Biomedical subjects

N S Karp

Publications and source records attributed to N S Karp.

22 records · Page 2Linked to original sources

PubMed1990

Bone lengthening in the craniofacial skeleton.

The process of bone lengthening by cortical fracture and gradual distraction of callus has become well established in the enchondral bones of the extremities. In this study the principles of bone lengthening were applied to the membranous bone of the craniofacial skeleton using the growing dog mandible as a model. Six mongrel dogs five months of age were studied. A unilateral, periosteal-preserving angular corticotomy was performed, and an external minilengthening device was fixed to the mandible perpendicular to the corticotomy. After 10 days of external fixation, the mandible was lengthened 1 mm/day for 20 days and then held in external fixation for 56 days (8 weeks) after which all dogs were killed. Anthropometric measurements and histological analysis of the specimens confirmed that bone lengthening had occurred and that new cortical bone was formed in the expanded areas.

Animals↗

PubMed1990

The effect of early fronto-orbital advancement on frontal sinus development and forehead aesthetics.

The frontal sinuses make an important contribution to normal forehead and glabellar contour. This study was designed to test our clinical impression that early fronto-orbital ("frontal bone") advancement could have an adverse effect on frontal sinus development and consequently on forehead aesthetics. A retrospective study was conducted on 11 patients who had undergone fronto-orbital advancement and also had a long period of follow-up at the Institute of Reconstructive Plastic Surgery at New York University. The longitudinal cephalometric data were compared with unoperated controls. With one exception, no patient who underwent bilateral fronto-orbital advancement developed a frontal sinus, and all such patients had a flattened brow contour when compared with unoperated patients, of whom 82 percent developed at least one frontal sinus. Of the three patients who underwent unilateral fronto-orbital advancement for plagiocephaly (flattened forehead), two developed a frontal sinus but only on the unoperated side and one developed bilateral frontal sinuses. The two patients with unilateral frontal sinus development had a particularly obvious deformity resulting from normal glabellar projection on the unoperated side and a flattened contour on the operated side. Fronto-orbital advancement affects forehead aesthetics and should be performed only in infant patients with moderate to severe deformities. patients with plagiocephaly whose deformity is sufficiently severe to warrant surgery should preferably undergo bilateral fronto-orbital advancement (by the technique described) rather than unilateral advancement in order to avoid the brow asymmetry that results from unilateral frontal sinus development.

Adolescent↗

PubMed1990

Thoracotomy for metastatic malignant melanoma of the lung.

The outcome of 29 patients who underwent lung resection for treatment of metastatic malignant melanoma from January 1976 to November 1988 was studied. Twenty-two patients underwent total resection for cure of all apparent metastatic disease, whereas seven patients did not undergo total resection. Of the 22 patients who underwent curative resection, the median survival was 11 months, with a 2-year survival of 13.6% and a 5-year survival of 4.5%. Four patients who underwent curative resection are currently alive and free of disease, with one patient surviving more than 10 years. The patients who underwent palliative resection had a median survival of 5 months, only one patient living longer than 10 months. The difference in survival of the patients who underwent curative resection compared with palliative resection was statistically significant. The thickness of the primary cutaneous malignant melanoma, the presence of regional lymph node metastases, the disease-free interval from primary diagnosis to metastatic pulmonary disease, and whether one or two metastatic nodules were removed during curative lung resection were not statistically significant in altering survival. These results demonstrate that although prolonged survival for metastatic melanoma is rare, lung resection in selected patients may be associated with long-term survival.

Adult↗

PubMed1989

Primary hyperparathyroidism associated with two enlarged parathyroid glands.

An increasingly recognized although small percentage of patients with primary hyperparathyroidism have enlargement of two parathyroid glands. We have treated nine patients with primary hyperparathyroidism associated with such double parathyroid gland enlargement. In four of these patients, marked asymmetry of the two enlarged glands was noted and the failure to recognize and excise a second enlarged parathyroid gland resulted in persistent or recurrent hyperparathyroidism. In one of these patients, the second enlargement was present in a super-numerary mediastinal gland. The subsequent excision of the second enlarged parathyroid gland resulted in normocalcemia in each instance. This contrasts with five patients in whom initial excision of two enlarged glands resulted in normocalcemia with no recurrence of hypercalcemia. Only three patients fulfilled the histologic criteria of true double adenomas. The remainder showed multiglandular hypercellularity. This experience supports identifying all parathyroid glands and recognizing that even minimal enlargement of a gland may be important pathophysiologically, regardless of its histopathologic classification. Excision of both enlarged glands, even if asymmetric, is appropriate.

Adult↗