The effect of optical design on micromanipulator spot size using CO2 laser irradiation

Objective: The study goal was to compare the laser spot size created using reflective and refractive micromanipulators with a CO₂ laser and to determine the sensitivity of spot size to laser power. Study Design and Setting: A CO₂ laser and operating microscope (400-mm focal length) was coupled to either a reflective (Cassegrain-like) or refractive micromanipulator. Laser spot size was determined by measuring the region of ablation created by laser irradiation of wood (dry tongue depressors), exposed photographic film, and agar gel using optical micrometry. Laser power varied from 0.5 to 20 W with pulse durations of 0.1 and 0.5 second. Results: The reflective micromanipulator demonstrated overall smaller spot sizes for a given laser power and lower incremental change in spot size with increasing power. The reflective design demonstrated less sensitivity to increases in laser power. Conclusions: Micromanipulator optical design can result in significant differences in laser spot size. The reflective device used in this study demonstrated less sensitivity to increasing laser power. (Otolaryngol Head Neck Surg 2002;126:593-597.)     

High-Risk Cutaneous Squamous Cell Carcinoma without Palpable Lymphadenopathy: Is There a Therapeutic Role for Elective Neck Dissection?

PURPOSE: The beneficial role of elective neck dissection (END) in the management of high-risk cutaneous squamous cell carcinoma (CSCC) of the head and neck remains unproven. Some surgical specialists suggest that END may be beneficial for patients with clinically node-negative (N0) high-risk CSCC, but there are few data to support this claim. We reviewed the available literature regarding the use of END in the management of both CSCC and head and neck SCC (HNSCC). METHODOLOGY: The available medical literature pertaining to END in both CSCC and HNSCC was reviewed using PubMed and Ovid Medline searches. RESULTS: Many surgical specialists recommend that END be routinely performed in patients with N0 HNSCC when the risk of occult metastases is estimated to exceed 20%; however, patients who undergo END have no proven survival benefit over those who are initially staged as N0 and undergo therapeutic neck dissection (TND) after the development of apparent regional disease. There is a lack of data regarding the proper management of regional nodal basins in patients with N0 CSCC. In the absence of evidence-based data, the cutaneous surgeon must rely on clinical judgment to guide the management of patients with N0 high-risk CSCC of the head and neck. CONCLUSIONS: Appropriate work-up for occult nodal disease may occasionally be warranted in patients with high-risk CSCC. END may play a role in only a very limited number of patients with high-risk CSCC.