Search PubMed⌕ Search

Biomedical subjects

D A Keith

Publications and source records attributed to D A Keith.

At least 19 recordsLinked to original sources

Craniofacial skeletal deviations following in utero exposure to the anticonvulsant phenytoin: monotherapy and polytherapy.

OBJECTIVE: To identify and quantify the craniofacial effects from prenatal exposure to phenytoin monotherapy and polytherapy using cephalometric, hand-wrist, and panoramic radiographs and to determine if such deviations persist with age. DESIGN: Craniofacial structures of 28 anticonvulsant-exposed individuals were evaluated using 20 landmarks in lateral cephalometric radiographs and 19 landmarks in frontal cephalometric radiographs. Skeletal maturity was assessed using hand-wrist radiographs. Dental maturity and the presence of dental anomalies were evaluated using panoramic radiographs. Eleven individuals were re-evaluated 7 years later, on average, to determine the persistence of any measured deviations. SETTING AND SAMPLE POPULATION: Department of Growth and Development, Harvard School of Dental Medicine and Massachusetts General Hospital. Patients were recruited from several sources. OUTCOME MEASURE: The evaluated dimensions included linear, angular, and proportional measures. RESULTS: The most common deviations were decreased height and length of the maxilla, decreased length of the posterior cranial base, length of the mandible, cranial width and level of the cribriform plate, and a decrease in the Wits Appraisal assessment. The deviations were more significant in the polytherapy-exposed individuals than in the monotherapyexposed individuals. These deviations, especially in the maxilla, persisted with age as revealed in a re-evaluation of 11 individuals. CONCLUSION: The craniofacial skeletal findings among individuals exposed in utero to phenytoin monotherapy or phenytoin polytherapy, when considered in aggregate, suggest a mild pattern of maxillary hypoplasia that becomes more pronounced with age.

Abnormalities, Drug-Induced↗

Effect of orthognathic surgery on the temporomandibular joint in patients with anterior open bite.

This study examined the prevalence of temporomandibular joint (TMJ) signs and symptoms in patients with anterior open bite. The influence of orthognathic surgery on the TMJ in these patients and the interaction of occlusal and psychologic variables on the presence and/or persistence of pain was studied. A retrospective survey of 83 patients with an anterior open bite who underwent orthognathic surgery was carried out. Records were examined for the prevalence of abnormal TMJ signs and symptoms, including pain. A survey was mailed to these patients that consisted of: (1) the TMJ Scale, (2) the Symptom Checklist 90 (SCL90), (3) the Spielberger State-Trait Anxiety Inventory (STAI), and (4) a visual analog scale on which patients indicated their degree of satisfaction with the procedure. Thirty-seven (42%) patients responded to the survey, and 13 (15%) also attended a clinical and radiographic examination. Multiple regression analysis was used for statistical analysis of the factors contributing to the presence and/or persistence of pain. In the preoperative group, the prevalence of pain was 32%, dysfunction 40%, and limitation of opening 7%. Age and gender were significantly associated with the presence of pain. The overall prevalence of abnormal TMJ signs and symptoms was not significantly different after orthognathic surgery. An abnormal psychologic profile was the most significant factor associated with the presence and/or persistence of pain. It is concluded that that the prevalence of temporomandibular disorders in anterior open bite patients increases with age, is significantly higher in females, and is not influenced by other occlusal variables. Furthermore, orthognathic surgery does not significantly influence temporomandibular disorders in patients with anterior open bite. Female patients, particularly those with an abnormal psychologic profile, are at a higher risk of persistent postoperative TMJ pain.

Adolescent↗

Percutaneous stereotactic differential radiofrequency thermal rhizotomy for the treatment of trigeminal neuralgia.

PURPOSE: The purpose of this study was to evaluate the effectiveness of radiofrequency thermal rhizotomy (RTR) for trigeminal neuralgia, after failure of pharmacological management. PATIENTS AND METHODS: Two hundred fifteen patients underwent RTR from 1991 to 1996 and were prospectively evaluated. These patients were characterized by age, sex, side of the face, and division(s) involved. Patients were evaluated for pain relief, recurrence requiring or not requiring reoperation, and the type and rate of complications. They were followed-up by serial clinical evaluation and telephone interview. Patients were categorized into groups: 1) Successful result: excellent, good pain relief; and 2) Unsuccessful result: fair, poor, or no pain relief. The RTR group was compared with historical controls. Follow-up ranged from 9 to 68 months (mean, 32 months) and results were evaluated at early and long-term follow-up. RESULTS: At early follow-up (defined as immediately postoperatively to 6 months), pain relief of excellent or good quality (successful result) occurred in 198 of 215 patients (92%). Fair or poor or no pain relief (unsuccessful result) occurred in 17 (8%) patients. At long-term follow-up (>6 months to 68 months), recurrence of pain that required reoperation occurred in 24 patients (11%) and recurrence of pain that did not require reoperation (medically managed) occurred in 34 patients (16%). Dysesthesia developed in 18 patients (8%); seven patients (3%) had dysesthesia alone (medically managed) and 11 patients (5%) had dysesthesia with recurrence of pain (medically or surgically managed). "Anesthesia/analgesia dolorosa" developed in four patients (1.8%) and was medically managed. At long-term follow-up, 83% of patients had good to excellent pain relief (successful result). There were no mortalities, no significant morbidity, and a low rate of minor complications. CONCLUSION: With the use of this specific diagnostic approach and management algorithm, patients with trigeminal neuralgia can be successfully managed.

Adult↗

Chronic neurogenic facial pain: lack of response to intravenous phentolamine.

AIMS: Chronic neurogenic facial pain is commonly resistant to treatment and is often the source of significant patient morbidity. Adrenergic mechanisms are postulated to play a role in producing this type of pain, and adrenergic blocking agents are frequently used in clinical practice for pain control therapy. The analgesic effectiveness of an adrenergic blocking agent, intravenous phentolamine, was compared to saline and intravenous lidocaine in the present study using a single-blind protocol in patients with chronic neurogenic facial pain. METHODS: Thirty patients were studied whose common clinical features included pain for more than 6 months, unilateral trigeminal distribution, constant dysesthesia, and no evidence of pathology or known etiology. Phentolamine (30 mg), lidocaine (100 mg), and saline were each infused over periods of 5 to 10 minutes. Pain ratings were assessed every 4 minutes throughout each study period using a 10-point pain intensity scale. RESULTS: No patient reported subjective improvement of pain during or immediately following phentolamine or saline infusions alone. Sixteen of the 30 patients reported decreased pain following lidocaine infusion. In the majority of the patients, the duration of lidocaine analgesia was less than 30 minutes; however, some patients reported decreased pain for a longer time. CONCLUSION: The results do not support an adrenergic mechanism for chronic neurogenic facial pain. The response to lidocaine, a nonadrenergic, membrane-stabilizing agent, suggests that it may have clinical effectiveness in certain neurogenic facial pain patients.

Adrenergic alpha-Antagonists↗

New syndrome? Prominent, constricted ears with malformed condyle of the mandible.

We report on several relatives in 5 generations of one family with prominence of the ears, with a marked constriction at the junction between the lower and middle thirds of the pinna. Computerized tomography and radiographs in the propositus and his affected father showed abnormalities of the condyle of the mandible. The propositus had more severe changes in the condyle with microstomia and reduced range of motion of the mandible in the temporomandibular joint. There was no hearing loss or abnormalities of the bones of the middle ear.

Child↗

Posttraumatic gustatory neuralgia: a clinical model of trigeminal neuropathic pain.

Six cases are reported in which the primary complaint was episodic, recurrent facial pain that was triggered by a taste stimulus. The pain first occurred days to weeks after head and neck surgery. Patients reported that a food stimulus placed in the mouth evoked episodic, electric shock-like pain in a preauricular location on the surgical side. The smell of food or, less reliably, emotional excitement could also trigger pain. Mandibular movement did not evoke the pain, and between lancinating attacks there was either no pain or only mild discomfort. Following an episode of pain, there was a refractory period during which the pain could not be elicited. Physical examination demonstrated a preauricular sensory loss of variable distribution. No abnormal sweating or vasomotor findings were clinically apparent. No odontogenic, muscular, salivary gland, neurologic, or psychologic pathology was found to explain the clinical symptoms. The pain was not relieved with standard doses of anticonvulsants that are commonly used to treat trigeminal neuralgia. The duration of the recurrent pain symptoms in this group was 8 to 132 months without remission. Gustatory neuralgia may be a discrete syndrome that results from abnormal interactions between salivary efferent fibers and trigeminal sensory afferent fibers in the injured auriculotemporal nerve. The unique features of the disorder make it a potentially useful clinical model for the investigation of autonomic/sensory interactions in neuropathic pain.

Adult↗

Hyalinizing clear cell carcinoma: report of a case.

Hyalinizing clear cell carcinoma (HCCC) is a recently described low-grade malignant neoplasm of minor salivary glands. Of the thirteen reported patients with this neoplasm, the majority have occurred in the oral cavity of elderly women. We report another case and add further supporting evidence that hyalinizing clear cell carcinoma is a distinct pathological entity.

Adenocarcinoma, Clear Cell↗

Orofacial athletic injuries and involvement of the temporomandibular joint.

Injuries to the temporomandibular joint can range from contusion to complex displaced fractures. Major factors in the treatment of any injury are the patient's age and the stage in development of the temporomandibular joint and surrounding structures. A failure to diagnosis or the lack of proper treatment may lead to deformities. Following initial evaluation and management, vigorous mobilization of the joint remains a cornerstone of treatment.

Adolescent↗

Infratemporal space pathosis mimicking TMJ disorders.

The differential diagnosis of pain in the face and dysfunction of the masticatory system is complex. Although most diagnoses are readily made, common symptoms can occasionally belie more serious diseases. Each patient was originally treated for TMJ dysfunctions and subsequently was diagnosed as suffering from pathosis of the infratemporal space.

Actinomycosis, Cervicofacial↗

Pharmacologic treatment for chronic facial pain.

Chronic orofacial pain often requires pharmacologic treatment in conjunction with surgical, physical, and psychologic treatments. Myofascial pain, neuralgias, vascular pain, and limbic system dysfunction are the elements of orofacial pain that may respond to treatment with nonsteroidal anti-inflammatory drugs, anticonvulsants, membrane-stabilizing and monoaminergic medicines, respectively.

Anti-Inflammatory Agents, Non-Steroidal↗

Surgical treatment for temporomandibular joint problems.

Surgical intervention may be necessary for some patients with specific pathology or derangement of the temporomandibular joint as part of an overall management protocol. The current literature discusses the efficacy of arthroscopy, the treatment of the difficult problem of ankylosis, and the use of implants and autogenous and allogenic materials to replace the disk.

Ankylosis↗