Chemical ablation

The equivalent procedure for the main olfactory epithelial sheet (MOEx) is chemical ablation by treatment with (5%) zinc sulphate solution. The adoption of this approach was determined by practical anatomy, given the inevitably partial, let alone traumatic, results of cutting/scraping epithelia from the intricately folded sensory surfaces (Negus, 1958). 

The creation of reactive species that cause ablation is essentially the same process as that occurs in LCVD, except that the final result is completely opposite, i.e., ablation vs. deposition. In this context, ablation by luminous gas could be described as luminous chemical vapor treatment (LCVT). Therefore, the dependence of ablation on operational parameters in LCVT is very similar to that of LCVD, which is discussed in more detail in Chapter 4. The chemical ablation of polymeric materials by O2 plasma [6] is described here to demonstrate how oxidative ablation is influenced by the operational parameters of discharge. 

Lieberman DM, Corthesy ME, Cummins A, Oldfield EH. Reversal of experimental parkinsonism by using selective chemical ablation of the medial globus pallidus. J Neurosurg 1999 90 928-934. 

In general, tumor ablation can be divided into two main categories. The first one is chemical ablation, the second one is thermal ablation. Additionally, other interventional oncological therapeutic approaches have to he defined, such as the percutaneous dehvery of radioactive seeds and the transcatheter delivery of chemotherapy and chemoemho-lization. 

Chemical ablation is classified based on the used agent, such as ethanol, or acetic acid. By definition, chemical ablation induces coagulation necrosis and tumor ablation. Ethanol ablation is also called percutaneous ethanol instillation (PEI), percu-... 

Clark TWI, Soulen MC (2002) Chemical ablation of hepatocellular carcinoma. J Vase Interv Radiol 13 S245-S252... 

These disappointing results coupled with the poor response of HCC to traditional chemotherapy have provided the impetus for the development of a variety of nonsurgical techniques for the treatment of hepatic neoplasms (Table 10.1). Such techniques are generally divided into transarterial interventions versus percutaneous ones. The latter group is further subdivided into thermal ablation techniques versus chemical ablation techniques. 

Thermal ablation Chemical ablation TACE TARE... 

Chemical ablation is an effective tool for studying nervous system development and function in Drosophila. The only substance currently used for this purpose in flies is hydroxyurea (HU), an inhibitor of ribonucleotide reductase that blocks DNA synthesis and kills... 

The advantages of HU as an agent for chemical ablation are derived from its biological activity. Relatively low doses of HU can be administered orally (de Belle and Heisenberg 1994 see below) or by injection (Truman and Booker 1986 Prokop and Technau 1994). Within approximately 3 hours, HU accumulates to maximum concentrations in tissues and is metabolized to an inactive molecule approximately 1 hour thereafter (Timson 1975). The lethal effects of HU are only realized in dividing cells. All remaining cells are held synchronous in the Gj phase of the cell cycle until metabolism of HU is complete. 

Truman J.W. and Booker R. 1986. Adult-specific neurons in the nervous system of the moth, Manduca sexta Selective chemical ablation using hydroxyurea. /. Neurobiol. 17 613-625. 

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