PubMed Health⌕ Search

Biomedical subjects

R J Konior

Publications and source records attributed to R J Konior.

15 recordsLinked to original sources
PubMed2001

A histologic analysis of three-dimensional versus two-dimensional tissue expansion in the porcine model.

OBJECTIVE: Recently, a two-dimensional Silastic Dacron stretching skin device has been developed for scalp reduction surgery. Attached subgaleally, this device stretches skin over time, while avoiding the visible volumetric distention that is typical of three-dimensional tissue expanders. Unlike three-dimensional expanders, the histological changes observed with a two-dimensional stretching device have not been described in the literature. The present study compares the histological effects of two-dimensional and three-dimensional skin tissue expansion in the porcine model. STUDY DESIGN: A university Institutional Review Board-approved study in which 16 domestic piglets were used. The 16 piglets were divided evenly into four cohorts as follows: 1, 1-week control cohort; 2, 1-week experimental cohort; 3, 4-week control cohort; and 4, 4-week experimental cohort. METHODS: Tissue expanders (three-dimensional) and Dacron Silastic tissue stretchers (two-dimensional) were surgically inserted into the lateral skin of 16 domestic pigs. Animals were killed at either 1 or 4 weeks based on group assignment. Light microscopic ocular micrometry and stereological point counting were used to determine the depth of the epidermis, dermis, and subdermal adipose tissue layer; width of the panniculus muscle; diameter of sweat gland follicles; percentage ratio of dermal collagen, blood vessels, and tissue space; and epidermal mitotic index in 100 specimens. One-way ANOVA was used to evaluate statistical differences. RESULTS: Both tissue expanders yielded increased values compared with control subjects, with respect to epidermal, dermal, and fat widths and blood vessel counts, whereas adnexal structures in the panniculus muscle width were unaltered. CONCLUSIONS: Although statistically the two types of expansion produced histologically similar changes, the degree of change varied according to the type of expander that was used and the duration of tissue expansion. Most notably, three-dimensional expansion produced more tissue gain per unit area expanded at both the 1-week and the 4-week time intervals, and early (1-week) two-dimensional tissue expansion stimulated a greater angiogenic response than three-dimensional expansion. These findings will assist the surgeon in understanding the physical changes that occur with these two forms of tissue expansion, as well as the potential clinical advantages and shortcomings of each method.

Adipose Tissue↗
PubMed1995

Effect of magnetic resonance imaging on implantable eyelid weights.

Implanted upper eyelid gold weights are used to prevent corneal injury in patients with facial nerve paralysis. Some of these individuals require postoperative radiographic surveillance for recurrent lateral skull base disease. Magnetic resonance imaging (MRI) provides the most accurate radiologic assessment; however, there is concern about the safety of performing MRI in patients with any metallic implant. Potential risks include local tissue heating and implant migration. Gold weights of 0.8 and 1.4 g were placed in an open chamber and were exposed to a magnetic field of 1.5 T. There was no measurable motion or displacement of the weights. The results were similar in 6 rats in which gold weights were subcutaneously implanted. Additionally, histologic examination of the implant sites revealed no adverse tissue effects attributable to MRI-generated heating of the implants. When carbon steel implants in the rat model were subjected to the magnetic field, there was no displacement of the implants and no adverse tissue effects were noted, despite the fact that a carbon steel implant in an open chamber demonstrated significant migration. The absence of motion of the gold weight implants combined with the lack of adverse tissue effects suggests the relative safety of performing MRI in patients with previously placed gold weights as upper eyelid implants.

Animals↗
PubMed1993

Irradiated cartilage grafts in the nose. A preliminary report.

Many nasal deformities require some form of graft or implant material for complete correction. Various well-recognized disadvantages are associated with currently used autografts, allografts, and alloplastic materials, thereby maintaining a continued search for the ideal nasal graft. Irradiated homograft costal cartilage is an allograft that has been used with variable success in the head and neck region. Isolated reports have suggested favorable results with irradiated homograft costal cartilage implantation in the nose. This study details the findings of 306 irradiated homograft costal cartilage grafts that were used in 122 nasal augmentation procedures.

Adult↗
PubMed1992

Facial paralysis reconstruction with Gore-Tex Soft-Tissue Patch.

No procedure perfectly restores a face paralyzed by surgical ablation of the facial nerve. Although dynamic reconstructive procedures are preferred for treating patients with complete facial paralysis, various conditions contraindicate their use, making static suspension of the paralyzed face a reasonable surgical alternative. Expanded polytef soft-tissue patch (polytetrafluoroethylene; Gore-Tex Soft-Tissue Patch, Gore-Tex, W. L. Gore & Assoc Inc., Flagstaff, Ariz) was used to help correct midfacial and perioral asymmetries in 11 patients with complete unilateral facial paralysis. All patients had previous surgical ablation of the facial nerve and were not considered good candidates for dynamic facial reconstruction. Midfacial and perioral asymmetries were improved in all patients using this technique of static soft-tissue suspension. One postoperative infection and two cases of postoperative suture extrusion were observed in the patient population. Other complications associated with the use of Gore-Tex Soft-Tissue Patch for facial suspension were limited to technical factors.

Adolescent↗
PubMed1991

Controlled nasal tip rotation via the lateral crural overlay technique.

Pronounced nasal tip ptosis is generally regarded as an unattractive facial feature. Besides its aesthetic ramifications, marked inferior displacement of the nasal tip adversely affects nasal function by restricting airflow through the nares. We present a new technique that is a modification of a lateral crural flap procedure that was described in 1975. This technique, which is performed using an open rhinoplasty approach, predictably rotates the nasal tip upward by restructuring the alar cartilages via controlled overlay of the lateral crura. When overprojection accompanies tip ptosis, the controlled lateral crural overlay technique permits graduated retrodisplacement of the tip, in addition to rotation, giving the surgeon full control for reliably and accurately repositioning the nasal tip superiorly and posteriorly.

Female↗
PubMed1990

Dome truncation for management of the overprojected nasal tip.

The nasal tip highlights the facial profile, and in its most aesthetic configuration subtly projects anterior to the dorsum to create a soft supratip break. Overprojection of the tip in relation to the vertical facial plane and the nasal dorsum represents one variant of nasal-facial disproportion that can adversely affect an otherwise pleasant facial appearance. Several strategies for reducing either the lateral or the medial crus to deproject the tip have been suggested. This article describes a method of direct truncation of the dome using an external rhinoplasty approach that can reliably produce tip retrodisplacement while maintaining, or enhancing, tip rotation. Tip definition and projection are optimized by precise, direct reduction of the overprojected dome region and accurate sculpting and realignment of the remaining crural units. When the tip is retrodisplaced, alar flaring can occur; therefore, alar base reduction can substantially enhance the final outcome.

Cartilage↗
PubMed1990

Selected approaches to the aging face.

The desire for a more attractive, youthful appearance knows no upper age limit. We highlighted a number of conditions that are more severe or more frequently seen in the geriatric patient. Appropriate, tested, and logical techniques for their correction are described. Figure 2 illustrates the results of these techniques.

Chemexfoliation↗
PubMed1989

Advances in nasal tip surgery. The lateral crural steal.

Increasing nasal tip projection, rotation, and definition have classically been attempted through a variety of lobular cartilage incising or excising techniques. Resultant long-term complications, including bossing, alar notching, pinched tips, and alar collapse, have occasionally resulted from the use of these techniques. The majority of these complications have arisen secondary to a loss of structural support following the interruption of the lower lateral cartilages. This article describes the "lateral crural steal," a method of increasing nasal tip projection and nasal tip rotation while preserving the integrity of the lobular cartilage complex. The procedure uses the external rhinoplasty approach for exposure. By elevating both the dorsal and the vestibular skin from the domes of the lobular cartilages, the lateral crura may be advanced onto the medial crura to further project the nasal tip and to reorient the tip upward. This technique along with its philosophy and long-term follow-up results are presented.

Follow-Up Studies↗
PubMed1989

Surgical management of severe laryngomalacia.

Infants and children with laryngomalacia exhibit varying degrees of upper airway obstruction and dysphagia. Although the disorder is usually self-limited, the potential exists for symptoms so severe that operative intervention cannot be avoided. Relief of progressive airway compromise traditionally has involved bypassing the obstruction with tracheotomy. Recently, endoscopic surgical management of the most severe cases has been reexamined by the authors and others. Thirteen infants and children underwent supraglottoplasty (also referred to as epiglottoplasty or partial arytenoidectomy) for severe, complicated laryngomalacia. Endoscopic laser removal of flaccid supraglottic tissue resulted in improvement of the airway in all patients. In most patients, associated symptoms improved or completely resolved. Supraglottoplasty is an effective alternative to tracheotomy in carefully selected patients with severe laryngomalacia.

Airway Obstruction↗
PubMed1988

Severe hypertrichosis of the external ear canal during minoxidil therapy.

Minoxidil is a potent peripheral vasodilator used to treat patients with severe hypertension that is unresponsive to other medications. Hypertrichosis of the forehead, face, neck, shoulders, upper part of the arms, and legs is a frequent side effect that occurs in the majority of patients that use this drug. This phenomenon appears to be due to increased blood flow to hair follicles, with resultant excessive hair growth. We describe a patient with severe hypertrichosis of the external ear canal resulting in chronic otitis externa and hearing loss.

Ear, Middle↗
PubMed1988

Superselective embolization of laryngeal hemangioma.

Diffuse upper respiratory hemangiomas are extremely rare lesions. Unlike the much more common congenital subglottic hemangiomas, diffuse upper respiratory hemangiomas do not resolve spontaneously and may prove quite recalcitrant to conventional forms of therapy. Superselective embolization, a highly successful technique for the management of head and neck vascular lesions, was used to effectively control an obstinate laryngotracheal hemangioma. Superselective embolization appears to provide yet another viable therapeutic option in the management of laryngeal hemangiomas.

Child↗