Department of Ophthalmology, The Permanente Medical Group, Kaiser Permanente, Redwood City, California, USA.
Ophthalmology. 2011 Nov;118(11):2286-95. doi: 10.1016/j.ophtha.2011.04.031. Epub 2011 Jul 23.
To explain the mechanism for acquired enophthalmos after ventriculoperitoneal shunting (VPS).
Case series and a case-control study.
Four study patients with bilateral enophthalmos after VPS and 10 control subjects.
Case description of 4 study patients. Calculated orbital volumes for 2 study patients were compared with controls using the Wilcoxon rank-sum test.
Exophthalmometry measurements and total orbital and fat volumes.
Patient 1 is a 25-year-old man who presented with progressive enophthalmos 3 years after VPS for traumatic intracranial bleeding. Imaging demonstrated upward expansion of the orbital roof and evidence of intracranial hypotension. The intracranial pressure (ICP) was 20 mm H₂O. The enophthalmos improved after shunt revision. Patient 2 is a 19-year-old man who presented with progressive enophthalmos 18 months after VPS for traumatic intracranial hemorrhage. Patient 3 is a 38-year-old woman who presented with bilateral enophthalmos 15 years after VPS after a ruptured aneurysm. Imaging showed orbital expansion. Patient 4 is a 16-year-old man who presented with severe enophthalmos 5 years after a VPS for aneurysm-related hemorrhage. Imaging demonstrated orbital enlargement and findings of intracranial hypotension. Intracranial pressure ranged between -200 and 0 mm H₂O. Shunt revision improved the enophthalmos. Total orbital volumes were significantly greater in the study patients than in the controls. Control subjects (5 male, 5 female, ages 23-45 years) had an average right orbital volume of 24.6 ± 3.3 cm³ (n = 10). In comparison, the right orbital volumes of patients 1 and 3 were 32.6 and 32.1 cm³. Similar results were found for the left orbits (23.9 ± 2.7 cm³ [control average] vs. 35.9 and 32.6 cm³). In patient 1, the post-shunt volumes increased 14% (right) and 23% (left) from pre-shunt volumes. In contrast, orbital fat volume was not statistically significantly different between the control group and enophthalmic patients (right orbit control mean 7.94 ± 3.1 cm³ [n = 10] vs. 7.9 and 9.8 cm³; left orbit control mean 7.88+3.1 cm³ vs. 9.2 and 10.0 cm³).
Enophthalmos after VPS results primarily from chronic intracranial hypotension. Low ICP causes expansion of orbital volume with no fat atrophy. In such patients, shunt revision with a pressure-regulating valve to correct intracranial hypotension should be considered.
FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.
解释脑室腹腔分流（VPS）后获得性眼球内陷的机制。
病例系列和病例对照研究。
4 例 VPS 后双侧眼球内陷的患者和 10 例对照。
对 4 例患者进行病例描述。使用 Wilcoxon 秩和检验比较 2 例研究患者的计算眶容积与对照组。
眼球突出度测量值和总眶容积及脂肪容积。
患者 1 是一名 25 岁男性，VPS 治疗创伤性颅内出血 3 年后出现进行性眼球内陷。影像学显示眶顶向上扩张，并存在颅内低血压证据。颅内压（ICP）为 20mmHg。分流管更换后，眼球内陷改善。患者 2 是一名 19 岁男性，VPS 治疗创伤性颅内出血 18 个月后出现进行性眼球内陷。患者 3 是一名 38 岁女性，VPS 治疗破裂动脉瘤 15 年后出现双侧眼球内陷。影像学显示眶扩张。患者 4 是一名 16 岁男性，VPS 治疗与动脉瘤相关出血 5 年后出现严重眼球内陷。影像学显示眶扩大和颅内低血压表现。颅内压在-200 至 0mmHg 之间。分流管更换改善了眼球内陷。研究患者的总眶容积明显大于对照组。对照组（5 男，5 女，年龄 23-45 岁）右侧眶容积平均为 24.6±3.3cm³（n=10）。相比之下，患者 1 和 3 的右侧眶容积分别为 32.6 和 32.1cm³。左侧眶容积也有类似结果（对照组平均 23.9±2.7cm³[平均]，分别为 35.9 和 32.6cm³）。患者 1 的分流管更换后，右侧眶容积增加了 14%，左侧眶容积增加了 23%。相比之下，对照组和眼球内陷患者的眶脂肪容积无统计学差异（右侧眶对照组平均 7.94±3.1cm³[n=10]，分别为 7.9 和 9.8cm³；左侧眶对照组平均 7.88+3.1cm³，分别为 9.2 和 10.0cm³）。
VPS 后眼球内陷主要由慢性颅内低血压引起。低 ICP 导致眶容积扩张，无脂肪萎缩。在这种情况下，应考虑通过更换带有压力调节阀的分流管来纠正颅内低血压。
作者没有与本文讨论的任何材料有关的专有或商业利益。
