The importance of DHT in causing nodular hyperplasia is supported by clinical observations in which an inhibitor of 5α-reductase such as finasteride is given to men with this condition. Therapy with a 5α-reductase inhibitor markedly reduces the DHT content of the prostate and, in turn, reduces prostate volume and BPH symptoms.Testosterone promotes prostate cell proliferation, but relatively low levels of serum testosterone are found in patients with BPH. One small study has shown that medical castration lowers the serum and prostate hormone levels unevenly, having less effect on testosterone and dihydrotestosterone levels in the prostate.While there is some evidence that estrogen may play a role in the cause of BPH, this effect appears to be mediated mainly through local conversion of androgens to estrogen in the prostate tissue rather than a direct effect of estrogen itself. In canine in vivo studies castration, which significantly reduced androgen levels but left estrogen levels unchanged, caused significant atrophy of the prostate. Studies looking for a correlation between prostatic hyperplasia and serum estrogen levels in humans have generally shown none.In 2008, Gat et al. published evidence that BPH is caused by failure in the spermatic venous drainage system resulting in increased hydrostatic pressure and local testosterone levels elevated more than 100 fold above serum levels. If confirmed, this mechanism explains why serum androgen levels do not seem to correlate with BPH and why giving exogenous testosterone would not make much difference.
Congenital cystic eye (also known as CCE or cystic eyeball) is an extremely rare ocular malformation where the eye fails to develop correctly in utero and is replaced by benign, fluid-filled tissue. Its incidence is unknown, due to the very small number of cases reported. An audit by Duke-Elder of the medical literature from 1880 to 1963 discovered only 28 cases. The term was coined in 1937 by the renowned ophthalmologist Ida Mann.Embryologically, the defect is thought to occur around day 35 of gestation, when the vesicle fails to invaginate. Dysgenesis of the vesicle later in development may result in coloboma, a separate and less severe malformation of the ocular structures. CCE is almost always unilateral, but at least 2 cases of bilateral involvement have been described. Patients may also present with skin appendages attached to the skin surrounding the eyes. Association with intracranial anomalies has been reported. Treatment
Treatment of CCE is usually by enucleation, followed by insertion of an ocular implant and prosthesis. References


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