Central Nervous System and Head and Neck Histiocytoses: A Comprehensive Review on the Spectrum of Imaging Findings.

The histiocytoses are a rare group of varied but related disorders characterized by abnormal tissue proliferation of macrophages and dendritic cells within tissues. The purpose of this article was to review the imaging findings in patients presenting with CNS and with head and neck manifestations of these disorders. Histiocytoses include but are not limited to Rosai-Dorfman disease, Erdheim Chester disease, Langerhans cell histiocytosis, histiocytic sarcoma, and juvenile xanthogranuloma. A review of the literature was performed to determine the sites of disease involvement. This article includes the demographics, histopathologic criteria for diagnosis, and imaging features of these histiocytoses, and describes the manifestations in locations known to harbor disease: intraaxial and extra-axial intracranial regions, the calvaria, skull base, hypothalamopituitary axis, orbits, paranasal sinuses, spine, and the head and neck region. Histiocytoses have variable imaging appearances in the CNS and in the head and neck region, and radiologists should be aware of the spectrum of findings to avoid mistaking them for other disease processes. LEARNING OBJECTIVE: To understand the general pathophysiology, clinical presentation, and typical imaging characteristics of the most common histiocytoses; comprehend the morphologic and immunohistochemical characteristics of these histiocytoses and the hallmark findings on pathology; and be able to differentiate between these disorders based on their most common presentations.

Shy / silent users of contraceptives in Pakistan.

PIP: This study examines the hypothesis that shy, silent users of contraceptives in Pakistan underreport contraceptive usage. Data were obtained from the 1984-85 and 1994-95 Contraceptive Prevalence Surveys, the 1990-91 Demographic and Health Survey, and a Punjab 1993 survey. The data were reorganized to indicate the number of women who were fecund but did not have a birth within the preceding 5 years before the surveys. 698,864 women in 1984-85 did not have children and did not report contraceptive use, or 5.9% of total respondents. If these women were added to the contraceptive prevalence rate (CPR), it would rise from 7.6% to 13.5%. The higher CPR is consistent with the observed total fertility rate of 5.95. Shy or silent users were 11.9% in 1990-91 and 11.3% in 1994-95. The revised CPRs are 23.7% and 29.1%, respectively. In 1993, a follow-up survey among non-users in Punjab province showed that CPR increased from 13% in 1990-91 to 18% in 1993. Withdrawal was the most widely used method, followed by the condom and female sterilization. The increase in CPR is attributed to more open reporting among shy or silent users. Revised CPRs that include shy or silent users were consistent with total fertility rates in all 3 nationally representative surveys. Typically shy or silent users were older by about 2.3 years than current users, but had similarly aged husbands. Shy or silent users had longer duration of marriage, greater illiteracy, and less contraceptive knowledge about methods and sources. Shy or silent women had lower children ever born rates than current users.^ieng

Comments on "An Indirect View of the Fertility Changes in Pakistan".

PIP: The comments made about the study of fertility change in Pakistan focused on the issues of data reliability and affirmed the results concerning the impact of demographic and socioeconomic factors on fertility decline. The benefits of using life table analysis to generate crude birth rates (CBRs) independent of birth data were recognized. The decline in fertility was obvious. The appropriateness of the selection of data used to estimate CBRs was questioned. Reporting errors were evident for under 5 year mortality data used in the life table estimation. Life table methods were used do help smooth some of the variation in figures, but the preference was for reliable data or satisfactory values for social and economic variables. In spite of the data limitations, the authors were commended for providing an adequate presentation of data on declining fertility in Pakistan. The National Institute of Population Studies will be addressing the needs of researchers for better quality data on birth rates, death rates, and contraceptive prevalence rates. Comparability between series constructed between 1962 and 1990 restricted analyses, but the analyses supported the changing trends. Age of marriage has increased to over 21 years. Contraceptive prevalence and per capita income have risen. Female literacy is slowly rising. Total fertility in 1990-91 from the Demographic and Health Survey was around 5.2 to 5.4. However, UN figures showed fertility of 5.9, which was probably based on figures adjusted from data in the 1984-87 Demographic Survey.^ieng

Shy/silent contraceptive users: further evidence.

PIP: The National Institute of Population Studies analyzed data on 6364 currently married women from the 1990-1991 Pakistan Demographic and Health Survey (PDHS) to confirm the hypothesis (developed after analysis of the 1984-1985 Contraceptive Prevalence Survey) that contraceptive use was underreported, more so than births, due to shyness. The reported contraceptive prevalence rate (CPR) was 11.8%. Further analysis suggested that 11.9% (759) of currently married women were indeed shy/silent users, defined as women who had not given birth in the last 5-7 years, had not experienced menopause, reported to not be using any contraceptives, had at least 1 child, were less than 45 years old, and did not have secondary infertility. They comprised 44.1% of all nonpregnant nonusers. If one adds the shy/silent users to the contraceptive prevalence rate, it becomes 23.7% (11.8 + 11.9%). The expected total fertility rate (TFR) for a CPR of 11.8% was 6.1. Using the Bongaarts regression intercept of 6.83 and the CPR that includes the shy/silent users resulted in better consistency between the reported PDHS TFR (5.2-5.4) and the adjusted CPR (23.7%). The shy/silent users were more likely to be older (37.1 years vs. 34.8 years), married longer (e.g., married for 20 years, 50.3% vs. 33.4%), and illiterate (83.5% vs. 52%) and to depend more on Allah when expressing a desire for more births (16.8% vs. 2.1%) than the reported current users. They were less likely to believe their husbands approved on contraception (21.1% vs. 57.4%), to talk to them about family planning (16.2% vs. 44.4%), and to be able to go to health facilities and family planning clinics alone (25.4% vs. 50.4%). These findings suggested that the shy/silent users were doing something to prevent pregnancy. They may not have been using modern contraception, but probably used traditional methods and induced abortion. Additional research should examine what methods these women do indeed use to prevent births.^ieng

Trends in the growth of population and labour force in Pakistan.

PIP: Trends in the growth of the population and labor force in Pakistan are examined and future prospects for growth of population and labor, particularly agriculture, are estimated. The definition of labor force as employed or seeking work after a short period of employment has led to a great disparity in results for women in the labor force. Past trends in population growth reflected a growth rate of 1.6% for the 1950's, and 2.4% in 1960. The population rose to 84.3 million in 1981 from 42.6 million in 1961, which intercensally was an increase of 3.6% per annum for 1961-72 and 3.1% per annum for 1972-81. The estimated rate for 1981-86 was 2.9%/year. The rural population doubled and the urban tripled. There was a net migration of 2.123 million to urban areas reported in the 1981 census. There is also evidence of a high sex ratio. Balochistan (7.1%) and Sindh (3.6%) provinces have the highest growth rates. Although the largest population is in the Punjab, the growth is the lowest at 2.7%. The population is primarily young -- 44.5% 15 years in 1981, which is the highest in the world. Under high, medium, and low levels of fertility, prospective trends are estimated for 2006 and 2031, and by sex every 5 years from 1981. Population under high fertility is expected to reach 270 million by 2031, which is 3.39 persons/hectare. The population/hectare of land under cultivation was 4.25 in 1981 and is expected to rise to 13.49 persons/hectare in 2031. 11 million acres could be brought under cultivation to reduce the ratio. However, there are ecological considerations as well as an employment problem. The dependency ratio under the high variant will decline from 76.8 persons 0-14 and 65 years/100 persons 15-64 years in 1986 to 70.3 in 2006 which is still considerably higher than other developing countries. It is suggested that replacement level fertility be attained as soon as possible. Under low fertility, replacement level can be reached by 2011 with strong political commitment. Past trends in the labor force, employment and unemployment, and employment by major industry are reported. The labor force participation rate of 29.6% in 1985 is among the lowest in the world. The age structure of the population, inadequate human resource development, and underreporting of females in the labor force account for the low rates. Population grew by 96.5% between 1961 and 81, but labor force increased 77.3% and employment 74.4%. The greatest growth was in the nonagricultural sector. Prospective trends show agricultural labor force growing from 15.1 million in 1981 to 20.2 million in 2006, which is expected to put pressure on agricultural land. Female nonagricultural sector labor force is expected to grow due to increased literacy and fertility declines.^ieng

Comments on "Some Considerations for Demographic Assessment of Developing Countries".

PIP: The momentum of population growth in developing countries, the advent of systematic planning for social and economic development, and political independence have all contributed to an awareness of the need for demographic assessment. An increase in the proportion of female population of reproductive age begins to take place as a result of fertility decline that reduces the proportion of children under 15 years of age. If fertility continues to decline until it reaches the replacement level, population will continue to grow for another 40-50 years before zero population growth is achieved. Despite efforts to integrate demographic variables within the development planning process, population is still being considered as an exogenous variable. Needed is more sophisticated, intensive research aimed at identifying the variables (both direct and indirect) in the population-development interrelationship. While censuses have significantly improved as a result of political independence, vital registration systems have not shown any progress in producing usable data for demographic analysis. For demographic assessment to become a reality, there is an urgent need to improve gaps in the availability of current, reliable data.^ieng