The Use of 3D Printing in Orbital Fractures

Does the Use of a Customized Titanium Reconstruction Plate for Orbital Fractures Result in Better Orbital Volume and Outcome

Enrollment and study activities were initially suspended due to COVID-19 and it has been determined that the study will not resume.

The study is a prospective randomized longitudinal clinical study to compare pre-adapted patient-specific orbital implants utilizing an office-based 3-D printer versus standard non-adapted orbital implants (the latter being the traditional approach and current standard of care).

Orbital fracture, which accounts for 10-25% of facial fractures, is one of the most difficult facial fractures to treat. The complex bone anatomy and the proximity of adjacent vital structures make reconstruction of these fractures challenging. Inadequate orbital fracture reconstruction leads to cosmetic and functional complications. Cosmetic complications include enophthalmos, which is defined as posterior displacement of the eyeball within the orbit due to changes in the volume of the orbit (bone) relative to its contents (the eyeball and orbital fat). Functional complications include diplopia, defined as a type of vision disorder in which two images are seen of a single object. This is a prospective randomized clinical study with longitudinal follow-up. The study duration is 2 years, and it will be conducted at Grady Memorial Hospital (GMH). The study targets low-income, urban adults suffering blunt facial trauma who are diagnosed with unilateral orbital fracture. The purpose of this study is to compare pre-adapted patient-specific orbital implants utilizing an office-based 3-D printer versus standard non-adapted orbital implants. Main aims of the study are to 1) preoperatively generate a patient-specific model to pre-adapt the titanium mesh for use in unilateral orbital fractures; 2) accurately restore the orbital volume to pre-injury levels; 3) prevent postoperative complications including enophthalmos and diplopia; and 4) decrease the operative time, therefore decreasing overall cost and increasing value.

Patients undergo orbital reconstruction using pre-adjusted patient-specific orbital implants with office-based 3-dimensional printers (OB3DP)

Patients undergo orbital reconstruction with non-patient-specific orbital implants (traditional approach, Control Group) which is a standard stock orbital plate

In this treatment group subjects, using office-based 3-dimensional printers (OB3DP) a patient-specific pre-adjusted (pre-bend) orbital plates will be made using over-the-counter titanium plates that are manually adjusted according to the printed model. The plates are then send to sterilization for preparation.

In this control group subjects will receive non-patient-specific orbital implants which is standard stock orbital plate that is adapted intraoperatively to the fractured orbit

Orbital Volume of the Injured Orbit Compared to the Contralateral Uninjured Orbit as Assessed by CT Scan Between the Treatment and Control Groups

The Primary Investigator will evaluate the orbital volume using OsiriX (medical software). Orbital volume measurements will be obtained to compare the injured and uninjured (contralateral) orbital volumes. OsiriX MD offers advanced processing techniques and has the ability to precisely measure orbital volume. It also utilizes the DICOM data from the immediate postoperative CT scans.

Number of Subjects With Reduction of Orbital Volume to Less Than 2 cm3 Between the Treatment and Control Groups

Adequate orbital volume reduction, defined as a reduction of orbital volume to less than 2 cm3. The Primary Investigator will evaluate the orbital volume using OsiriX (medical software). Number of subjects with reduction of orbital volume to less than 2 cm3 between the treatment and control groups are recorded

Number of Subjects With a Difference of More Than 2 mm Between the Two Orbits Between the Treatment and Control Groups

A difference of more than 2 mm between the two orbits is diagnostic for enophthalmos. Enophthalmos is assessed by clinical examination using a Hertel exophthalmometer. The measurement is taken from the lateral orbital rim to the corneal apex. The normal range is 12-21 mm. Upper normal limit for people of African origin is a little higher, about 23-24 mm. A difference greater than 2 mm between the eyes is significant.

Infection is defined by the presence of postoperative pus in the wound, a sinus tract or fistula, or elevated white blood cell count (WBC) >11.0x109/L combined with erythematous skin and swelling on the operated side more than on the un-operated side. WBC is measured with a blood draw test. Infection will be confirmed with clinical examination along with blood tests.

Infraorbital nerve injury is assessed by clinical examination using neurosensory testing (NST). NST is a standardized methodology designed to objectively evaluate sensory nerve function. The sensory impairment is determined by 3 levels of testing; each level classifies a specific type of sensory nerve injury.

Number of Subjects With Intraocular Pressure (IOP) > 40 mmHg Between the Treatment and Control Groups

Intraocular pressure (IOP) > 40 mmHg is diagnostic of orbital compartment syndrome. Orbital compartment syndrome is assessed through clinical examination using tonometry test. Tonometry is a diagnostic test that measures the pressure inside your eye, which is called intraocular pressure (IOP). The normal pressure range is 12 to 22 mm Hg.

Operating time will be calculated from fracture exposure and identification to the final implant placement and fixation and will be recorded in minutes. This will be compared between the two treatment groups. To record and compare the operative time between the two groups, a stopwatch will be utilized.

Isolated orbital floor fracture patients do not require a pre-operative hospital stay. Length of stay will be calculated in terms of postoperative hospital stay (days). Length of stay in cases of complex orbital fracture will be calculated in terms of pre-operative and postoperative hospital stay (days). The number of days subject stays in the hospital are measured and compared

Treatment charges will be calculated with consideration of the following: Facility operating room charges, which include anesthesia time (surgical time multiplied by the facility rate of $33/ minute). Hardware charges (plates and screws). Length Of Stay charges (LOS multiplied by the facility daily rate of $1,690/ day). The cost of the 3D printed model including the cost of the 3D printer and filaments ($1.5). All treatment charge variables will be provided by the Grady Memorial Hospital Financial Planning and Analysis center. Total treatment charges facility operating room charges, hardware charges, LOS, and the 3D printed model cost will be compared between groups in a manner similar to that outlined in previous studies by our group.

Number of Subjects That Develop Restricted Extraocular Motility That Was Not Present Before Between the Treatment and Control Groups

Extra-ocular motility is assessed through clinical examination. The patient should be able to move the eyes through the six cardinal positions of gaze (left, right, up and right, up and left, down and right, down and left). All patients will be examined for the following: Development of restricted extraocular motility that was not present prior to the surgery. Persistent restriction of extraocular motility after the surgery

Number of Subjects With Inability to Achieve the Normal Orbital Contour Between the Treatment and Control Groups

Inability to achieve the normal orbital contour as assessed in the immediate post-operative Computerized Tomography (CT) scan. Maxillofacial non-contrast CT scans according to the protocol will be obtained as part of the standard of care in managing orbital fractures and will be obtained for all subjects post operatively.

Inclusion Criteria: Agreed to be enrolled in the study. Indications for surgical repair of orbital floor and/ wall fractures are dependent on several factors: Correction or prevention of cosmetic deformity ( enophthalmos or inferior dystopia; disruption of greater than 50% of the orbital floor is likely to cause cosmetically apparent enophthalmos. Correction of unresolved diplopia (7 to 11 days) in the sitting of soft tissue prolapse with a positive forced duction test. Immediate correction of diplopia in the sitting inferior rectus muscle incarceration and a positive forced duction test. Immediate correction in a symptomatic patient with orbital floor ( trapdoor) fracture that has elicited the oculocardiac reflex. At least 18 years of age. Unilateral orbital floor fracture. No history of orbital trauma. Healthy contralateral orbit. Underwent orbital reconstruction. Admitted to GMH. Returned for the 6-week follow-up. Exclusion Criteria: Refuse study enrollment. Are younger than 18 years. Pregnant women. Prisoner Unable to obtain consent (cognitively impaired) Are admitted to hospitals other than Grady Memorial Hospital.