Premature ovarian insufficiency: from pathogenesis to clinical management.

Premature ovarian insufficiency (POI) represents a condition characterized by the absence of normal ovarian function due to an incipient (by 3-10 years) ovarian aging. In most of the women affected there are no signs or symptoms that precede the interruption of menstruation and the onset of POI and the majority of women have a normal history of menarche, regular menstrual cycles and normal fertility. The possible genetic role in the development of POI has been largely demonstrated and many genes have been involved; on the other hand, ovary is not protected immunologically and the detection of autoantibodies directed against various ovarian targets strongly support the hypothesis of an autoimmune etiology. In approximately 5-10% of women with a diagnosis of POI with a normal karyotype, a spontaneous pregnancy could occur even if the recovery of ovarian function is temporary and poorly predictable. Embryo donation and adoption are other alternatives that should be considered. POI and subsequent loss of reproductive capacity is a devastating condition and a difficult diagnosis for women to accept so it requires an individualized and a multidisciplinary approach. Hormonal replacement therapy (HRT) should be commenced as soon as possible to prevent and to contrast the onset of the symptoms related to hypoestrogenism and to improve the quality of life for these women.

Clinical use of placental hormones in pregnancy management.

Across human pregnancy, placenta represents a transit of oxygen and nutrients from the mother to the fetus and actively produces a large number of hormones that serve to regulate and balance maternal and fetal physiology. An abnormal secretion of placental hormones may be part of the pathogenesis of the main obstetric syndrome, from early to late pregnancy, in particular chromosomopathies, miscarriage, gestational trophoblastic diseases, preeclampsia, gestational diabetes, and pre-term delivery. The possibility to measure placental hormones represents an important tool not only for the diagnosis and management of gestational disorders, but it is also fundamental in the early identification of women at risk for these pregnancy complications. In the last decades, the use of ultrasound examination has provided additional biophysical markers, improving the early diagnosis of gestational diseases. In conclusion, while few placental hormones have sufficient sensitivity for clinical application, there are promising new biochemical and biophysical markers that, if used in combination, may provide a valid screening tool.

Genes involved in the pathogenesis of premature ovarian insufficiency.

Premature ovarian insufficiency (POI) is defined by the presence of primary or secondary amenorrhea, for at least 4 months, before the age of 40 years associated with follicle stimulating homone levels in menopausal range, exciding 40 UI/L. The diagnosis is confirmed by two blood sample at least 1 month to measure the level of FSH (over 40 UI/L) and level of estradiol (below 50 pmol/L). Ovarian follicular dysfunction and/or depletion of functional primordial follicles characterized this pathology. Abnormal bleeding patterns also include oligomenrrhea and polimenorrhea; because of these irregular menstrual cycles during adolescence, diagnosis could be difficult in young women. Excluding the cases in which an etiopathogenetic agent could be identified, such as in case of chemio- and radiotherapy or extensive surgery, women with autoimmune diseases and/or infections, the etiology of POI remains idiopathic. An important genetic component exists, supported by both a frequent recurring familiar event (20-30%) and the association with other different genetic disorders in particular the X chromosome defects and the implication of some different genes with significant functions in ovarian development. For most of the women the diagnosis of POI is unexpected because of there are no obvious signs or symptoms that precede the cessation of periods with a normal menstrual history, age of menarche and fertility prior to the onset of menopause. The diagnosis of POI has a deleterious psychological impact on the emotional sphere of the women affected: anger, depression, anxiety and sadness are common and the fact that the diagnosis coincides with infertility needs a psychological support. Oral hormonal replacement therapy (HRT) administration is not recommended as first choice of treatment because of the higher hormones concentration with respect to the real hormones necessity of the patients and transdermal HRT may be preferred in women with coagulation disturbances to relief symptoms and to improve to quality of life and the sexuality of these women until the age of 50 years old which is the median age of physiological menopause. Moreover it should be considered the associate comorbidities of POI such as bone loss, cardiovascular disease and endocrine disease.

[The interactions between metal stapes prostheses and high-intensity magnetic fields during magnetic resonance tomography]. / Interazioni tra protesi stapediali metalliche e campi magnetici di elevata intensità in corso di tomografia a risonanza magnetica.

The ever-increasing use of magnetic resonance tomography (MR) as an investigation mean has created a new interest in the biological effects of magnetic fields (MF) and in finding protective measures to be taken in their event. At the moment, use of MR is contraindicated in the presence of pacemakers, vascular clips, liquoral shunts and orthopedic prostheses, all of which may be dislocated by the MF created by MR or may interact with the MF itself creating distorted or falsified images. The aim of our study was to verify if metallic stapedectomy prostheses are dislocated by the MF and if they produce enough interference to falsify MR images. Five types of metallic stapedial prostheses exposed to a MF of 0.5T were studied. We may conclude from our results that MR does not create any otological risks for patients with these prostheses in that none of them were dislocated during exposure. However, all the prostheses studied did instead bring about alterations in the MF and the MR image to varying degrees. In some cases (Robinson) there was notable image distortion, while in others (Schuknecht wire teflon and platinum piston) the distortion was practically negligible. It is our opinion, however, that even if the image distortion does not interfere with routine MR, use of prostheses made of materials not affected by MF are advisable in view of an eventual development of visualization of the labyrinth and intratemporal facial nerve portion with MR.