- Email: [email protected]
Magnetic resonance imaging of temporomandibular joint after surgical treatment of internal derangement
Magnetic resonance imaging of temporomandibular joint after surgical treatment of internal derangement Per-Lennart Westesson, DDS, PhD,np b Je$rey M. Cohen, DMD,b and Ross H. Tallents, DDS,b Rochester, N.Y. UNIVERSITY OF ROCHESTER SCHOOL OF MEDICINE AND DENTISTRY, AND EASTMAN DENTAL CENTER Sagittal and coronal surface coil magnetic resonance imaging was performed on 21 patients who about 2 years earlier had surgery for temporomandibular joint internal derangement. Surgical procedure included disk repositioning (23 joints) and diskectomy (seven joints). At the time of reimaging, 20 joints showed recurrence of pain and 10 joints were asymptomatic. Extensive fibrous tissue was seen in the joint space and in the joint capsule in 13 of the 20 painful joints, whereas minimal fibrous tissue in the lateral capsule wall was seen in 3 of the 10 nonpainful joints. Fibrous tissue was surgically confirmed in 10 of the painful joints. Disk displacement was seen in 11 of the 23 joints that had surgical disk repositioning. Disk displacement was seen in both painful (Q/l 7) and nonpainful joints (2/6). It was concluded that magnetic resonance imaging is an excellent method for postoperative imaging of the temporomandibular joint and that attention should be directed to the presence or absence and extension of the fibrous tissue in the joint space and in the joint capsule. (ORAL SURG ORAL MED ORAL PATHOL 1991;71:407-11)
I
nternal derangement and degenerativejoint disease are the most common disorders affecting the temporomandibular joint (TMJ).‘v2 The most common form of internal derangement is displacement of the disk interfering with the smooth function of the joint. The internal derangement is generally treated with nonsurgical methods, but for 1% to 17% of the patients surgical treatment might be indicated.3-5The most common surgical treatment methods are disk repositioning3 and diskectomy.5,9 Surgical treatment is generally successful, and a successrate of approximately 90% has been reported for both disk repositioning3 and diskectomy.819 However, in a few cases pain and dysfunction are not eliminated with surgery or recur sometime after surgery. These patients present a clinical problem, and a thorough diagnostic reevaluation is required.
In previous investigations the intra-articular anatomy of patients with failed surgical treatment have been studied with arthrography.lO, l’ However, arthrography is limited to the detection of intra-articular changes and alterations in the joint capsule and surrounding tissues would not be seen. With the introduction of magnetic resonance imaging (MRI) with surface coils,12-15we have a powerful tool for studying both the soft and hard tissuesof the joint and its surrounding region. The potential of MRI for postsurgical imaging of the TMJ was documented in a recent study on failed TMJ prostheses.r6 We also believe that MRI is a valuable tool for imaging after disk surgery. The purpose of this report is to describe our early experience with MRI in asymptomatic and symptomatic joints of patients who have previously undergone surgery for internal derangement. PATIENTS
Supported by the Torsten and Ragnar Saderberg Foundation, Stockholm, Sweden. aDepartments of Radiology and Clinical Dentistry, University of Rochester School of Medicine and Dentistry. bDepartment of Orthodontics, Eastman Dental Center. 7/12/26012
AND METHODS
The study was basedon 30 joints operated on in 21 patients (20 females, 1 male) who were seenfor MRI after surgical disk repositioning (23 joints) or diskectomy (7). The average age was 3 1 years, with a range from 15 to 53 years. Presurgical imaging was per407
408
Westesson,Cohen, and Tallents
Fig. 1. Sagittal MRI before (A) and 12 months after (B) diskectomy. Patient was asymptomatic at time of follow-up imaging. A, Before surgery, disk was anteriorly displaced (large black arrows). B, At follow-up, disk is not seen. Tissue (white arrows) between condyle (C) and glenoid fossa has intermediate signal similar to that before surgery. This is compatible with articular cartilage. There is no evidence of fibrous tissue in joint space. (Courtesy of Dr. L.-G. Hansson.)
formed in all joints, with arthrography (19 joints), MRI (7), or computed tomography (CT) (4) and showeddifferent stagesof internal derangement in all surgically treated joints. Imaging after surgery was done if symptoms recurred in the treated joint or if symptoms occurred in the contralateral joint. The average time between surgery and reimaging was 2.4 years, with a range of
1 month to 6 years. Twenty joints were reimaged becauseof pain, and 10joints were reimaged becauseof pain in the contralateral joint. MRI was performed with a 1.5 T magnetic resonance unit (Signa, General Electric Co., Milwaukee, Wise.) with the head coil as transmitter and dual surface coils (8 X 6 cm) as receivers. By this arrangement both left and right joints were imaged at the same time.“, ‘s Images were obtained at the closed and open mouth positions in the sagittal plane and at the closed mouth position in the coronal plane. During the period of time that this material was collected, several different pulse sequenceswere employed, but toward the end of the study we consistently used TR = 2200 milliseconds and TE = 20/80 milliseconds for the closed mouth position images in the sagittal and coronal planes, and TR = 1000 and TE = 20 milliseconds for the open mouth position. We used 3 mm thick contiguous slices that were oriented perpendicular (sagittal images) or parallel (coronal images) to the long axis of the condyle.19For the open mouth position, a disposablesyringe wrapped in gauze was placed between the upper and lower teeth to stabilize the mandibular position. We used a matrix of 192 X 256 and half excitation for the closed mouth images and one excitation for the open mouth images. This resulted in a scanning time of 4 minutes 17 secondsfor the closed mouth sagittal and coronal images,and 2 minutes 21 secondsfor the sagittal open mouth views. An initial localizer (TR = 400 milliseconds, TE = 20 milliseconds) was used for prescribing the sagittal and coronal images. All images were interpreted by one of the authors (P.L.W.). The position and function of the disk in the postsurgical images was interpreted according to previously described criteria’2-‘4, 2o,2’ as normal superior or as disk displacement with or without reduction. Fibrous tissue in the joint capsule and/or in the joint spacewas noted when an area of low signal intensity was seen in these regions. RESULTS
MRI before and 1 year after diskectomy of a joint is shown in Fig. 1. This joint was asymptomatic at the time of imaging. In the presurgical image (Fig. 1, A) the disk is located anterior to the condyle, and after surgery (Fig. 1, B) the disk is not seen. The tissue in the joint space between the condyle and the glenoid fossa is of intermediate signal intensity compatible with the appearanceof posterior disk attachment and fibrocartilage on the articular surfaces of the condyle and in the glenoid fossa.This represents a characteristic image of a nonpainful joint after diskectomy. In the painful joints imaged after diskectomy were different amounts of tissue of low signal intensity in-
Volume7I Number 4
MRI of TMJ after treatment of internal derangement 409
Fig. 3. Sagittal MRI obtained 2.6 years after diskectomy in patient with recurrence of pain. Extensive fibrous tissue (nrrows) fills entire joint area, suggesting fibrous ankylosis.
DISCUSSION
Fig. 2. MRI of lateral (A) and medial (B) parts of painful joint 3.7 years after surgical disk repositioning. Fibrous tissue with low signal intensity is in joint space (A, arrows) and also in medial capsule wall (B, arrows).
terpreted as fibrous tissue in the joint spaceand/or in the joint capsule (Figs. 2 and 3). In the patient shown in Fig. 2 fibrous tissue is in the joint space(Fig. 2, A) as well as in the medial capsule wall (Fig. 2, B). In the patient shown in Fig. 3, extensive fibrous tissue is between the condyle and glenoid fossa,filling up the entire area of the joint. This extensive amount of fibrous tissue was seenonly in the painful postoperative joints and was noted in 13 of the 20 painful joints (4 after diskectomy and 9 after disk repositioning). The presence of fibrous tissue was surgically confirmed in 10 joints. Small amounts of fibrous tissue in the lateral capsule wall (Fig. 4) was seenin three of the nonpainful joints. The tissue of low signal intensity in the nonpainful joints was confined to the lateral capsule wall (Fig. 4, C). Disk displacement was seen in 11 of the 23 joints treated with surgical disk repositioning (Fig. 5). Disk displacement was seen in both painful (9/17 joints) and nonpainful joints (2/6 joints).
Surgery of the TMJ is generally successfu1,3’ 8*9 and this seriesof patients representsa very small proportion of all patients surgically treated for TMJ internal derangement during this period of time. The study does not investigate the successrate of TMJ surgery, becauseit is specifically focused on findings in postsurgical MRI. The findings of this study do not indicate that a single morphologic alteration seen in postoperative MRI scans was consistently associated with recurrence of symptoms after surgery for internal derangements. The observation of extensive fibrous tissue in the joint spaceand in the joint capsule in 13 of the 20 painful joints suggeststhat this fibrous tissue might be one morphologic reason for the postoperative symptoms. Surgically, this fibrous tissue represented different degrees of fibrous ankylosis. There are also other reasons for recurrence of symptoms after surgery, one of which might be a recurrence of disk displacement. However, there is no clear-cut relationship between recurrence of symptoms and disk displacement because displacement was seen in both symptomatic and asymptomatic joints. It appears from the observations in this study and also from experience with arthroscopy that symptom relief can occur despite the disks being anteriorly displaced.22The significance of the position of the disk in postsurgical casesis not fully understood at this time. Studies of asymptomatic volunteers have shown different forms of disk displacement in 15% of the examined population.23 On the basis of our clinical experience and findings of this study, it appears that MRI is the method of choice for imaging after disk surgery. Alternative
410
Westesson,Cohen, and Tallents
ORAl
SI’RG
OR;%1
Mm
0R4l.
PAltiOI. Amil
Fig. 4. Sagittal closed (A), open (B), and coronal (C) MRl obtained 2 years after disk repositioning. Joint was asymptomatic at time of follow-up imaging. Disk (A and B, arrows) is located superior to condyle and functions normally on opening. C, In coronal image, lateral capsule wall is thickened (black arrows) and is compatible with scar tissue in lateral capsule wall. C. Condyle.
Fig. 5. Sagittal closed (A), open (B), and coronal (C) MRI obtained 4.3 years after surgical disk repositioning. Joint was asymptomatic at time of follow-up imaging. Disk (A and B, arrows) is located anteriorly at closed and open mouth positions, suggesting disk displacement without reduction. Disk is deformed. C, In coronal image there are irregularities at lateral pole of condyle (arrow). C, Condyle.
199 I
Volume 71 Number 4
MRI of TiUJ after treatment of internal derangement 411
techniques are arthrography and CT. Arthrography is technicallylo difficult and shows only the intra-articular status of the joint. 24This is a definitive limitation because the fibrotic changes associated with recurrence of symptoms frequently were located in the joint capsule, which would not have been demonstrated by arthrography. The useof ionizing radiation is another disadvantage of arthrography. MRI, on the other hand, provides a demonstration of both soft and hard tissues of the joint and surrounding areas without ionizing radiation and specific examiner skill. MRI is also advantageous becauseany plane of imaging can be employed without moving the patient. CT can be recommended specifically for instances where the osseouscomponentsof the joints are of primary concern. Arthrography can be selected in cases where it is important to detect a perforation or where the functional components of the symptoms are of most critical significance. However, for most postsurgical cases MRI is suggested as the imaging method of choice. In conclusion, this study demonstrated that MRI is an excellent method to image the TMJ postsurgically. The most important observation was that extensive fibrous tissue in the joint spaceand joint capsule was frequently associated with pain after surgery. This association was more pronounced than the association of recurrence of disk displacement. We acknowledge the following colleagues for letting us
reviewtheir patientcases: Drs. W. Bellavia, R. Bessette, F. Emmings, A. Imperato, B. Iranpour, V. Loveless, D. Macher, S. Orbach, L. Pollan, and D. Rosenthal.
REf ERENCES 1. Katzberg RW, Dolwick MR, Helms CA, Hopens T, Bales DJ, Coggs CC. Arthrotomography of the temporomandibular joint. Am J Radio1 1980;134:995-1003. 2. WestessonP-L, Bronstein SL, Liedberg JL. Internal derangement of the temporomandibular joint: morphologic description with correlation to joint function. ORAL SURG ORAL MED ORAL PATHOL 1985;59:323-31.
3. McCarty WL Jr, Farrar WB. Surgery for internal derangements of the temporomandibular joint. J Prosthet Dent 1979; 42:191-6. 4. Laskin DM. Surgery of the temporomandibular joint. In: Solberg WK, Clark GW. Temporomandibular joint problems: biologic diagnosis and treatment. Chicago: Quintessence, 1980: 111-27. 5. Eriksson L. Diagnosis and surgical treatment of internal derangement of the temporomandibular joint. Swed Dent J 1985;(suppl 25):1-49. 6. Lanz A. Discitis mandibularis. Zentralbl Chir 1909;36:28991.
7. Boman K. Temporomandibular joint arthritis and its treatment by extirpation of the disc. Acta Chir Stand 1947;95(suppl 118):1-225. 8. Eriksson L, WestessonP-L. Long-term evaluation of meniscectomy of the temporomandibular joint. J Oral Maxillofac Surg 1985;43:263-9. 9. Eriksson L, WestessonP-L. Diskectomy in the treatment of anterior disk displacement of the temporomandibular joint: a clinical and radiological one-year follow-up study. J Prosthet Dent 1986;55:106-16. 10. Bronstein SL. Post-surgical TMJ arthrography. Craniomandib Pratt 1984;2:165-71. 11. Kaplan PA, Reiskin AB, Tu HK. Temporomandibular joint arthrography following surgical treatment of internal derangemerits-Radiology 1987;163:217-20. 12. Harms SE. Wilk RM. Wolford LM. Chiles DG. Milam SB. The tempdromandibuiar joint: magnetic resonance imaging using surface coils. Radiology 1985;157:133-6. 13. Katzberg RW, Schenck J, Roberts D, et al. Magnetic resonance imaging of the temporomandibular joint meniscus. ORAL SURG ORAL MED ORAL PATHOL 1985:59:332-5.
14. Katzberg RW, BessetteRW, Tallents RH, et’al. Normal and abnormal temporomandibular joint: MR imaging with surface coil. Radiology 1986;158:183-9. 15. Roberts D, Schenck J, Joseph P, et al. Temporomandibular joint: magnetic resonance imaging. Radiology 1985;155: 829-30. 16. Kneeland BJ, Ryan DE, Carrera GF, Jesmanowicz A, Froncisz W, Hyde JS. Failed temporomandibular joint prostheses: MR imaging. Radiology 1987;165:179-81. 17. Hardy CJ, Katzberg RW, Frey RL, Szumowski J, Totterman S, Mueller OM. Switched surface coil system for bilateral MR imaging. Radiology 1988;167:835-8. 18. Shellock FG, PressmanBD. Dual surface coil MR imaging of bilateral temporomandibular joints: improvements in imaging protocol. AJNR 1989;10:595-8. 19. Musgrave MT, WestessonP-L, Tallents RH, Manzione JV, Katzberg RW. MRI of the TMJ: improved image quality by oblique scanning planes. ORAL SURG ORAL MED ORAL PATHOL (in press). 20. Westesson P-L, Katzberg RW, Tallents RH, Svensson SA, Espeland MA. Temporomandibular joint comparison of MR images with cryosectional anatomy. Radiology 1987;164:5964. 21. WestessonP-L, Katzberg RW, Tallents RH, Sanchez-Woodworth RE, SvenssonSA. CT and MRI of the temporomandibular joint: comparison with autopsy specimens. AJR Am J Roentgen011987;148:116.5-71. 22. Moses JJ, Sartoris D, Glass R, Tanaka T, Poker I. The effect of arthroscopic surgical lysis and lavage of the superior joint spcae on TMJ disc position and mobility. J Oral Maxillofac Surg 1989;47:674-8. 23. WestessonP-L, Eriksson L, Kurita K. Reliability of a negative clinical temporomandibular joint examination: prevalence of disk displacement in asymptomatic temporomandibular joints. ORAL SURG ORAL MED ORAL PATHOL 1989;68:551-4.
24. WestessonP-L, Eriksson L. Diskectomy of the temporomandibular joint: a double-contrast arthrotomographic follow-up study. ORAL SURG ORAL MED ORAL PATHOL 1985;59:435-40. Reprint requests to:
Per-Lennart Westesson,DDS Department of Radiology University of Rochester School of Medicine and Dentistry Rochester. NY 14627
I
nternal derangement and degenerativejoint disease are the most common disorders affecting the temporomandibular joint (TMJ).‘v2 The most common form of internal derangement is displacement of the disk interfering with the smooth function of the joint. The internal derangement is generally treated with nonsurgical methods, but for 1% to 17% of the patients surgical treatment might be indicated.3-5The most common surgical treatment methods are disk repositioning3 and diskectomy.5,9 Surgical treatment is generally successful, and a successrate of approximately 90% has been reported for both disk repositioning3 and diskectomy.819 However, in a few cases pain and dysfunction are not eliminated with surgery or recur sometime after surgery. These patients present a clinical problem, and a thorough diagnostic reevaluation is required.
In previous investigations the intra-articular anatomy of patients with failed surgical treatment have been studied with arthrography.lO, l’ However, arthrography is limited to the detection of intra-articular changes and alterations in the joint capsule and surrounding tissues would not be seen. With the introduction of magnetic resonance imaging (MRI) with surface coils,12-15we have a powerful tool for studying both the soft and hard tissuesof the joint and its surrounding region. The potential of MRI for postsurgical imaging of the TMJ was documented in a recent study on failed TMJ prostheses.r6 We also believe that MRI is a valuable tool for imaging after disk surgery. The purpose of this report is to describe our early experience with MRI in asymptomatic and symptomatic joints of patients who have previously undergone surgery for internal derangement. PATIENTS
Supported by the Torsten and Ragnar Saderberg Foundation, Stockholm, Sweden. aDepartments of Radiology and Clinical Dentistry, University of Rochester School of Medicine and Dentistry. bDepartment of Orthodontics, Eastman Dental Center. 7/12/26012
AND METHODS
The study was basedon 30 joints operated on in 21 patients (20 females, 1 male) who were seenfor MRI after surgical disk repositioning (23 joints) or diskectomy (7). The average age was 3 1 years, with a range from 15 to 53 years. Presurgical imaging was per407
408
Westesson,Cohen, and Tallents
Fig. 1. Sagittal MRI before (A) and 12 months after (B) diskectomy. Patient was asymptomatic at time of follow-up imaging. A, Before surgery, disk was anteriorly displaced (large black arrows). B, At follow-up, disk is not seen. Tissue (white arrows) between condyle (C) and glenoid fossa has intermediate signal similar to that before surgery. This is compatible with articular cartilage. There is no evidence of fibrous tissue in joint space. (Courtesy of Dr. L.-G. Hansson.)
formed in all joints, with arthrography (19 joints), MRI (7), or computed tomography (CT) (4) and showeddifferent stagesof internal derangement in all surgically treated joints. Imaging after surgery was done if symptoms recurred in the treated joint or if symptoms occurred in the contralateral joint. The average time between surgery and reimaging was 2.4 years, with a range of
1 month to 6 years. Twenty joints were reimaged becauseof pain, and 10joints were reimaged becauseof pain in the contralateral joint. MRI was performed with a 1.5 T magnetic resonance unit (Signa, General Electric Co., Milwaukee, Wise.) with the head coil as transmitter and dual surface coils (8 X 6 cm) as receivers. By this arrangement both left and right joints were imaged at the same time.“, ‘s Images were obtained at the closed and open mouth positions in the sagittal plane and at the closed mouth position in the coronal plane. During the period of time that this material was collected, several different pulse sequenceswere employed, but toward the end of the study we consistently used TR = 2200 milliseconds and TE = 20/80 milliseconds for the closed mouth position images in the sagittal and coronal planes, and TR = 1000 and TE = 20 milliseconds for the open mouth position. We used 3 mm thick contiguous slices that were oriented perpendicular (sagittal images) or parallel (coronal images) to the long axis of the condyle.19For the open mouth position, a disposablesyringe wrapped in gauze was placed between the upper and lower teeth to stabilize the mandibular position. We used a matrix of 192 X 256 and half excitation for the closed mouth images and one excitation for the open mouth images. This resulted in a scanning time of 4 minutes 17 secondsfor the closed mouth sagittal and coronal images,and 2 minutes 21 secondsfor the sagittal open mouth views. An initial localizer (TR = 400 milliseconds, TE = 20 milliseconds) was used for prescribing the sagittal and coronal images. All images were interpreted by one of the authors (P.L.W.). The position and function of the disk in the postsurgical images was interpreted according to previously described criteria’2-‘4, 2o,2’ as normal superior or as disk displacement with or without reduction. Fibrous tissue in the joint capsule and/or in the joint spacewas noted when an area of low signal intensity was seen in these regions. RESULTS
MRI before and 1 year after diskectomy of a joint is shown in Fig. 1. This joint was asymptomatic at the time of imaging. In the presurgical image (Fig. 1, A) the disk is located anterior to the condyle, and after surgery (Fig. 1, B) the disk is not seen. The tissue in the joint space between the condyle and the glenoid fossa is of intermediate signal intensity compatible with the appearanceof posterior disk attachment and fibrocartilage on the articular surfaces of the condyle and in the glenoid fossa.This represents a characteristic image of a nonpainful joint after diskectomy. In the painful joints imaged after diskectomy were different amounts of tissue of low signal intensity in-
Volume7I Number 4
MRI of TMJ after treatment of internal derangement 409
Fig. 3. Sagittal MRI obtained 2.6 years after diskectomy in patient with recurrence of pain. Extensive fibrous tissue (nrrows) fills entire joint area, suggesting fibrous ankylosis.
DISCUSSION
Fig. 2. MRI of lateral (A) and medial (B) parts of painful joint 3.7 years after surgical disk repositioning. Fibrous tissue with low signal intensity is in joint space (A, arrows) and also in medial capsule wall (B, arrows).
terpreted as fibrous tissue in the joint spaceand/or in the joint capsule (Figs. 2 and 3). In the patient shown in Fig. 2 fibrous tissue is in the joint space(Fig. 2, A) as well as in the medial capsule wall (Fig. 2, B). In the patient shown in Fig. 3, extensive fibrous tissue is between the condyle and glenoid fossa,filling up the entire area of the joint. This extensive amount of fibrous tissue was seenonly in the painful postoperative joints and was noted in 13 of the 20 painful joints (4 after diskectomy and 9 after disk repositioning). The presence of fibrous tissue was surgically confirmed in 10 joints. Small amounts of fibrous tissue in the lateral capsule wall (Fig. 4) was seenin three of the nonpainful joints. The tissue of low signal intensity in the nonpainful joints was confined to the lateral capsule wall (Fig. 4, C). Disk displacement was seen in 11 of the 23 joints treated with surgical disk repositioning (Fig. 5). Disk displacement was seen in both painful (9/17 joints) and nonpainful joints (2/6 joints).
Surgery of the TMJ is generally successfu1,3’ 8*9 and this seriesof patients representsa very small proportion of all patients surgically treated for TMJ internal derangement during this period of time. The study does not investigate the successrate of TMJ surgery, becauseit is specifically focused on findings in postsurgical MRI. The findings of this study do not indicate that a single morphologic alteration seen in postoperative MRI scans was consistently associated with recurrence of symptoms after surgery for internal derangements. The observation of extensive fibrous tissue in the joint spaceand in the joint capsule in 13 of the 20 painful joints suggeststhat this fibrous tissue might be one morphologic reason for the postoperative symptoms. Surgically, this fibrous tissue represented different degrees of fibrous ankylosis. There are also other reasons for recurrence of symptoms after surgery, one of which might be a recurrence of disk displacement. However, there is no clear-cut relationship between recurrence of symptoms and disk displacement because displacement was seen in both symptomatic and asymptomatic joints. It appears from the observations in this study and also from experience with arthroscopy that symptom relief can occur despite the disks being anteriorly displaced.22The significance of the position of the disk in postsurgical casesis not fully understood at this time. Studies of asymptomatic volunteers have shown different forms of disk displacement in 15% of the examined population.23 On the basis of our clinical experience and findings of this study, it appears that MRI is the method of choice for imaging after disk surgery. Alternative
410
Westesson,Cohen, and Tallents
ORAl
SI’RG
OR;%1
Mm
0R4l.
PAltiOI. Amil
Fig. 4. Sagittal closed (A), open (B), and coronal (C) MRl obtained 2 years after disk repositioning. Joint was asymptomatic at time of follow-up imaging. Disk (A and B, arrows) is located superior to condyle and functions normally on opening. C, In coronal image, lateral capsule wall is thickened (black arrows) and is compatible with scar tissue in lateral capsule wall. C. Condyle.
Fig. 5. Sagittal closed (A), open (B), and coronal (C) MRI obtained 4.3 years after surgical disk repositioning. Joint was asymptomatic at time of follow-up imaging. Disk (A and B, arrows) is located anteriorly at closed and open mouth positions, suggesting disk displacement without reduction. Disk is deformed. C, In coronal image there are irregularities at lateral pole of condyle (arrow). C, Condyle.
199 I
Volume 71 Number 4
MRI of TiUJ after treatment of internal derangement 411
techniques are arthrography and CT. Arthrography is technicallylo difficult and shows only the intra-articular status of the joint. 24This is a definitive limitation because the fibrotic changes associated with recurrence of symptoms frequently were located in the joint capsule, which would not have been demonstrated by arthrography. The useof ionizing radiation is another disadvantage of arthrography. MRI, on the other hand, provides a demonstration of both soft and hard tissues of the joint and surrounding areas without ionizing radiation and specific examiner skill. MRI is also advantageous becauseany plane of imaging can be employed without moving the patient. CT can be recommended specifically for instances where the osseouscomponentsof the joints are of primary concern. Arthrography can be selected in cases where it is important to detect a perforation or where the functional components of the symptoms are of most critical significance. However, for most postsurgical cases MRI is suggested as the imaging method of choice. In conclusion, this study demonstrated that MRI is an excellent method to image the TMJ postsurgically. The most important observation was that extensive fibrous tissue in the joint spaceand joint capsule was frequently associated with pain after surgery. This association was more pronounced than the association of recurrence of disk displacement. We acknowledge the following colleagues for letting us
reviewtheir patientcases: Drs. W. Bellavia, R. Bessette, F. Emmings, A. Imperato, B. Iranpour, V. Loveless, D. Macher, S. Orbach, L. Pollan, and D. Rosenthal.
REf ERENCES 1. Katzberg RW, Dolwick MR, Helms CA, Hopens T, Bales DJ, Coggs CC. Arthrotomography of the temporomandibular joint. Am J Radio1 1980;134:995-1003. 2. WestessonP-L, Bronstein SL, Liedberg JL. Internal derangement of the temporomandibular joint: morphologic description with correlation to joint function. ORAL SURG ORAL MED ORAL PATHOL 1985;59:323-31.
3. McCarty WL Jr, Farrar WB. Surgery for internal derangements of the temporomandibular joint. J Prosthet Dent 1979; 42:191-6. 4. Laskin DM. Surgery of the temporomandibular joint. In: Solberg WK, Clark GW. Temporomandibular joint problems: biologic diagnosis and treatment. Chicago: Quintessence, 1980: 111-27. 5. Eriksson L. Diagnosis and surgical treatment of internal derangement of the temporomandibular joint. Swed Dent J 1985;(suppl 25):1-49. 6. Lanz A. Discitis mandibularis. Zentralbl Chir 1909;36:28991.
7. Boman K. Temporomandibular joint arthritis and its treatment by extirpation of the disc. Acta Chir Stand 1947;95(suppl 118):1-225. 8. Eriksson L, WestessonP-L. Long-term evaluation of meniscectomy of the temporomandibular joint. J Oral Maxillofac Surg 1985;43:263-9. 9. Eriksson L, WestessonP-L. Diskectomy in the treatment of anterior disk displacement of the temporomandibular joint: a clinical and radiological one-year follow-up study. J Prosthet Dent 1986;55:106-16. 10. Bronstein SL. Post-surgical TMJ arthrography. Craniomandib Pratt 1984;2:165-71. 11. Kaplan PA, Reiskin AB, Tu HK. Temporomandibular joint arthrography following surgical treatment of internal derangemerits-Radiology 1987;163:217-20. 12. Harms SE. Wilk RM. Wolford LM. Chiles DG. Milam SB. The tempdromandibuiar joint: magnetic resonance imaging using surface coils. Radiology 1985;157:133-6. 13. Katzberg RW, Schenck J, Roberts D, et al. Magnetic resonance imaging of the temporomandibular joint meniscus. ORAL SURG ORAL MED ORAL PATHOL 1985:59:332-5.
14. Katzberg RW, BessetteRW, Tallents RH, et’al. Normal and abnormal temporomandibular joint: MR imaging with surface coil. Radiology 1986;158:183-9. 15. Roberts D, Schenck J, Joseph P, et al. Temporomandibular joint: magnetic resonance imaging. Radiology 1985;155: 829-30. 16. Kneeland BJ, Ryan DE, Carrera GF, Jesmanowicz A, Froncisz W, Hyde JS. Failed temporomandibular joint prostheses: MR imaging. Radiology 1987;165:179-81. 17. Hardy CJ, Katzberg RW, Frey RL, Szumowski J, Totterman S, Mueller OM. Switched surface coil system for bilateral MR imaging. Radiology 1988;167:835-8. 18. Shellock FG, PressmanBD. Dual surface coil MR imaging of bilateral temporomandibular joints: improvements in imaging protocol. AJNR 1989;10:595-8. 19. Musgrave MT, WestessonP-L, Tallents RH, Manzione JV, Katzberg RW. MRI of the TMJ: improved image quality by oblique scanning planes. ORAL SURG ORAL MED ORAL PATHOL (in press). 20. Westesson P-L, Katzberg RW, Tallents RH, Svensson SA, Espeland MA. Temporomandibular joint comparison of MR images with cryosectional anatomy. Radiology 1987;164:5964. 21. WestessonP-L, Katzberg RW, Tallents RH, Sanchez-Woodworth RE, SvenssonSA. CT and MRI of the temporomandibular joint: comparison with autopsy specimens. AJR Am J Roentgen011987;148:116.5-71. 22. Moses JJ, Sartoris D, Glass R, Tanaka T, Poker I. The effect of arthroscopic surgical lysis and lavage of the superior joint spcae on TMJ disc position and mobility. J Oral Maxillofac Surg 1989;47:674-8. 23. WestessonP-L, Eriksson L, Kurita K. Reliability of a negative clinical temporomandibular joint examination: prevalence of disk displacement in asymptomatic temporomandibular joints. ORAL SURG ORAL MED ORAL PATHOL 1989;68:551-4.
24. WestessonP-L, Eriksson L. Diskectomy of the temporomandibular joint: a double-contrast arthrotomographic follow-up study. ORAL SURG ORAL MED ORAL PATHOL 1985;59:435-40. Reprint requests to:
Per-Lennart Westesson,DDS Department of Radiology University of Rochester School of Medicine and Dentistry Rochester. NY 14627