Biomedical subjects

R K Dortzbach

Publications and source records attributed to R K Dortzbach.

At least 37 records · Page 2Linked to original sources

PubMed1995

Inverted papillomas that invade the orbit.

We describe 10 patients with inverted papillomas (IPs), uncommon endophytic epithelial tumors that arose in the nose, paranasal sinuses, and lacrimal sac, that invaded the orbit; review the world literature on IP; and discuss treatment options. Patients ranged in age from 49 to 72 years (mean age, 62 years; median age, 66 years). Six patients were men and four were women. Presenting symptoms and signs included a medial canthal mass (n = 5), epiphora/lacrimal drainage obstruction (n = 3), inability to wear eyeglasses (n = 2), diplopia (n = 1), and painful dentures (n = 1). Histopathologic examination was performed in each patient and revealed all patients to have areas with malignant transformation: six patients with IPs that contained areas of squamous cell carcinoma and four with areas of transitional cell carcinoma in the tumor within the orbit. Eight of the patients with IPs had a recurrence after initial resection. In two patients, the IPs were completely excised and did not recur; yet, follow-up was short. Eight patients required orbital exenteration for local control of disease. Nevertheless, local spread of tumor through bone to brain occurred in three patients with orbital involvement. Indeed, IPs that invade the orbit have a high incidence of malignancy and are locally aggressive tumors. Treatment is difficult, and the recurrence rate is high. Early, wide excision of this aggressive tumor provides the best chance of cure.

Aged↗

PubMed1994

Results of endonasal laser-assisted dacryocystorhinostomy.

BACKGROUND: Endonasal laser-assisted dacryocystorhinostomy has been a subject of much interest since its introduction in 1990, offering the potential advantages of decreased postoperative morbidity and the lack of a cutaneous scar. In this study, the authors report the results of 46 endonasal laser-assisted dacryocystorhinostomy procedures performed on 42 patients between February 1991 and July 1992. METHODS: The medical records of all patients undergoing endonasal laser-assisted dacryocystorhinostomy procedures were reviewed retrospectively in detail. Patients undergoing laser-assisted external dacryocystorhinostomies or conjunctivo-dacryocystorhinostomies and those with follow-up periods less than 4 months were not included in the study. RESULTS: A total of 46 endonasal laser-assisted dacryocystorhinostomy procedures were performed. Of these, 32 were successful and 14 failed after a single attempt, yielding a success rate of 70% (32/46). Of the 14 patients with failed procedures, 6 underwent a second endonasal laser-assisted dacryocystorhinostomy. Of these, five were successful. The success rate calculated on the basis of one or two attempts was 80% (37/46). CONCLUSIONS: The science and technology of endonasal laser-assisted dacryocystorhinostomy is undergoing a continuous process of evolution as a number of modifications are introduced, including better patient selection, more complete tissue removal at the osteotomy site, and the adjunctive use of mitomycin C. As this process continues, it is likely that the success rates in this modality will improve, making it an increasingly attractive alternative to external dacryocystorhinostomy.

Dacryocystorhinostomy↗

PubMed1994

Oculinum injection-resistant blepharospasm in young patients.

Botulinum toxin has recently been used as a nonsurgical treatment for blepharospasm and other facial dyskinesias. This report describes four patients between the ages of 32 and 37 years who failed to respond to botulinum injections for severe blepharospasm. Other than age, no other features could be identified in these patients that would differentiate this group. Particularly early age of onset for essential blepharospasm might be an indicator of failure to respond to the injections.

Adult↗

PubMed1993

Polyphenotypic small-cell orbitocranial tumor.

A male infant was born with a massive orbitocranial tumor without evidence of metastasis. On light microscopy, the histologic pattern of the tumor was that of a largely necrotic and highly undifferentiated small round cell neoplasm of uncertain origin. Ultrastructural features of the primitive cells included a rare tight junction and myofibril. Immunohistochemical studies showed positive staining for cytokeratin, vimentin, muscle-specific actin, neuron-specific enolase, and S100 protein and negativity for desmin and leukocyte common antigen. We believe this case represents an example of a polyphenotypic small-cell tumor of childhood with epithelial, rhabdomyoblastic, and neuroectodermal differentiation.

Humans↗

PubMed1993

Early revision in the office for adults after unsatisfactory blepharoptosis correction.

The most common complications of levator palpebrae superioris muscle blepharoptosis repair are undercorrection, overcorrection, and abnormalities of the eyelid contour. Previously described nonsurgical as well as surgical methods delay the repair of such complications and introduce the same confounding factors that can affect judgment of the eyelid level as during the initial surgical procedure. Twenty-two patients underwent a highly predictable surgical technique to revise unsatisfactory postoperative eyelid positions. Twenty-five of 26 eyelids (96%) had a satisfactory result and only one of 26 (4%) remained undercorrected. The revision is performed three to four days after the initial blepharoptosis correction and involves blunt separation of the wound without local anesthesia. The levator aponeurosis is advanced or recessed and resutured to the tarsus to achieve the proper eyelid height and contour. The advantages of this revision technique are as follows: (1) the procedure can be quickly and easily performed in the office; (2) the anatomic defects are corrected; (3) sharp dissection, bleeding, and edema are avoided; (4) the technique is painless and usually requires no local anesthetic injections; (5) the tone and function of the levator palpebrae superioris muscle, Müller's, and orbicularis oculi muscles remain undisturbed intraoperatively; and (6) early correction is achieved, thereby enhancing patient acceptance.

Adolescent↗

PubMed1993

Levator aponeurosis elastic fiber network.

This light and electron microscopic study demonstrates an elastic fiber network (EFN) for the levator palpebrae superioris muscle complex, which forms an intricate insertion into the upper eyelid. The EFN is examined in the monkey, in a fresh exenteration specimen, and in fresh frozen cadaver specimens from both sexes of different age groups. Multiple elastic insertions of the levator aponeurosis and Muller's muscle attachment with well-organized elastic fibers are demonstrated using special staining techniques and serial microscopic sectioning. Transmission electron microscopy (TEM) confirms the ultrastructure of "mature" elastin fibers in Muller's muscle tendon and their close relationship with the elastin-related fiber, oxytalan. Current thinking concerning the nature of elastic fibers and their possible implications in acquired involutional blepharoptosis is discussed. This microscopic study of the EFN of the upper eyelid focuses attention on the multiple elastic fiber insertions of the levator muscle complex that includes the levator aponeurosis, the conjoined fascia, the lid crease area, and Muller's muscle tendon, which have not been previously described.

Adult↗

PubMed1993

Monopolar electrocautery dissection in ophthalmic plastic surgery.

Monopolar electrocautery in the cutting mode is a superb surgical technique in many types of oculoplastic surgery because it efficiently dissects tissue with excellent hemostasis. The purpose of this article is to define how monopolar electrocautery functions and point out specific steps of certain oculoplastic procedures in which electrocautery dissection is useful. We have found it to be a helpful adjunct in over 1,200 clinical cases. We review the problems with electrocautery reported in the literature and discuss ways to avoid them.

Blepharoptosis↗

PubMed1993

Unilateral ptosis and eye dominance.

We studied the relationship between eye dominance (Scobee test) and upper lid level (MRD) in 54 patients with unilateral ptosis or asymmetric bilateral ptosis (> or = 2 mm difference in MRD) using the phenylephrine test. A contralateral lid drop was measured in 12/54 patients after instillation of 2.5% phenylephrine in the more ptotic eye and occurred in both congenital (3) and acquired (9) ptosis cases. A contralateral lid drop was seen in 7/14 (50%) patients whose ptosis was greater in the dominant eye and in 5/40 (12.5%) patients whose ptosis was greater in the nondominant eye (p = .01). Contralateral lid drops > or = 1 mm were present in 7/54 patients, and 6/14 (43%) of them had greater ptosis on the dominant side and 1/40 (2.5%) on the non-dominant side (p = .001). There was no association between contralateral pseudoretraction and either visual acuity or severity of ptosis. These results suggest that levator muscle tone is influenced by eye dominance when ptosis is present. The preoperative evaluation of unilateral or asymmetrical bilateral ptosis cases should include the Scobee and phenylephrine tests to unmask contralateral upper lid pseudoretraction.

Adolescent↗

PubMed1993

Identification of orbital lymphatics: enzyme histochemical light microscopic and electron microscopic studies.

The presence of orbital lymphatics in the primate model is demonstrated using light and electron microscopic enzyme histochemistry. In addition, strictly morphological definitions of lymphatics, such as discontinuous basal lamina, thin and irregular walls, anchoring filaments, and attenuated endothelial cell cytoplasm, were applied. This study confirmed the presence of conjunctival lymphatics reported by others. It also clearly demonstrated the presence of orbital arachnoid and lacrimal gland lymphatics that have not been previously described. A few areas of the extraocular muscles and connective tissue at the orbital apex also showed evidence of the presence of lymphatic vessels. Additional work is needed to define the nature and extent of orbital lymphatics as well as their connection to the extraorbital lymphatic system.

Adipose Tissue↗

PubMed1993

Temporary sutured tube-tarsorrhaphy: reversible eyelid closure technique.

Temporary closure of the eyelids is frequently recommended for ocular surface disorders in which reepithelialization of the cornea is problematic, as well as for acute Bell's palsy. We describe an easily performed technique of temporary tarsorrhaphy using plastic tubes sutured externally to the upper and lower eyelids, with eyelid closure accomplished by tightening a loop of suture passed through the two tubes. Corneal epithelial defects in 11 of 13 patients in whom we used this technique resolved satisfactorily without complications. In the remaining two, the polypropylene sutures eroded through the eyelids between 5 and 6 weeks after surgery. The sutured tubes loosened and the loosened sutures had to be replaced. In one patient, the overly long end of a suture rotated between the apposed eyelids, inducing a corneal abrasion, but no permanent damage to the eye. We conclude that the sutured tube-tarsorrhaphy provides excellent short-term closure of the eyelids, while allowing simple, painless opening for examining the globe. The risks of inflammation and infection associated with previously described techniques are minimized.

Corneal Diseases↗

PubMed1992

Sympathetic nerve anatomy in the cavernous sinus and retrobulbar orbit of the cynomolgus monkey.

We present new information regarding the sympathetic nerve anatomy in the cavernous sinus and retrobulbar orbit of the cynomolgus monkey. Postganglionic sympathetic nerves were identified using an immunoperoxidase technique in which the primary antiserum was directed against tyrosine hydroxylase, the rate-limiting enzyme in norepinephrine synthesis. Our work is unique in adapting this staining method to paraffin-embedded tissue. This technique allows sympathetic nerve fibers to be distinguished from other autonomic, sensory, and motor nerves. A large sympathetic nerve bundle lateral to the internal carotid artery in the cavernous sinus gave off one or more branches that leave the artery to encircle the abducens nerve. Further division occurs within the cavernous sinus, but all sympathetic nerve fibers destined for the orbit entered it through the superior orbital fissure. None pass through the optic canal. In the orbit, sympathetics were associated with the ophthalmic artery and some of its branches and with the sensory root to the ciliary ganglion. After entering the ganglion, the sympathetic fibers were lost to detection in most specimens, but they were again seen in a single short ciliary nerve in one instance. Sympathetic nerve fibers were not detected adjacent to several structures identified in the human anatomy literature, such as the intracranial and intracanalicular segments of the ophthalmic artery, the nasociliary nerve, the long ciliary nerves, the nerve to the inferior oblique muscle, or the lacrimal artery and nerve.

Animals↗

PubMed1991

Problems associated with conjunctivodacryocystorhinostomy.

Fifty-eight patients (69 eyes) underwent conjunctivodacryocystorhinostomy for lacrimal canalicular obstruction. The cause of lacrimal obstruction and the results and complications of the operation were analyzed. Trauma and idiopathic disease were the most common causes of lacrimal canalicular obstruction in 24 of 69 (34.8%) eyes each. Relief of epiphora was achieved in 68 of the 69 eyes (98.5%). The complications included tube displacement in 40 of the 69 eyes (57.9%), tube obstruction in 19 of the 69 eyes (27.5%), and infection of the lacrimal sac in four of the 69 eyes (5.8%). Despite frequent complications, most Jones tubes can be made to function satisfactorily. Conjunctivodacryocystorhinostomy remains the best surgical treatment at this time for permanent loss of canalicular function.

Adolescent↗

PubMed1991

Canalicular stenosis following probing for congenital nasolacrimal duct obstruction.

A canalicular stenosis was identified in 29 of 66 (44%) children and 35 of 80 (44%) lacrimal drainage systems undergoing silicone intubation for congenital nasolacrimal duct obstruction, having previously had unsuccessful probings. The stenoses were equally divided between boys and girls and between right and left sides. There was no significant difference in age at the time of probing, number of prior probings, or age at intubation between children with and without canalicular stenosis. Stenoses may be congenital or acquired as a result of faulty probing. Any child undergoing a second lacrimal procedure after a failed probing should be evaluated for evidence of a canalicular stenosis. If a stenosis is present, a silicone stent should be placed to try to salvage the canaliculus.

Child, Preschool↗

PubMed1990

The pathophysiology of the anophthalmic socket. Part I. Analysis of orbital blood flow.

A wide variety of complications of the anophthalmic socket develop in patients after enucleation, including enophthalmos, superior sulcus deformities, eyelid malpositions, implant migration and extrusion, poor prosthetic motility, and socket contraction. Changes in the orbital blood flow and metabolic activity of the socket tissues and atrophy of the orbital fat occurring after enucleation have been suggested as two theoretical mechanisms that result in the development of these clinical conditions. Lack of scientific evidence and a limited understanding of the pathophysiologic basis of the features of anophthalmos led us to evaluate the validity of these proposed mechanisms in an animal model. Selected parameters of the normal orbits were compared with the contralateral anophthalmic orbits at different time intervals after surgery. Orbital blood flow was studied with selective ophthalmic artery angiography and radioactive microsphere techniques. Ophthalmic arteriography demonstrated symmetric caliber and filling characteristics of the major orbital vessels of the control and experimental orbits, although their topographic course was slightly more tortuous in the anophthalmic socket. Results of radioactive microsphere analysis of capillary blood flow per weight of the different orbital tissue compartments of the animals in the long-term group showed no significant difference between the normal and anophthalmic sockets. These findings provide evidence that the circulation dynamics and blood flow to orbital tissues do not change after enucleation surgery.

Angiography↗

PubMed1990

The pathophysiology of the anophthalmic socket. Part II. Analysis of orbital fat.

The pathophysiologic mechanisms responsible for the clinical features of the anophthalmic socket are poorly understood. Atrophy of orbital fat has been thought to be a major contributing cause of enophthalmos and the superior sulcus deformities that develop after enucleation, but it has never been demonstrated histopathologically or confirmed by scientific analysis. This study was undertaken to investigate the changes that occur in the orbital fat compartment of the anophthalmic socket in an animal model by measuring orbital soft tissue mass and evaluating adipocyte cell size. Instead of reduction in the tissue mass, a statistically significant greater weight of the fat and connective tissue compartment was found in the anophthalmic orbit by nearly 13% compared to the control orbit in the animals in the long-term group. No significant change in the mean maximal diameter of adipocytes developed 7 months after enucleation. These analyses do not support the concept that orbital fat atrophy or a reduction of metabolic activity occurs in the anophthalmic socket in this animal model. From these results and our previous findings that the circulation dynamics and blood flow to orbital tissues do not change after enucleation, we propose that the pathophysiologic basis of the problems associated with anophthalmos is a disturbance in the spatial architecture and interrelationships of the multiple tissue components of the orbit, not a change in the orbital blood flow or development of fat atrophy.

Adipose Tissue↗

PubMed1989

A search for lymphatic drainage of the monkey orbit.

Colloid solutions of technetium Tc 99m and india ink injected into the retrobulbar space of the cynomolgus monkey outside the extraocular muscle cone were removed from the orbit by the lymphatic vessels of the conjunctiva and eyelids and were then concentrated within the lymph nodes that drained the conjunctival and eyelid areas. Colloid solutions injected into the retrobulbar space inside the extraocular muscle cone did not reach the conjunctiva and did not collect in any lymph nodes over a 24-hour period. Within the orbit, the injected colloids spread along the planes of the connective-tissue septa. No lymphatic vessels were identified within the orbits posterior to the conjunctiva. Small amounts of india ink left the posterior orbit and ultimately entered the contralateral orbit. This posterior pathway did not lead to lymphatic vessels or lymph nodes and therefore does not appear to represent a prelymphatic pathway.

Animals↗

PubMed1989

Medial orbital wall fractures: complications and management.

Medial wall fractures are often overlooked during routine radiographic examination and rarely develop complications. We present complications associated with medial wall fracture in six cases. Complications from medial rectus muscle entrapment include restricted and painful abduction, pseudo-sixth-nerve paresis and pseudo-Duane's-retraction syndrome. Massive orbital emphysema, in one case, was responsible for temporary loss of vision prior to definitive treatment. Two patients developed severe enophthalmos secondary to the medial wall fractures. We suggest that orbital exploration is indicated for painful or limited ocular motility, significant diplopia, severe orbital emphysema, or severe enophthalmos. An inferior approach to the medial wall through the lower eyelid provides good exposure and minimal cosmetic deformity. Postoperative complications included transient paresis of the medial rectus muscle, residual motility disturbance, and residual enophthalmos.

Adolescent↗

PubMed1989

Magnetic resonance imaging of the orbit. Part I. Physical principles.

Magnetic resonance has twin capabilities. It can provide anatomical (magnetic resonance imaging, MRI) and physiochemical (magnetic resonance spectroscopy) information. Nuclei with an odd mass number, particularly hydrogen in free water, have electromagnetic properties. When placed in a strong static magnetic field and excited by radiofrequency waves of a specific wavelength, these nuclei emit a signal. The MR signal can then be digitized, stored in a computer, and subsequently converted into an image. Factors that affect these images are tissue parameters (T1 and T2 time constants, proton density, and flow) and radiofrequency pulse sequences. Surface coils are useful for improving images of the orbit. The magnet can have a major and potentially dangerous influence on the surrounding environment, and access to the MRI area must be carefully controlled. Shielding of the MRI room prevents external factors from adversely affecting the MRI unit and the images produced.

Equipment Design↗