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Myotonic dystrophy: Surgical and anesthetic considerations during orthognathic surgery
J Oral Maxillofac 41:667-671,
Surg
1963
Myotonic Dystrophy: Surgical and Anesthetic Considerations Orthogna thic Surgery JACK KAUFMAN,
during
DDS,* JOEL M. FRIEDMAN, DDS,t DONALD SADOWSKY, MPH, PHD,$ AND JOEL HARRIS, DDS$
DDS,
to be thin, with an exaggerated forward curvature (swan neck). ‘q3As the disease progresses, dysarthria and dysphagia may develop as a result of involvement of the laryngeal and pharyngeal muscles. Compromised respiratory capacity secondary to atrophy or myotonia of the diaphragm or accessory muscles may also develop.4 Cardiac abnormalities may be present as cardiomyopathy or as a conduction defect. Electrocardiographic changes are present in 90 per cent of cases in the late stages of the disease. l Other significant physical findings include: cataracts (42 per cent), frontal baldness (44 per cent)2 and testicular atrophy with concomitant sterility and impotence (70 per cent).2 Gynecomastia is an inconsistent finding. In females, ovarian deficiency occasionally develops, but is not usually severe enough to interfere with menstruation or fertility.3 Endocrine disturbances resulting in a change in glucose metabolism and diabetes mellitus are frequent. Low basal metabolism and hypothyroidism are frequently noted. A large proportion of patients with MD and their unaffected siblings have associated mental retardation and deterioration. Patients may seek a surgical solution for all or some of the following characteristics of myopathic faciesj: 1) A blank expression produced by facial muscles with poor tonus. 2) Ptosis. 3) A symmetrical hollowing of the temporal fossa produced by temporalis wasting which allows the mandible to be postured forward, resulting in a tendency towards an open bite, prognathic appearance and possible dislocation. (These acromegalic-like changes, of which mandibular prognathism is the most obvious, may be caused by endocrine changes that adversely affect the negative-feedback mechanism of the pituitary growth hormone). 4) Secondary dental malocclusion. Spacing problems, posterior crossbite and anterior open bite have all been observed.5*6 Understanding of the multisystem expression of MD in a surgical candidate prepares the surgeon and anesthesiologist for potential perioperative problems. Appropriate precautions and preparations for adequate management can thus be taken.
Myotonic dystrophy (Steinert’s disease) is a dominant hereditary disease classically described as a steadily progressive muscular disorder. Although the myotonic aspects of the disease are perhaps most readily apparent, myotonic dystrophy (MD) is in fact a multisystem disease. l Myotonic dystrophy is the most severe of the three clinical entities that collectively define the myotonic syndrome (the other two are myotonia congenita and paramyotonia). *.2 Myotonic dystrophy begins to manifest in adolescence or early adult life and is characterized by myotonia, muscular atrophy, cardiac abnormalities, endocrine dysfunction, testicular atrophy, mental deterioration, frontal baldness and cataracts. Members of a given line may manifest only one or two of these findings. Myotonia is the inability to relax a muscle normally after its contraction (usually a result of the repetitive discharge of the contractile mechanism of the muscle fiber). It is the most common physical finding and is best demonstrated in the adduction of the thumb, forearm muscles and tongue. The patient’s inability to release after shaking hands is a classic physical finding. Myotonic dystrophy may start with myotonia and may be followed by muscle atrophy and weakness. The earliest muscles to be involved are those of the face and neck and the peripheral muscles of the extremities. Slight ptosis (resulting from weakness of the levator palpebral muscles) and lack of facial expression (myopathic facies) may be present before other changes become evident. Since the sternocleidemastoid muscles are commonly atrophic, the patient’s neck may appear
Received from the Bronx Municipal Hospital Center-Albert Einstein College of Medicine, Bronx, New York. * Formerly Chief Resident, Oral Surgery. ,t Chief, Oral Surgery. $ Chairman, Department of Dentistry. 8 Assistant Clinical Professor (Orthodontics), Department of Dentistry. Address correspondence and reprint requests to Dr. Sadowsky: Bronx Municipal Hospital Center, Pelham Parkway S. and Eastchester Road, Bronx, NY 10461.
667
668
MYOTONIC
DYSTROPHY
Anesthetic Management
Surgical Management
In the anesthetic management of MD, emphasis must be placed on the cardiac and respiratory manifestations. Such a patient is likely to experience life-threatening complications arising from: I. Cardiomyopathy and conduction defects. Preoperatively, these patients should undergo cardiac evaluation that includes an EKG and, when indicated, a Holter monitor to evaluate intermittent conduction anomalies. Anesthesia may aggravate any pre-existing conduction block by increasing vagal tone or by causing transient hypoxia of the conduction system. During anesthesia there may be increased myocardial sensitivity to catecholamines and hypercarbia, which can lead to arrhythmias. Careful cardiac monitoring is therefore essential. 2. Hypoxia from inadequate ventilation. Many patients with atrophy or myotonia of the diaphragm or accessory muscles of respiration demonstrate sensitivity to the respiratory depressive effects of barbiturates and narcotics. Drug-induced central nervous system depression may cause severe hypoventilation or apnea. 3. Difficulty in ventilation resulting from sustained muscle contraction. In some patients the depolarizing muscle relaxants (e.g., succinylcholine), instead of producing flaccid paralysis, may cause persistent contraction of the diaphragm and of intercostal and laryngeal muscles, making intubation or ventilation impossible. The response to the nondepolarizing muscle relaxants is normal; however, their reversal with neostigmine may precipitate myotonia. I Morphine or meperidine is preferable to fentanyl, as the latter is known to cause muscle rigidity. Halothane may not be the anesthetic agent of choice because its tendency to cause postoperative shivering may precipitate or accentuate the myotonus. The tendency of halothane to increase myocardial sensitivity to exogenous catecholamines also increases the risk of cardiac arrhythmias. Warming the operating room may reduce the severity of myotonia by reducing patient shivering. It has been suggested that malignant hyperthermia is associated with intracellular disturbances that inhibit the relaxation of skeletal muscle. Some experts have postulated that an underlying muscular dystrophy, e.g., MD, may be present in patients susceptible to malignant hyperthermia.7 Postoperative respiratory insufficiency, obstruction, or failure is another major concern. Patients may require mechanical ventilation for extended periods after surgery. Diminished cough reflex, due to muscle weakness, predisposes these patients to atelectasis and postoperative pneumonia.
A review of the literature revealed a somewhat surprising disregard for the potential surgical hazards associated with the orthognathic management of the MD patient .8.9 The myopathic face is characteristically long, with vertical maxillary excess, increased lower facial height, lip incompetence, and a tendency towards prognathism and an anterior open bite.6l9 In normal patients, surgical correction generally involves total maxillary and mandibular osteotomies, which necessitates maxillomandibular fixation (MMF) for as long as eight weeks. With proper nutritional guidance, this is generally tolerated well by patients. In patients with MD, however, weakness of the pharyngeal musculature can lead to dysphagia, while myotonia of the tongue can cause a potentially fatal airway obstruction.6 It is obvious that postoperative edema together with MMF in such patients can severely complicate their postoperative courses. It would seem practical, therefore, to design a treatment plan that avoids the use of MMF. Depending upon the severity of the dentofacial deformity, this may involve minor compromises in postoperative facial esthetics and occlusal relationships. Treatment plans requiring extended orthodontic treatment, or the need for supplementary surgical procedures (e.g., genioplasty or proplast augmentation) may require modification. The following case illustrates the special anesthetic and surgical problems involved in the management of a patient with myotonic dystrophy. Report of a Case A 26-year-old 5’6” slender white man seeking correction for what he described as his large jaw and poor bite was referred to one of the authors (JMF) for evaluation and possible correction of his problem. Physical findings included normal posture and gait, generalized weakness of the upper extremities with atrophy of forearm musculature, bilateral temporal muscle wasting and frontoparietal hair loss. The patient had a flexed right foot and diiculty releasing a clenched fist. He reported difficulty in speech upon awakening because of a “knotting” of his tongue, which resolved shortly thereafter. He denied any difficulties in swallowing or breathing, and denied a history of cardiac problems. There was no other significant past medical history. These findings were all consistent with MD, the diagnosis of which had been made by a neurologist a year prior to the examination. The family history revealed that the patient’s paternal grandfather and father apparently had had MD, although definitive diagnoses had never been made. His older brother (and only sibling) had been diagnosed as having MD by the same neurologist shortly before his own diagnosis had been made. Maxillofacial evaluation revealed a long, trapezoidal face with a prominent square chin, large mandible, lip competence with strain and no labiomental fold (Fig. 1A). The
KAUFMAN
ET AL
patient showed 7 mm of maxillary anterior tooth at rest. The tooth-lip relationship was strongly suggestive of vertical maxillary hyperplasia. There was a full complement of maxillary and mandibular teeth, with good arch form except for anterior crowding (Fig. 1B). Anterior bite was edge-to-edge, and there was a slight lingual cant of the lower incisors. The patient functioned in an Angle Class III molar relationship. The maxillary dental midline was coincident with the facial midline, while the mandibular dental midline deviated 3 mm to the left. There was no deviation of the mandible upon opening, no pain or noise from either TMJ, and no history of subluxation. Cephalometric evaluation confirmed our clinical impression of increased lower facial height. His mandible demonstrated an excessive vertical growth pattern which is consistent with vertical maxillary excess (Fig. 10. Our goal was to reduce lower facial height, reduce chin prominence, and reduce vertical maxillary excess, and in so doing, to reduce the amount of visible maxillary anterior tooth. Presurgical orthodontic treatment using edgewise direct-bonded brackets would correct the linguoversion of the lower incisors and thereby eliminate the lower anterior crowding. The anterior edge-to-edge occlusion would then be corrected surgically, the dental midlines made coincident, and a Class I molar relationship achieved. Under ideal circumstances, we would treat this case by utilizing a LeFort I osteotomy to reduce maxillary vertical hyperplasia and a mandibular ramus procedure to retrude the mandible and thereby correct occlusal relationships and reduce mandibular length. Mandibular autorotation would correct lower facial height. This treatment plan, however, would necessitate the use of MMF. In an effort to avoid this, an alternate treatment plan was devised. A LeFort I alveolar osteotomy would still be used to reduce maxillary vertical excess and allow for mandibular autorotation. To correct the resulting anterior cross-bite, align the dental midlines, and avoid MMF, a mandibular anterior subapical osteotomy would be performed (after extraction of lower first premolars). In order to achieve a Class I molar relationship, maxillary first premolars would be extracted and the posterior segments of the maxilla would be advanced. Stabilization would be achieved with individual maxillary and mandibular occlusal splints, the maxilla being stabilized superiorly by suspension wires. The need for MMF would be avoided. With both arches in their new positions, a 5-mm wedge genioplasty would be done to further reduce lower facial height and retrude the chin point. Hospital Course. After acceptance of our treatment plan and consultation with his neurologist, the patient was admitted to the Albert Einstein College Hospital for surgery. The results of preoperative laboratory evaluation, including SMA6 and SMA12 test batteries, prothrombin time, CBC, EKG, chest radiography, and urinalysis, were within normal limits, except for a slight elevation of creatine phosphokinase to 157 mIU/ml (normal range O-145) which was considered by the anesthesiologist to be insignificant. A potentially difficult intubation was anticipated because of a prominent anteriorly positioned cricothyroid cartilage. The patient was sedated preoperatively with meperidine, hydroxyzine, and atropine. The temperature in the operating room was 80” E The patient was placed on a cooling mattress and all emergency drugs including dantrolene were available. An
669
esophageal temperature probe was used for monitoring. Anesthesia was induced with enflurane and nitrous oxide. Thiopental and muscle relaxants (depolarizing or nondepolarizing) were not used. A cardiac monitor on lead II was employed. Under deep surgical anesthesia nasotracheal intubation was achieved with difficulty. Induction was otherwise smooth, and the patient was prepared and draped in the usual manner. Lidocaine with l/100,000 epinephrine was injected into the maxillary and lower anterior mucobuccal folds for hemostasis. After extraction of the lower first premolars, a lower subapical osteotomy was performed in the routine manner and the prefabricated lower occlusal stent was wired into place. Below the osteotomy, S-mm wedge of bone was removed and the chin point repositioned superiorly and posteriorly and ligated in place with 25gauge wire. The incision was then closed with 3-O chromic suture. In the maxilla an incision was made from the second molar anteriorly to the mesial of the second premolar bilaterally. An anterior horizontal incision was also made from the distal of the left canine to the distal of the right. Periosteum was reflected to expose the labial plate of bone, from which a premeasured width was surgically removed. A total labial osteotomy from pterygoid plate to pyriform rim bilaterally was performed, thus allowing access through which the palatal osteotomy was made trans-antrally. The pterygoid plates were then cleaved with a curved osteotome and total downfracture of the dentoalveolar segment of the maxilla was accomplished. The upper first premolars were extracted and vertical osteotomies through the extraction sites divided the dento-alveolar segment into three segments. All three segments were intruded, the posterior segments were advanced, and the maxillary occlusal splint was then wired to the three maxillary segments. The mandible was then closed until the maxillary and mandibular splints keyed together. This determined the final position of the maxilla, which was then secured to the stable midface with suspension wires from the buttress and pyriform rims bilaterally. The maxillary incision was closed with 3-O chromic suture. From both a surgical and anesthetic standpoint, the patient tolerated the procedure very well. Total blood loss was 450 ml; he received 1,700 ml of lactated Ringer’s solution and dextrose intraoperatively. Cardiac arrhythmias were not seen, and there was no problem with ventilation. The temperature remained constant at 36” C throughout surgery. There were no episodes of muscle rigidity or manifestations of myotonia throughout surgery. Upon leaving the operating room, the patient was breathing spontaneously but remained intubated. In the recovery room, management included a cardiac monitor and T-tube humidifier. The patient’s condition remained stable, and the trachea was extubated two hours postoperatively, after return of laryngeal reflexes and adequate tidal volume. Beginning on the evening of the day of surgery the patient began taking fluids orally with minimal difficulty. He quickly increased his fluid intake by the second postoperative day, and the intravenous line was discontinued. He ambulated early and was able to avoid postoperative atelectasis by adhering to a regimen of coughing and deep breathing. Postoperative SMA6 tests and CBC were normal, and he remained afebrile. He was discharged to home on the fourth postoperative day. Weekly postoperative visits followed his uneventful recovery. He reported no difficulty at any time in swal-
670
FIGURE 1. Preoperative appearance. A (rap), full face and profile. B (middle), occlusion. C (bottom), lateral cephalogram.
lowing or breathing. Curiously, he noticed an improvement in early morning speech and the disappearance of the “tongue-knotting” he had been experiencing before the operation. The occlusal splints were removed in the fifth postoperative week and stabilization was maintained with orthodontic arch wire. Orthodontic adjustments were continued every four weeks. One year postoperatively (Fig.
KAUFMAN
ET AL
FIGURE 2. Postoperative appearance. A (top), full face and profile. B (middle), postorthodontic occlusion. C (bottom), lateral cephalogram. 2) the patient’s occlusion
is stable and his myopathic face has been significantly altered. The patient is very satisfied with all aspects of the surgical result.
Summary The surgical and anesthetic considerations of orthognathic surgery for a patient with myotonic dys-
671
MYOTONIC DYSTROPHY
trophy are discussed. A case report is presented demonstrating how a surgical treatment plan can be modified to avoid the potential postoperative problems associated with this disease. References 1. Dalal FY, et al: Dystrophic myotonia: a multisystem disease. Can Anaesth Sot J 19:436, 1972 2. Bhatt GP, Vijayan N, Dreyfus PM: Myotonia, a review of its clinical implications. Calif Med 114:16, 1971 3. Mudge BJ, Taylor PB, Vanderspek AFL: Perioperative hazards in myotonia dystrophy. Anesthesia 33:492, 1980
J Oral Maxillofac 41571675.
4. Casey EB, Amirioff MJ: Dystrophic myotonia presenting with dysphagia. Br Med J 22:443, 1971 5. Thayer A, Harley H, Crenshaw: Oral manifestations of myotonic muscular dystrophy. J Am Dent Assoc 72:1405,1%6 6. Wald C: Myotonia dystrophy-sedative and anesthetic management. Oral Surg 39:886, 1975 7. Kent JN, Winslow JR: Correction of severe dentofacial deformity association with myotonia congenita. J Oral Surg 36: 129, 1978 8. Kamiishi H, Ohtsuka H, Shioya N: Correction of myopathic face associated with myotonic muscular dystrophy. J Maxfat Surg 548, 1977 9. Petri WH, Stump TE: Familial dystrophic myotonia: report of a case. J Oral Surg 35:667, 1977
Surg
1983
Leiomyoma
of the Right Lower Gingiva:
A Case and a Review of the Japanese Literature HIROTSUGU
YAMAMOTO,
DDS, MINORU TAKAGI, DDS,* SHIGEO OTAKE, DDS, AND MOTOH OHMORI, DDS,t
Leiomyomas which are common benign tumors of smooth muscle, are infreauentlv encountered in the oral cavity.] There are few reports of ultrastructural studies of oral leiomyomas. We present a case of leiomyoma of the lower gingiva which was diagnosed on the basis of the ultrastructure. Twentynine cases of oral leiomyoma reported in Japan are reviewed.
Grossly, the resected tumor was 4.8 x 2.8 x 2.6 cm in size and had a solid gray cut surface with a partially fascicular structure (Fig. 2). Microscopically, the tumor was not completely encapsulated. It was composed of interlacing fascicles of spindle cells which had slightly
Report of a Case An 18-year-old Japanese girl was referred by her private dentist to our University Hospital on April 27, 1981. There was a painless mass of the lingual gingiva of the right lower second molar. It had been present for two months, but had rapidly grown during the last several days. The patient had no remarkable past history. The tumor was sessile in character and a gray color (Fig. 1). The second molar was slightly mobile to palpation. Radiographs revealed slight horizontal resorption of the alveolar bone in the right lower molar region. Resection of the tumor was performed on June 6, and there has been no recurrence since. Received from the Departments of Clinical Pathology and Oral Surgery,t Nihon University School of Dentistry, 2-870-1, Sakaecho-Nishi, Matsudo, Chiba 271, Japan. * Department of Oral Pathology, Faculty of Dentistry, Tokyo Medical and Dental Universitv. Tokvo. Jaoan. Address correspondence and rep&t requests to Dr. Yamamoto.
FIGURE 1. Clinical appearance of the tumor of the right lower lingual gingiva.
Surg
1963
Myotonic Dystrophy: Surgical and Anesthetic Considerations Orthogna thic Surgery JACK KAUFMAN,
during
DDS,* JOEL M. FRIEDMAN, DDS,t DONALD SADOWSKY, MPH, PHD,$ AND JOEL HARRIS, DDS$
DDS,
to be thin, with an exaggerated forward curvature (swan neck). ‘q3As the disease progresses, dysarthria and dysphagia may develop as a result of involvement of the laryngeal and pharyngeal muscles. Compromised respiratory capacity secondary to atrophy or myotonia of the diaphragm or accessory muscles may also develop.4 Cardiac abnormalities may be present as cardiomyopathy or as a conduction defect. Electrocardiographic changes are present in 90 per cent of cases in the late stages of the disease. l Other significant physical findings include: cataracts (42 per cent), frontal baldness (44 per cent)2 and testicular atrophy with concomitant sterility and impotence (70 per cent).2 Gynecomastia is an inconsistent finding. In females, ovarian deficiency occasionally develops, but is not usually severe enough to interfere with menstruation or fertility.3 Endocrine disturbances resulting in a change in glucose metabolism and diabetes mellitus are frequent. Low basal metabolism and hypothyroidism are frequently noted. A large proportion of patients with MD and their unaffected siblings have associated mental retardation and deterioration. Patients may seek a surgical solution for all or some of the following characteristics of myopathic faciesj: 1) A blank expression produced by facial muscles with poor tonus. 2) Ptosis. 3) A symmetrical hollowing of the temporal fossa produced by temporalis wasting which allows the mandible to be postured forward, resulting in a tendency towards an open bite, prognathic appearance and possible dislocation. (These acromegalic-like changes, of which mandibular prognathism is the most obvious, may be caused by endocrine changes that adversely affect the negative-feedback mechanism of the pituitary growth hormone). 4) Secondary dental malocclusion. Spacing problems, posterior crossbite and anterior open bite have all been observed.5*6 Understanding of the multisystem expression of MD in a surgical candidate prepares the surgeon and anesthesiologist for potential perioperative problems. Appropriate precautions and preparations for adequate management can thus be taken.
Myotonic dystrophy (Steinert’s disease) is a dominant hereditary disease classically described as a steadily progressive muscular disorder. Although the myotonic aspects of the disease are perhaps most readily apparent, myotonic dystrophy (MD) is in fact a multisystem disease. l Myotonic dystrophy is the most severe of the three clinical entities that collectively define the myotonic syndrome (the other two are myotonia congenita and paramyotonia). *.2 Myotonic dystrophy begins to manifest in adolescence or early adult life and is characterized by myotonia, muscular atrophy, cardiac abnormalities, endocrine dysfunction, testicular atrophy, mental deterioration, frontal baldness and cataracts. Members of a given line may manifest only one or two of these findings. Myotonia is the inability to relax a muscle normally after its contraction (usually a result of the repetitive discharge of the contractile mechanism of the muscle fiber). It is the most common physical finding and is best demonstrated in the adduction of the thumb, forearm muscles and tongue. The patient’s inability to release after shaking hands is a classic physical finding. Myotonic dystrophy may start with myotonia and may be followed by muscle atrophy and weakness. The earliest muscles to be involved are those of the face and neck and the peripheral muscles of the extremities. Slight ptosis (resulting from weakness of the levator palpebral muscles) and lack of facial expression (myopathic facies) may be present before other changes become evident. Since the sternocleidemastoid muscles are commonly atrophic, the patient’s neck may appear
Received from the Bronx Municipal Hospital Center-Albert Einstein College of Medicine, Bronx, New York. * Formerly Chief Resident, Oral Surgery. ,t Chief, Oral Surgery. $ Chairman, Department of Dentistry. 8 Assistant Clinical Professor (Orthodontics), Department of Dentistry. Address correspondence and reprint requests to Dr. Sadowsky: Bronx Municipal Hospital Center, Pelham Parkway S. and Eastchester Road, Bronx, NY 10461.
667
668
MYOTONIC
DYSTROPHY
Anesthetic Management
Surgical Management
In the anesthetic management of MD, emphasis must be placed on the cardiac and respiratory manifestations. Such a patient is likely to experience life-threatening complications arising from: I. Cardiomyopathy and conduction defects. Preoperatively, these patients should undergo cardiac evaluation that includes an EKG and, when indicated, a Holter monitor to evaluate intermittent conduction anomalies. Anesthesia may aggravate any pre-existing conduction block by increasing vagal tone or by causing transient hypoxia of the conduction system. During anesthesia there may be increased myocardial sensitivity to catecholamines and hypercarbia, which can lead to arrhythmias. Careful cardiac monitoring is therefore essential. 2. Hypoxia from inadequate ventilation. Many patients with atrophy or myotonia of the diaphragm or accessory muscles of respiration demonstrate sensitivity to the respiratory depressive effects of barbiturates and narcotics. Drug-induced central nervous system depression may cause severe hypoventilation or apnea. 3. Difficulty in ventilation resulting from sustained muscle contraction. In some patients the depolarizing muscle relaxants (e.g., succinylcholine), instead of producing flaccid paralysis, may cause persistent contraction of the diaphragm and of intercostal and laryngeal muscles, making intubation or ventilation impossible. The response to the nondepolarizing muscle relaxants is normal; however, their reversal with neostigmine may precipitate myotonia. I Morphine or meperidine is preferable to fentanyl, as the latter is known to cause muscle rigidity. Halothane may not be the anesthetic agent of choice because its tendency to cause postoperative shivering may precipitate or accentuate the myotonus. The tendency of halothane to increase myocardial sensitivity to exogenous catecholamines also increases the risk of cardiac arrhythmias. Warming the operating room may reduce the severity of myotonia by reducing patient shivering. It has been suggested that malignant hyperthermia is associated with intracellular disturbances that inhibit the relaxation of skeletal muscle. Some experts have postulated that an underlying muscular dystrophy, e.g., MD, may be present in patients susceptible to malignant hyperthermia.7 Postoperative respiratory insufficiency, obstruction, or failure is another major concern. Patients may require mechanical ventilation for extended periods after surgery. Diminished cough reflex, due to muscle weakness, predisposes these patients to atelectasis and postoperative pneumonia.
A review of the literature revealed a somewhat surprising disregard for the potential surgical hazards associated with the orthognathic management of the MD patient .8.9 The myopathic face is characteristically long, with vertical maxillary excess, increased lower facial height, lip incompetence, and a tendency towards prognathism and an anterior open bite.6l9 In normal patients, surgical correction generally involves total maxillary and mandibular osteotomies, which necessitates maxillomandibular fixation (MMF) for as long as eight weeks. With proper nutritional guidance, this is generally tolerated well by patients. In patients with MD, however, weakness of the pharyngeal musculature can lead to dysphagia, while myotonia of the tongue can cause a potentially fatal airway obstruction.6 It is obvious that postoperative edema together with MMF in such patients can severely complicate their postoperative courses. It would seem practical, therefore, to design a treatment plan that avoids the use of MMF. Depending upon the severity of the dentofacial deformity, this may involve minor compromises in postoperative facial esthetics and occlusal relationships. Treatment plans requiring extended orthodontic treatment, or the need for supplementary surgical procedures (e.g., genioplasty or proplast augmentation) may require modification. The following case illustrates the special anesthetic and surgical problems involved in the management of a patient with myotonic dystrophy. Report of a Case A 26-year-old 5’6” slender white man seeking correction for what he described as his large jaw and poor bite was referred to one of the authors (JMF) for evaluation and possible correction of his problem. Physical findings included normal posture and gait, generalized weakness of the upper extremities with atrophy of forearm musculature, bilateral temporal muscle wasting and frontoparietal hair loss. The patient had a flexed right foot and diiculty releasing a clenched fist. He reported difficulty in speech upon awakening because of a “knotting” of his tongue, which resolved shortly thereafter. He denied any difficulties in swallowing or breathing, and denied a history of cardiac problems. There was no other significant past medical history. These findings were all consistent with MD, the diagnosis of which had been made by a neurologist a year prior to the examination. The family history revealed that the patient’s paternal grandfather and father apparently had had MD, although definitive diagnoses had never been made. His older brother (and only sibling) had been diagnosed as having MD by the same neurologist shortly before his own diagnosis had been made. Maxillofacial evaluation revealed a long, trapezoidal face with a prominent square chin, large mandible, lip competence with strain and no labiomental fold (Fig. 1A). The
KAUFMAN
ET AL
patient showed 7 mm of maxillary anterior tooth at rest. The tooth-lip relationship was strongly suggestive of vertical maxillary hyperplasia. There was a full complement of maxillary and mandibular teeth, with good arch form except for anterior crowding (Fig. 1B). Anterior bite was edge-to-edge, and there was a slight lingual cant of the lower incisors. The patient functioned in an Angle Class III molar relationship. The maxillary dental midline was coincident with the facial midline, while the mandibular dental midline deviated 3 mm to the left. There was no deviation of the mandible upon opening, no pain or noise from either TMJ, and no history of subluxation. Cephalometric evaluation confirmed our clinical impression of increased lower facial height. His mandible demonstrated an excessive vertical growth pattern which is consistent with vertical maxillary excess (Fig. 10. Our goal was to reduce lower facial height, reduce chin prominence, and reduce vertical maxillary excess, and in so doing, to reduce the amount of visible maxillary anterior tooth. Presurgical orthodontic treatment using edgewise direct-bonded brackets would correct the linguoversion of the lower incisors and thereby eliminate the lower anterior crowding. The anterior edge-to-edge occlusion would then be corrected surgically, the dental midlines made coincident, and a Class I molar relationship achieved. Under ideal circumstances, we would treat this case by utilizing a LeFort I osteotomy to reduce maxillary vertical hyperplasia and a mandibular ramus procedure to retrude the mandible and thereby correct occlusal relationships and reduce mandibular length. Mandibular autorotation would correct lower facial height. This treatment plan, however, would necessitate the use of MMF. In an effort to avoid this, an alternate treatment plan was devised. A LeFort I alveolar osteotomy would still be used to reduce maxillary vertical excess and allow for mandibular autorotation. To correct the resulting anterior cross-bite, align the dental midlines, and avoid MMF, a mandibular anterior subapical osteotomy would be performed (after extraction of lower first premolars). In order to achieve a Class I molar relationship, maxillary first premolars would be extracted and the posterior segments of the maxilla would be advanced. Stabilization would be achieved with individual maxillary and mandibular occlusal splints, the maxilla being stabilized superiorly by suspension wires. The need for MMF would be avoided. With both arches in their new positions, a 5-mm wedge genioplasty would be done to further reduce lower facial height and retrude the chin point. Hospital Course. After acceptance of our treatment plan and consultation with his neurologist, the patient was admitted to the Albert Einstein College Hospital for surgery. The results of preoperative laboratory evaluation, including SMA6 and SMA12 test batteries, prothrombin time, CBC, EKG, chest radiography, and urinalysis, were within normal limits, except for a slight elevation of creatine phosphokinase to 157 mIU/ml (normal range O-145) which was considered by the anesthesiologist to be insignificant. A potentially difficult intubation was anticipated because of a prominent anteriorly positioned cricothyroid cartilage. The patient was sedated preoperatively with meperidine, hydroxyzine, and atropine. The temperature in the operating room was 80” E The patient was placed on a cooling mattress and all emergency drugs including dantrolene were available. An
669
esophageal temperature probe was used for monitoring. Anesthesia was induced with enflurane and nitrous oxide. Thiopental and muscle relaxants (depolarizing or nondepolarizing) were not used. A cardiac monitor on lead II was employed. Under deep surgical anesthesia nasotracheal intubation was achieved with difficulty. Induction was otherwise smooth, and the patient was prepared and draped in the usual manner. Lidocaine with l/100,000 epinephrine was injected into the maxillary and lower anterior mucobuccal folds for hemostasis. After extraction of the lower first premolars, a lower subapical osteotomy was performed in the routine manner and the prefabricated lower occlusal stent was wired into place. Below the osteotomy, S-mm wedge of bone was removed and the chin point repositioned superiorly and posteriorly and ligated in place with 25gauge wire. The incision was then closed with 3-O chromic suture. In the maxilla an incision was made from the second molar anteriorly to the mesial of the second premolar bilaterally. An anterior horizontal incision was also made from the distal of the left canine to the distal of the right. Periosteum was reflected to expose the labial plate of bone, from which a premeasured width was surgically removed. A total labial osteotomy from pterygoid plate to pyriform rim bilaterally was performed, thus allowing access through which the palatal osteotomy was made trans-antrally. The pterygoid plates were then cleaved with a curved osteotome and total downfracture of the dentoalveolar segment of the maxilla was accomplished. The upper first premolars were extracted and vertical osteotomies through the extraction sites divided the dento-alveolar segment into three segments. All three segments were intruded, the posterior segments were advanced, and the maxillary occlusal splint was then wired to the three maxillary segments. The mandible was then closed until the maxillary and mandibular splints keyed together. This determined the final position of the maxilla, which was then secured to the stable midface with suspension wires from the buttress and pyriform rims bilaterally. The maxillary incision was closed with 3-O chromic suture. From both a surgical and anesthetic standpoint, the patient tolerated the procedure very well. Total blood loss was 450 ml; he received 1,700 ml of lactated Ringer’s solution and dextrose intraoperatively. Cardiac arrhythmias were not seen, and there was no problem with ventilation. The temperature remained constant at 36” C throughout surgery. There were no episodes of muscle rigidity or manifestations of myotonia throughout surgery. Upon leaving the operating room, the patient was breathing spontaneously but remained intubated. In the recovery room, management included a cardiac monitor and T-tube humidifier. The patient’s condition remained stable, and the trachea was extubated two hours postoperatively, after return of laryngeal reflexes and adequate tidal volume. Beginning on the evening of the day of surgery the patient began taking fluids orally with minimal difficulty. He quickly increased his fluid intake by the second postoperative day, and the intravenous line was discontinued. He ambulated early and was able to avoid postoperative atelectasis by adhering to a regimen of coughing and deep breathing. Postoperative SMA6 tests and CBC were normal, and he remained afebrile. He was discharged to home on the fourth postoperative day. Weekly postoperative visits followed his uneventful recovery. He reported no difficulty at any time in swal-
670
FIGURE 1. Preoperative appearance. A (rap), full face and profile. B (middle), occlusion. C (bottom), lateral cephalogram.
lowing or breathing. Curiously, he noticed an improvement in early morning speech and the disappearance of the “tongue-knotting” he had been experiencing before the operation. The occlusal splints were removed in the fifth postoperative week and stabilization was maintained with orthodontic arch wire. Orthodontic adjustments were continued every four weeks. One year postoperatively (Fig.
KAUFMAN
ET AL
FIGURE 2. Postoperative appearance. A (top), full face and profile. B (middle), postorthodontic occlusion. C (bottom), lateral cephalogram. 2) the patient’s occlusion
is stable and his myopathic face has been significantly altered. The patient is very satisfied with all aspects of the surgical result.
Summary The surgical and anesthetic considerations of orthognathic surgery for a patient with myotonic dys-
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MYOTONIC DYSTROPHY
trophy are discussed. A case report is presented demonstrating how a surgical treatment plan can be modified to avoid the potential postoperative problems associated with this disease. References 1. Dalal FY, et al: Dystrophic myotonia: a multisystem disease. Can Anaesth Sot J 19:436, 1972 2. Bhatt GP, Vijayan N, Dreyfus PM: Myotonia, a review of its clinical implications. Calif Med 114:16, 1971 3. Mudge BJ, Taylor PB, Vanderspek AFL: Perioperative hazards in myotonia dystrophy. Anesthesia 33:492, 1980
J Oral Maxillofac 41571675.
4. Casey EB, Amirioff MJ: Dystrophic myotonia presenting with dysphagia. Br Med J 22:443, 1971 5. Thayer A, Harley H, Crenshaw: Oral manifestations of myotonic muscular dystrophy. J Am Dent Assoc 72:1405,1%6 6. Wald C: Myotonia dystrophy-sedative and anesthetic management. Oral Surg 39:886, 1975 7. Kent JN, Winslow JR: Correction of severe dentofacial deformity association with myotonia congenita. J Oral Surg 36: 129, 1978 8. Kamiishi H, Ohtsuka H, Shioya N: Correction of myopathic face associated with myotonic muscular dystrophy. J Maxfat Surg 548, 1977 9. Petri WH, Stump TE: Familial dystrophic myotonia: report of a case. J Oral Surg 35:667, 1977
Surg
1983
Leiomyoma
of the Right Lower Gingiva:
A Case and a Review of the Japanese Literature HIROTSUGU
YAMAMOTO,
DDS, MINORU TAKAGI, DDS,* SHIGEO OTAKE, DDS, AND MOTOH OHMORI, DDS,t
Leiomyomas which are common benign tumors of smooth muscle, are infreauentlv encountered in the oral cavity.] There are few reports of ultrastructural studies of oral leiomyomas. We present a case of leiomyoma of the lower gingiva which was diagnosed on the basis of the ultrastructure. Twentynine cases of oral leiomyoma reported in Japan are reviewed.
Grossly, the resected tumor was 4.8 x 2.8 x 2.6 cm in size and had a solid gray cut surface with a partially fascicular structure (Fig. 2). Microscopically, the tumor was not completely encapsulated. It was composed of interlacing fascicles of spindle cells which had slightly
Report of a Case An 18-year-old Japanese girl was referred by her private dentist to our University Hospital on April 27, 1981. There was a painless mass of the lingual gingiva of the right lower second molar. It had been present for two months, but had rapidly grown during the last several days. The patient had no remarkable past history. The tumor was sessile in character and a gray color (Fig. 1). The second molar was slightly mobile to palpation. Radiographs revealed slight horizontal resorption of the alveolar bone in the right lower molar region. Resection of the tumor was performed on June 6, and there has been no recurrence since. Received from the Departments of Clinical Pathology and Oral Surgery,t Nihon University School of Dentistry, 2-870-1, Sakaecho-Nishi, Matsudo, Chiba 271, Japan. * Department of Oral Pathology, Faculty of Dentistry, Tokyo Medical and Dental Universitv. Tokvo. Jaoan. Address correspondence and rep&t requests to Dr. Yamamoto.
FIGURE 1. Clinical appearance of the tumor of the right lower lingual gingiva.