Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Canada.
Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Canada.
Ophthalmol Retina. 2020 Sep;4(9):911-918. doi: 10.1016/j.oret.2020.03.029. Epub 2020 Apr 10.
To demonstrate the relationship between an intraocular gas bubble, the retina, and the residual intraocular fluid in different head positions using orbital magnetic resonance imaging (MRI) in 3 patients who underwent pars plana vitrectomy (PPV) with gas tamponade.
Novel study.
Patients undergoing PPV with gas-fluid exchange (sulfurhexafluoride [SF] or perfluoropropane [CF]).
Magnetic resonance imaging scans were obtained in 3 patients undergoing PPV with gas-fluid exchange (SF or CF). All surgeries were performed by a single surgeon (E.D.M.). On the first postoperative day, the volume of intraocular gas fill was estimated separately by 2 surgeons (A.H. and E.D.M). Four orbital MRI scans were obtained from different head positions, including face up (supine), face down (prone on a massage pillow), flat on the right side, and flat on the left side.
Relationship between the gas bubble and residual vitreous fluid.
The MRI images demonstrated, with excellent contrast, the gas and fluid locations in the vitreous cavity in all scans. The relationship between the gas bubble and residual vitreous fluid showed a rapid shift when the patient's head position changed. The MRI images demonstrated that with both 70% gas fill and 95% gas fill, lying on the side can give better support to the inferior retina than face-down positioning. The images demonstrated the importance of accurate head positioning, because a slight change in head position resulted in inadequate contact between the anterior inferior retina and the gas bubble.
To our knowledge, this is the first time that the relationship between an intraocular gas bubble and contact with the retina has been evaluated in different head positions in vivo using MRI imaging. The MRI images demonstrated that side positioning gives better contact between the gas bubble and the inferior and anterior retina than prone positioning even when the gas fill is only 70% of the vitreous cavity.
通过对 3 例接受经睫状体平坦部玻璃体切除术（PPV）联合气体填充的患者进行眼眶磁共振成像（MRI），展示不同头位时眼内气泡、视网膜和残余眼内液之间的关系。
新型研究。
接受 PPV 联合气体-液交换（SF 或 CF）的患者。
对 3 例接受 PPV 联合气体-液交换（SF 或 CF）的患者进行 MRI 扫描。所有手术均由一位外科医生（E.D.M.）完成。术后第一天，由两位外科医生（A.H. 和 E.D.M.）分别估计眼内气体填充量。从不同的头位共获得 4 个眼眶 MRI 扫描，包括面朝上（仰卧位）、面朝下（俯卧在按摩枕上）、右侧卧位和平卧位。
气泡与残余玻璃体的关系。
MRI 图像以极好的对比度显示了所有扫描中玻璃体腔内的气体和液体位置。当患者头位改变时，气泡与残余玻璃体的关系迅速改变。MRI 图像显示，在 70%气体填充和 95%气体填充时，侧卧位比俯卧位更能为下视网膜提供更好的支撑。这些图像表明准确的头部定位非常重要，因为头部位置的轻微改变会导致前下方视网膜与气泡接触不充分。
据我们所知，这是首次使用 MRI 成像评估不同头位时眼内气泡与视网膜接触的关系。MRI 图像显示，即使气体填充仅占玻璃体腔的 70%，侧卧位也比俯卧位更能使气泡与下视网膜和前视网膜更好地接触。
