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Biomedical subjects

R L Anderson

Publications and source records attributed to R L Anderson.

At least 397 records · Page 22Linked to original sources
PubMed1981

Therapy-related preleukemic syndrome.

Eight patients developed the preleukemic syndrome after having been exposed to cytotoxic drugs for other primary diseases. All eight subsequently developed acute nonlymphocytic leukemia (ANLL). Survival following the onset of the preleukemic syndrome ranged from 5-34 months with a median of 11 months. Once overt leukemia developed median survival was three months. No patient responded to conventional antileukemic therapy. A higher incidence of chromosomal abnormalities was noted in bone marrow cells of this group (five of six) when compared with a larger group of preleukemic patients not known to have been exposed to mutagens (four of 21). In addition, two patients had second chromosome studies after overt leukemia developed and there was no evidence of cytogenetic clonal evolution. The clinical course and cytogenetic data in these patients attest to the relevance of our criteria in identifying the preleukemic syndrome and suggest that the leukemic clone was fully established during the preleukemic phase. Thus, patients previously exposed to cytotoxic therapy who develop the preleukemic syndrome may be viewed as having early leukemia.

Bone Marrow↗
PubMed1981

Temperature-induced homeoviscous adaptation of Chinese hamster ovary cells.

Exponential and plateau phase Chinese hamster ovary cells were maintained for 3 days at 32, 37, 39 or 41 degrees C. The effect of growth temperature on the fluidity and composition of the cellular membranes, and on the ability of the cells to resist a subsequent heat treatment at 43 degrees C, was measured. Cells grown at temperatures above 37 degrees C displayed increased resistance or tolerance to a 43 degree C heat treatment, whereas cells grown at 32 degrees C were sensitized to heat. Extensive cell division was not required for expression of heat tolerance. Membrane fluidity, as determined by the degree of rotational mobility of the fluorescent probe diphenylhexatriene, decreased with increasing growth temperatures, but the relationship did not hold in exponential phase cells grown at 32 degrees C. The cholesterol : phospholipid molar ratio correlated with the fluorescence polarization values, suggesting that the cells are able to adjust membrane fluidity by varying the concentration of cholesterol. The results are compatible with the concept of homeoviscous adaptation: that organisms strive to maintain an optimal level of membrane fluidity and when grown at a different temperature will alter the lipid composition in order to maintain this level. Up until now, cholesterol has not been implicated in this process.

Animals↗
PubMed1981

Transorbital decompression. Indications and results.

In a few patients with Graves' disease, visual loss related to an optic neuropathy develops. Clinical and radiologic evidence suggests that the mechanism of visual loss is optic nerve compression in the orbital apex. Steroids may offer improvement, but often the condition recurs unless high doses are maintained. Orbital decompression provides dramatic visual and cosmetic improvement in most cases. A transorbital approach suitable to the experienced orbital surgeon for decompression of the orbital floor and medial wall has been presented in a companion article. Results of this approach in 12 eyes with visual loss unmanageable by steroid therapy indicate a gratifying improvement in vision. Strabismus is the most frequent complication. Results with follow-up ranging from six to 18 months are encouraging and comparable to the results obtained with other methods of surgical decompression.

Adult↗
PubMed1981

Transorbital approach to decompression in Graves' disease.

Patients with Graves' disease have an increased volume of orbital tissue that sometimes results in serious functional and cosmetic problems. Visual loss may result from optic nerve compression in the orbital apex. Surgical decompression provides space for expansion of orbital tissues and often results in dramatic improvement. A transorbital approach to decompression of the orbit, appropriate for the ophthalmologist with adequate orbital experience, is presented. A lower eyelid incision is used in the manner of exploring a blow-out fracture. The majority of the orbital floor and the entire ethmoidal complex are removed. Removal of bone to the orbital apex is emphasized in cases of optic neuropathy. A comparative study of the indications, results, and complications of this procedure vs other techniques of decompression for Graves' disease is presented in a companion article.

Ethmoid Bone↗
PubMed1981

Complications of cryosurgery.

We describe 70 patients who underwent cryosurgery to the lids during a two-year period. Of the 58 receiving adequate follow-up, approximately one fourth had complications thought to be directly caused by cryosurgery. These include visual loss, lid notching, corneal ulcer, acceleration of symblepharon formation, xerosis, cellulitis, activation of herpes zoster, skin depigmentation, and severe soft-tissue reaction. In addition, 9% of the lids showed possible induction of trichiasis in areas adjacent to treatment. More than two thirds of patients with conjunctival shrinkage or grafted or irradiated lids had adverse effects, with one case of permanent visual loss. Misdirected lashes were successfully eliminated with a single double freeze-thaw technique in 90% of lids treated. Cryosurgery for aberrant lashes and some benign lid lesions is the most effective method of therapy presently available, but one must be aware of its potential complications. It has a low complication rate in "normal" lids, but should be used with caution in patients with conjunctival shrinkage or in those with grafted and/or irradiated lids.

Adolescent↗
PubMed1981

Sinus involvement in inflammatory orbital pseudotumor.

Orbital pseudotumor is a difficult diagnosis to establish preoperatively. The relationship between sinus disease and orbital pseudotumor is controversial. We describe two patients with unilateral proptosis, diplopia, palpable orbital masses, ocular discomfort, and sinus problems of short duration. Echographically, both had low reflective masses in the orbit and the adjacent sinuses. Roentgenograms and echograms were interpreted as showing erosion of the bony orbital wall. A presumptive diagnosis of sinus malignant neoplasm with orbital extension was made. Sinus histopathologic examination in one case and nasal histopathologic examination in the other showed chronic inflammatory changes compatible with the diagnosis of pseudotumor. At orbitotomy, one patient had vessels communicating between the orbital and sinus lesions, and both patients had irregular pitting of the bone next to the histologically proved orbital pseudotumors. The lytic erosive changes predicted preoperatively were not present. Simultaneous orbital and sinus pseudotumors seem to be a distinct clinicopathologic entity. Those concerned with the diagnosis and management of orbital disease should be aware of this entity.

Adult↗
PubMed1981

Lid splitting and posterior lamella cryosurgery for congenital and acquired distichiasis.

Congenital distichiasis is a rare condition with an accessory row of lashes at the Meibomian gland orifices. We suggest "acquired distichiasis" as an appropriate term for the accessory row of lashes in or near the Meibomian gland orifices, occurring as a result of such conditions as Stevens-Johnson syndrome, ocular pemphigoid, or chemical and physical injuries. We report a new treatment technique in which the eyelid is divided along the gray line then followed by cryotherapy to the posterior lid lamella. This removes the distichiatic lashes without damaging the normal lashes in the anterior lid lamella and avoids depigmentation. Histologic examination demonstrates the aberrant lashes result from a metaplasia of tissues in or around the Meibomian glands. Thirteen eyelids with acquired distichiasis and four eyelids with congenital distichiasis have been followed up for eight to 48 months. All have been greatly improved.

Adolescent↗
PubMed1981

Blepharospasm surgery. An anatomical approach.

Essential blepharospasm is an idiopathic, progressively debilitating disease leading to blindness. Years of forceful spasms result in brow ptosis, dermatochalasis, and, frequently, levator aponeurosis and lateral canthal tendon defects. Following standard neurectomy procedures, the facies droop, brow ptosis and dermatochalasis worsen, and ptosis and canthal tendon laxity suddenly become more evident. We describe a procedure involving meticulous extirpation of all accessible orbicularis oculi, procerus, corrugator superciliaris, and facial nerves in postorbicular fascia. This extirpation of eyelid protractors is combined with browplasty with fixation to frontalis and reinforcement of the levator aponeurosis to strengthen the retractors. Our technique opens the eye just as effectively as standard facial neurectomy procedures, simultaneously corrects associated anatomical deformities, and avoids facial paralysis. Gratifying results were obtained in 15 patients followed up for six to 38 months.

Aged↗
PubMed1981

A curriculum for the psychiatric training of family physicians.

This curriculum is designed with the expectation of considerable involvement by family physicians in mental health care delivery. Psychiatry education is initiated early, before attitudes become fixed, to emphasize self-reliance and mental health problem-solving skills, to make the learning experience longitudinal, and to integrate psychiatric training into the rest of the residents' curriculum. Seminars, clinical experience, and liaison with a mental health team are all utilized in the training design. The effectiveness of this training program will be studied over time to obtain needed data about the best teaching model for the mental health role of the family physician.

Curriculum↗
PubMed1981

Giant cell (reparative) granuloma of the orbit.

Clinically and histologically, there exists considerable controversy as to what constitutes a giant cell tumor. There is an increasing awareness that the term giant cell tumors should not be used indiscriminately in describing lesions of the mandible, maxilla, and facial bones which contain multinucleated giant cells. This paper reports a rare case of giant cell reparative granuloma of the orbit. The differentiation between giant cell reparative granuloma and the true giant cell tumor is discussed and a description of the visual symptomatology associated with these lesions of th sphenoid bone is presented. These tumors must be removed completely to prevent recurrence.

Adolescent↗
PubMed1981

The aponeurotic approach to eyelid retraction.

A technique for the upper lid retraction that involves an anterior approach similar to aponeurotic ptosis surgery is presented. Instead of advancing the aponeurosis, it is recessed and Müller's muscle is completely extirpated. The lateral horn of the levator must be cut to relieve the marked temporal elevation of the eyelid. Lid height and contour are adjusted intraoperatively with patient cooperation. In the lower lid, the retractors are recessed via a conjunctival approach unless simultaneously performed with orbital decompression. Any amount of lid retraction may be corrected by this technique in the upper lid and up to 3 mm of lower lid retraction can be corrected. Lid height in both the upper and lower lid is lasting and predictable. Thirty-one patients (63 eyelids) have been operated on using this technique with good results. Results in 17 patients (35 eyelids) with follow-up ranging from 8 to 42 months are presented.

Adult↗
PubMed1981

Tarsal strip procedure for correction of eyelid laxity and canthal malposition in the anophthalmic socket.

Surgically anophthalmic sockets commonly have laxity of the lower eyelid, inferior displacement of the lower eyelid and lateral canthus, shallowing of the inferior fornix, and a deep superior sulcus. These deformities result in difficulty in prosthesis retention, pooling of tears and mucus, epiphora and lower eyelid irritation, and poor cosmesis with an appearance of facial asymmetry. The causes of these problems are numerous, but the main anatomic deformity is a marked laxity and elongation of the lateral canthal tendon. The tarsal strip procedure is ideal for correcting or improving these deformities simultaneously with one simple procedure. We are very pleased with our results in 26 patients with surgically anophthalmic sockets in which this procedure was utilized. We highly recommend the tarsal strip procedure not only to correct these conditions in anophthalmic sockets but in almost any condition where laxity of the eyelids or canthal malposition requires surgical correction.

Adolescent↗
PubMed1981

Epidemic nosocomial meningitis due to Citrobacter diversus in neonates.

Five infants born at one hospital over a two-year period developed meningitis due to a serotype O2 strain of Citrobacter diversus; four infants developed brain abscesses due to this organism. The initial prevalence of stool colonization in infants was 79%; eventually 140 infants (10%) and six nurses (6%) were found to be colonized. One colonized infant remained in the hospital for the entire two-year period. The strains were of two biotypes marked by the presence (biotype d) or absence (biotype a) of fermentation of sucrose and dulcitol. The biotype d strain was found in the five infants with meningitis, 110 asymptomatic infants, and five nurses. The biotype a strain, which was isolated from 30 infants and one nurse, did not cause disease. Colonized infants were distinguished by intensive care therapy (P = 10-31), gavage feeding (P = 0.036), and prenatal intrauterine monitoring (P = 0.037). These findings suggest a fecal reservoir and person-to-person transmission of C. diversus. Measures to control the outbreak cost about $110,000.

Birth Weight↗