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Accuracy of linear-probe ultrasonography in diagnosis of infraorbital rim fractures

Abstract

Background

Maxillofacial fractures are a common cause of visits to emergency department, accounting for more than 400,000 annual visits in the United States. Gold standard diagnostic tool is conventional computerized tomography (CT) or 3DCT reconstruction. However, the disadvantages of CT are radiation exposure, unavailable in some hospital and expensiveness. Whereas the bony structures overlap is a problem in diagnostic when using plain film X-ray. The objective of this study is to show the accuracy of a linear-probe ultrasound compared to computed tomography and plain film X-ray in diagnosis of infraorbital rim fracture.

Methods

Patients clinically suspected of an inferior orbital rim fracture underwent linear-probe ultrasonographic investigation, plain film X-ray and CT. CT was used as gold standard in this diagnostic study. A radiologist and senior resident of plastic surgery were the examiner and interobserver for comparison.

Result

A total of 34 patients with suspected infraorbital rim fractures were investigated. Sensitivity of the linear-probe ultrasonography versus CT in the detection of infraorbital rim fracture was 92.9% (95% CI 66.1–99.8), specificity was 90.0% (95% CI 68.3–98.8), positive predictive value was 86.7% (95% CI 59.5–98.3), negative predictive value was 94.7% ( 95% CI 74.0–99.9), accuracy 91%.

Conclusion

Linear probe ultrasonography is a good diagnostic tool and has better reliability than the plain film X-ray and can be used as alternative to CT in inferior orbital rim fracture.

Background

Maxillofacial fractures are a common cause of emergency department (ED) visits, accounting for more than 400,000 annual visits in the United States alone [1], and occurs in approximately 5–33% of patients experiencing severe trauma [2, 3]. The incidence of maxillofacial trauma varies from region to region. Cause of injuries varies by age group, [4] and racial group; type of fractures also depends on the group studied [4, 5]. The most typical site of injury is zygomaticomaxillary complex (38.6%) [6]. 35% of zygomaticomaxillary complex fracture involve infraorbital rim [5, 7].

Clinical presentations of zygomaticomaxillary complex or infraorbital rim fractures are tenderness, periorbital ecchymosis, diplopia, ocular movement limitation, numbness of infraorbital area, nausea and vomiting in children [8,9,10]. Gold standard diagnostic tool is computerized tomography (CT) [11] by the coronal, axial plane with 1-mm thin-slice 3D reconstruction. However, CT scanning leads to radiation exposure, is expensive and not available in some hospitals. But the overlap of bony structures may not lead to correct diagnosis when using plain film X-ray.

Ultrasonography [12] is a widely available method that can be performed bedside in ED with no radiation exposure, and is inexpensive. Previous studies show the benefits of using ultrasonography as an alternative method for investigating facial fracture [9, 13,14,15]. Inferior orbital rim fracture can be diagnosed by using curved array ultrasound [16]. However, most of the ultrasound machines which have been used for trauma patients in ED do not have curved array, and mainly use a linear probe.

The objective of this study is to show the accuracy of a linear-probe ultrasound compared to CT and plain film X-ray in diagnosis of infraorbital rim fracture.

Material and methods

An institutional review board approved the study which was conducted between April of 2019 and May 2021 at Phramongkutklao hospital. Our diagnostic study compared the receiver operating characteristics (sensitivity, specificity, and positive predictive value (PPV) and negative predictive value (NPV)) of linear-probe ultrasound, plain film X-ray and 64-slice CT 3D of facial bone to determine the concordance between them in detecting inferior rim of zygomatic bone fracture.

The inclusion criteria consisted of patients aged 18 years or older who presented with a history of injury and had clinically suspected inferior orbital rim fracture which may include periorbital trauma, periorbital ecchymosis, diplopia, limited ocular movement, periorbital tenderness (especially in the infraorbital rim area), or numbness at infraorbital area. The exclusion criteria are obvious stepping at infraorbital area, other emergency condition such as ruptured globe, history of moderate-to-severe head injury, and unstable vital signs. All the participants provided written informed consent for participation in the study and publication of the photographs.

Our study protocol starts with bedside ultrasound (GE LOGIQ e 2012 with 7.5 MHz linear transducer), which was performed in ED, followed by collection of and data.

For the investigation of infraorbital rim fracture, the transducer was positioned at the infraorbital rim and the orbital rim with minimal pressure to look for any fracture line, while the patients were asked to close their eyes (Fig. 1). Plain film X-ray (PA and Waters’ view) and CT of facial bone with 3D bone reconstruction (Canon Lightning Aquilion 64 CT scan thin slice 1 mm.) were accomplished. A “positive case” for each of the methods used was defined as a discontinuity or displacement of bone cortex (Fig. 2). A “negative case” was defined as the absence of discontinuity or displacement of bone cortex. Imaging data of X-ray and ultrasound were interpreted by the senior resident plastic surgeon and staff radiologist, whereas CT was interpreted by staff radiologist before proceeding with the standard treatment (Figs. 3, 4).

Fig. 1
figure 1

Demonstrating the use of linear-probe ultrasound examination of infra orbital rim. A and B Demonstration using ultrasound for infraorbital rim examination

Fig. 2
figure 2

ab Demonstration of the discontinuation of infra orbital rim fracture site

Fig. 3
figure 3

ad Case of 42-year-old male: history of vehicle accident, presented with right infraorbital rim tenderness; diagnosed with fracture of right zygoma

Fig. 4
figure 4

ad Case of 33-year-old male: history of vehicle accident, presented with marked swelling of right periorbital area, no fracture of infra orbital rim detected

The categorical variables were summarized using percentages and frequency of occurrence. Descriptive statistics such as means, medians, ranges, and standard deviations were calculated to derive continuous variables such as sensitivity, specificity, PPV, and NPV of linear transducer ultrasound, plain film X-ray and CT 3D facial bone (set as gold standard) for comparison. P value of < 0.05 was considered significant. All statistical calculations were performed using SPSS version 22 (Chicago, IL).

Results

Thirty-four patients met the inclusion criteria. The study was completed in all patients. Patients demographics are summarized in Table 1. Most of patients were male (88 percent) and most of accidental cause were vehicle accident (67.6 percent). Most of patients were male (88%) and most of the causes were vehicle accidents (67.6%). Periorbital ecchymosis (88.2%) was the most common clinical appearance. All the patients underwent bedside linear transducer ultrasound, plain film X-ray and CT 3D of facial bone. Ten patients underwent an open reduction and internal fixation; 20 patients were treated conservatively, and four patients underwent a closed reduction.

Table 1 Baseline clinical characteristic of 34 patients

Sensitivity of the linear-probe ultrasonography, when compared to that of CT in the detection of infraorbital rim fracture was 92.9% (95% CI 66.1–99.8), specificity was 90.0% (95% CI 68.3–98.8), PPV was 86.7% (95% CI 59.5–98.3), NPV was 94.7% (95% CI 74.0–99.9), accuracy 91%. The sensitivity of plain film X-ray when compared to that of CT in the detection of infraorbital rim fracture was only 78% (95% CI 49.2–95.3), specificity was 80% (95% CI 56.3–94.3), PPV was 73.3% (95% CI 44.9–92.3) NPV was 84.2% (95% CI 60.4–96.6), accuracy 79% percent (Table 2).

Table 2 Sensitivity and specificity compared to computer tomography

The ultrasound diagnosis performed by the senior resident of plastic surgery and that of the staff of radiology department was compared. Sensitivity of senior resident of plastic surgery was 92.3% (95% CI 47.2–93.3), and that of the radiologist was 92.9% (95% CI 66.2–99.8). Specificity of senior resident of plastic surgery was 87% (95% CI 63.3–97.3), and that of the radiologist was 90% (95% CI 68.3–98.8); PPV of senior resident of plastic surgery was 84% (95% CI 48.6–96.7) and that of the radiologist was 86.7% (95% CI 59.5–98.3); NPV of senior resident of plastic surgery 90.2% (95% CI 69.4–97.6) and that of the radiologist was 94.7% (95% CI 47–99.9); accuracy of senior resident of plastic surgery 88% and that of the radiologist was 91% (Table 3).

Table 3 Performance between operators

Discussion

Inferior orbital rim is a part of zygomatic and maxillary bone and called as zygomaticomaxillary suture [17], this area contains infraorbital nerve which when injured or involved in fracture causes numbness in the infraorbital area [18]. Inferior orbital rim is one of the most common areas involving maxillofacial fracture; it may be a simple zygomatic bone fracture or severe multiple facial bone fractures or pan facial fracture. Clinical signs of inferior orbital rim fracture include swelling, periorbital ecchymosis, subconjunctival hemorrhage, and numbness [19, 20]. In our study, 88.2% of patients had periorbital ecchymosis, 64.7% had subconjunctival hemorrhage and 20.6% developed reduced sensation in the infraorbital area.

Actually, most definite clinical sign of fracture is clinical stepping. Fracture of the inferior orbital is easy to detect if swelling is not much, but most of patients present with swelling, which makes it difficult to examine and palpate the stepping area. The diagnosis of an orbital fracture is challenging because its clinical presentation usually varies and the anatomy of the region is complex [21,22,23]. Although the capability of a conventional non-contrast CT in providing multiplanar thin slices or 3D reconstruction of facial bone with good spatial resolution and 3D images in orbital fractures [24,25,26] makes it the imaging method of choice or accepted as gold standard [27,28,29], there is a significant concern regarding the hazard of radiation, and in some emergency situations clinical state of patient may not stable enough to be transferred to CT room. Financial issues could also be a matter of concern for some patients.

Ultrasound is a less invasive diagnostic tool with no radiation effect; it consists of high-frequency mechanical vibration not audible to human ear. Cost of ultrasound is also much less than that of CT. Ultrasound can be used in trauma patients, and most emergency departments have ultrasound for detecting cardiac tamponade of pericardial effusion or focus assessment sonography in trauma in abdominal injury. Ultrasound was first used as a diagnostic tool for maxillofacial fracture in 1981 by ORD et al. [30] to detect medial orbital wall fracture. Several authors have reported their studies [16, 31,32,33]. Most of studies used ultrasound in medial, lateral wall and orbital floor fracture. The least sensitivity for detection of medial and lateral wall orbit was 56% and 88%, respectively [32, 34], whereas the least specificity was 90% and 87%, respectively [31, 32]. The overall accuracy for the detection orbital wall fracture was 90–100% [9].

Fractures of the inferior orbital rim are easily detected by ultrasonography (35). The ultrasonography was performed with a 7.5 MHz curved array transducer with a sensitivity of 94% and a specificity of 92%, and a diagnostic accuracy of 92%. The positive predictive value (PPV negative predictive value (NPV) were 91% and 92%, respectively. We tested the performance of linear-probe ultrasound which is always available in ED and used for trauma patients. The diagnostic results in this study showed that a linear-probe ultrasound is not inferior to a curved array transducer; its sensitivity (92.9%), specificity (90%), PPV (86.7%), NPV (94.7%) and accuracy (79%) were significantly better than those of plain film X-ray.

This study compared the results obtained by a radiologist and senior plastic resident as examiners. Although ultrasonography is operator dependent and requires experienced personnel, there is very good interobserver reliability. Senior plastic resident may represent a non-boarded radiologist or general practitioner who practices in the ED and can use a linear probe to screen patients with clinically suspected infra orbital rim fracture during primary or secondary survey of advance trauma life support process. It has the advantage of screening in short duration of time and can performed in emergency room. The resident who participated in the study has said that they feel more confident when they have more experience while they performed using ultrasonography.

From the results, it could be concluded that ultrasonography is also helpful in screening and diagnosis of infraorbital rim fracture in some situations. It is particularly useful in a rural hospital where a confirmed diagnosis is necessary before transferring the patient to a hospital with government insurance. If the focus is only on inferior orbital rim, ultrasonography can replace plain film X-ray. Ultrasonography also can measure the gap and stepping of fracture site that can help to assess bone displacement. However, weakness of linear probe cannot detect the orbital floor fracture when compared with curvilinear array endocavity ultrasound, but it is rarely available in the emergency room. In severe orbital trauma or injuries to the skull and central nervous system, CT remains the standard option, because intra-cranial injuries and compressions of the optic nerve cannot be adequately evaluated by ultrasonography. Our study limitation is that we did not use intraoperative findings as a gold standard. In this regard, further studies may be required to provide acceptable results using US methodology.

Conclusions

Linear probe ultrasonography has better diagnostic performance and reliability than plain film X-ray and can be used as an alternative investigation tool to CT in inferior orbital rim fracture.

Data availability

The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.

Abbreviations

CT:

Computerized tomography

PPV:

Positive predictive value

NPV:

Negative predictive value

References

  1. Chukwulebe S, Hogrefe C (2019) The diagnosis and management of facial bone fractures. Emerg Med Clin North Am 37(1):137–151

    Article  PubMed  Google Scholar 

  2. Shahim FN, Cameron P, McNeil JJ (2006) Maxillofacial trauma in major trauma patients. Aust Dent J 51(3):225–230

    Article  CAS  PubMed  Google Scholar 

  3. Cavalcanti AL, Lino TH, de Oliveira TB, de Oliveira TS, Cardoso AM, de Macedo RF et al (2014) Head and maxillofacial injuries in child and adolescent victims of automotive accidents. ScientificWorldJournal 2014:632720

    Article  PubMed  PubMed Central  Google Scholar 

  4. Chiang E, Saadat LV, Spitz JA, Bryar PJ, Chambers CB (2016) Etiology of orbital fractures at a level I trauma center in a large metropolitan city. Taiwan J Ophthalmol 6(1):26–31

    Article  PubMed  PubMed Central  Google Scholar 

  5. Cruz AA, Eichenberger GC (2004) Epidemiology and management of orbital fractures. Curr Opin Ophthalmol 15(5):416–421

    Article  PubMed  Google Scholar 

  6. Pungrasmi P, Haetanurak S (2018) Incidence and etiology of maxillofacial trauma: a retrospective analysis of king Chulalongkorn memorial hospital in the past decade. Asian Biomed 11(4):353

    Article  Google Scholar 

  7. Chaudhry O, Isakson M, Franklin A, Maqusi S, El Amm C (2018) Facial fractures: pearls and perspectives. Plast Reconstr Surg 141(5):742e-e758

    Article  CAS  PubMed  Google Scholar 

  8. Caranci F, Cicala D, Cappabianca S, Briganti F, Brunese L, Fonio P (2012) Orbital fractures: role of imaging. Semin Ultrasound CT MR 33(5):385–391

    Article  PubMed  Google Scholar 

  9. Adeyemo WL, Akadiri OA (2011) A systematic review of the diagnostic role of ultrasonography in maxillofacial fractures. Int J Oral Maxillofac Surg 40(7):655–661

    Article  CAS  PubMed  Google Scholar 

  10. Jank S, Emshoff R, Etzelsdorfer M, Strobl H, Nicasi A, Norer B (2004) Ultrasound versus computed tomography in the imaging of orbital floor fractures. J Oral Maxillofac Surg 62(2):150–154

    Article  PubMed  Google Scholar 

  11. Johari M, Ghavimi MA, Mahmoudian H, Javadrashid R, Mirakhor Samani S, Fouladi DF (2016) A comparable study of the diagnostic performance of orbital ultrasonography and CBCT in patients with suspected orbital floor fractures. Dentomaxillofac Radiol 45(6):20150311

    Article  PubMed  PubMed Central  Google Scholar 

  12. Chrcanovic BR, Abreu MH, Custodio AL (2011) A morphometric analysis of supraorbital and infraorbital foramina relative to surgical landmarks. Surg Radiol Anat 33(4):329–335

    Article  PubMed  Google Scholar 

  13. Navaratnam R, Davis T (2019) The role of ultrasound in the diagnosis of pediatric nasal fractures. J Craniofac Surg 30(7):2099–2101

    Article  PubMed  Google Scholar 

  14. Friedrich RE, Heiland M, Bartel-Friedrich S (2003) Potentials of ultrasound in the diagnosis of midfacial fractures*. Clin Oral Investig 7(4):226–229

    Article  CAS  PubMed  Google Scholar 

  15. Buller J, Zirk M, Kreppel M, Maus V, Zöller JE (2019) Intraoperative ultrasound control of zygomatic arch fractures: does additional imaging improve reduction quality? J Oral Maxillofac Surg 77(4):769–776

    Article  PubMed  Google Scholar 

  16. Jank S, Emshoff R, Strobl H, Etzelsdorfer M, Nicasi A, Norer B (2004) Effectiveness of ultrasonography in determining medial and lateral orbital wall fractures with a curved-array scanner. J Oral Maxillofac Surg 62(4):451–455

    Article  PubMed  Google Scholar 

  17. Yu M, Wang SM. Anatomy, Head and Neck, Zygomatic. StatPearls. Treasure Island (FL): StatPearls Publishing Copyright © 2020, StatPearls Publishing LLC; 2020.

  18. Fogaça WC, Fereirra MC, Dellon AL (2004) Infraorbital nerve injury associated with zygoma fractures: documentation with neurosensory testing. Plast Reconstr Surg 113(3):834–838

    Article  PubMed  Google Scholar 

  19. Ellstrom CL, Evans GR (2013) Evidence-based medicine: zygoma fractures. Plast Reconstr Surg 132(6):1649–1657

    Article  CAS  PubMed  Google Scholar 

  20. Peretti N, MacLeod S (2017) Zygomaticomaxillary complex fractures: diagnosis and treatment. Curr Opin Otolaryngol Head Neck Surg 25(4):314–319

    Article  PubMed  Google Scholar 

  21. Joseph JM, Glavas IP (2011) Orbital fractures: a review. Clin Ophthalmol 5:95–100

    Article  PubMed  PubMed Central  Google Scholar 

  22. Boyette JR, Pemberton JD, Bonilla-Velez J (2015) Management of orbital fractures: challenges and solutions. Clin Ophthalmol 9:2127–2137

    Article  PubMed  PubMed Central  Google Scholar 

  23. Rhim CH, Scholz T, Salibian A, Evans GR (2010) Orbital floor fractures: a retrospective review of 45 cases at a tertiary health care center. Craniomaxillofac Trauma Reconstr 3(1):41–47

    Article  PubMed  PubMed Central  Google Scholar 

  24. Brisco J, Fuller K, Lee N, Andrew D (2014) Cone beam computed tomography for imaging orbital trauma–image quality and radiation dose compared with conventional multislice computed tomography. Br J Oral Maxillofac Surg 52(1):76–80

    Article  PubMed  Google Scholar 

  25. Lee HJ, Jilani M, Frohman L, Baker S (2004) CT of orbital trauma. Emerg Radiol 10(4):168–172

    Article  PubMed  Google Scholar 

  26. Holmgren EP, Dierks EJ, Homer LD, Potter BE (2004) Facial computed tomography use in trauma patients who require a head computed tomogram. J Oral Maxillofac Surg 62(8):913–918

    Article  PubMed  Google Scholar 

  27. McCann PJ, Brocklebank LM, Ayoub AF (2000) Assessment of zygomatico-orbital complex fractures using ultrasonography. Br J Oral Maxillofac Surg 38(5):525–529

    Article  CAS  PubMed  Google Scholar 

  28. Jenkins CN, Thuau H (1997) Ultrasound imaging in assessment of fractures of the orbital floor. Clin Radiol 52(9):708–711

    Article  CAS  PubMed  Google Scholar 

  29. Hwang K, Jung JS, Kim H (2018) Diagnostic performance of plain film, ultrasonography, and computed tomography in nasal bone fractures: a systematic review. Plast Surg 26(4):286–292

    Article  Google Scholar 

  30. Ord RA, Le May M, Duncan JG, Moos KF (1981) Computerized tomography and B-scan ultrasonography in the diagnosis of fractures of the medial orbital wall. Plast Reconstr Surg 67(3):281–288

    Article  CAS  PubMed  Google Scholar 

  31. Jank S, Deibl M, Strobl H, Oberrauch A, Nicasi A, Missmann M et al (2005) Interrater reliability of sonographic examinations of orbital fractures. Eur J Radiol 54(3):344–351

    Article  PubMed  Google Scholar 

  32. Jank S, Deibl M, Strobl H, Oberrauch A, Nicasi A, Missmann M et al (2006) Intrarater reliability in the ultrasound diagnosis of medial and lateral orbital wall fractures with a curved array transducer. J Oral Maxillofac Surg 64(1):68–73

    Article  PubMed  Google Scholar 

  33. Akizuki H, Yoshida H, Michi K (1990) Ultrasonographic evaluation during reduction of zygomatic arch fractures. J Craniomaxillofac Surg 18(6):263–266

    Article  CAS  PubMed  Google Scholar 

  34. Iinuma T, Hirota Y, Ishio K (1994) Orbital wall fractures Conventional views and CT. Rhinology 32(2):81–83

    CAS  PubMed  Google Scholar 

  35. Jank S, Emshoff R, Etzelsdorfer M, Strobl H, Nicasi A, Norer B (2004) The diagnostic value of ultrasonography in the detection of orbital floor fractures with a curved array transducer. Int J Oral Maxillofac Surg 33(1):13–18

    Article  CAS  PubMed  Google Scholar 

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Acknowledgements

The authors would like to acknowledge all patients and staff of Phramongkutklao Hospital.

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The authors indicated in parentheses made substantial contribution to the following tasks of research: initial conception (CP); design (CP); provision of resource (CP, NW, MP); collection of data (NW, MP); analysis and interpretation (CP, NW); writing and revision of paper (CP, NW) [Chatchai Pruksapong = CP, Nuttadon Wongprakob = NW, Minth Panphichet = MP]. All authors read and approved the final manuscript.

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Correspondence to Chatchai Pruksapong.

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Pruksapong, C., Wongprakob, N. & Panphichet, M. Accuracy of linear-probe ultrasonography in diagnosis of infraorbital rim fractures. Ultrasound J 15, 9 (2023). https://doi.org/10.1186/s13089-022-00298-y

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