Brachytherapy for HGGs includes the temporary use of high-activity implants and permanent placement of lower-activity sources. Early reports on the use of brachytherapy with temporary high-activity implants were encouraging, but subsequent re-evaluation showed that much of the treatment effect was due to selection bias [33]. Subsequent randomized prospective trials of interstitial, high-activity, temporary I-125 implants, used as a boost at the time of initial treatment, have reported contradictory results. Permanent low-activity I-125 implants placed at initial operation have produced promising results but require additional validation.

Similar brachytherapy strategies using either high-activity I-125 temporary, or low-activity I-125 permanent, implants have been used for HGGs at the time of recurrence. While the efficacy of these approaches is not clearly established, one study reported the survival of patients receiving permanent implants was almost two-fold longer than a comparable group of historical controls treated aggressively with surgery and chemotherapy. One consideration in their use is that treatment-related morbidity appears to be less for permanent low-activity implants than for temporary high-activity implants. One difficulty with any brachytherapy approach is achieving uniform dose distributions to all involved regions of tumor. Dose heterogeneity can lead to under-treated (cold spots) or over-treated areas (hot spots) at risk for rapid progression or radiation injury and necrosis, respectively. While the use of stereotactic radiation techniques provides boosts with more defined dosimetry, it is often difficult to shape the radiation field to the irregular growth patterns of most HGGs.

Cure Your Yeast Infection For Good

Cure Your Yeast Infection For Good

The term vaginitis is one that is applied to any inflammation or infection of the vagina, and there are many different conditions that are categorized together under this ‘broad’ heading, including bacterial vaginosis, trichomoniasis and non-infectious vaginitis.

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