years. Altogether 40% of cases of tuberculosis were in non-Asian children; 32% had arrived in the UK or visited family overseas in the previous year; and 38% had a history of tuberculosis contact, usually a close adult relative. Nationally, the previous decline in tuberculosis in all ages has reversed. In the local health districts in London's east end, childhood tuberculosis has also stopped declining and seems to be increasing. It is regrettable that BCG vaccination has been abolished by some districts in the UK, against current recommendations. Childhood tuberculosis is still common in the practice described here, including among children who do not fall into conventionally recognised high risk groups. Inner city dwellers and junior doctors are both highly mobile populations, adding to the risk that paediatricians, particularly those in training, may encounter tuberculosis with little or no previous experience of the condition.     

MR imaging of blood vessels using three-dimensional reconstruction: methodology

Multisection, dual-echo magnetic resonance (MR) transaxial images of blood vessels contain both anatomic and qualitative information about flow. Even so, the images are produced as a series of two-dimensional tomographic sections from which full visualization of connected structures is difficult. A computer algorithm was developed that automatically detects flowing blood based on pixel intensity and calculated T2 and provides reconstructed views of vessels while analyzing and displaying flow characteristics. Images of abdominal vessels, aortic aneurysms, and the heart were encoded by flow and color to demonstrate depth. In addition, these data were reconstructed to derive a more accurate assessment of patency. With this technique, transaxial images can be used to analyze flow patterns, determine patent areas, and visualize all levels of vessels in a single image.     

Squamous cell carcinoma of the larynx with osteosarcoma-like stromal metaplasia

Osseous or chondroid metaplasias are uncommonly found adjacent to laryngeal squamous cell carcinoma (SCC). These findings are less unusual in the spindle cell variant. We describe a moderately differentiated laryngeal SCC associated with osteocartilaginous metaplasia of the adjacent stroma which exhibited very similar morphologic changes and mitoses to an osteosarcoma. These uncommon findings can be more clearly understood if they are viewed as changes determined by the microenvironment of the tumour-host interface, as indicated in recent studies. Tumour cells seem able to regulate stromal development and differentiation via the release of growth factors and the induction of growth factor receptor expression on the cell surface. Irrespective of the limited number of reported cases, the association of SCCs of the larynx with osteocartilaginous metaplasia does not seem to support the adoption of treatments of choice that differ in approach to those for site- and stage-matched SCCs without osteocartilaginous metaplasia.     

Skin and eye: uncommon sites of distant metastasis from tongue base squamous cell carcinoma

The frequency of non-lymphatic distant metastases from primary head and neck squamous cell carcinoma (SCC) appears to be higher than previously presumed. The general conditions of the affected patients, who usually also present with locoregional recurrences, are so impaired as to limit the use of available methods for diagnosing the distant spread of head and neck SCC. The incidence reported in autopsy studies is approximately three to four times higher than that in clinical studies. Lung metastases from head and neck SCC are most common, followed by metastases to bone and liver. Metastases to the skin are unusual. Secondary ocular localizations of head and neck SCC are exceedingly rare. We report the first case of synchronous intraocular (involving the choroid and vitreous body) and cutaneous metastases from a recurrent tongue base SCC in a 64-year-old woman who had undergone radiotherapy, bilateral neck dissection and chemotherapy. Cytological evaluation of vitreous aspirate and histological diagnosis of the skin lesion were performed < 1 month before the patient's death. Skin metastases occur in 1-4% of patients with diagnosed head and neck SCC and are usually associated with advanced or recurrent disease. To the best of our knowledge, fewer than 10 cases of ocular metastases from head and neck SCC have been reported. The average survival time after diagnosis of ocular or skin metastases from head and neck SCC is 7 months. Treatment for eye and skin metastases is palliative and rarely alters patient outcome.     

Laryngeal leiomyosarcoma

We report one case of leiomyosarcoma (LMS) of the larynx occurring in a patient with a history of immunosuppressive therapy, and offer a critical review of the literature. Epstein-Barr virus (EBV) genome was not identified in the neoplastic cells. The patient was treated with endoscopic resection and post-operative radiotherapy. Lung metastasis and thyroid infiltration became evident 14 months following treatment despite the absence of laryngeal recurrence. Progressive decline occurred and the patient died 15 months after diagnosis.     

Eating in larger groups increases food consumption

OBJECTIVE: To determine whether children's food consumption is increased by the size of the group of children in which they are eating. DESIGN: Crossover study. SETTING: University based preschool. PARTICIPANTS: 54 children, aged 2.5-6.5 years. INTERVENTIONS: Each child ate a standardised snack in a group of three children, and in a group of nine children. MAIN OUTCOME MEASURES: Amount each individual child consumed, in grams. RESULTS: Amount eaten and snack duration were correlated (r = 0.71). The association between group size and amount eaten differed in the short (<11.4 min) versus the long (> or =11.4 min) snacks (p = 0.02 for the interaction between group size and snack duration). During short snacks, there was no effect of group size on amount eaten (16.7 (SD 11) g eaten in small groups vs 15.1 (6.6) g eaten in large groups, p = 0.42). During long snacks, large group size increased the amount eaten (34.5 (16) vs 26.5 (13.8), p = 0.02). The group size effect was partially explained by a shorter latency to begin eating, a faster eating rate and reduced social interaction in larger groups. CONCLUSIONS: Children consumed 30% more food when eating in a group of nine children than when eating in a group of three children during longer snacks. Social facilitation of food consumption operates in preschool-aged children. The group size effect merits consideration in creating eating behaviour interventions.     

Volumetric rendering of MR images

The authors developed new techniques for three-dimensional display of magnetic resonance (MR) images that preserve soft-tissue definition, are fully automatic, and work with routinely used section thicknesses. MR images are segmented, selectively enhanced, and displayed by means of a volumetric rendering algorithm. These techniques were used to illustrate normal anatomy of the brain, knee, and liver. Three-dimensional rendering of balanced spin-echo images shows the ventricles and extracerebral veins and of T1-weighted images, the sulci and gyri. The large hepatic and portal vessels can be seen with these enhancement techniques. Three-dimensional views of the knee reveal articular surfaces of the tibia and clearly depict menisci and posterior and anterior cruciate ligaments. These techniques make it possible to image multiple soft tissues simultaneously while preserving the detail contained in the original images. Three-dimensional presentation of complex, overlapping anatomic regions is helpful in surgical planning and should lead to improved diagnosis.     

Digital beam attenuator technique for compensated chest radiography

The feasibility of producing patient-specific beam attenuators for chest radiography has been investigated using an anthropomorphic phantom and a human volunteer. A low-dose test exposure is digitized, processed, and used to print a small cerium filter, which is placed in the x-ray beam near the collimator. The final radiograph is recorded on film. The technique results in relatively uniform film exposure, so that structures in all regions of the chest are simultaneously displayed with optimal film contrast. The equalized exposure improves image quality in the normally underpenetrated regions and reduces the role of cross-scatter from the lungs. The image is analogous to optical or computer-processed unsharp masking techniques, but the processing is accomplished in the x-ray beam and results in an improved exposure distribution, giving advantages that cannot be achieved with image processing techniques alone.