- Email: [email protected]
Comparison of ultrasonography with conventional radiography in the diagnosis of zygomatic complex fractures
Accepted Manuscript Comparison of ultrasonography with conventional radiography in the diagnosis of zygomatic complex fractures Rahul P. Menon, Dr. Resident, S.K. Roy Chowdhury, Dr. Professor, R.S. Semi, Dr. Senior Specialist, Vishal Gupta, Dr. Associate Professor, Serat Rahman, Dr. Lecturer, T. Balasundaram, Dr. Resident PII:
S1010-5182(16)00030-5
DOI:
10.1016/j.jcms.2016.01.016
Reference:
YJCMS 2288
To appear in:
Journal of Cranio-Maxillo-Facial Surgery
Received Date: 21 October 2015 Revised Date:
1 January 2016
Accepted Date: 26 January 2016
Please cite this article as: Menon RP, Chowdhury SKR, Semi RS, Gupta V, Rahman S, Balasundaram T, Comparison of ultrasonography with conventional radiography in the diagnosis of zygomatic complex fractures, Journal of Cranio-Maxillofacial Surgery (2016), doi: 10.1016/j.jcms.2016.01.016. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
ACCEPTED MANUSCRIPT
Comparison of ultrasonography with conventional radiography in the diagnosis of zygomatic complex fractures Rahul P. Menon$, S.K. Roy Chowdhury*, R.S. Semi†, Vishal Gupta+, Serat Rahman‡, T.
RI PT
Balasundaram**
$- Resident, Department of Oral and Maxillofacial Surgery, Army Dental Centre (Research and
SC
Referral)
*- Professor, Department of Oral and Maxillofacial Surgery, Army Dental Centre (Research and
M AN U
Referral)
†- Senior Specialist, Department of Oral and Maxillofacial Surgery, Army Dental Centre (Research and Referral)
+- Associate Professor, Department of Oral and Maxillofacial Surgery, Army Dental Centre
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(Research and Referral)
‡- Lecturer, Department of Oral and Maxillofacial Surgery, Army Dental Centre (Research and Referral)
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Referral)
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**- Resident, Department of Oral and Maxillofacial Surgery, Army Dental Centre (Research and
Address for Correspondence: 1.
Dr. Rahul P Menon, (Primary Author)
Resident,
Dept of Oral and Maxillofacial Surgery, Army Dental Centre (Research and Referral),
ACCEPTED MANUSCRIPT
Delhi Cantt, New Delhi – 110010
Professor, Dept of Oral and Maxillofacial Surgery, Army Dental Centre (Research and Referral), Delhi Cantt, New Delhi – 110010
3. Dr. RS Semi Senior Specialist,
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Dept of Oral and Maxillofacial Surgery,
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Email: [email protected], [email protected]
Army Dental Centre (Research and Referral), Delhi Cantt, New Delhi – 110010
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Email: [email protected]
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4. Dr. Vishal Gupta Associate Professor,
Dept of Oral and Maxillofacial Surgery, Army Dental Centre (Research and Referral), Delhi Cantt, New Delhi – 110010 Emai: [email protected]
SC
2. Dr. SK Roy Chowdhury
RI PT
Email: [email protected]
ACCEPTED MANUSCRIPT
5. Dr. Serat Rahman
Dept of Oral and Maxillofacial Surgery, Army Dental Centre (Research and Referral), Delhi Cantt, New Delhi – 110010
Resident, Dept of Oral and Maxillofacial Surgery,
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6. Dr. T Balasundaram
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Email: [email protected]
Army Dental Centre (Research and Referral),
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Delhi Cantt, New Delhi – 110010
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EP
Email: [email protected]
RI PT
Senior Lecturer,
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Summary
Purpose: Zygomatic complex fractures have changed in patterns of occurrence, severity, and,
RI PT
more importantly, in the mode of injury. Protection of the globe and maintaining the width of the face are the more important roles of the complex. Diagnosis and treatment planning of such fractures become imperative in the sequencing of repair if and where indicated, especially in the
SC
case of isolated zygomatic complex fractures. Exploring the versatility of ultrasonography (US), in diagnosing zygomatic complex fractures in comparison to conventional radiography in a
M AN U
double-blind study, the objective of this study was to evaluate the efficacy of US and to explore the possibility of making US examination a mainstay in the primary diagnosis of such fractures.
Material and Method: The prospective, double-blind study design included 32 patients
TE D
suspected of having sustained isolated zygomatic complex fractures. The patients underwent US examination and radiographic examination in the form of paranasal sinus (PNS) and
EP
submentovertex (SMV) views for comparison.
Results: A sensitivity of 100% was seen in favor of US in the areas of the frontozygomatic
AC C
suture (FZ), arch, infraorbital, and buttress areas. Statistically significant differences (p < .01) was seen in areas of the arch and buttress region and in the infraorbital area.
Conclusion: Although US showed 100% sensitivity in detection of fracture lines at three articulations of the four that make up the zygomatic complex, it lacked in quantifying the amount
ACCEPTED MANUSCRIPT
and degree of displacement of the fractured segments, which hampered accurate treatment
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EP
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SC
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planning.
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INTRODUCTION
Assessment of the extent of trauma to the zygomatic complex and fractures at other additional
RI PT
associated sites becomes difficult particularly when displacement exists around a vertical axis of rotation. Hence the assessment of the fracture(s) and its displacement (if any) becomes
SC
paramount in the treatment planning of such fractures 1, 11.
Conventionally, the diagnosis of such fractures was done using radiographs such as those of the
M AN U
sub-mentovertex view (SMV) and the para-nasal sinus (PNS) view. Such modalities come with their own limitations, such as superimposition of adjacent anatomic structures and radiopaque implants in the vicinity of the area of interest, which may produce artifacts in the resultant image. The film-based modality also provided only a two-dimensional representation of the fractures,
TE D
which became more relevant in cases of comminution. In addition, radiation exposure to the patient is an important factor that needs to be considered 15.
EP
Ultrasonography (US) was first applied in the medical field in 1953 by Karl Theo Dussik7,8 for the detection and diagnosis of soft tissue swellings that arose from deeper cavities of the human
AC C
body. The high degree of specificity and sensitivity spurred further studies into the extended application of US as a diagnostic/affirmative aid in modern medical and surgical practice 3,5 .
If US were to prove to be as useful in the diagnosis of fractures of larger bones such as the zygomatic complex, it could be a useful and noninvasive adjunct to conventional radiographs, possibly replacing them as a first-line modality in the diagnosis of such conditions.
ACCEPTED MANUSCRIPT
This study aimed to explore the versatility of ultrasonography, which has thus far been a seldomused modality for the diagnosis of fractures of the zygomatic complex in comparison to the time-
RI PT
tested modality of conventional radiography. The study design formulated was double-blind, in which neither the sonologist nor the radiologist was aware of the findings, thus providing an
SC
impartial diagnosis.
The main objective of this study was to evaluate the efficacy of US in comparison to
M AN U
conventional radiography in the diagnosis of zygomatic complex fractures with computed tomography (CT) scans serving as the established gold standard.
TE D
MATERIAL AND METHODS
This study was conducted in an Armed Forces Tertiary care center from August 2013 to March 2015. Armed forces personnel (both serving and retired) and their dependents who were
EP
diagnosed with facial trauma were examined, and only those suspected of having sustained isolated zygomatic complex fractures were included in this study. Both sexes were part of this
AC C
study, with an age group ranging from 18 to 62 years. Individuals with residual deformities and mal-united fractures were not included in this study. All patients satisfying the above criteria who were entitled to treatment at this facility were included in this study.
The protocol for this study included recommended imaging in the form of plain radiographs (PNS and SMV). All subjects also underwent US examination of the affected region by the same
ACCEPTED MANUSCRIPT
sonologist using HDI 500 SONO CT (Phillips Healthcare Services) with a 7.5-MHz transducer. Sonography was used in the region of the zygomaticofrontal process, zygomatico maxillary process, zygomaticotemporal process, and the body of the zygoma. Plain radiography (PNS and
RI PT
SMV) views were interpreted by the radiologist. Each patient also underwent CT examination of the head and neck as per the standard protocol to rule out associated concomitant intra-cranial and cervical spine injuries. The CT images also served as the established gold standard for
SC
comparison with regard to the sensitivity and specificity of US and conventional radiographs.
M AN U
The observations were entered on an Microsoft Excel (Microsoft Corporation, Redmond, WA, USA) spreadsheet with columns and rows for each modality. The presence of a fracture was denoted by the letter “Y” and the absence of a fracture by the letter “N”. The data obtained were
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then subjected to statistical analysis with the χ2 test and Fisher exact test.
RESULTS
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A total of 32 patients were examined as described above, including 22 male and 10 female
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patients between the ages of 18 and 62 years.
A comparison between US, radiography, and CT at the FZ process are shown in Table 1 and revealed a difference that was not statistically significant (p = .206). However, it was noted that the sensitivity of US was 100% comparable to that of CT and far greater than that of plain radiography (58%), with a specificity of 100%, which was the same as with CT.
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The zygomatic arch revealed a great difference on comparison that was statistically significant (p < .01) (Table 1) in favor of US and sensitivity being 100% as compared to plain radiography, which showed a dismal sensitivity of 59%. Here again, the data collected showed results
RI PT
comparable to those of CT. The sensitivity of US in this area was found to be100%, which was the same as seen with CT.
SC
In the infra-orbital area, although there was a difference in significance noted with p = .82 (>.01) (Table 1), it was not deemed statistically significant; however, as with the previous anatomical
M AN U
locations, the sensitivity of US was comparable with that of CT at 92%, while that of plain radiography was 50%.
It is pertinent to note, however, that when it came to the zygomatic buttress region, the p value
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was >.01 and in favor of US (Table 1), which was also reflected in the comparison with CT. The sensitivity of radiography in detecting fractures at the buttress was far less than with US (48%
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EP
and 86%, respectively).
DISCUSSION
Zygomatic complex fractures, when displaced, regardless of the degree of displacement, are given special attention during the reduction and fixation procedures due to the protective and esthetic function served. However, the complexity in achieving the ideal result is compounded by the fragile architecture of the bone and also its complex articulations and muscle attachments.
ACCEPTED MANUSCRIPT
More often than not, it is these relations that lead to fair amount of displacement and comminution, rendering the reduction and fixation a challenge.
RI PT
Ultrasound is cyclic sound pressure traveling at frequencies greater than the upper limit of
human hearing (>20 kHz in healthy young adults). Most medical US equipment operates at frequencies in the range from 1 to 15 MHz, whereas therapeutic applications are usually
SC
restricted to the lower frequencies of this range (usually around 1 MHz).
M AN U
All patients in this study underwent conventional radiographic examination for the affected region in the form of PNS and SMV views, followed by US examination as per the stipulations mentioned earlier. The control was served by the unaffected side to differentiate between suture lines and fracture lines. As a part of this department’s protocol, the individuals were also
TE D
subjected to CT scans of the affected region, which served as the gold standard for comparison.
There was an increased incidence of fractures occurring in males as compared to females (n = 22
EP
and n = 10, respectively), which can be attributed to the social norms and vehicle driving
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practices within the study population.
In the FZ region, the comparison between the X-ray and US group yielded a statistical difference (p = .101) that was not significant; however, the sensitivity of US was found to be 100% as compared to 58% with radiography, which is contradictory to the study done by McCann4 et al., which reported a sensitivity of 82%, and that of Ogunmuyiwa13 with a dismal 25%. In contrast,
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our results were comparable to that of Forrest Christopher,14 who reported a sensitivity of 96% in this regard.
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The zygomatic arch evaluation revealed a statistical significance in favor of US with a p value of <.01 and again a sensitivity of 100%, as compared to that of radiography, which was 59%. These findings were also corroborated by earlier studies done by McCann4, Forrest14, and Friedrich4.
SC
These results are however seen as a corollary to the findings of Blessman2 et al., who shared a similar experience but reported better and more specific results with displaced fractures as
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compared to nondisplaced fractures. The results were closely similar to those achieved by Nezafati12 and Ogunmuyiwa13 in their comparative studies using the same parameters where they found that ultrasound was accurate in assessing the fractured arches with sensitivity of 88.2%
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and specificity of 100% in both cases.
In regard to the maxillary process of the zygomatic bone in the infra-orbital area, although there was a difference (p = .82), it was not found to be statistically significant. The variance in the
EP
same may be attributed to the fact that there is better visualization of anatomical structures in radiographs seen in digitally produced films as compared to the conventional cassette where
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scattered radiation and human error in developing the images plays a huge role in the final outcome. That being said, it should also be kept in mind that even though the clarity of digitally processed films is better, the overlapping of anatomical structures for a given projection are the same provided that standardization principles are strictly adhered to. On the other hand, US recordings are done using a probe that is run over the affected area with some amount of physical pressure, which can result in pain to the individual and thereby limit and sometimes even hamper
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the production of high-clarity images. The rate of greater accuracy in determining the presence of fracture was seen in US, with a sensitivity of 100%, which is more than the 90% observed by Ogunmuyiwa13. The results obtained at this location were similar to the studies conducted
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previously; although they were not as statistically significant, but the sensitivity was the same as noted in those studies 4,14,2,10,12.
SC
Adeyemo and Akadiri1 conducted a systematic review of the diagnostic role of US in
maxillofacial fractures in 2011. They performed a computerized search on MEDLINE and
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PubMed for publications in English on diagnostic US imaging in maxillofacial fractures. Seven articles between 1992 and 2009 were reviewed. The investigators found that specificity of US in detecting orbital fractures was between 56% and 100%, while that of nasal fractures was between 98% and 100% and for zygomatic fractures the sensitivity was in the range of 91% to
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96%. They concluded that there was much evidence to suggest the use of diagnostic US in maxillofacial fractures, especially those involving orbital, nasal, and zygomatic fractures, above all with the sensitivity and specificity for US being comparable to that of CT. These findings
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EP
were echoed in our study.
CONCLUSION
Keeping in mind the limitations of this study, we conclude by submitting that although US shows 100% sensitivity in the detection of fracture lines at three of the four bones that make up the zygomatic complex, US was efficient enough to detect single and multiple fracture lines in a
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given area. Its ability to quantify the displacement or even to indicate the axis of rotation of fractured segments (when present) and even overlapping by displaced segments, was found to be lacking. Even so, the advantage of US in providing real-time images obviates the need for
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radiographic imaging, making it an indispensable and versatile tool in the accident and
emergency setting, particularly in polytrauma situations in which a combined multi-disciplinary approach and timely intervention will reduce the need for repeated exposure to general
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Conflict of interest
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anesthesia and accompanying morbidity.
None.
Funding
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None.
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REFERENCES
1. Adeyemo WL, Akadiri OA. A systematic review of the diagnostic role of
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ultrasonography in maxillofacial fractures. Int J Maxillofacial Surg. 2011; 40: 655-661.
2. Blessman M, et al. Validation of a new tool for ultrasound as a diagnostic modality in
SC
suspected midfacial fractures. Int J Oral Maxillofac Surg. 2007; 36: 501-506.
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3. Danter J, et al. Ultrasound imaging of nasal bone fractures with a 20-MHz ultrasound scanner. Klinik für Hals-, Nasen- und Ohrenheilkunde, Medizinischen Universität zu Lübeck. HNO 1996; 44: 324-328.
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4. Friedrich RE, et al. Potential of ultrasound in the diagnosis of midfacial fractures. Clin Oral Investig. 2003; 7: 226-229.
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5. Akizuki H, et al. Comparison between conventional radiography and ultrasound in the
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diagnosis of zygomatic complex fractures. Cranio-Maxillo-Fac Surg. 1990; 18: 263-266.
6. Rabiner JE, et al. Accuracy of point-of-care ultrasonography for diagnosis of elbow fractures in children. Ann Emerg Med. 2013; 61: 9-17.
7. Dussik K. The ultrasonic field as a medical tool. Am J Phys Med. 1954; 33: 5-20.
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8. Dussik KT. Measurements of articular tissue with ultrasound. Am J Phys Med. 1958; 37: 160-165.
RI PT
9. Ludwig GD, Struthers FW. Considerations underlying the use of ultrasound to detect gallstones and foreign bodies in tissue. Naval Medical Research Institute Reports, Project #004 001, Report No. 4, June 1949.
SC
10. Lee MH, et al. Comparison of high-resolution ultrasonography and computed
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tomography in the diagnosis of nasal fractures. J Ultrasound Med 2009; 28: 6717-6723.
11. Rowe, Williams. Maxillofacial injuries. 1994; 1: 157-284.
12. Nezafati S, et al. Comparison of ultrasonography with submentovertex films and
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computed tomography scan in the diagnosis of zygomatic arch fractures. Dentomaxillofac Radiol. 2010; 39: 11-16.
EP
13. Ogunmuyiwa SA, et al. The validity of ultrasonography in the diagnosis of
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zygomaticomaxillary complex fractures. I J Oral Maxillofac Surg 2012; 41: 500-505.
14. Jank S. Ultrasound versus computed tomography in the imaging of orbital floor fractures. J Oral Maxillofac Surg. 2004; 62: 150-154.
15. White, Pharoah. Textbook on Radiology. 6th ed. Elsevier: 2009; 185-187.
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Region of zygomatic complex
p Value
1.
Fronto-zygomatic region
.206
2.
Zygomatic arch
.000
3.
Infra-orbital region
.115
4.
Zygomatic buttress region
.000
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Sl. No.
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Table 1. Region imaged and statistical significance
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Fig 1: USG scan at Lt FZ region demonstrating fracture
Fig 2: Control scan unaffected Rt side of same patient
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Fig 3: PNS view of same patient demonstrating intact FZ suture regions bilaterally
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Fig 4: transvaginal probe used for imaging of zygomatic buttress
Fig 5: Placement of USG probe at zygomatic arch area
S1010-5182(16)00030-5
DOI:
10.1016/j.jcms.2016.01.016
Reference:
YJCMS 2288
To appear in:
Journal of Cranio-Maxillo-Facial Surgery
Received Date: 21 October 2015 Revised Date:
1 January 2016
Accepted Date: 26 January 2016
Please cite this article as: Menon RP, Chowdhury SKR, Semi RS, Gupta V, Rahman S, Balasundaram T, Comparison of ultrasonography with conventional radiography in the diagnosis of zygomatic complex fractures, Journal of Cranio-Maxillofacial Surgery (2016), doi: 10.1016/j.jcms.2016.01.016. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
ACCEPTED MANUSCRIPT
Comparison of ultrasonography with conventional radiography in the diagnosis of zygomatic complex fractures Rahul P. Menon$, S.K. Roy Chowdhury*, R.S. Semi†, Vishal Gupta+, Serat Rahman‡, T.
RI PT
Balasundaram**
$- Resident, Department of Oral and Maxillofacial Surgery, Army Dental Centre (Research and
SC
Referral)
*- Professor, Department of Oral and Maxillofacial Surgery, Army Dental Centre (Research and
M AN U
Referral)
†- Senior Specialist, Department of Oral and Maxillofacial Surgery, Army Dental Centre (Research and Referral)
+- Associate Professor, Department of Oral and Maxillofacial Surgery, Army Dental Centre
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(Research and Referral)
‡- Lecturer, Department of Oral and Maxillofacial Surgery, Army Dental Centre (Research and Referral)
AC C
Referral)
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**- Resident, Department of Oral and Maxillofacial Surgery, Army Dental Centre (Research and
Address for Correspondence: 1.
Dr. Rahul P Menon, (Primary Author)
Resident,
Dept of Oral and Maxillofacial Surgery, Army Dental Centre (Research and Referral),
ACCEPTED MANUSCRIPT
Delhi Cantt, New Delhi – 110010
Professor, Dept of Oral and Maxillofacial Surgery, Army Dental Centre (Research and Referral), Delhi Cantt, New Delhi – 110010
3. Dr. RS Semi Senior Specialist,
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Dept of Oral and Maxillofacial Surgery,
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Email: [email protected], [email protected]
Army Dental Centre (Research and Referral), Delhi Cantt, New Delhi – 110010
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Email: [email protected]
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4. Dr. Vishal Gupta Associate Professor,
Dept of Oral and Maxillofacial Surgery, Army Dental Centre (Research and Referral), Delhi Cantt, New Delhi – 110010 Emai: [email protected]
SC
2. Dr. SK Roy Chowdhury
RI PT
Email: [email protected]
ACCEPTED MANUSCRIPT
5. Dr. Serat Rahman
Dept of Oral and Maxillofacial Surgery, Army Dental Centre (Research and Referral), Delhi Cantt, New Delhi – 110010
Resident, Dept of Oral and Maxillofacial Surgery,
M AN U
6. Dr. T Balasundaram
SC
Email: [email protected]
Army Dental Centre (Research and Referral),
TE D
Delhi Cantt, New Delhi – 110010
AC C
EP
Email: [email protected]
RI PT
Senior Lecturer,
ACCEPTED MANUSCRIPT
Summary
Purpose: Zygomatic complex fractures have changed in patterns of occurrence, severity, and,
RI PT
more importantly, in the mode of injury. Protection of the globe and maintaining the width of the face are the more important roles of the complex. Diagnosis and treatment planning of such fractures become imperative in the sequencing of repair if and where indicated, especially in the
SC
case of isolated zygomatic complex fractures. Exploring the versatility of ultrasonography (US), in diagnosing zygomatic complex fractures in comparison to conventional radiography in a
M AN U
double-blind study, the objective of this study was to evaluate the efficacy of US and to explore the possibility of making US examination a mainstay in the primary diagnosis of such fractures.
Material and Method: The prospective, double-blind study design included 32 patients
TE D
suspected of having sustained isolated zygomatic complex fractures. The patients underwent US examination and radiographic examination in the form of paranasal sinus (PNS) and
EP
submentovertex (SMV) views for comparison.
Results: A sensitivity of 100% was seen in favor of US in the areas of the frontozygomatic
AC C
suture (FZ), arch, infraorbital, and buttress areas. Statistically significant differences (p < .01) was seen in areas of the arch and buttress region and in the infraorbital area.
Conclusion: Although US showed 100% sensitivity in detection of fracture lines at three articulations of the four that make up the zygomatic complex, it lacked in quantifying the amount
ACCEPTED MANUSCRIPT
and degree of displacement of the fractured segments, which hampered accurate treatment
AC C
EP
TE D
M AN U
SC
RI PT
planning.
ACCEPTED MANUSCRIPT
INTRODUCTION
Assessment of the extent of trauma to the zygomatic complex and fractures at other additional
RI PT
associated sites becomes difficult particularly when displacement exists around a vertical axis of rotation. Hence the assessment of the fracture(s) and its displacement (if any) becomes
SC
paramount in the treatment planning of such fractures 1, 11.
Conventionally, the diagnosis of such fractures was done using radiographs such as those of the
M AN U
sub-mentovertex view (SMV) and the para-nasal sinus (PNS) view. Such modalities come with their own limitations, such as superimposition of adjacent anatomic structures and radiopaque implants in the vicinity of the area of interest, which may produce artifacts in the resultant image. The film-based modality also provided only a two-dimensional representation of the fractures,
TE D
which became more relevant in cases of comminution. In addition, radiation exposure to the patient is an important factor that needs to be considered 15.
EP
Ultrasonography (US) was first applied in the medical field in 1953 by Karl Theo Dussik7,8 for the detection and diagnosis of soft tissue swellings that arose from deeper cavities of the human
AC C
body. The high degree of specificity and sensitivity spurred further studies into the extended application of US as a diagnostic/affirmative aid in modern medical and surgical practice 3,5 .
If US were to prove to be as useful in the diagnosis of fractures of larger bones such as the zygomatic complex, it could be a useful and noninvasive adjunct to conventional radiographs, possibly replacing them as a first-line modality in the diagnosis of such conditions.
ACCEPTED MANUSCRIPT
This study aimed to explore the versatility of ultrasonography, which has thus far been a seldomused modality for the diagnosis of fractures of the zygomatic complex in comparison to the time-
RI PT
tested modality of conventional radiography. The study design formulated was double-blind, in which neither the sonologist nor the radiologist was aware of the findings, thus providing an
SC
impartial diagnosis.
The main objective of this study was to evaluate the efficacy of US in comparison to
M AN U
conventional radiography in the diagnosis of zygomatic complex fractures with computed tomography (CT) scans serving as the established gold standard.
TE D
MATERIAL AND METHODS
This study was conducted in an Armed Forces Tertiary care center from August 2013 to March 2015. Armed forces personnel (both serving and retired) and their dependents who were
EP
diagnosed with facial trauma were examined, and only those suspected of having sustained isolated zygomatic complex fractures were included in this study. Both sexes were part of this
AC C
study, with an age group ranging from 18 to 62 years. Individuals with residual deformities and mal-united fractures were not included in this study. All patients satisfying the above criteria who were entitled to treatment at this facility were included in this study.
The protocol for this study included recommended imaging in the form of plain radiographs (PNS and SMV). All subjects also underwent US examination of the affected region by the same
ACCEPTED MANUSCRIPT
sonologist using HDI 500 SONO CT (Phillips Healthcare Services) with a 7.5-MHz transducer. Sonography was used in the region of the zygomaticofrontal process, zygomatico maxillary process, zygomaticotemporal process, and the body of the zygoma. Plain radiography (PNS and
RI PT
SMV) views were interpreted by the radiologist. Each patient also underwent CT examination of the head and neck as per the standard protocol to rule out associated concomitant intra-cranial and cervical spine injuries. The CT images also served as the established gold standard for
SC
comparison with regard to the sensitivity and specificity of US and conventional radiographs.
M AN U
The observations were entered on an Microsoft Excel (Microsoft Corporation, Redmond, WA, USA) spreadsheet with columns and rows for each modality. The presence of a fracture was denoted by the letter “Y” and the absence of a fracture by the letter “N”. The data obtained were
TE D
then subjected to statistical analysis with the χ2 test and Fisher exact test.
RESULTS
EP
A total of 32 patients were examined as described above, including 22 male and 10 female
AC C
patients between the ages of 18 and 62 years.
A comparison between US, radiography, and CT at the FZ process are shown in Table 1 and revealed a difference that was not statistically significant (p = .206). However, it was noted that the sensitivity of US was 100% comparable to that of CT and far greater than that of plain radiography (58%), with a specificity of 100%, which was the same as with CT.
ACCEPTED MANUSCRIPT
The zygomatic arch revealed a great difference on comparison that was statistically significant (p < .01) (Table 1) in favor of US and sensitivity being 100% as compared to plain radiography, which showed a dismal sensitivity of 59%. Here again, the data collected showed results
RI PT
comparable to those of CT. The sensitivity of US in this area was found to be100%, which was the same as seen with CT.
SC
In the infra-orbital area, although there was a difference in significance noted with p = .82 (>.01) (Table 1), it was not deemed statistically significant; however, as with the previous anatomical
M AN U
locations, the sensitivity of US was comparable with that of CT at 92%, while that of plain radiography was 50%.
It is pertinent to note, however, that when it came to the zygomatic buttress region, the p value
TE D
was >.01 and in favor of US (Table 1), which was also reflected in the comparison with CT. The sensitivity of radiography in detecting fractures at the buttress was far less than with US (48%
AC C
EP
and 86%, respectively).
DISCUSSION
Zygomatic complex fractures, when displaced, regardless of the degree of displacement, are given special attention during the reduction and fixation procedures due to the protective and esthetic function served. However, the complexity in achieving the ideal result is compounded by the fragile architecture of the bone and also its complex articulations and muscle attachments.
ACCEPTED MANUSCRIPT
More often than not, it is these relations that lead to fair amount of displacement and comminution, rendering the reduction and fixation a challenge.
RI PT
Ultrasound is cyclic sound pressure traveling at frequencies greater than the upper limit of
human hearing (>20 kHz in healthy young adults). Most medical US equipment operates at frequencies in the range from 1 to 15 MHz, whereas therapeutic applications are usually
SC
restricted to the lower frequencies of this range (usually around 1 MHz).
M AN U
All patients in this study underwent conventional radiographic examination for the affected region in the form of PNS and SMV views, followed by US examination as per the stipulations mentioned earlier. The control was served by the unaffected side to differentiate between suture lines and fracture lines. As a part of this department’s protocol, the individuals were also
TE D
subjected to CT scans of the affected region, which served as the gold standard for comparison.
There was an increased incidence of fractures occurring in males as compared to females (n = 22
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and n = 10, respectively), which can be attributed to the social norms and vehicle driving
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practices within the study population.
In the FZ region, the comparison between the X-ray and US group yielded a statistical difference (p = .101) that was not significant; however, the sensitivity of US was found to be 100% as compared to 58% with radiography, which is contradictory to the study done by McCann4 et al., which reported a sensitivity of 82%, and that of Ogunmuyiwa13 with a dismal 25%. In contrast,
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our results were comparable to that of Forrest Christopher,14 who reported a sensitivity of 96% in this regard.
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The zygomatic arch evaluation revealed a statistical significance in favor of US with a p value of <.01 and again a sensitivity of 100%, as compared to that of radiography, which was 59%. These findings were also corroborated by earlier studies done by McCann4, Forrest14, and Friedrich4.
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These results are however seen as a corollary to the findings of Blessman2 et al., who shared a similar experience but reported better and more specific results with displaced fractures as
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compared to nondisplaced fractures. The results were closely similar to those achieved by Nezafati12 and Ogunmuyiwa13 in their comparative studies using the same parameters where they found that ultrasound was accurate in assessing the fractured arches with sensitivity of 88.2%
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and specificity of 100% in both cases.
In regard to the maxillary process of the zygomatic bone in the infra-orbital area, although there was a difference (p = .82), it was not found to be statistically significant. The variance in the
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same may be attributed to the fact that there is better visualization of anatomical structures in radiographs seen in digitally produced films as compared to the conventional cassette where
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scattered radiation and human error in developing the images plays a huge role in the final outcome. That being said, it should also be kept in mind that even though the clarity of digitally processed films is better, the overlapping of anatomical structures for a given projection are the same provided that standardization principles are strictly adhered to. On the other hand, US recordings are done using a probe that is run over the affected area with some amount of physical pressure, which can result in pain to the individual and thereby limit and sometimes even hamper
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the production of high-clarity images. The rate of greater accuracy in determining the presence of fracture was seen in US, with a sensitivity of 100%, which is more than the 90% observed by Ogunmuyiwa13. The results obtained at this location were similar to the studies conducted
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previously; although they were not as statistically significant, but the sensitivity was the same as noted in those studies 4,14,2,10,12.
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Adeyemo and Akadiri1 conducted a systematic review of the diagnostic role of US in
maxillofacial fractures in 2011. They performed a computerized search on MEDLINE and
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PubMed for publications in English on diagnostic US imaging in maxillofacial fractures. Seven articles between 1992 and 2009 were reviewed. The investigators found that specificity of US in detecting orbital fractures was between 56% and 100%, while that of nasal fractures was between 98% and 100% and for zygomatic fractures the sensitivity was in the range of 91% to
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96%. They concluded that there was much evidence to suggest the use of diagnostic US in maxillofacial fractures, especially those involving orbital, nasal, and zygomatic fractures, above all with the sensitivity and specificity for US being comparable to that of CT. These findings
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were echoed in our study.
CONCLUSION
Keeping in mind the limitations of this study, we conclude by submitting that although US shows 100% sensitivity in the detection of fracture lines at three of the four bones that make up the zygomatic complex, US was efficient enough to detect single and multiple fracture lines in a
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given area. Its ability to quantify the displacement or even to indicate the axis of rotation of fractured segments (when present) and even overlapping by displaced segments, was found to be lacking. Even so, the advantage of US in providing real-time images obviates the need for
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radiographic imaging, making it an indispensable and versatile tool in the accident and
emergency setting, particularly in polytrauma situations in which a combined multi-disciplinary approach and timely intervention will reduce the need for repeated exposure to general
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Conflict of interest
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anesthesia and accompanying morbidity.
None.
Funding
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None.
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REFERENCES
1. Adeyemo WL, Akadiri OA. A systematic review of the diagnostic role of
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ultrasonography in maxillofacial fractures. Int J Maxillofacial Surg. 2011; 40: 655-661.
2. Blessman M, et al. Validation of a new tool for ultrasound as a diagnostic modality in
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suspected midfacial fractures. Int J Oral Maxillofac Surg. 2007; 36: 501-506.
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3. Danter J, et al. Ultrasound imaging of nasal bone fractures with a 20-MHz ultrasound scanner. Klinik für Hals-, Nasen- und Ohrenheilkunde, Medizinischen Universität zu Lübeck. HNO 1996; 44: 324-328.
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4. Friedrich RE, et al. Potential of ultrasound in the diagnosis of midfacial fractures. Clin Oral Investig. 2003; 7: 226-229.
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5. Akizuki H, et al. Comparison between conventional radiography and ultrasound in the
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diagnosis of zygomatic complex fractures. Cranio-Maxillo-Fac Surg. 1990; 18: 263-266.
6. Rabiner JE, et al. Accuracy of point-of-care ultrasonography for diagnosis of elbow fractures in children. Ann Emerg Med. 2013; 61: 9-17.
7. Dussik K. The ultrasonic field as a medical tool. Am J Phys Med. 1954; 33: 5-20.
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8. Dussik KT. Measurements of articular tissue with ultrasound. Am J Phys Med. 1958; 37: 160-165.
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9. Ludwig GD, Struthers FW. Considerations underlying the use of ultrasound to detect gallstones and foreign bodies in tissue. Naval Medical Research Institute Reports, Project #004 001, Report No. 4, June 1949.
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10. Lee MH, et al. Comparison of high-resolution ultrasonography and computed
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tomography in the diagnosis of nasal fractures. J Ultrasound Med 2009; 28: 6717-6723.
11. Rowe, Williams. Maxillofacial injuries. 1994; 1: 157-284.
12. Nezafati S, et al. Comparison of ultrasonography with submentovertex films and
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computed tomography scan in the diagnosis of zygomatic arch fractures. Dentomaxillofac Radiol. 2010; 39: 11-16.
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13. Ogunmuyiwa SA, et al. The validity of ultrasonography in the diagnosis of
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zygomaticomaxillary complex fractures. I J Oral Maxillofac Surg 2012; 41: 500-505.
14. Jank S. Ultrasound versus computed tomography in the imaging of orbital floor fractures. J Oral Maxillofac Surg. 2004; 62: 150-154.
15. White, Pharoah. Textbook on Radiology. 6th ed. Elsevier: 2009; 185-187.
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Region of zygomatic complex
p Value
1.
Fronto-zygomatic region
.206
2.
Zygomatic arch
.000
3.
Infra-orbital region
.115
4.
Zygomatic buttress region
.000
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Sl. No.
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Table 1. Region imaged and statistical significance
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Fig 1: USG scan at Lt FZ region demonstrating fracture
Fig 2: Control scan unaffected Rt side of same patient
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Fig 3: PNS view of same patient demonstrating intact FZ suture regions bilaterally
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Fig 4: transvaginal probe used for imaging of zygomatic buttress
Fig 5: Placement of USG probe at zygomatic arch area