The growth of T lymphocytes is dependent on the T-cell growth factor interleukin 2 (IL-2), which causes T cells bearing high-affinity receptors for IL-2 to proliferate. Most cloned helper-T-cell lines can be shown to both produce and respond to IL-2; thus, growth of such cells is by an autocrine mechanism. We report that the failure of the cloned murine T-cell line D10.G4.1 to respond to its own IL-2 results from the secretion, by the same cells, of a potent inhibitor of the IL-2-driven T-cell proliferative response. This inhibition can be overcome by increasing the number of IL-2 receptors expressed by the target cell. In the cloned T-cell line producing the inhibitory substance, this increase in IL-2 receptors is driven by the monokine interleukin-1. We propose that this inhibitor of IL-2 responses may play a role in preventing "bystander" activation of T cells by IL-2 released in vivo and could be a potent pharmacologic agent.

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After total laryngectomy, the cricopharyngeus muscle, when intact, appears to inhibit the free flow of saliva and secretions past the pharyngeal repair into the upper esophagus. The authors hypothesize that cricopharyngeus myotomy reduces sphincteric pressure, thereby diminishing forces against the pharyngeal suture line. Peak pharyngeal pressures were recorded in patients who underwent total laryngectomy with and without cricopharyngeus myotomy. In patients without concurrent myotomy, peak pharyngeal pressures were all greater than 60 mm Hg. With concurrent myotomy, peak pharyngeal pressures averaged less than 40 mm Hg. Concurrent myotomy carries with it the potential for minimizing postoperative fistulization, eliminating dysphagia of cricopharyngeus spasm, and improving the acquisition of alaryngeal speech.

A new approach to microlaryngeal surgery using a specially designed video microlaryngoscope with a rigid endoscopic telescope and an attached video camera was introduced by Kantor et al in 1990. The ability to video document and perform surgery of the larynx by viewing a high-resolution television image was demonstrated. This method was recommended over the standard microscopic technique for increased visibility with greater depth of field, unimpeded instrument access, instant documentation, and superior teaching value. The authors tried this new method and the standard microscopic technique at the same sitting on a series of patients. This paper will compare these two different techniques and discuss their advantages and disadvantages. Although the new method has many advantages, the standard microscopic technique remains as a valuable method in laryngeal surgery.

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