Pathological changes in the diameters of the lumbar spinal canal may be associated with low back pain. The assessment of the size of the canal is therefore an important diagnostic procedure. Evidence suggests that there are ethnic differences in the dimensions of the canal. A radiogrammetric study was therefore undertaken to establish norms of the transverse diameter for the Saudi population. The results show that the transverse diameter of the canal in Saudis differs from that of other populations but the shape is similar to those of earlier reports. Intersegmental differences which are useful for the detection of isolated segmental anomalies were also calculated. The significance of the findings is discussed.

The lumbar spinal canal may become narrowed as a result of a congenital defect (developmental stenosis) or following other changes associated with the vertebral column or its related structures (acquired stenosis). Stenosis of the canal may predispose the roots of the cauda equina to pressure or entrapment and consequently cause low back pain. Evidence suggests that the sagittal diameter is probably more frequently involved in stenotic lesions. Measurement of diameters from plain radiographs have been shown to yield valuable diagnostic information. In view of the diversity of shape and sizes in the human lumbar spinal canal, norms are needed for individual populations.In the present study, plain lateral radiographs of 150 male and 150 female adult Saudi subjects were measured. The mean sagittal diameters and standard deviations of lumbar levels L1 to L5 are reported for the first time within this population. A reliable method of delimiting the posterior boundary of the canal has also been described. The pattern of segmental variation of the diameters of the lumbar canal in normal adult Saudis was found to be similar to that in other populations, but the mean diameters were different. Norms of the canal: body ratio were also established for use in rapid evaluation of patients.

A detailed radiologic and anatomic study of a 20-week-old fetus is presented. In addition to conventional radiography, various contrast medium injection techniques were used. The findings were followed up at autopsy. The fetus showed multiple congenital abnormalities comprising phocomelia, horseshoe lung, horseshoe kidney, urethral stenosis with megacystis, bilateral hydronephrosis, hydrourcters, imperforate anus, and a single tracheo-esophageal tube· (persistent esophago-trachea). The association of horseshoe lung with persistent esophago-trachea, microurethra, megacystis, bilateral hydroureters, hydronephrosis and phocomelia is, we believe, the first ever to have been recorded in the literature. Twenty-one cases of horseshoe lung have been reported in the literature. These cases were reviewed and a comparison with the present case is presented. The embryologic basis for these anomalies is also briefly discussed.

2% glyoxylic acid buffered to pH 7 could be used to improve the localization of cholinergic, adrenergic and nonspecific nerve profiles both in frozen sections and stretch preparations. The results are better than those obtained by conventional techniques, exhibiting the distinct reactions, with the least possible background and diffusion. The results are quickly obtained.

Thirty-three cases of 1,500 spontaneously-aborted foetuses showed hepatic calcifications. The exact location of these calcifications were confirmed by contrast studies, anatomic dissection, and further histology when necessary. Of them, 18 were calcified hepatic vein thrombi (CHVT), 12 were calcified portal vein thrombi (CPVT), 2 were parenchymal calcifications, and one was mixed. Associated anomalies were high (85% of cases). No significant difference was found between the type and percentage of anomalies of those with CHVT and those with CPVT. The most common anomalies encountered in all cases were meconium intraluminal calcification (27%), cystic hygroma (18%), and metaphyseal defect (18%). In view of this, it is suggested that a variety of severe foetal illnesses predispose to CHVT and CPVT. At correlation with maternal factors, it was found that the highest incidence was in the third decade. A significant high percentage of mothers (33%) had been on contraceptive pills, and there was interesting inverse relationship of hepatic calcification with gravidity. Practically, it is also hoped that the awareness of the presence of various types of hepatic calcifications will help in their detection prenatally by ultrasound.