In patients with blunt orbital trauma without immediate indications for canthotomy, can CT findings predict subsequent orbital compartment syndrome or vision loss?
Date First Published:
November 29, 2025
Last Updated:
November 29, 2025
Report by:
Dr Arvils Nesko (1), Rosie Wadsworth (2), Dr Jake Gluyas-Harris (3), Dr Blair Graham (4), Dr Tim Nutbeam (5), (1) EM ST3; (2) Medical Student; (3) EM ST4; (4) Clinical Radiology ST3; (5) EM Consultant ((1, 4, 5) UHP NHS Trust; (2) University of Plymouth; (3) Royal Devon University Healthcare NHS Foundation Trust)
Search checked by:
Rosie Wadsworth, Medical student, University of Plymouth
Three-Part Question:
In [patients with orbital trauma who don’t require immediate canthotomy] [are there CT findings] [that are associated with subsequent canthotomy or vision loss]?
Clinical Scenario:
An adult male is involved in a high-speed frontal MVC, sustaining significant facial injuries. You are part of the trauma team receiving him in the resuscitation room.
On arrival he is sedated, intubated and ventilated. On primary survey, despite your best efforts, you cannot fully examine his eyes or pupillary response due to significant facial deformation.
He undergoes a CT trauma series from head to pelvis and is reported as having unilateral proptosis and retrobulbar haematoma which the radiologist reports as ‘suggestive of orbital compartment syndrome’. The receiving ICU team ask whether canthotomy and cantholysis should be performed before he is transferred for further management?
On arrival he is sedated, intubated and ventilated. On primary survey, despite your best efforts, you cannot fully examine his eyes or pupillary response due to significant facial deformation.
He undergoes a CT trauma series from head to pelvis and is reported as having unilateral proptosis and retrobulbar haematoma which the radiologist reports as ‘suggestive of orbital compartment syndrome’. The receiving ICU team ask whether canthotomy and cantholysis should be performed before he is transferred for further management?
Search Strategy:
Ovid MEDLINE(R) ALL
1 exp Orbit/ or exp Orbital Fractures/ or exp Compartment Syndromes/ or exp Retrobulbar Haem*/ or exp Retrobulbar Hem*/
2 exp Tomography/
3 1 and 2
4 cantho*.mp.
5 (blindness or vis* loss).mp.
6 4 or 5
7 3 and 6
Furthermore, we input the three-part question into AI powered search engine https://www.openevidence.com and reviewed the reference list.
The Cochrane Library (www.cochrane.org) was searched using “Orbital compartment syndrome”, “Orbital fracture” and “Canthotomy” which resulted in no relevant systematic Cochrane reviews.
1 exp Orbit/ or exp Orbital Fractures/ or exp Compartment Syndromes/ or exp Retrobulbar Haem*/ or exp Retrobulbar Hem*/
2 exp Tomography/
3 1 and 2
4 cantho*.mp.
5 (blindness or vis* loss).mp.
6 4 or 5
7 3 and 6
Furthermore, we input the three-part question into AI powered search engine https://www.openevidence.com and reviewed the reference list.
The Cochrane Library (www.cochrane.org) was searched using “Orbital compartment syndrome”, “Orbital fracture” and “Canthotomy” which resulted in no relevant systematic Cochrane reviews.
Search Details:
Only abstracts in English were reviewed
Outcome:
Ovid Medline search identified 330 studies. Following title and abstract screening most of the papers were excluded as irrelevant for the question as addressing non-traumatic presentations. 19 articles remained for full text review. Full text copies could not be retrieved or were not available in English for 2 articles. After full text review a total of 2 papers were relevant to the BestBET.
Review of reference list chosen by the AI search engine (n=7) resulted in paper by Maier et al. (2023) added for full review.
Review of reference list chosen by the AI search engine (n=7) resulted in paper by Maier et al. (2023) added for full review.
Relevant Paper(s):
| Study Title | Patient Group | Study type (level of evidence) | Outcomes | Key results | Study Weaknesses |
|---|---|---|---|---|---|
| Emergency management of orbital compartment syndrome: Lateral canthotomy and cantholysis case series Rebecca Ilona Peisah, Kevin Ostrowski March 2025 | Over 16-year-olds with suspected traumatic OCS subjected to lateral canthotomy (LCC) in a single trauma centre | Retrospective Observational Study | Demographics, mechanism of injury, timing and performance of canthotomy, CT imaging findings, examination findings, complications for LCC | • 20 patients received LCC, bilateral in one case, hence denominator 21 when describing CT findings | • Single centre • Not clear how the decision to perform LCC was made • Only 20 cases - 1 bilateral • Limited CT findings described |
| • 16/20 LCC performed without primary indications. | |||||
| • 20/20 had a CT scan | |||||
| • 17/20 had CT before LCC | |||||
| • 12/21 had retrobulbar hematoma | |||||
| • CT Findings were proptosis (16/21, 76%), infraorbital fat stranding (8/21, 62%), optic nerve stretching (6/21, 29% | |||||
| • EM performing 18/21 LCC | |||||
| • 7/20 didn’t recover vision to baseline despite LCC | |||||
| Incidence and outcomes of retrobulbar hematoma diagnosed by computed tomography in cases of orbital fracture Matthew Kondoff MSc, Georges Nassrallah MD, Michael Ross MD, Jean Deschênes MD October 2019 Canada | Patients with orbital fracture and CT diagnosed retrobulbar hematoma without globe rupture | Retrospective Observational Study | Demographics, presence of intra/extraconal hematoma, mechanism of injury, examination and intervention with LCC | • In 292 orbital fractures without globe rupture, 94 (32.1%) resulted in RBH | • Small patient group |
| • 1 case (1.1%) received LCC | |||||
| • 93/94 patients (99%) had no intervention for RBH | |||||
| Imaging the Tight Orbit: Radiologic Manifestations of Orbital Compartment Syndrome C Maier et al May 2023 America | Patients clinically diagnosed with OCS with cross- sectional imaging available before LCC at two academic trauma centres | Retrospective Observational Study | Demographics, mechanism of injury, examination, imaging findings | • 29 cases | • Heterogenous imaging protocols • Only clinically evident OCS were included |
| • In 3 cases, OCS was diagnosed after surgical intervention for craniofacial injuries | |||||
| • Active bleeding was observed in 50% who had contrast enhanced CT (7/14) | |||||
| • Superior ophthalmic vein was smaller than contralateral side in 20/29, larger in 1/29 | |||||
| • Proptosis, stretching of the optic nerve and decrease of the posterior globe angle were suggestive of OCS |
Author Commentary:
No studies were identified that directly answered our question. The studies that we have included are all retrospective observational studies with small patient groups. Only a single study by Peisah et al. (2025) investigated those suspected of having OCS, rather than having received a clinically evident diagnosis.
Available evidence demonstrates that clinical suspicion of orbital compartment syndrome is the principal trigger for performing LCC. However, clinical examination can be unreliable in the acutely traumatically injured patient with altered facial anatomy.
CT findings in orbital compartment syndrome include proptosis, optic nerve stretch, infraorbital fat stranding and decrease of posterior globe angle (Maier et al. (2023)). Whilst these findings are frequently present in OCS and may support clinical diagnosis, their exact sensitivity and specificity - either in isolation or combination - remain unknown. The recent study by Pesiah et al. (2025) suggests that as many as 2/3 of canthotomies are performed without meeting clinical criteria for optic nerve ischaemia, and some are performed taking CT findings into consideration. This study also showed that these procedures are mostly performed by EM specialists.
Another study by Kondoff et al (2019) found that only 1% of retrobulbar haematomas, often the precursor for OCS, will evolve into OCS requiring canthotomy. Importantly, this demonstrates that presence of retrobulbar haematoma alone does not necessarily mandate intervention.
Available evidence demonstrates that clinical suspicion of orbital compartment syndrome is the principal trigger for performing LCC. However, clinical examination can be unreliable in the acutely traumatically injured patient with altered facial anatomy.
CT findings in orbital compartment syndrome include proptosis, optic nerve stretch, infraorbital fat stranding and decrease of posterior globe angle (Maier et al. (2023)). Whilst these findings are frequently present in OCS and may support clinical diagnosis, their exact sensitivity and specificity - either in isolation or combination - remain unknown. The recent study by Pesiah et al. (2025) suggests that as many as 2/3 of canthotomies are performed without meeting clinical criteria for optic nerve ischaemia, and some are performed taking CT findings into consideration. This study also showed that these procedures are mostly performed by EM specialists.
Another study by Kondoff et al (2019) found that only 1% of retrobulbar haematomas, often the precursor for OCS, will evolve into OCS requiring canthotomy. Importantly, this demonstrates that presence of retrobulbar haematoma alone does not necessarily mandate intervention.
Bottom Line:
- The true incidence of orbital compartment syndrome is difficult to quantify
- Orbital trauma resulting in RBH may not always require treatment to preserve sight. However, research is needed to help risk-stratify this group.
- Certain CT findings are present in OCS indicative of sight threatening optic nerve damage but their precise sensitivity and specificity in the trauma population is unknown
- There are no tools to date for risk-stratification of RBH without clinically evident OCS, however current practices suggest LCC is being performed before optic nerve damage is clinically evident.
- Future work should focus on prospective imaging–clinical correlation studies to develop a risk stratification tool for OCS in blunt orbital trauma
- Orbital trauma resulting in RBH may not always require treatment to preserve sight. However, research is needed to help risk-stratify this group.
- Certain CT findings are present in OCS indicative of sight threatening optic nerve damage but their precise sensitivity and specificity in the trauma population is unknown
- There are no tools to date for risk-stratification of RBH without clinically evident OCS, however current practices suggest LCC is being performed before optic nerve damage is clinically evident.
- Future work should focus on prospective imaging–clinical correlation studies to develop a risk stratification tool for OCS in blunt orbital trauma
Level of Evidence:
Level 3: Small numbers of small studies or great heterogeneity or very different population
References:
- Rebecca Ilona Peisah, Kevin Ostrowski. Emergency management of orbital compartment syndrome: Lateral canthotomy and cantholysis case series
- Matthew Kondoff MSc, Georges Nassrallah MD, Michael Ross MD, Jean Deschênes MD. Incidence and outcomes of retrobulbar hematoma diagnosed by computed tomography in cases of orbital fracture
- C Maier et al. Imaging the Tight Orbit: Radiologic Manifestations of Orbital Compartment Syndrome