Biomedical subjects

R S Knighton

Publications and source records attributed to R S Knighton.

12 recordsLinked to original sources

PubMed1991

The management of arteriovenous malformations in children.

Between January 1941 and June 1989, 46 children below the age of 18 with an arteriovenous malformation (AVM) were managed. There were 7 patients with AVM diagnosed before the age of 2; 10 patients were diagnosed between the ages of 3 and 10; and 29 patients were diagnosed between 11 and 18. There were equal numbers of male and female patients. Twenty-five of the AVMs were large (greater than 5 cm longest diameter). All 7 AVMs diagnosed before the age of 2 were large. The usual clinical presentation was congestive heart failure, bruit and an enlarging head. Three patients underwent excision with 2 deaths and 1 excellent result. In 11 patients (aged 3-18) with AVM without history of hemorrhage, 3 had excision with 2 excellent and 1 fair result. Four remained stable. Four developed progressive deficits or hemorrhage. In 10 patients (aged 3-18) with AVM and hemorrhage who were treated medically, 7 (70%) had an episode of re-hemorrhage. Three patients had excision of AVM after re-hemorrhage, but before the age of 18 with an excellent result. Eighteen patients (aged 3-18) with AVM and a single episode of hemorrhage underwent excision with 17 excellent or good results and 1 fair result. The overall mortality was 7%. Eighty-five percent of the children with excision of AVM had an excellent or good result. The best treatment for AVM in children is surgical excision.

Adolescent↗

PubMed1987

Meningioma in the parotid region.

Meningiomas occurring ectopically in the neck are exceptional. We report two patients who presented as parotid and parapharyngeal masses and analyze them along with 27 previously reported cases. Typical patients present with parotid or parapharyngeal masses and cranial nerve palsies. Meningioma is not considered in differential diagnosis. The tumor is an extension of an unsuspected intracranial mass, occasionally with associated multiple meningiomas or other neurogenic tumors. Ectopic meningiomas should be considered in patients with parotid and parapharyngeal masses, particularly those with cranial nerve deficits; jugular foramen syndrome is most characteristic. Associated occult intracranial and temporal bone tumors and the cranial form of neurofibromatosis should be suspected. Treatment of cervical meningiomas is excision. The most important aspect of intracranial-extracranial lesions is recognition and treatment of the intracranial portion.

Adolescent↗

PubMed1987

Extensibility of the lumbar and sacral cord. Pathophysiology of the tethered spinal cord in cats.

Tethered spinal cord, or tethered cord syndrome, describes a disorder manifested by progressive motor and sensory deficit in the legs and by incontinence. Tethered cord syndrome occurs when the elongated spinal cord is anchored by a thick filum terminale or other pathological structures. The underlying mechanism is impairment of oxidative metabolism in the lumbosacral cord. The authors studied the extensibility of various parts of lumbar, sacral, and coccygeal segments in experimental animals and correlated this with the oxidative metabolism in these segments. The filum terminale possesses far greater extensibility than any spinal cord segments and functions as a buffer in preventing the cord from overstretching. The lumbar, sacral, and coccygeal segments elongate under traction only below the attachment of the lowest pair of dentate ligaments. The lower the cord segment, the greater the percentage of elongation in spite of limited elasticity of the cord tissue; this greater percentage of elongation of the spinal cord correlates with increasing impairment of the oxidative metabolism and more severe neurological deficit. These findings explain such symptoms and signs as motor and sensory deficits in the legs associated with the human tethered cord syndrome, and correspond with the high clinical incidence of incontinence. The lower spinal cord segments elongated promptly within 3 seconds after the start of traction. This implies that repeated acute hyperextension and hyperflexion, as occurs in humans, may accentuate oxidative metabolic changes that have already been caused by chronic cord tethering. The authors conclude that the elongation of the spinal cord under traction parallels the degree of metabolic dysfunction.

Animals↗

PubMed1986

Cranial invasion by basal cell carcinoma.

The direct spread of basal cell carcinoma (BCC) into the bones of the cranium takes a long period. In its early stages, it may not be detectable by radiography or computerized tomography, but can be visible as pitting during surgery. Invasion through the thickness of the calvarium due to extension of a BCC of the scalp, or involvement of the cribriform plate by spread from an intranasal lesion, is serious. Examples of cranial invasion by BCC are presented. The methods used in diagnosis and treatment are outlined.

Aged↗

PubMed1984

Aggressive choroid plexus papilloma.

A young woman, who was initially treated for an Arnold-Chiari malformation, was found 7 years later to have a posterior third ventricular tumor. A superior cerebellar approach allowed total resection of the mass, which was an aggressive choroid plexus papilloma. The patient was treated with whole cerebrospinal axis radiation. There is no clinical or computed tomographic evidence of recurrence after 4 years. The literature is reviewed and a discussion of aggressive choroid plexus papilloma (carcinoma) is presented.

Adult↗

PubMed1976

Pulmonary neoplasm with solitary cerebral metastasis. Results of combined excision.

Twenty-two patients underwent excision of a primary pulmonary neoplasm and solitary cerebral metastasis. Six patients had metastatic tumor removed on two occasions and there was one operative death in 28 craniotomies. Seven of 22 patients (32 per cent) survived one year following craniotomy and were free of significant symptoms for one year. Survival for at least 9 months and freedom from significant symptoms was achieved in a total of 12 patients (55 per cent). Relief of severe neurologic symptoms for a minimum of 3 months was achieved in 17 patients (77 per cent). The over-all one-year survival rate was 45 per cent and the average survival period is 14 months with 3 patients still living. The following factors had a favorable bearing on the outcome: Stage 1 lung cancer at pulmonary resection, whole-brain radiation therapy, and a longer interval between pulmonary resection and cerebral metastasis. The experience encourages us to pursue an aggressive surgical approach to pulmonary neoplasm and solitary cerebral metastasis.

Adult↗

PubMed1970