Sixteen patients (11 males and 5 females; average age, 25 years; range, 15–51 years) met the inclusion criteria. Six of the fractures were on the right side, and 10 were on the left. The average time interval between injury and surgery was 17.4 ± 10.0 days (range, 4–45 days). The average follow-up period was 9 months (range, 6–17 months). After surgery, nine (56%) patients had enophthalmos greater than 2 mm. Enophthalmos resolved in 15 (94%) patients after surgery, and 2 mm of enophthalmos remained in one patient. The decrease in enophthalmos after surgery was 1.19 ± 1.05 mm. The improvement of enophthalmos after surgery was statistically significant (P < 0.01), as expected.
The orbital volume was measured before surgery. The mean orbital volume of the unaffected orbits was 23.94 ± 3.47 cm
3, and the mean volume of the affected orbits was 28.16 ± 4.32 cm
3. After surgery, the orbital volume on the surgical side was decreased to 24.08 ± 3.22 cm
3; thus, an average decrease was achieved of 4.08 ± 2.45 cm
3. The volume and enophthalmos of the unaffected and affected orbits, and the differences between the preoperative and postoperative volumetric differences of the two sides are listed in
Table 1 . There was a statistically significant difference in orbital volume between the two sides before operation (
t = 3.046,
P = 0.005), whereas there was no significant difference after reconstruction (
t = 0.069,
P = 0.945;
Table 2 ). The increased preoperative orbital volume and the extent of enophthalmos correlated significantly (
r = 0.658,
P = 0.003). The orbital volume change after reconstructive surgery and the resolved enophthalmos also correlated significantly (
r = 0.715,
P = 0.001), with the regression formula:
E = 0.72
V − 0.06
(Fig. 3) . The expected volume decrease of the fractured orbit associated with 2 mm of enophthalmos correction by surgery was 2.86 cm
3, as estimated from linear regression.
Diplopia was resolved in five of six patients within 6 months after surgery. Only one patient had hypertropia, which resolved 1 month after the operation. According to subjective assessment, the position of channel implants in the anterior and middle portion was considered ideal in all cases, except one, in which the CT scan showed poor positioning of the implant in the posterior portion
(Fig. 4) .