Scholarlink

Purpose <p>to measure vitreous fragments generated at 5,000 and 20,000 cuts-per-minute (CPM) by means of Scanning Electronic Microscopy (SEM; fragments &gt; 550&#xa0;nm), Optical Profilometry and Dynamic Light Scattering (DLS; fragments 10–550&#xa0;nm) and assess if cur-rate affects vitreous fragment size.</p> Methods <p>Vitreous samples at 5k and 20&#xa0;K CPM were collected from 3 patients undergoing 25G pars plana vitrectomy for macular pucker. SEM and Profilometry measured fragment size in 6 drops from each sample, DLS analysed the remainder. Each patient contributed 2 samples at 5&#xa0;K and 20&#xa0;K CPM taken at the beginning of surgery.</p> Results <p>The median volume was 1,153.6 µm3 (IQR 2,322.3 µm3) at 5k and 72,4 µm3 (IQR 923.4 µm3) at 20k, respectively (Mann-Whitney <i>p</i> = 0.074); the variability of vitreous fragment volume was higher for 5&#xa0;K CPM group (<i>p</i> = 0.036). DSL median fragment dimension in the 10–550&#xa0;nm range was 50.7&#xa0;nm (IQR 87.8&#xa0;nm) for the 5&#xa0;K CPM group and 43.8&#xa0;nm (IQR 95.9&#xa0;nm) for the 20&#xa0;K CPM group (<i>p</i> &lt; 0.001).</p> Conclusion <p>A fourfold increase in cut-rate did not produce significantly smaller vitreous fragments but the 20&#xa0;K CPM samples showed less variability. Fragments size spanned 5 orders of magnitude (from nanometers to hundreds of microns), challenging the assumption that blade action produces uniform fragments. Fragment size variability minimally affected by cut-rate, questions the blade action as the main or only factor shearing vitreous. Elongation stress and shear stress most likely play a prominent role.</p> Graphical abstract <p></p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Vitreous collagen fragment dimensions after vitrectomy: a pilot study addressing the cut-rate enigma

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2026年4月2日

查看全文
  • Tommaso Rossi,
  • Alessio Bocedi,
  • Sara Notari,
  • Diego Sbardella,
  • Laura Fazi,
  • Anna Priorello,
  • Giorgio Querzoli,
  • Sara Giammaria,
  • Gianmario Anselmi,
  • Mario R. Romano,
  • Mattia Gianandrea Gaboardi,
  • Giovanni Romanelli,
  • Roberto Senesi,
  • David H. Steel,
  • Triestino Minniti

摘要

Purpose

to measure vitreous fragments generated at 5,000 and 20,000 cuts-per-minute (CPM) by means of Scanning Electronic Microscopy (SEM; fragments > 550 nm), Optical Profilometry and Dynamic Light Scattering (DLS; fragments 10–550 nm) and assess if cur-rate affects vitreous fragment size.

Methods

Vitreous samples at 5k and 20 K CPM were collected from 3 patients undergoing 25G pars plana vitrectomy for macular pucker. SEM and Profilometry measured fragment size in 6 drops from each sample, DLS analysed the remainder. Each patient contributed 2 samples at 5 K and 20 K CPM taken at the beginning of surgery.

Results

The median volume was 1,153.6 µm3 (IQR 2,322.3 µm3) at 5k and 72,4 µm3 (IQR 923.4 µm3) at 20k, respectively (Mann-Whitney p = 0.074); the variability of vitreous fragment volume was higher for 5 K CPM group (p = 0.036). DSL median fragment dimension in the 10–550 nm range was 50.7 nm (IQR 87.8 nm) for the 5 K CPM group and 43.8 nm (IQR 95.9 nm) for the 20 K CPM group (p < 0.001).

Conclusion

A fourfold increase in cut-rate did not produce significantly smaller vitreous fragments but the 20 K CPM samples showed less variability. Fragments size spanned 5 orders of magnitude (from nanometers to hundreds of microns), challenging the assumption that blade action produces uniform fragments. Fragment size variability minimally affected by cut-rate, questions the blade action as the main or only factor shearing vitreous. Elongation stress and shear stress most likely play a prominent role.

Graphical abstract