Blandford Alexander D, Cherfan Daniel G, Drake Richard L, McBride Jennifer M, Hwang Catherine J, Perry Julian D, Cheng Olivia T
Cole Eye Institute, Cleveland Clinic Foundation.
Department of Surgery, Cleveland Clinic Lerner College of Medicine.
Ophthalmic Plast Reconstr Surg. 2018 Sep/Oct;34(5):440-442. doi: 10.1097/IOP.0000000000001042.
To elucidate the mechanisms underlying nasolacrimal air regurgitation (AR) in the setting of continuous positive airway pressure therapy.
Twelve nasolacrimal systems of 6 fresh female human cadavers were evaluated individually for AR using continuous positive airway pressure therapy before any nasolacrimal procedure. Cadavers were then randomly assigned to undergo nasolacrimal duct probing or endoscopic dacryocystorhinostomy and then each hemisystem was again evaluated for AR. The pressure where AR was first observed (discovery pressure) or maximum possible pressure in systems without AR was recorded. In systems that demonstrated AR, the pressure was then gradually decreased to the lowest pressure where regurgitation persisted. This pressure was recorded as the secondary threshold pressure.
None of the 12 unoperated nasolacrimal systems or the 6 systems that underwent nasolacrimal duct probing demonstrated AR through the maximum continuous positive airway pressure therapy (30 cm H2O). After endoscopic dacryocystorhinostomy, all 6 nasolacrimal systems demonstrated AR. The mean discovery pressure was 16.0 cm H2O (range, 14.0-18.0 cm H2O) and mean secondary threshold pressure was 7.25 cm H2O (range, 6.5-8.0 cm H2O).
Air regurgitation during continuous positive airway pressure therapy in the setting of prior endoscopic dacryocystorhinostomy can be replicated in a cadaver model. The secondary threshold pressures required for AR in this model were similar to AR pressures reported clinically. Prior to dacryocystorhinostomy, patients using continuous positive airway pressure therapy should be counseled on AR, and physicians should consider this phenomenon when evaluating ophthalmic complaints in postoperative patients on positive airway pressure therapy.
阐明在持续气道正压通气治疗背景下鼻泪管空气反流（AR）的潜在机制。
在进行任何鼻泪管手术之前，使用持续气道正压通气治疗对6具新鲜女性人体尸体的12个鼻泪系统分别进行AR评估。然后将尸体随机分为接受鼻泪管探查或内镜下泪囊鼻腔造口术，之后再次对每个半系统进行AR评估。记录首次观察到AR时的压力（发现压力）或未出现AR的系统中的最大可能压力。在出现AR的系统中，然后将压力逐渐降低至反流持续存在的最低压力。该压力记录为次要阈值压力。
12个未手术的鼻泪系统或6个接受鼻泪管探查的系统中，通过最大持续气道正压通气治疗（30 cm H₂O）均未出现AR。内镜下泪囊鼻腔造口术后，所有6个鼻泪系统均出现AR。平均发现压力为16.0 cm H₂O（范围14.0 - 18.0 cm H₂O），平均次要阈值压力为7.25 cm H₂O（范围6.5 - 8.0 cm H₂O）。
在先前内镜下泪囊鼻腔造口术的背景下，持续气道正压通气治疗期间的空气反流可在尸体模型中重现。该模型中AR所需的次要阈值压力与临床报道的AR压力相似。在进行泪囊鼻腔造口术之前，应对使用持续气道正压通气治疗的患者进行AR方面的咨询，并且医生在评估接受正压通气治疗的术后患者的眼科症状时应考虑到这种现象。
