Impact of target point deviations on control and complication probabilities in stereotactic radiosurgery of AVMs and metastases.

OBJECTIVE: Determination of the impact of inaccuracies in the determination and setup of the target point in stereotactic radiosurgery (SRS) on the expectable complication and control probabilities. METHODS: Two randomized samples of patients with arteriovenous malformation (AVM) (n=20) and with brain metastases (n=20) treated with SRS were formed, and the probability for complete obliteration (COP) or complete remission (CRP), the size of the 10 Gy-volume in the brain tissue (VOI10), and the probability for radiation necrosis (NTCP) were calculated. The dose-effect relations for COP and CRP were fitted to clinical data. Target point deviations were simulated through random vectors and the resulting probabilities and volumes were calculated and compared with the values of the treatment plan. RESULTS: The decrease of the relative value of the control probabilities at 1mm target point deviation was up to 4% for AVMs and up to 10% for metastases. At 2 mm the median decrease was 5% for AVMs and 9% for metastases. The value for the target point deviation, at which COP and CRP decreased about 0.05 in 90% of the cases, was 1.3 mm. The increase of NTCP was maximally 0.0025 per mm target point deviation for AVMs and 0.0035/mm for metastases. The maximal increase of VOI10 was 0.7 cm(3)/mm target point deviation in both patient groups. CONCLUSIONS: The upper limit for tolerable target point deviations is at 1.3mm. If this value cannot be achieved during the system test, a supplementary safety margin should be applied for the definition of the target volume. A better accuracy level is desirable, in order to ensure optimal chances for the success of the treatment. The target point precision is less important for the minimization of the probability of radiation necroses.     

Risk factors for postpartum depression: a retrospective investigation

OBJECTIVE: To search for a possible correlation between incidence of postpartum depression (PPD) and any of the following factors recorded in patient charts at the routine, 4-week postnatal visit: age, breast-feeding status, smoker/nonsmoker, marital status, preexisting depression and type of delivery. STUDY DESIGN: Data were obtained from 588 obstetric charts for women who gave birth between June 1, 2003, and June 1, 2004, at 3 university clinics in Tulsa, Oklahoma. RESULTS: Prior history of depression and smoking cigarettes were significant risk factors for an Edinburgh Postnatal Depression Scale score of 13 or higher, indicating probable PPD. CONCLUSION: Our data and previous findings warrant continued investigation in a larger study to clearly delineate these and other possible risk factors for PPD and to facilitate prophylactic patient education and intervention strategies.     

The role of apical vaginal support in the appearance of anterior and posterior vaginal prolapse

OBJECTIVE: To describe how simulated apical support affects the appearance of prolapse in the anterior and posterior vagina using a modification of the Pelvic Organ Prolapse Quantification (POP-Q) examination. METHODS: Women with prolapse stage II or greater were examined using the POP-Q. To simulate apical support, the posterior blade of a standard Graves speculum was positioned over the posterior vagina to support the vaginal apex while remeasuring points Aa and Ba and over the anterior vagina to support the apex while remeasuring points Ap and Bp. Change in anterior and posterior POP-Q points and prolapse stage with apical support were calculated. RESULTS: One hundred ninety-seven women were enrolled with mean age of 62+/-14 years, median parity of 2 (range 0-8), and mean body mass index of 28+/-5 kg/m(2). By standard POP-Q, 36% had stage II prolapse, 54% had stage III, and 10% had stage IV prolapse. With simulated apical support, point Ba changed to stage 0 or I in 55% of cases and point Bp changed to stage 0 or I in 30% (P<.001 for each point). Mean change for point Ba with apical support was 3.5+/-2.6 cm and point Bp was 1.9+/-2.9 cm (P<.001). CONCLUSION: When the POP-Q examination is performed with simulated apical support, the critical role of level I vaginal support on the position of the anterior and posterior vagina, particularly the anterior vagina, becomes apparent. LEVEL OF EVIDENCE: II.     

Meiotic errors in human oogenesis and spermatogenesis

Chromosome anomalies are extraordinarily common in human gametes, with approximately 21% of oocytes and 9% of spermatozoa abnormal. The types of abnormalities are quite different since most abnormal oocytes are aneuploid, whereas the majority of abnormalities in spermatozoa are structural. Chromosomes 21 and 22 (the smallest chromosomes) are over-represented in aneuploid gametes in both oocytes and sperm. Chromosome 16 is also frequently observed in aneuploid oocytes, whereas the sex chromosomes are particularly predisposed to non-disjunction in human sperm. Maternal age is clearly the most significant factor in the aetiology of aneuploidy; theories about the cause of the maternal age effect are discussed. Paternal age does not have a dramatic effect on the frequency of aneuploid sperm; there is some evidence for a modest increase in the frequency of sex chromosomal aneuploidy. Meiotic recombination has a significant effect on the genesis of aneuploidy in both females and males. New techniques, which allow the analysis of recombination along the synaptonemal complex, have yielded interesting new information in healthy and infertile individuals. There is a link between infertility and the genesis of chromosome abnormalities. Future studies will unravel more of the underlying causal factors.     

Blastocyst development after sperm selection at high magnification is associated with size and number of nuclear vacuoles

Spermatozoa selection at high magnification before intracytoplasmic sperm injection seems to be positively associated with pregnancy rates after day 3 embryo transfers. The aim was to demonstrate an association between the presence of vacuoles in sperm nuclei and the competence of embryos to develop to day 5. Grading of spermatozoa at x 6000-x 12,500 magnification: grade I, no vacuoles; grade II, or=1 large vacuole; grade IV, large vacuoles with other abnormalities. The outcome of embryo development in a group of 25 patients after sibling oocyte injection with the four different grades of spermatozoa showed no significant difference in embryo quality up to day 3. However, the occurrence of blastocyst formation was 56.3 and 61.4% with grade I and II spermatozoa respectively, compared with 5.1% with grade III and 0% with grade IV respectively (P < 0.001). Spermatozoa selection at high magnification using Nomarski interference contrast is useful to identify more precisely the size and the number of nuclear vacuoles that greatly exert a negative effect on embryo development to the blastocyst stage. These observations confirm previous studies pointing to possible 'early and late paternal effects', both of which may have an impact on early embryonic development.