Berthout A, Vignal C, Jacomet P V, Galatoire O, Morax S
Service d'ophtalmologie et de chirurgie orbitopalpébrolacrymale, fondation ophtalmologique Rothschild, 25-29, rue Manin, 75019 Paris, France.
J Fr Ophtalmol. 2010 Nov;33(9):623-9. doi: 10.1016/j.jfo.2010.08.004. Epub 2010 Nov 2.
In Graves' orbitopathy, the volumetric increase of the oculomotor muscles and orbital fat leads to exophthalmia and a rise in orbital pressure. This rise in pressure may be implicated in the appearance of a compressive optic neuropathy. To investigate this increase in pressure and its variations accompanying surgical decompression, systematic measurements were taken before, during, and after every case of orbital decompression in Graves' disease.
The intraorbital pressure before the surgical procedure was 14.05 mmHg ± 9.19 for a normal value estimated in the literature at 4 mmHg ± 1.5 (statistically significant difference, P<0.0001). In the group presenting a compressive optic neuropathy (NO), the preoperative pressure was 26.8 mmHg ± 7.85 versus 9.8 mmHg ± 4.2 in the group without NO: the pressure was significantly higher in the group with NO (P<0.001). After orbital decompression (one to three walls depending on the severity of the exophthalmia), the pressure was measured at 4.3 mmHg ± 2.53 for the entire series: 6.4 mmHg ± 2.07 in the group with NO versus 3.6 mmHg ± 2.32 in the group without NO (significant difference, P<0.05). The total decrease in pressure induced by the surgery was 9.75 mmHg ± 7.55 and was significantly greater for the group with NO: reduction of 20.4 mmHg versus 6.2 mmHg for the group without NO (P<0.001). The reduction in pressure was greater after collapse of the first wall (floor) than after collapse of following walls for all groups (P<0.001). The maximum pressure observed during the intervention (caused by the instruments) was measured at 78.3 mmHg ± 23.47 without pupillary changes.
This study shows that the intraorbital pressure is increased in Graves' orbitopathy and more in serious forms with compressive optic neuropathy. Orbital decompression, as its name indicates, provides decompression and a return to a near-normal orbital pressure situation. Compressive optic neuropathy does not result only from the direct compression of the oculomotor muscles on the optic nerve, but also from an overall rise in the pressure level within the orbital cavity.
Intraorbital pressure is increased in Graves' orbitopathy, participating in the appearance of compressive optic neuropathy. Orbital decompression provides a significant reduction in intraorbital pressure.
在格雷夫斯眼眶病中，动眼肌和眶脂肪的体积增加导致眼球突出和眶压升高。这种压力升高可能与压迫性视神经病变的出现有关。为了研究这种压力升高及其伴随手术减压的变化，对每例格雷夫斯病眼眶减压病例在手术前、手术中和手术后进行了系统测量。
手术前眶内压力为14.05 mmHg±9.19，而文献估计的正常值为4 mmHg±1.5（统计学上有显著差异，P<0.0001）。在出现压迫性视神经病变（NO）的组中，术前压力为26.8 mmHg±7.85，而在无NO的组中为9.8 mmHg±4.2：有NO的组压力明显更高（P<0.001）。眼眶减压后（根据眼球突出的严重程度切除一至三壁），整个系列的压力测量值为4.3 mmHg±2.53：有NO的组为6.4 mmHg±2.07，无NO的组为3.6 mmHg±2.32（有显著差异，P<0.05）。手术引起的压力总下降为9.75 mmHg±7.55，有NO的组下降更显著：下降20.4 mmHg，无NO的组下降6.2 mmHg（P<0.001）。所有组在第一壁（眶底）塌陷后压力下降比后续壁塌陷后更大（P<0.001）。干预期间观察到的最大压力（由器械引起）在无瞳孔变化的情况下测量为78.3 mmHg±23.47。
本研究表明，格雷夫斯眼眶病中眶内压力升高，在伴有压迫性视神经病变的更严重形式中升高更明显。眼眶减压，顾名思义，可提供减压并使眶压恢复到接近正常的状态。压迫性视神经病变不仅是由于动眼肌对视神经的直接压迫，还源于眶腔内压力水平的整体升高。
格雷夫斯眼眶病中眶内压力升高，参与了压迫性视神经病变的出现。眼眶减压可使眶内压力显著降低。
