Учебники / Color atlas of temporomandibular joint surgery Quinn

FIG. 8 . 2

A B

A, B An 1 1-year-old girl displaying deviation of the mandible on terminal opening. This asymmetry is secondary to a compressive growth disturbance in the right condyle-ramus region secondary to neurofibromatosis. C, Three-dimensional CT scan showing marked distortion of ramus in the coronoid notch area. D, Soft tissue mass on axial CT scan showing lesion depicted in C. Biopsy proved the lesion to be neurofibromatosis.

FIG. 8 . 4

A B

A, Coronol CT scan showing well-defined lytic lesion at posterior edge of the mylohyoid ridge. Biopsy proved the lesion to be neurofibromatosis. B, C, Inlraoral ramal approach for excision of neurofibromatosis.

Another benign lesion that requires surgical intervention is synovial chondromatosis. Synovial chondromatosis is a cartilaginous metaplasia that results in the proliferation of abnormal synovia. The hypertrophied synovial tissue produces multiple foci of hyaline cartilage. These cartilaginous nodules can eventually become detached from the synovial membrane and produce loose bodies in the joint. These have been referred to in the past as "joint mice." Patients with this condition usually show signs of a space-occupying lesion that causes preauricular swelling, pain, decreased range of motion, and malocclusion. Pressure resorption from collections of these loose cartilaginous bodies can cause perforation of the middle cranial fossa, with leaking of cerebral spinal fluid and resorption of the condyle. Computer tomographic scans and magnetic resonance imaging are extremely helpful in identifying loose bodies in the joint space. The cartilaginous nodules arc radiopaque only if they are sufficiently calcified at the time of the imaging study. The metaplastic synovial can initially be visualized and biopsied by arthroscopy. Once the diagnosis of synovial chondromatosis is made, the treatment is open arthroplasty for removal of the loose bodies and a synovectomy. Although complete removal of all the synovial membrane is extremely difficult, attempts should be made to excise the hypertrophied synovial tissue wherever possible. A meniscectomy may be necessary to gain access to the metaplastic tissue in advanced cases. In joints where only several loose bodies are identified and the synovial tissue appears to be grossly normal, the loose bodies may be composed of dead cancellous bone and fibril la ted cartilage. These characteristics are consistent with osteochondrosis dissecans. This condition does not require an extensive synovectomy, and removal of the loose body (or bodies) alone should be sufficient.

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FIG. 8 . 5

A B

A, Arthroscopic cannula in place with spontaneous egress of hundreds of small, loose cartilaginous bodies.

B, Specimen of loose cartilaginous bodies ("joint mice").

FIG. 8 . 6

A B

A, A variant of synovial chondromatosis in which a single collection of fused cartilaginous body was displacing the condyle from the right fossa and causing decreased range of motion, pain, and posterior ipsilateral open bite. B, Surgical specimen of condensed mass of synovial chondromatosis.

B

A

D

c

A, Coronal CT scan showing gross displacement of the condyle from the left fossa. B, Erosion through the roof of the glenoid fossa into the middle cranial fossa. C, Surgical specimen being removed. D, Specimen on biopsy was read as synovial chondromatosis.

FIG. 8 . 8

A B

A, B, A 5-year-old girl exhibiting progressive ankylosis and asymmetry. C, CT scan showing soft tissue mass eroding the medial surface of the mandible on the right side. D, Postsurgical lateral view of the patient showing position of the inferior mandibular incision used to excise the aggressive fibromatosis lesion on the medial surface of the mandible.

FIG. 8 . 9

A B

E

A, B, A 26-year-old woman who had undergone five previous surgical procedures (with sacrifice of the right facial nerve) for excision of "recurrent tumor" of parotid. Biopsy proved the lesion to be aggressive fibromatosis. The axial CT scans in C and D show the two distinct lesions causing bone destruction: one is at the base of the sigmoid notch and the other at the posterior and inferior border of the mandible.

E, Panorex x-ray film showing a large lytic lesion of the posterior-inferior angle of the mandible with a smaller radiolucenl lesion at the junction of the coronoid notch and coronoid process.

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