The query corner

An improved version of the MPT2 (LAUDA) computerized tensiometer (Germany) was used to measure dynamic surface tension (ST) of blood and urine by the maximum bubble pressure method in patients with tumors of the uterus, vagina and cervical canal. Relatively low blood and urine ST values at t-->infinity and serum at t = 1 s were registered. Combined radiotherapy involved oppositely-directed changes in the equilibrium (static) ST of the biological fluids as well as a urine ST inhibition in the surface short-life range (t = 0.01 s). The slope of blood serumtension curves by the end of treatment was close to that in healthy females.     

Design of an Arabic near visual acuity chart

This paper describes the design of an Arabic test chart for measurement of visual acuity at near. The chart was designed employing specially selected Arabic letters and was based on the logMAR principle devised by Bailey and Lovie. Ten Arabic letters of nearly equal legibility values (0.92-1.05) (mean = 1.00), (SD = 0.05) were used in the design of the chart. Each row of the chart has 5 letters and row legibility values range from 4.82 to 5.03 with a mean of 4.92 (SD = 0.06). The logMAR method of visual acuity scaling was used, hence the sizes of letters in the rows progress in a uniform step of 0.1 log unit. The inter-letter spacing is equal to the width of each letter in the row, while inter-row spacing is equal to the height of letter in the subjacent row. The height of letters ranged from 3.67 to 0.46 mm corresponding to visual acuity of 2.4 M to 0.3 M which is equivalent to reduced Snellen 6/36 to 6/4.5 at 0.4 m. The chart is designed for use at 40 cm with a recommended luminance level of 160 cd/m2.     

The query corner. Contrast-medium-induced nephropathy

The process of clerking routine pre-operative admissions involves the house officer taking a full medical history and performing a full physical examination. The diagnostic yield is thought to be low, and the educational value to the house officer is also small. This study addresses the question as to whether routine physical examination is always indicated. One hundred and nine children admitted for routine Otolaryngology procedures were prospectively studied to identify the importance of examination in the pre-operative assessment of patients. The results showed that 51 per cent of the children admitted had risk factors. The medical history was sufficient to identify these risk factors in all patients with the exception of one cardiac condition. This study concludes that a suitable alternative to the current process of clerking such as a standardized nurse history could be safely and efficiently undertaken. Eliminating the tiny percentage of previously unrecognized disease would be a prerequisite for such a change.     

Physical abuse of children: an update

Now, more than ever, physicians must be willing to suspect child abuse and report their concerns. New information from the past decade warns us that reports of violence against children continue to increase. We are learning that MRI imaging of the head may, in some cases, help date subdural hematomas, but long-term developmental follow-up studies of "shaken" infants are lacking. Intentional thoracic and abdominal injuries carry a high mortality. Finally, new information in the field of child abuse-in particular, physical abuse-is slow to come. Lack of funding for basic medical child abuse research and lack of trained researchers in the field are the two most important barriers. Preventive intervention at the community and family level needs to be supported by both the pediatrician and the local and national government leaders. As the U.S. Advisory Board on Child Abuse and Neglect says, "We need to make it as easy for parents to pick up the telephone and get help before they abuse their child as it is now for their neighbor or physician to pick up the telephone and report them after it has happened." Child health practitioners may be in the best position to implement such a policy.     

Surgical weakening of the inferior oblique

1. The inferior oblique may be weakened effectively by recession, disinsertion, or myectomy, disrupting the muscle continuity between Lockwood's ligament and the muscle's insertion. 2. A successful unilateral inferior oblique weakening produces 20 prism diopters less hypertropia or more hypotropia in the field of action and has less effect away from the muscle's field of action; a bilateral weakening of the inferior oblique produces 20 prism diopters less exotropia or more esotropia in upgaze. 3. Complications of inferior oblique weakening are persistent overaction, operation on the wrong muscle, and the adherence syndrome. 4. The adherence syndrome is not related to the myectomy procedure specifically but is probably related to (or caused by) fat rupture with hemorrhage, which may accompany any type of inferior oblique weakening. 5. The adherence syndrome can be avoided by careful surgical technique.