J
Oral Maxlllofac
49:1023-1025.
Surg
1991
A Method to Accurately Determine the Preinjury In tercan thal Distance WICHIT THARANON,
DDS,* AND EDWARD ELLIS Ill, DDS, MSt
Traumatic telecanthus, or a widening of the intercanthal distance (ICD), often accompanies injuries to the naso-orbital-ethmoid (NOE) region. A number of articles have appeared in the literature that have discussed or reported surgical techniques for the correction of traumatic telecanthus. ‘-” However, most of these articles employed normative values for the ICD as guides for surgical management. It is generally stated that the ICD should be approximately half of the interpupillary distance. However, because of the difference in facial features among individuals of different age, sex and race, the ICD varies considerably for each group, and from one individual to the next. The normal range for the ICD in whites has been stated to be 33 to 34 mm in males and 32 to 33 mm in females.1° Unfortunately, the ICD in adult blacks is unavailable but is assumed to be greater than the ICD in whites. Juberg et al measured the ICD of 5- to 1l-year-old black boys and girls and found that the average values were significantly greater than those reported for whites of comparable ages.” AdditionalIy, Laestadius et al studied growth of the ICD from the newborn to the adult in whites and found that 78% of the adult ICD has been attained by 1 year of age.” Hansman studied growth of the interorbital dimension by measuring the narrowest distance between the medial orbital rims on Water’s radiographs from 1 to 25 years of age.14 The results showed that the interorbital distance, and presumably the ICD.lS increases until age 13 in females and
age 21 in males. Therefore, normal values of the ICD for adults cannot apply to teenagers or children who sustained traumatic telecanthus. Unfortunately, there are no reports describing a method to accurately determine the preinjury ICD in a given individual. A knowledge of the preinjury ICD in a trauma patient is important if one is to achieve the best result following repair of traumatic telecanthus. Normative values of the ICD cannot apply to everyone because differences in age, sex, race, and individuals occur. The purpose of this article is to present a method we have found useful in accurately determining the preinjury ICD. Technique A recent preinjury frontal photograph of the patient is requested from patient’s family or friends. The selected picture should be as large as possible and of good quality so that the ICD is clearly visible. Further, there must be something in the picture that can be measured directly in both the photograph and on the patient in the posttraumatic period (reference object). For instance, a smiling photograph of the patient with tooth exposure allows the measurement of one or more incisor teeth in the photograph. If the patient did not lose these teeth during the injury, these teeth can be measured clinically at bedside. Other anatomical structures that can be measured are the height of the auricle and the length of the eyebrow. Nonanatomical structures that are measurable in photographs are also useful, and may include earrings, stick pins, shirt collars, etc, which the patient’s relatives/friends can bring in for direct measurements. The selected picture is greatly enlarged by either photocopy or photographic reproduction. Enlargement to at least 8 X 10 in permits more accurate measurement of the photographic structures. Using vernier calipers, the ICD and the other reference structure are measured from the photographic enlargement to the nearest 0.1 mm (Fig 1).
Received from the Division of Oral and Maxillofacial Surgery, University of Texas Southwestern Medical Center. Dallas. * Resident. t Associate Professor. Address correspondence and reprint requests to Dr Ellis: Division of Oral and Maxillofacial Surgery, University of Texas Southwestern Medical Center. 5323 Harry Hines Blvd. Dallas, TX 75235403 1.
0 1991 American geons
Association
of Oral and Maxillofacial
Sur-
0278-2391/91/4909-0020$3.00/0
1023
METHOD TO DETERMINE PREINJURY INTERCANTHAL DISTANCE
1024
5
FIGURE 1. Preinjury photograph used to obtain a measure of the ICD and a reference object. These measures are used as described in the text to determine the preinjury ICD.
Using a simple ratio, the preinjury ICD is calculated by using the following formula: ZCD(actual)
=
ZCD(photo)
x Rej’Obj(actual)
RefObj(photo)
With this technique, one can determine the preinjury ICD in individuals who exhibit traumatic telecanthus. Further, it can be used to rule out traumatic telecanthus in individuals who have greater than average ICDs prior to trauma. Report of Cases
16
FIGURE 2. A. Measurement of the ICD immediately postinjury. Note that the patient has an ICD of 37 mm and it was thought that the patient may have NOE fracture. However, using the technique described in the text, if was found that the patient’s preinjury ICD was actually 37 mm. B. Measurement of the ICD several weeks following surgery. The distance is still 37 mm.
but minimal displacement of the NOE complex. Because we could not account for the 37-mm intercanthal distance from our clinical and radiologic examination, a preinjury photograph of the patient was requested from the family. When the technique described was used, it was found that the patient had a preexistent ICD of around 37 mm. The wide ICD was confirmed by the patient’s mother. During the surgery, surgical exploration of the area through the coronal incision showed that the nasal bones were separated from the frontal bone, and they were reduced and fixed. However, deeper dissection into the medial orbits was unnecessary based on our preoperative determination of his correct ICD.
Case 1 A IPyear-old white man who sustained multiple facial fractures in a motor vehicle accident was evaluated. Clinical examination revealed a Le Fort II maxillary fracture, bilateral zygomatic complex fractures, and suspected traumatic telecanthus and NOE fracture. His intercanthal distance was measured at 37 mm (Fig 2). However, palpation revealed no comminution or displacement of the nasal pyramid and the lid-traction test showed no obvious disruption of the ICD. Coronal and axial computed tomography (CT) scans revealed the fractures listed above
Case 2 A 27-year-old white man sustained multiple facial fractures in a motor vehicle accident. Clinical examination revealed Le Fort II fracture with sagittally-split palate, a laceration through the upper lip and left nose extending onto the nasal dorsum. and a NOE fracture with right traumatic telecanthus. His ICD measured 39 mm in the emergency room (Fig 3). Coronal and axial CT scans revealed, in addition to the above, gross displacement of
THARANON
1025
AND ELLIS
During the surgery, the right medial canthal tendon was found to be only partially attached to the displaced bone,
and, therefore, a right medial canthopexy was completed after restoration of bony architecture. During the surgery, an ICD of 33 mm was obtained. Two months after surgery, his ICD was 33 mm (Fig 3B).
References I. Callahan A. Callahan MA: Fixation of the medial canthal 2. 3. 4. 5. 6.
7.
8.
9.
10. FIGURE 3. A, Measurement of the ICD immediately postinjury (39 mm). The patient appeared to have right unilateral traumatic telecanthus. B. Measurement of the intercanthal dislance 2 months postsurgery. The ICD is now 33 mm, which was determined to be the patient’s preinjury measurement from the technique described in the text.
the right nasal bone, the right frontal process of the maxilla, and the right medial orbital wall. A preinjury photograph was obtained from the patient’s family and his preinjury ICD was determined to be approximately 33 mm.
11. I?.
13. 14.
15.
structures: Evolution of the best method. Ann Plast Surg 11:242, 1983 Zide BM. McCarthy JG: The medial canthus revisited-An anatomical basis for canthopexy. Ann Plast Surg 2: 1, 1983 Rodriquer RL. Zide BM: Reconstruction of the medial canthus. Clin Plast Surg lS:255, 1988 Mustard6 JC: Epicanthus and telecanthus. Br J Plast Surg 16:346. 1963 Stoane MF: Primary treatment of naso-ethmoid injuries with increased intercanthal distance. Br J Plast Surg 23:8. 1970 Epker BN: Open surgical management of naso-orbital ethomoid facial fractures. Trans IV lntl Conf Oral Surg. Munksgaard. Copenhagen, 1973, pp 323-329 Heine RD. Catone GA. Bavitz JB, et al: Naso-orbital ethmoid injury: Report of a case and review of the literature. Oral Surg 69:542. 1990 McCarthy JG. Jelks GW. Valauri AJ: The orbit and zygoma. in McCarthy JG (ed): Plastic Surgery, vol 2. Philadelphia, PA, Saunders, 1990. pp 1610-1616 Natvig P, Dortzbach RK: Facial bone fractures, in Grabb WC. Smith JW feds): Plastic Surgery fed 2). Boston, MA. Little. Brown. 1979, pp 288-290 Recaro BC. Erickson MF: Naso-orbital ethomoidal fractures. Oral Maxillofac Clin North Am 2: 145. 1990 Pdskert JP, Manson PN, Iliff NT: Nasoethmoidal and orbital fractures. Clin Plast Surg 15:216. 1988 Juberg RC. Shotte RG, Touchstone WJ: Normal values for intercanthal distances of 5 to I I year old American blacks. Pediatrics 55:43 I. 1975 Laestadius ND, Aase JM. Smith DW: Normal inner canthal and outer orbital dimensions. J Pediatrics 74:465, 1969 Hansman CF: Growth of interorbital distance and skull thickness as observed in roentgenographic measurements. Radio1 86:87, 1966 Freihofer HM: Inner intercanthal and interorbital distances. J Maxillofac Sug X:324, 1980
Oral Maxlllofac
49:1023-1025.
Surg
1991
A Method to Accurately Determine the Preinjury In tercan thal Distance WICHIT THARANON,
DDS,* AND EDWARD ELLIS Ill, DDS, MSt
Traumatic telecanthus, or a widening of the intercanthal distance (ICD), often accompanies injuries to the naso-orbital-ethmoid (NOE) region. A number of articles have appeared in the literature that have discussed or reported surgical techniques for the correction of traumatic telecanthus. ‘-” However, most of these articles employed normative values for the ICD as guides for surgical management. It is generally stated that the ICD should be approximately half of the interpupillary distance. However, because of the difference in facial features among individuals of different age, sex and race, the ICD varies considerably for each group, and from one individual to the next. The normal range for the ICD in whites has been stated to be 33 to 34 mm in males and 32 to 33 mm in females.1° Unfortunately, the ICD in adult blacks is unavailable but is assumed to be greater than the ICD in whites. Juberg et al measured the ICD of 5- to 1l-year-old black boys and girls and found that the average values were significantly greater than those reported for whites of comparable ages.” AdditionalIy, Laestadius et al studied growth of the ICD from the newborn to the adult in whites and found that 78% of the adult ICD has been attained by 1 year of age.” Hansman studied growth of the interorbital dimension by measuring the narrowest distance between the medial orbital rims on Water’s radiographs from 1 to 25 years of age.14 The results showed that the interorbital distance, and presumably the ICD.lS increases until age 13 in females and
age 21 in males. Therefore, normal values of the ICD for adults cannot apply to teenagers or children who sustained traumatic telecanthus. Unfortunately, there are no reports describing a method to accurately determine the preinjury ICD in a given individual. A knowledge of the preinjury ICD in a trauma patient is important if one is to achieve the best result following repair of traumatic telecanthus. Normative values of the ICD cannot apply to everyone because differences in age, sex, race, and individuals occur. The purpose of this article is to present a method we have found useful in accurately determining the preinjury ICD. Technique A recent preinjury frontal photograph of the patient is requested from patient’s family or friends. The selected picture should be as large as possible and of good quality so that the ICD is clearly visible. Further, there must be something in the picture that can be measured directly in both the photograph and on the patient in the posttraumatic period (reference object). For instance, a smiling photograph of the patient with tooth exposure allows the measurement of one or more incisor teeth in the photograph. If the patient did not lose these teeth during the injury, these teeth can be measured clinically at bedside. Other anatomical structures that can be measured are the height of the auricle and the length of the eyebrow. Nonanatomical structures that are measurable in photographs are also useful, and may include earrings, stick pins, shirt collars, etc, which the patient’s relatives/friends can bring in for direct measurements. The selected picture is greatly enlarged by either photocopy or photographic reproduction. Enlargement to at least 8 X 10 in permits more accurate measurement of the photographic structures. Using vernier calipers, the ICD and the other reference structure are measured from the photographic enlargement to the nearest 0.1 mm (Fig 1).
Received from the Division of Oral and Maxillofacial Surgery, University of Texas Southwestern Medical Center. Dallas. * Resident. t Associate Professor. Address correspondence and reprint requests to Dr Ellis: Division of Oral and Maxillofacial Surgery, University of Texas Southwestern Medical Center. 5323 Harry Hines Blvd. Dallas, TX 75235403 1.
0 1991 American geons
Association
of Oral and Maxillofacial
Sur-
0278-2391/91/4909-0020$3.00/0
1023
METHOD TO DETERMINE PREINJURY INTERCANTHAL DISTANCE
1024
5
FIGURE 1. Preinjury photograph used to obtain a measure of the ICD and a reference object. These measures are used as described in the text to determine the preinjury ICD.
Using a simple ratio, the preinjury ICD is calculated by using the following formula: ZCD(actual)
=
ZCD(photo)
x Rej’Obj(actual)
RefObj(photo)
With this technique, one can determine the preinjury ICD in individuals who exhibit traumatic telecanthus. Further, it can be used to rule out traumatic telecanthus in individuals who have greater than average ICDs prior to trauma. Report of Cases
16
FIGURE 2. A. Measurement of the ICD immediately postinjury. Note that the patient has an ICD of 37 mm and it was thought that the patient may have NOE fracture. However, using the technique described in the text, if was found that the patient’s preinjury ICD was actually 37 mm. B. Measurement of the ICD several weeks following surgery. The distance is still 37 mm.
but minimal displacement of the NOE complex. Because we could not account for the 37-mm intercanthal distance from our clinical and radiologic examination, a preinjury photograph of the patient was requested from the family. When the technique described was used, it was found that the patient had a preexistent ICD of around 37 mm. The wide ICD was confirmed by the patient’s mother. During the surgery, surgical exploration of the area through the coronal incision showed that the nasal bones were separated from the frontal bone, and they were reduced and fixed. However, deeper dissection into the medial orbits was unnecessary based on our preoperative determination of his correct ICD.
Case 1 A IPyear-old white man who sustained multiple facial fractures in a motor vehicle accident was evaluated. Clinical examination revealed a Le Fort II maxillary fracture, bilateral zygomatic complex fractures, and suspected traumatic telecanthus and NOE fracture. His intercanthal distance was measured at 37 mm (Fig 2). However, palpation revealed no comminution or displacement of the nasal pyramid and the lid-traction test showed no obvious disruption of the ICD. Coronal and axial computed tomography (CT) scans revealed the fractures listed above
Case 2 A 27-year-old white man sustained multiple facial fractures in a motor vehicle accident. Clinical examination revealed Le Fort II fracture with sagittally-split palate, a laceration through the upper lip and left nose extending onto the nasal dorsum. and a NOE fracture with right traumatic telecanthus. His ICD measured 39 mm in the emergency room (Fig 3). Coronal and axial CT scans revealed, in addition to the above, gross displacement of
THARANON
1025
AND ELLIS
During the surgery, the right medial canthal tendon was found to be only partially attached to the displaced bone,
and, therefore, a right medial canthopexy was completed after restoration of bony architecture. During the surgery, an ICD of 33 mm was obtained. Two months after surgery, his ICD was 33 mm (Fig 3B).
References I. Callahan A. Callahan MA: Fixation of the medial canthal 2. 3. 4. 5. 6.
7.
8.
9.
10. FIGURE 3. A, Measurement of the ICD immediately postinjury (39 mm). The patient appeared to have right unilateral traumatic telecanthus. B. Measurement of the intercanthal dislance 2 months postsurgery. The ICD is now 33 mm, which was determined to be the patient’s preinjury measurement from the technique described in the text.
the right nasal bone, the right frontal process of the maxilla, and the right medial orbital wall. A preinjury photograph was obtained from the patient’s family and his preinjury ICD was determined to be approximately 33 mm.
11. I?.
13. 14.
15.
structures: Evolution of the best method. Ann Plast Surg 11:242, 1983 Zide BM. McCarthy JG: The medial canthus revisited-An anatomical basis for canthopexy. Ann Plast Surg 2: 1, 1983 Rodriquer RL. Zide BM: Reconstruction of the medial canthus. Clin Plast Surg lS:255, 1988 Mustard6 JC: Epicanthus and telecanthus. Br J Plast Surg 16:346. 1963 Stoane MF: Primary treatment of naso-ethmoid injuries with increased intercanthal distance. Br J Plast Surg 23:8. 1970 Epker BN: Open surgical management of naso-orbital ethomoid facial fractures. Trans IV lntl Conf Oral Surg. Munksgaard. Copenhagen, 1973, pp 323-329 Heine RD. Catone GA. Bavitz JB, et al: Naso-orbital ethmoid injury: Report of a case and review of the literature. Oral Surg 69:542. 1990 McCarthy JG. Jelks GW. Valauri AJ: The orbit and zygoma. in McCarthy JG (ed): Plastic Surgery, vol 2. Philadelphia, PA, Saunders, 1990. pp 1610-1616 Natvig P, Dortzbach RK: Facial bone fractures, in Grabb WC. Smith JW feds): Plastic Surgery fed 2). Boston, MA. Little. Brown. 1979, pp 288-290 Recaro BC. Erickson MF: Naso-orbital ethomoidal fractures. Oral Maxillofac Clin North Am 2: 145. 1990 Pdskert JP, Manson PN, Iliff NT: Nasoethmoidal and orbital fractures. Clin Plast Surg 15:216. 1988 Juberg RC. Shotte RG, Touchstone WJ: Normal values for intercanthal distances of 5 to I I year old American blacks. Pediatrics 55:43 I. 1975 Laestadius ND, Aase JM. Smith DW: Normal inner canthal and outer orbital dimensions. J Pediatrics 74:465, 1969 Hansman CF: Growth of interorbital distance and skull thickness as observed in roentgenographic measurements. Radio1 86:87, 1966 Freihofer HM: Inner intercanthal and interorbital distances. J Maxillofac Sug X:324, 1980
