Anatomical implication of less occurrence of inferior oblique muscle entrapment in orbital floor trapdoor fracture

Diagnostic pitfalls in pediatric orbital entrapment fractures

Prompt diagnosis and management of orbital entrapment fractures in the pediatric patient have been advocated. This retrospective study analyzed a cohort of orbital entrapment fractures in pediatric patients with regard to diagnostic pitfalls, treatment and outcomes in a Level I trauma center in Germany. Based on medical records and radiological imaging, patients under the age of 18 years who presented with orbital fractures during 2009-2021 were analyzed. Overall, 125 patients presented with orbital fractures, of whom 29 patients (23.2%) had orbital entrapment fractures. The majority of patients presented with monocle hematoma (n = 23), diplopia (n = 20), and/or restricted extraocular eye movement (n = 14). While all patients with orbital entrapment fractures underwent three-dimensional imaging, 10 radiological reports (34.5%) did not include findings on orbital entrapment fractures. All patients underwent surgical exploration in less than 24 h. In 12 patients, clinical symptoms such as diplopia and restricted ocular elevation were documented upon postoperative evaluation before discharge. Considering the significant proportion of orbital entrapment fractures that are not noted on radiological imaging, prompt clinical examination should be initiated in pediatric patients at risk for orbital fractures. Urgent surgical intervention should be recommended in entrapment fractures.

Orbital Trapdoor Fracture With Extraocular Muscle Entrapment in Adults: A Case Series

PURPOSE

To report adult patients with an orbital trapdoor fracture with extraocular muscle entrapment.

METHODS

We retrospectively reviewed 566 adult patients (>18 years) with a pure orbital fracture who were referred to us from January 2016 to May 2023. The following data were collected: age, sex, affected side, causes of injury, concomitant ocular injury and nasal bone fracture, presence or absence of oculocardiac reflex and infraorbital nerve hypesthesia, period from injury to surgery, follow-up period, and pre- and postoperative limitation of extraocular muscle motility and fields of a binocular single vision.

RESULTS

We found 5 patients (0.9%) with an orbital trapdoor fracture with extraocular muscle entrapment (age range, 19-47 years; all males; 2 right and 3 left). Causes of injury included performing a bench press, fall, assault, boxing, and bicycle accident. Entrapment of the inferior and medial recti muscles was seen in 2 and 3 patients, respectively. None of the patients had any sign of oculocardiac reflex. After surgical reduction, the field of binocular single vision became normal in 3 patients and was incompletely recovered in 2 patients, in whom consultation with us was delayed.

CONCLUSION

Adults with extraocular muscle entrapment may not present with an oculocardiac reflex. Urgent release of an entrapped muscle is, however, still recommended to avoid permanent limitation of extraocular muscle motility.

The relationship between orbital floor fracture patterns around the infraorbital groove and development of infraorbital nerve hypoesthesia: a computed tomographic study

PURPOSE

To examine the relationship between patterns of orbital floor fracture around the infraorbital groove and development of infraorbital nerve hypoesthesia.

METHODS

This retrospective, observational study included 200 patients (200 sides) of pure orbital floor fracture with or without medial orbital wall fracture. Data on the presence or absence of infraorbital nerve hypoesthesia were collected from medical records. Based on coronal computed tomographic images, patients were classified into 3 groups: a fracture extending medially to (medial group), into (in-groove group), and laterally to the infraorbital groove (lateral group).

RESULTS

Infraorbital nerve hypoesthesia was found in 72 patients (36.0%). A fracture extended into or laterally to the infraorbital groove in 86.2% of patients with infraorbital nerve hypoesthesia, while a fracture was limited to the portion medial to the infraorbital groove in 77.3% of patients without infraorbital nerve hypoesthesia (P < 0.001). A logistic regression analysis demonstrated that patients in the lateral and in-groove groups were highly associated with development of infraorbital nerve hypoesthesia, with an odds ratio of 134.788 in the lateral group (95% confidence interval, 30.496-595.735; P < 0.001) and that of 20.323 in the in-groove group (95% confidence interval, 6.942-59.499; P < 0.001) with the medial group as the reference.

CONCLUSIONS

This study indicates that patients with orbital floor fracture extending into or laterally to the infraorbital groove have a high risk of infraorbital nerve hypoesthesia, compared to those with orbital floor fracture limited to the portion medial to the infraorbital groove.

Comparison of the decompressive effect of different surgical procedures for dysthyroid optic neuropathy using 3D printed models

PURPOSE

To compare the decompressive effect around the optic nerve canal among 3 different decompression procedures (medial, balanced, and inferomedial) using 3D printed models.

METHODS

In this experimental study, based on data obtained from 9 patients (18 sides) with dysthyroid optic neuropathy, a preoperative control model and 3 plaster decompression models were created using a 3D printer (total, 72 sides of 36 models). A pressure sensor was placed at the optic foramen, and the orbital space was filled with silicone. The surface of the silicone was pushed down directly, and changes in pressure were recorded at 2-mm increments of pushing.

RESULTS

At 10 mm of pushing, there was significantly lower pressure in the medial (19,782.2 ± 4319.9 Pa, P = 0.001), balanced (19,448.3 ± 3767.4 Pa, P = 0.003), and inferomedial (15,855.8 ± 4000.7 Pa, P < 0.001) decompression models than in the control model (25,217.8 ± 6087.5 Pa). Overall, the statistical results for each 2-mm push were similar among the models up to 10 mm of pushing (P < 0.050). At each push, inferomedial decompression caused the greatest reduction in pressure (P < 0.050), whereas there was no significant difference in pressure between the medial and balanced decompression models (P > 0.050).

CONCLUSION

All 3 commonly performed decompression procedures significantly reduced retrobulbar pressure. Because inferomedial decompression models obtained the greatest reduction in pressure on the optic nerve canal, inferomedial decompression should be considered the most reliable procedure for rescuing vision in dysthyroid optic neuropathy.