Bilateral periopticointrascleral hemorrhages associated with traumatic child abuse

PURPOSE

To report a case of bilateral periopticoscleral hemorrhages associated with traumatic child abuse.

METHODS

Postmortem gross examination and histopathologic studies of both eyes and the optic nerves of a 6-month-old infant who died from subdural hematoma.

RESULTS

Gross examination and histopathologic step sections disclosed bilateral intrascleral hemorrhages around both optic nerves. In addition, bilateral diffuse multilayered retinal, vitreous, and sublaminar (beneath the internal limiting membrane) hemorrhages were present.

CONCLUSION

Periopticointrascleral hemorrhages are characteristic of blunt head trauma and may constitute important forensic evidence in cases of suspected child abuse.

Lipophilins: human peptides homologous to rat prostatein

Lipophilin components A, B and C are human homologues of prostatein, the major secreted protein of rat prostate. This report describes their cDNA sequences, tissue expression and chromosomal localization. Lipophilin gene products were widely expressed in normal tissues, especially in endocrine-responsive organs. The gene for lipophilin C (also called mammaglobin b) is located on chromosome 11q12-q13.1, near the mammaglobin gene, a homologue overexpressed in many breast cancers. The lipophilin B gene resides on chromosome 10q23, a region deleted in many tumors, and the lipophilin A gene is on chromosome 15q12-q13.

Fine-needle aspiration: comparison of smear, cytospin, and cell block preparations in diagnostic and cost effectiveness

We compared the results of smears to those of cytospin and cell block preparations from fine-needle aspirations to determine the cost effectiveness of each and to determine which should be routinely obtained. We reviewed 844 cases, 361 of which had both smears and cytospins, and 483 of which had both smears and cell blocks. Smears alone were diagnostic in 94% of cases (796/844 cases), cytospins alone diagnostic in 43% of cases (154/361 cases), and cell blocks alone diagnostic in 57% of cases (277/483 cases). Cytospins contributed additional information beyond that obtained from smears in 2% (7/361) and cell blocks in 12% (57/483) of cases. When smears were nondiagnostic, cytospins contributed additional information in 10% (2/21) of cases and cell blocks contributed additional information in 44% (12/27) of cases. The cost of providing a diagnosis from smear alone is $212, from cytospin alone is $352, and from cell block alone is $392. The cost for additional information established by cytospin is $7,736 and by cell block the cost is $1,906. Smears are superior to either cytospins or cell blocks in providing a diagnosis. It is not cost-effective to obtain either cytospins or cell blocks in addition to smears on all cases. However, it is cost-effective to obtain cell blocks when the immediate smear evaluation is nondiagnostic.

Nonvascular contractile cells in sclera and choroid of humans and monkeys

PURPOSE

To investigate by histochemistry and immunohistochemistry the distribution and innervation of nonvascular contractile cells in the sclera and choroid of humans and monkeys.

METHODS

Globes were obtained from 2 macaque monkeys and 19 human cadavers that ranged in age from fetal life to 94 years. Immunohistochemistry was performed using monoclonal antibody against human smooth muscle (SM) alpha-actin and tyrosine hydroxylase (TH). The nicotinamide-adenine dinucleotide phosphate (NADPH)- diaphorase reaction was used as a marker for nitric oxide synthase.

RESULTS

The scleras of all but fetal, newborn, and infant globes exhibited myofibroblasts, amelanotic, fibroblastlike cells having SM alpha-actin immunoreactivity. In the choroid of all but fetal eyes, SM cells were present in the suprachoroidal layer, forming a reticulum of flattened laminae, and in the choriocapillaris where ovoid-to-spindle-shaped SM cells were arrayed in parallel layers immediately adjacent to Bruch's membrane. Contractile cells in the sclera and choroid were most concentrated subfoveally and were sparse anteriorly. Nerve terminals positive for NADPH- diaphorase were colocalized with SM alpha-actin-positive cells in the sclera and choroid, whereas TH-positive nerve terminals colocalized with SM cells in the choroid. Clusters of ganglion cells were present on the posterior surface of globes near SM cells.

CONCLUSIONS

The posterior choroid and sclera of humans and monkeys contain nonvascular contractile cells. The presence of nerve terminals and adjacent ganglion cells suggests neural control of these contractile cells. The absence of such contractile cells in fetal, newborn, and infant eyes is an argument against a major role of these cells in promoting ocular enlargement. These contractile cells may instead participate in regulation of refractive state by maintenance of ocular size in the face of intraocular pressure or in intermediate-term regulation of choroidal thickness.

Lipophilin, a novel heterodimeric protein of human tears

We identified a novel heterodimeric protein, lipophilin AC, in human tears. One of its components, lipophilin A (69 residues; mass, 7575.1; pI, 9.47) was homologous to the C1 and C2 components of prostatein ('estramustine-binding protein'), the major secreted protein of rat prostate. Human lipophilin C (77 residues; mass, 8854.1; pI, 4.94) was homologous to the rat prostatein C3 component and to human mammaglobin, a protein overexpressed in some mammary carcinomas. Tear lipophilins A and C expand the roster of human uteroglobin superfamily members and provide models for exploring these typically steroid-regulated and steroid-binding molecules.

Structural changes in human tear lipocalins associated with lipid binding

Structural and conformational changes in tear lipocalins were detected in association with ligand binding and release. Circular dichroism measurements demonstrated that ligand binding induces beta structure formation, aromatic side chain asymmetry, and a more rigid state in tear lipocalins (TL). The exposure of the tyrosyl component is less in apo-TL than in holo-TL. The sole tryptophan residue, Trp17, is buried in both holo- and apo-TL. The steady state exposure of Trp17 is the same in holo- and apo-TL, but the dynamic exposure is two-fold greater in apo-TL. Maneuvers to unfold the protein with urea or incubation in an acidic environment resulted in increased exposure of aromatic amino acids. Electron paramagnetic resonance studies verified that lipids are liberated from TL in an acidic environment. Acidic pH promotes conformational changes in TL involving aromatic residues, particularly the conserved residue Trp17. These changes are associated with lipid release. The liberation of lipid from the cavity of TL under acidic conditions involves a molten globule state of the protein. We postulate that TL, exposed to the steep surface pH gradient that exists at lipid-aqueous interfaces, would release lipid in association with a molten globule transition. The data suggest a plausible regulatory mechanism for lipid delivery from lipocalins at the tear film surface.

Fine-needle aspiration: comparison of smear, cytospin, and cell block preparations in diagnostic and cost effectiveness

We compared the results of smears to those of cytospin and cell block preparations from fine-needle aspirations to determine the cost effectiveness of each and to determine which should be routinely obtained. We reviewed 844 cases, 361 of which had both smears and cytospins, and 483 of which had both smears and cell blocks. Smears alone were diagnostic in 94% of cases (796/844 cases), cytospins alone diagnostic in 43% of cases (154/361 cases), and cell blocks alone diagnostic in 57% of cases (277/483 cases). Cytospins contributed additional information beyond that obtained from smears in 2% (7/361) and cell blocks in 12% (57/483) of cases. When smears were nondiagnostic, cytospins contributed additional information in 10% (2/21) of cases and cell blocks contributed additional information in 44% (12/27) of cases. The cost of providing a diagnosis from smear alone is $212, from cytospin alone is $352, and from cell block alone is $392. The cost for additional information established by cytospin is $7,736 and by cell block the cost is $1,906. Smears are superior to either cytospins or cell blocks in providing a diagnosis. It is not cost-effective to obtain either cytospins or cell blocks in addition to smears on all cases. However, it is cost-effective to obtain cell blocks when the immediate smear evaluation is nondiagnostic.

Carcinoma of the male breast metastatic to both orbits

We report the case of a 43-year-old man who presented with painless proptosis of the right eye of 6 weeks' duration. Examination demonstrated a tense right orbit and decreased vision and extraocular motility bilaterally. Diagnostic evaluation included computed tomographic imaging of the head and orbits, a therapeutic trial of high-dose systemic corticosteroids, and orbital biopsy, which revealed the presence of metastatic adenocarcinoma. The primary tumor was found to be an estrogen-receptor-positive, infiltrating ductal adenocarcinoma of the right breast. Therapy included lumpectomy of the breast mass, orbital irradiation, and hormonal therapy. Metastatic carcinoma of the breast should be considered in the differential diagnosis of orbital neoplastic disease in the male patient.

A conserved disulfide motif in human tear lipocalins influences ligand binding

Structural and functional characteristics of the disulfide motif have been determined for tear lipocalins, members of a novel group of proteins that carry lipids. Amino acid sequences for two of the six isolated isoforms were assigned by a comparison of molecular mass measurements with masses calculated from the cDNA-predicted protein sequence and available N-terminal protein sequence data. A third isoform was tentatively sequence assigned using the same criteria. The most abundant isoform has a measured mass of 17 446.3 Da, consistent with residues 19-176 of the putative precursor (calculated mass 17 445.8 Da). Chemical derivatization of native and reduced/denatured protein confirmed the presence of a single intramolecular disulfide bond in the native protein. Reactivity of native, reduced, and denatured protein with 4-pyridine disulfide and dithiobis(2-nitrobenzoic acid) indicated that access to the free cysteine is markedly restricted by the intact disulfide bridge. Mass measurements of tryptic fragments identified C119 as the free cysteine and showed that the single intramolecular disulfide bond joined residues C79 and C171. Circular dichroism indicated that tear lipocalins have a predominant beta-pleated sheet structure (44%) that is essentially retained after reduction of the disulfide bond. Circular dichroism in the far-UV showed reduced molecular asymmetry and enhanced urea-induced unfolding with disulfide reduction indicative of relaxation of protein structure. Circular dichroism in the near-UV shows that the disulfide bond contributes to the asymmetry of aromatic sites. The effect of disulfide reduction on ligand binding was monitored using the intrinsic optical activity of bound retinol. The intact disulfide bond diminishes the affinity of tear lipocalins for retinol and restricts the displacement of native lipids by retinol. Disulfide reduction is accompanied by a dramatic alteration in ligand-induced conformational changes that involves aromatic residues. The disulfide bridge in tear lipocalins is important in conferring protein rigidity and influencing ligand affinity. The disulfide bond appears highly conserved so that these findings may have implications for the entire lipocalin superfamily.

Solution structure by site directed tryptophan fluorescence in tear lipocalin

The solution structure of the G strand of human tear lipocalin was deduced by site directed tryptophan fluorescence (SDTF). The fluorescent amino acid, tryptophan, was sequentially substituted for each native amino acid in the sequence of the G strand. The fluorescent properties resolved alternating periodicity as predicted for beta sheet structure, twists in the beta sheet, strand orientation in the lipocalin cavity, and the relative depth of residues in the cavity. A distribution of microstates with various orientations of dipoles in the side chain environments of the G strand revealed mobility on the nanosecond time scale. SDTF is broadly applicable to most proteins and will complement x-ray crystallography, site directed spin labeling by electron paramagnetic resonance (EPR), and nuclear magnetic resonance (NMR) in the determination of solution structure.

Epibulbar hemangiopericytoma

PURPOSE

To report a case of an epibulbar hemangiopericytoma that appeared clinically as a firm nodule.

METHODS

We examined a 28-year-old man with a 5-year history of a gradually enlarging red, firm epibulbar nodule. Excisional biopsy was performed.

RESULTS

Histopathology identified an encapsulated hemangiopericytoma. Eight-year follow-up showed no recurrence postresection.

CONCLUSIONS

Epibulbar hemangiopericytoma is rare and has a good prognosis after resection. The smaller size and more conspicuous location of epibulbar hemangiopericytomas may lead to relatively early treatment and account for a more favorable prognosis.

Intramammary lymph nodes: cytologic findings and implications for fine-needle aspiration cytology diagnosis of breast nodules

The recognition of intramammary lymphoid proliferations is important because smears of these proliferations would be judged as insufficient by several of the published criteria for specimen adequacy. Alternatively, some might be confused with medullary carcinoma of the breast or adenocarcinomas with a "single-cell" pattern. We found 19 intramammary lymphoid proliferations in a series of 887 fine-needle aspirates of palpable breast nodules. Six were lymphomas and 13 were benign intramammary lymph nodes. Smear cellularity ranged from scant to high, but in all cases, lymphocytes dominated the cell population. The cytology of intramammary lymph nodes and lymphoma did not differ from those occurring at other sites.

Salivary gland lesions with a prominent lymphoid component: cytologic findings and differential diagnosis by fine-needle aspiration biopsy

Fine-needle aspiration (FNA) is an accepted technique for the preoperative diagnosis of salivary gland nodules. The majority of salivary gland nodules are pleomorphic adenomas and offer little difficulty in diagnosis. Most diagnostically difficult lesions fall into one of four morphologic categories represented by squamous-cell-containing lesions, clear cell neoplasms, neoplasms with a prominence of stromal material, and lymphocyte-containing lesions. Herein, we describe our experience with a series of 61 histologically confirmed cases in which the smears contained a prominent or predominant number of lymphocytes. The differential diagnosis is discussed and points of diagnostic aid enumerated.

Evidence for breaches of the retinal vasculature in acquired immune deficiency syndrome angiopathy. A fluorescent microsphere study

PURPOSE

The author studied the retinal vasculature in patients with acquired immune deficiency syndrome (AIDS) by infusion of microspheres impregnated with fluorescent dye.

METHODS

Experimental study of the structural integrity of the retinal microvasculature in 14 autopsy patients with AIDS was compared with age- and gender-matched control retinas.

MATERIALS

Fourteen autopsy eyes from patients with AIDS, eight autopsy eyes from immunosuppressed control patients, and four autopsy eyes from nonimmunosuppressed control patients were studied.

EXPERIMENTAL METHOD

The central retinal arteries of autopsy eyes were perfused with fluorescent microspheres of 10 and 200 nm in diameter. The retinas were dissected from the eyes and viewed by fluorescence microscopy.

RESULTS

Vascular breaches permeable to 200-nm microspheres were discovered in eyes from patients with AIDS. Ruptured microaneurysms were identified at the center of retinal hemorrhages in 7 of 14 eyes from patients with AIDS and 5 of 8 immunosuppressed control eyes. Leakage around microaneurysms occurred even in the absence of hemorrhage and were more frequent in eyes from patients with AIDS (11/14) than in control eyes (3/12). Cotton wool patches were surrounded by tortuous retinal vessels and microaneurysms.

CONCLUSIONS

Ruptured microaneurysms are a frequent cause of retinal hemorrhage in immunosuppressed patients. Breaches in microaneurysms occur even in the absence of hemorrhage. These breaches are often at least 200 nm in diameter, a size that is permissive to capsids and virions of cytomegalovirus (CMV). Ruptured and/or leaky microaneurysms are potential sources of CMV permeation of the blood-retinal barrier. Breaches of the retinal microvasculature are not specific to patients with AIDS and occur frequently in other immunosuppressed patients.

Cavitation in ciliary body melanoma

PURPOSE

To report a case of a cystic ciliary body melanoma that appeared clinically as a solid mass.

METHODS

A 59-year-old woman underwent an iridocyclectomy for removal of a ciliary body melanoma in the right eye. The tumor was analyzed histopathologically for acid mucopolysaccharide production.

RESULTS

Histopathology identified a ciliary body melanoma with cystic cavities. Contents of the cystic spaces did not stain with alcian blue. Histologic findings suggested exudation, cavitary necrosis, or both rather than acid mucopolysaccharide production as pathogenic factors for cyst formation.

CONCLUSION

Cystic cavities can develop in a solid, malignant tumor and therefore should not be considered signs of a benign lesion.

Chiasmal infarction and sudden blindness caused by mucormycosis in AIDS and diabetes mellitus

PURPOSE

To report rapidly progressive rhino-orbitocerebral mucormycosis in a 47-year-old woman with both diabetes mellitus and the acquired immunodeficiency syndrome (AIDS).

METHOD

Case report including postmortem examination of the eyes, orbit, and brain of a patient with rhino-orbitocerebral mucormycosis, diabetes mellitus, and AIDS.

RESULTS

Invasion by hyphae of the Rhizopus species produced an occlusive vasculitis and massive infarction of the optic chiasm. Fungal organisms were discovered in multiple granulomata of the optic nerve.

CONCLUSION

Infarction at the optic chiasm probably caused sudden blindness in this patient.

Bilateral endogenous Fusarium endophthalmitis associated with acquired immunodeficiency syndrome

A 51-year-old man with acquired immunodeficiency syndrome and cytomegalovirus retinitis had bilateral endogenous fungal endophthalmitis. Cultures yielded Fusarium species. Histopathologic examination showed a severe necrotizing acute and granulomatous reaction, with numerous fungal elements in the retina and uveal tract. Fungal elements were seen in the lens, sclera, and emissarial vessels. Angiopathic infiltration by fungus and widespread thrombosis produced retinal and choroidal infarction. In some areas, fungal infection coexisted with cytomegalovirus retinitis. The bilateral distribution suggests hematogenous seeding of the eyes. The eye findings were the first clinically apparent manifestations of fungal disease in this patient.

Draining cutaneous fistula associated with infection of hydroxyapatite orbital implant

The implantation of an orbital hydroxyapatite implant was complicated by conjunctival dehiscence, cutaneous fistula formation, and infection with Staphylococcus aureus. Pathologic examination of the sphere 2 years after its implantation revealed reduction in the size of the implant, peripheral lamellar bone formation and central necrosis. This is the first report of this constellation of complications with hydroxyapatite spheres positioned in the orbit. The 2-year interval between implantation and removal of the sphere is the longest reported in a case with histopathologic analysis.

Contact and noncontact transscleral neodymium:YAG laser cyclophotocoagulation in a rabbit model

PURPOSE

Contact versus noncontact transscleral neodymium:YAG laser cyclophotocoagulation was compared in a rabbit model with respect to the effects on intraocular pressure and pathologic findings.

METHODS

Thirty-two rabbits received comparable energy levels (2 joules) of contact and noncontact cyclophotocoagulation. Pneumotonometry was performed every other day following treatment.

RESULTS

For both the 2-week and 8-week periods following treatment, intraocular pressure was significantly lower in eyes receiving contact cyclophotocoagulation than in eyes receiving noncontact cyclophotocoagulation (for the 2-week period, mean difference in intraocular pressure was 5.3 mm Hg, n = 22, p < 0.001; for the 8-week period, mean difference in intraocular pressure was 4.3 mm Hg, n = 17, p < 0.013). Pathologic findings include acute ciliary body hemorrhage and inflammation (1 day), chronic inflammation (1 week), granulation tissue within laser lesions (2 weeks), and marked ciliary body atrophy (8 weeks).

CONCLUSIONS

In our rabbit model, contact cyclophotocoagulation was more effective in lowering intraocular pressure than noncontact cyclophotocoagulation. Both contact and noncontact cyclophotocoagulation produced a variety of pathologic lesions in the rabbit eye, including cataract, phthisis bulbi, and anterior synechiae.

Aspergillus endophthalmitis. An unrecognized endemic disease in orthotopic liver transplantation

PURPOSE

The authors discovered an unusually high incidence of Aspergillus endophthalmitis in an autopsy series of orthotopic liver transplantation recipients. This study was conducted to discern the frequency, topographic distribution, and potential significance of the infections.

METHODS

Autopsy reports from liver transplant patients were reviewed. All patients with Aspergillus endophthalmitis were studied by gross and histologic examination. Histologic sections were stained with Grocott-Gomori methenamine-silver nitrate and periodic acid-Schiff stains. Some Grocott-Gomori methenamine-silver nitrate stained sections were counterstained with hematoxylin-eosin. The distribution of ocular infections in the eye was determined for each patient. The organs infected were determined at autopsy.

RESULTS

The authors found seven patients with Aspergillus endophthalmitis. Six of these seven patients were from a group of 85 (7.1%) orthotopic liver transplantation recipients. Fourteen (16.5%) orthotopic liver transplantation recipients had invasive pulmonary aspergillosis and ten (11.8%) had disseminated disease. The eyes were the second most common site of infection. Two patients had ocular involvement as the only nonpulmonary site of infection. Aspergillus endophthalmitis was diagnosed in only one patient before death. Infection was located posterior to the equator in all patients; three patients were anterior to the equator as well. The retina (5/7), vitreous (5/7), and choroid (3/7) were common sites of infection.

CONCLUSIONS

This is the first report of Aspergillus endophthalmitis associated with orthotopic liver transplantation recipients. Patients with orthotopic liver transplants are unusually susceptible to invasive aspergillosis and Aspergillus endophthalmitis. Aspergillus infection is frequently bilateral, begins posteriorly in the retina or choroid, and has vitreous involvement. Recognition of this entity is important because many patients die of disseminated Aspergillus infection that may be detected early with bedside funduscopic examination.

Corneal scarring after photorefractive keratectomy in a penetrating keratoplasty

PURPOSE

To report severe scarring in a corneal graft after excimer laser photorefractive keratectomy.

METHODS

A 35-year-old man underwent photorefractive keratectomy twice for severe compound myopic astigmatism and anisometropia after penetrating keratoplasty.

RESULTS

Corneal opacity corresponded to areas of irregular epithelial thickness, focal absence of the basement membrane, loss of Bowman's layer, and stromal scarring in the ablation zone.

CONCLUSION

There may be an increased risk of severe corneal stromal scarring from photorefractive keratectomy in eyes that have had previous penetrating keratoplasty.

Immunopathologic features of Staphylococcus aureus endophthalmitis in the rat

PURPOSE

To study the clinical, histopathologic, and immunologic responses to Staphylococcus aureus endophthalmitis in rats.

METHODS

Experimental Lewis rats received an intravitreal injection of viable S. aureus (65 organisms), and control rats received sterile saline. The clinical scores, cellular infiltrate, delayed hypersensitivity reaction in skin tests, and serum and vitreous enzyme-linked immunosorbent assay titers of immunoglobulin (Ig) M, IgG, and IgA to ribitol teichoic acid (RTA), the major antigenic determinant of S. aureus cell wall, were measured and compared on days 3, 7, 10, 14, 21, and 30. The differences were statistically assessed using Mann-Whitney nonparametric t-tests and analysis of variance.

RESULTS

The red reflex was abolished in the majority of rats between days 3 and 21. Ocular inflammation resolved by day 30. The vitreous of eyes injected with S. aureus showed bacterial growth on days 3 and 7, followed by a decrease in numbers on days 10 and 14 and disappearance on days 21 and 30. In the vitreous, a peak neutrophil count was observed at day 3 that rapidly declined by day 7. The number of lymphocytes and plasma cells peaked on day 3 but declined more slowly. Plasma cells and Mott cells were seen on days 10 and 14, suggesting intraocular antibody production. IgM titers to RTA increased progressively in serum and vitreous, reached a peak on day 21, and declined on day 30. A weak IgG but absent IgA response to RTA was observed in serum and vitreous. S. aureus endophthalmitis was not associated with delayed hypersensitivity to the bacteria in skin tests.

CONCLUSIONS

S. aureus endophthalmitis is associated with the infiltration of neutrophils, lymphocytes, monocytes, and plasma cells in vitreous. Neutrophils, the predominant infiltrating cells, may be involved in bactericidal activity and opsonophagocytosis. In rat staphylococcal endophthalmitis, IgM rather than IgG may be the protective antibody.

Tissue expression of lipocalins in human lacrimal and von Ebner's glands: colocalization with lysozyme

BACKGROUND

Tear-specific prealbumin is a group of proteins recently renamed as the tear lipocalins. These proteins were initially described as unique to lacrimal fluid. The tissue distribution and localization have never been thoroughly studied.

METHODS

The distribution of purified tear lipocalins was studied in many human secretions and tissues by western blots, immunohistochemistry and immunoelectron microscopy.

RESULTS

Tear lipocalin species of the same molecular weights were observed in western blot lanes loaded with tears, saliva, and protein extracts from the lacrimal and lingual von Ebner's glands. Lacrimal and von Ebner's glands contained tear lipocalins; other human tissues and secretions, including other salivary glands and taste buds, did not. Tear lipocalins colocalized with lysozyme in serous acinar cells of lacrimal and von Ebner's glands. Ultrastructurally, tear lipocalins were present on polyribosomes, endoplasmic reticulum, and Golgi areas. Lipocalins were concentrated in lacrimal secretory granules in amounts commensurate with a regulated pathway.

CONCLUSION

Tear lipocalins are expressed and truncated similarly in lingual von Ebner's and lacrimal glands, but not at all in other human tissues. Lipocalins are expressed and secreted with lysozyme. Lipocalins are concentrated in secretory granules in an amount consistent with a regulated secretory pathway.

Rupture of radial and arcuate keratotomy scars by blunt trauma 91 months after incisional keratotomy

PURPOSE/METHODS

We studied a case in which blunt trauma caused dehiscence of radial and arcuate corneal scars 91 months after incisional keratotomy. The ruptured incisions did not extend beyond the corneoscleral limbus.

RESULTS/CONCLUSIONS

Incisional refractive surgery renders the cornea susceptible to blunt traumatic rupture. This vulnerability results from the intrinsic weakness of the keratotomy wounds. Our case documents that this weakness persists up to 91 months after the operation.

Vortex vein exit sites. Scleral coordinates

PURPOSE

The authors determined the frequency and scleral coordinates of vortex vein exit sites in 46 autopsy eyes to provide topographic data that will enable surgeons to locate these vessels more precisely.

METHODS

Forty-six autopsy eyes were examined under a dissecting microscope to measure the frequency of vortex veins and the cord lengths between the vortex vein scleral exit sites and the limbus, rectus muscle insertions, and oblique muscle insertions.

RESULTS

Data from this study showed that 32 (70%) of the 46 individual eyes studied had more than four vortex veins. The number of second or third vortex veins found in the nasal quadrants was significantly higher than the number found in the temporal quadrants (P < 0.01). Statistical analyses of the measurements provided mean values for distances between vortex vein scleral exit sites and the three nearest extraocular muscle insertions; these positions among eyes were found to be relatively uniform (standard deviation, 0.7-2.5 mm).

CONCLUSION

The authors suggest that the majority of adult eyes encountered by a surgeon will have more than four vortex vein exit sites and that more vortex veins may be expected in the nasal quadrants than in the temporal quadrants. This study delineates the locations of vortex vein exit sites so that surgeons can reliably predict their surface positions to avoid vessel laceration and its ensuing complications.

Evidence for fibromuscular pulleys of the recti extraocular muscles

PURPOSE

Magnetic resonance imaging (MRI) shows that the paths of recti extraocular muscle (EOM) bellies remain fixed in the orbit during large ocular rotations and across large surgical transpositions of their insertions. These findings imply that recti EOMs pass through pulleys coupled to the orbit and anterior to the muscle bellies, because the insertions must move with the globe. The present study was conducted to locate anatomically and to characterize histologically the pulley tissues.

METHODS

High-resolution MRI images were collected from volunteers, using multiple gaze directions to infer the locations of, and occasionally to visualize, recti EOM pulleys. Fresh cadaver orbits were exenterated and dissected to evaluate mechanical and structural properties of the orbital connective tissues. Lipid was cleared from whole specimens to reveal tissue relationships. Other specimens were selectively step- and serial-sectioned for histochemical and immunohistochemical staining.

RESULTS

Magnetic resonance imaging demonstrated dense connective tissue structures within posterior Tenon's fascia near the equator of the globe adjacent to the recti EOMs. Histochemistry showed these structures to be pulleys--fibroelastic EOM sleeves consisting of dense bands of collagen and elastin, suspended from the orbit and adjacent EOM sleeves by bands of similar composition. A monoclonal antibody to human smooth muscle alpha-actin demonstrated substantial smooth muscle in the pulley suspensions and in posterior Tenon's fascia. Tenon's fascia itself was seen to be suspended at its periphery from the orbital walls like a drumhead.

CONCLUSIONS

The human orbit contains specialized musculofibroelastic tissues in and just posterior to Tenon's fascia that serve as compliant pulleys and determine the pulling directions of recti EOMs. In this sense, the pulleys are the functional origins of the recti EOMs and are determinants of ocular motility.

Tear lipocalins bind a broad array of lipid ligands

To identify the native ligands of tear lipocalins, tear proteins were separated by size exclusion chromatography and the lipid content in the major protein fractions identified. Lipids extracted from native tears and purified tear lipocalins comigrated with fatty acids, fatty alcohols, phospholipids, glycolipids, and cholesterol on thin layer chromatograms. Abundant stearic and palmitic acids as well as cholesterol, and lesser amounts of lauric acid were specifically identified in extracts of purified lipocalins by gas chromatography-mass spectroscopy. A preliminary study of the ligand-protein interaction was carried out using nitroxide spin-labeled lipids.

Cuterebra Ophthalmomyiasis

PURPOSE/METHODS

We used a simple laboratory method to identify the first instar stage of a Cuterebra larva that emerged from the conjunctiva of a 14-year-old boy with ipsilateral decreased vision, subretinal hemorrhages, and linear streaks in the fundus. The maggot was removed from the conjunctiva and cleared in glycerol solutions.

RESULTS/CONCLUSIONS

Light microscopy disclosed spines characteristic of Cuterebra larvae. Scanning electron microscopy is not necessary for diagnosis of Cuterebra ophthalmomyiasis even if samples are limited to the larval thorax.

A quantitative and cartographic study of retinal microvasculopathy in acquired immunodeficiency syndrome

We quantified the retinal microvascular abnormalities in 57 eyes from autopsy patients with the acquired immunodeficiency syndrome (AIDS) and in 24 eyes from gender- and age-matched control subjects. We related retinal vascular changes to the topography of cytomegalovirus retinitis. Analysis of retinal trypsin digests revealed more vascular attenuation (P = .005), increased ratio of endothelial cells to pericytes (P = .001), and more microaneurysms (P = .02) in eyes of AIDS patients without cytomegalovirus retinitis than in those of control subjects. Cytomegalovirus retinitis was frequently bilateral, extensive, and distributed along blood vessels. Peripheral retinitis was more frequent than macular infection. Lymphocytes aggregated focally in arterioles, venules, and capillaries leading to areas infected with cytomegalovirus. Acquired immunodeficiency syndrome microvasculopathy occurs in the absence of cytomegalovirus retinitis and is not accounted for by immunosuppression alone. The location and character of these vascular changes in AIDS indicate an ischemic pathogenesis. In AIDS patients with cytomegalovirus retinitis, the vascular changes are more profound and include capillary destruction.

Corneal ectasia as a complication of repeated keratotomy surgery

BACKGROUND

Staged keratotomy surgery, or "enhancement surgery," may allow a more predictable outcome, but also subjects the patient to additional surgical risks.

METHODS

A 39-year-old man underwent astigmatic keratotomy for myopic astigmatism, followed by 12 enhancement procedures for residual astigmatism.

RESULTS

These procedures effectively resulted in a double hexagonal keratotomy. The patient's best spectacle-corrected acuity deteriorated to counting fingers. Clinically, a conically-shaped protrusion of the central cornea, Munson's sign, diffuse subepithelial scarring, and central corneal thinning were noted. Penetrating keratoplasty was performed. Histopathologic examination showed central thinning, epithelial edema, disruption of Bowman's layer, marked stromal scarring, and focal areas of endothelial attenuation--findings consistent with keratoconus.

CONCLUSION

This case illustrates that multiple keratotomy procedures may result in corneal ectasia in apparently normal eyes and suggests that hexagonal keratotomy may be more likely to cause iatrogenic keratoconus.

GLUT1 glucose transporter expression in the diabetic and nondiabetic human eye

PURPOSE

The GLUT1 glucose transporter is expressed in endothelial and epithelial barriers, including the retinal capillary endothelium and the retinal pigment epithelium (RPE) of the eye. The present studies were undertaken to determine whether GLUT1 is expressed in additional cell types within the human eye and whether retinal endothelial GLUT1 is aberrantly expressed in diabetic proliferative retinopathy in humans.

METHODS

Immunohistochemical staining of sections of human eyes obtained at surgery or autopsy from patients with and without diabetes was performed with polyclonal antisera directed against the human GLUT1 glucose transporter.

RESULTS

In the course of this study, an unexpected multicellular localization of GLUT1 in different cellular barriers of the human eye was observed. In the nondiabetic eye, specific staining for GLUT1 was seen in the nerve fiber layer, the ganglion and photoreceptor cell bodies, the capillaries and the RPE of the retina, the basal infoldings of the pigmented and nonpigmented layers of the ciliary body, the capillary endothelium and posterior epithelium of the iris, the corneal epithelium and endothelium, and the endothelium lining of the canal of Schlemm. Müller cells, a type of retinal glial cell identified by morphology and by parallel staining for glial fibrillary acidic protein, also stained intensely positive for GLUT1. The pattern of GLUT1 immunoreactivity in the diabetic eyes was virtually identical to that in the nondiabetic specimens, with the notable exception that the neovascular endothelium of proliferative retinopathy did not stain for GLUT1.

CONCLUSIONS

These studies describe the heretofore unrecognized expression of immunoreactive GLUT1 in the ganglion cell layer of the retina, the endothelium lining the canal of Schlemm, the corneal endothelium, and the basal cells of the corneal epithelium of the human eye. The present study also provides evidence for immunoreactive GLUT1 in glial cells of the central nervous system. Because the expression of GLUT1 is characteristic of tissues that possess a barrier function, the absence of GLUT1 immunoreactivity in the neovascular tissue of proliferative diabetic retinopathy suggests that the loss of selective permeability is associated with an absence of facilitated glucose transport in this disorder.

Acanthamoeba sclerokeratitis

We treated a healthy soft contact lens wearer who developed Acanthamoeba sclerokeratitis in the left eye. The patient had severe pain and ring-shaped subepithelial infiltrates. The keratitis progressed and scleral nodules developed despite aggressive treatment with topical clotrimazole, dibromopropamidine isethionate, and corticosteroids. Corneal transplantation and cryotherapy were performed. The corneal button demonstrated Acanthamoeba cysts. Cultures of biopsy specimens taken from two different scleral nodules at two separate times were positive for Acanthamoeba. The disease progressed despite a second corneal graft and the addition of polyhexamethylene biguanide eyedrops. Enucleation of the left eye was required. Histopathologic examination of the specimen documented an Acanthamoeba cyst associated with a granulomatous inflammatory response deep in the sclera. Acanthamoeba scleritis may be associated with a poor prognosis, even with intensive medical and surgical treatment.

Complement system and host defense against staphylococcal endophthalmitis

PURPOSE

The authors studied the role of the complement system in host defense against Staphylococcus epidermidis and S. aureus endophthalmitis.

METHODS

Guinea pigs in the S. epidermidis model received an intravitreal injection of 7000 viable organisms, and guinea pigs in the S. aureus model received 50 viable organisms. The experimental animals in each model were decomplemented with intraperitoneal (IP) injections of cobra venom factor, whereas the control animals received IP injections of normal saline. Mean log bacterial counts in the vitreous and mean serum complement titers were compared in the experimental and control animals in each model on days 1, 2, 3, and 7.

RESULTS

In the S. epidermidis model, mean log bacterial counts in the vitreous were significantly higher in the experimental group than the control group on days 1 and 2 (P < 0.01) and on day 3 (P < 0.05). Mean serum complement titers were significantly lower in the experimental group at all days (P < 0.01). In the S. aureus model, mean log bacterial counts in the vitreous were significantly higher in the experimental group than the control group on day 2 (P < 0.05) and day 3 (P < 0.01). Mean serum complement titers were significantly lower in the experimental group on days 1, 2, and 3 (P < 0.01), but not on day 7.

CONCLUSION

These results suggest that decomplemented guinea pigs show impaired host defense to S. epidermidis and S. aureus endophthalmitis and that this defense is restored as complement levels approach normal.

Aspiration cytology of clear-cell lesions of the parotid gland: morphologic features and differential diagnosis

Clear-cell lesions of the parotid gland are uncommon but when studied by fine-needle aspiration may result in a clinically important but cytologically difficult differential diagnosis. Clear-cell lesions involving the parotid include acinic cell neoplasm, clear cell oncocytoma, mucoepidermoid carcinoma, primary clear-cell carcinoma, epithelial-myoepithelial carcinoma, and metastatic renal cell carcinoma. Accurate diagnosis is achieved by assessment of nuclear features, other cell populations present, and clinical data including radiographic studies.

Assignment of tear lipocalin gene to human chromosome 9q34-9qter

We assigned the gene for tear lipocalin to the long arm of human chromosome 9. Polyadenylated RNA was extracted from lacrimal gland. The coding region for tear lipocalin was amplified, sequenced and used to probe a panel of somatic cell hybrid DNA by Southern blot analysis. Regional mapping was accomplished by probing a panel of subfragments of the indicated chromosome. Restriction of genomic DNA with EcoRI failed to reveal any bands corresponding to the human tear lipocalin gene in mouse-human hybrids all of which lack chromosome 9. Southern blot analysis of human-hamster hybrids demonstrated a human 5.6 kb TaqI restriction fragment that segregated to the q34-qter region of chromosome 9 and assigned the gene for tear lipocalin to this region. Structurally homologous proteins of the lipocalin family, human placental protein 14, human alpha 1 microglobulin, and human brain prostaglandin synthase, have been mapped to this region. We suggest that the gene for tear lipocalin is part of an important lipocalin superfamily gene cluster on chromosome 9 within band q34.

Bilateral optic nerve cryptococcosis in sudden blindness in patients with acquired immune deficiency syndrome

PURPOSE

A neuroanatomic study was undertaken to search for the cause of sudden, simultaneously bilateral blindness in a patient with acquired immune deficiency syndrome who had cryptococcal meningitis.

METHODS

Careful gross examination was performed, and microscopic sections were cut at 50- to 100-microns intervals of the entire visual pathway.

RESULTS

Focal cryptococcosis destroyed segments of the right intracanalicular optic nerve and the left intraorbital optic nerve adjacent to the optic canal. The meninges were heavily infiltrated by Cryptococcus organisms around the optic tracts, optic nerves, and optic chiasm; however, only a few scattered cryptococcal organisms were found in the periphery of the chiasm contiguous with heavy meningeal infection. Blood vessels supplying the chiasm appeared normal. Generalized cerebral edema and focal vacuolization of periventricular white matter were evident.

CONCLUSION

The authors believe that sudden, simultaneously bilateral visual loss in this patient was caused by focal but fulminant necrosis of both optic nerves. However, the presence of cryptococcal organisms throughout the basal meninges and in the sheaths of both optic nerves suggests that cryptococcosis may produce visual loss by damaging multiple areas of the anterior visual pathway.

Aspiration biopsy cytology of primary cutaneous tumors

Primary cutaneous neoplasms may undergo fine needle aspiration during the workup of patients with suspected metastatic disease. Such aspirates present a wide range of epithelial and nonepithelial proliferations that must be separated from more common metastatic deposits. The majority of primary cutaneous tumors are composed of squamous or basaloid cells that can be confused with metastatic squamous cell carcinoma. In addition, primary cutaneous lymphomas and mesenchymal tumors morphologically overlap their more common systemic or metastatic counterparts in appearance. Both clinical and cytologic features aid in the differentiation of pilomatrixomas, basal cell carcinomas, sebaceous carcinomas, primary squamous cell carcinomas, Merkel cell tumors and epidermal inclusion cysts from metastatic squamous cell carcinomas. The presence of small basaloid cells in an aspiration smear favors the diagnosis of a primary neoplasm, such as pilomatrixoma or basal cell carcinoma. Clinical findings and cell marker studies are important in the cytologic diagnosis of primary cutaneous lymphomas. Complex convolutions in the nuclei of neoplastic lymphoid cells favor a primary cutaneous origin. We report the cytologic features of 94 primary cutaneous tumors seen in a series of 558 aspirates of subcutaneous and cutaneous nodules.

Bacterial endophthalmitis following sutureless cataract surgery

We examined a patient who developed group G streptococcal endophthalmitis following phacoemulsification with intraocular lens implantation and sutureless wound closure. Pathologic examination of the enucleated globe 1 month after surgery revealed an intense suppurative reaction centered in the anterior chamber and an open surgical wound filled with fibrinopurulent granulation tissue. Inadequate draping, a high number of instruments passing into and out of the eye during surgery, and wound testing for water tightness with viscoelastic substance in the eye were observed on a videotape of the surgery.

Effects of Cy to sine Arabino side-Impregnated Bioerodible Polymers on Glaucoma Filtration Surgery in Rabbits

A prospective, randomized double-masked placebo-controlled study was performed to determine the effects of a bioerodible polymer containing cytosine arabinoside (Ara-C) on the success of full thickness filtration surgery in 21 rabbits. The polymer was a polyanhydride composed of bis(pcarboxyphenoxy) propane and sebacic acid. The polymer and Ara-C (1 mg by weight) were combined and compressed into discs 3-mm and 1-mm thick. Control polymers contained no Ara-C. Posterior lip sclerectomy surgery was performed bilaterally, with one eye randomly receiving the polymer with the Ara-C and the fellow eye receiving the control polymer. All eyes were examined on the first postoperative day and every other day thereafter. Intraocular pressures (IOPs) were found to be significantly lower (p < 0.04) in the experimental eyes during the 5th through the 15th postoperative day, with the mean difference ranging from 3.5 to 6.0 mm Hg. The median number (+/-SE) of days until failure of the filters was 10.5 (+/-0.66) days in the control group and 15.2 (+/-1.94) days in the experimental group, the difference being statistically significant. There were no significant differences between the groups with regard to conjunctival injection, corneal epithelial defects, anterior chamber inflammation, lens changes, or intraoperative or postoperative complications. This study suggests that polymer drug delivery of Ara-C may be a safe and efficacious adjunct in temporarily increasing the success rate of glaucoma filtering surgery in a rabbit model.

Immune response to Staphylococcus epidermidis-induced endophthalmitis in a rabbit model

Although Staphylococcus epidermidis is the most common cause of postoperative pseudophakic endophthalmitis, little is known about the immune response to S. epidermidis-induced endophthalmitis. Using a rabbit model, the immune response to an intravitreal injection of 7000 S. epidermidis (group 1) or 30,000 S. epidermidis (group 2) organisms was investigated. Clinical evaluations showed that rabbits in group 2 had a more severe inflammatory reaction in the conjunctiva, cornea, iris, and vitreous than those in group 1. The inflammatory reaction in group 1 largely resolved by day 30; group 2 continued to show a severe inflammatory response. Histopathologic findings correlated with clinical findings, with rabbits in group 2 showing a more severe inflammatory reaction in both the anterior and posterior segments of the globe. Positive vitreous cultures for S. epidermidis were present in rabbits in group 1 on days 3, 7, 10, 14, and 21 but not thereafter. However, group 2 had higher vitreous colony counts at days 3, 7, and 14 and negative vitreous cultures thereafter. Neither group showed delayed hypersensitivity to S. epidermidis antigens (evaluated by skin tests). Serum immunoglobulin (Ig) G antibody levels to phenol-inactivated S. epidermidis and glycerol teichoic acid (GTA) increased progressively, reached a peak at days 10-14, and then declined in both groups. Serum IgA antibody levels to these antigens were not detected. Group 2 had a more prolonged IgG antibody response in vitreous and aqueous than group 1. Tear fluid showed the weakest IgG and IgA antibody response to S. epidermidis and GTA. S. epidermidis-induced endophthalmitis was associated with a humoral but not a delayed hypersensitivity response to this organism.

Lipomatous lesions of the parotid gland. Potential pitfalls in fine needle aspiration biopsy diagnosis

Nine cases of benign fatty tumors of the parotid studied initially by fine needle aspiration (FNA) biopsy and subsequently diagnosed by open biopsy were reviewed. All lesions presented as enlargements of the parotid gland. The cytologic diagnoses were correct in only five of the nine cases. While four of six FNA samples from lipomas were correctly diagnosed by cytology, the other two samples were classified as inadequate. Three cases of diffuse infiltration of the parotid by mature-appearing adipose tissue were cytologically characterized as "no diagnostic change" in two cases and sialosis in one case. The clinical, radiologic, cytologic and histologic features of these tumors are described to increase the familiarity of cytologists with these lesions, which may prevent unnecessary surgical intervention in some patients.

Ultrastructural and immunohistochemical features of coronal adenomas

We studied by electron microscopy three coronal adenomas discovered incidentally in eyes removed surgically. Tumor cells displayed prominent intercellular interdigitations with numerous desmosomes, mitochondria, abundant rough endoplasmic reticulum, and nuclei with membrane infoldings and a granular chromatin pattern. In these characteristics, the tumor cells were identical to nonpigmented ciliary epithelium of the ciliary processes. These growths contained abundant extracellular material, which showed a dimorphic pattern of complex reduplicated basal lamina and granular areas without structure. Immunohistochemical studies on formalin-fixed, paraffin-embedded coronal adenomas demonstrated type IV collagen and laminin in the extracellular material. These findings confirm that coronal adenomas develop from nonpigmented ciliary epithelium and that the extracellular material of these tumors contains components normally present in basement membranes.

Intraocular fine-needle aspiration biopsy of coronal adenomas

The cytologic findings from intraocular biopsy of coronal adenomas of three previously surgically enucleated eyes were studied. Cohesive clusters of nonpigmented epithelial cells were observed. Clusters of epithelial cells were surrounded by characteristic intercellular matrix material. Coronal adenomas have been clinically mistaken for intraocular melanomas. It is important for pathologists to be familiar with the aspiration cytology of the coronal adenoma to avoid unnecessary enucleation or iridocyclectomy.

Diagnosis of salivary gland tumors by fine-needle aspiration cytology: a review of clinical utility and pitfalls

Fine-needle aspiration cytology has become a frequently used technique for the diagnosis of neoplasms of the head and neck. While the method has a high sensitivity and specificity for the diagnosis of salivary gland lesions, important pitfalls for the cytologic diagnosis of these lesions exist. This paper discusses the diagnostic pitfalls and investigates strategies for the evaluation of salivary gland masses.

Use of bioerodible polymers impregnated with mitomycin in glaucoma filtration surgery in rabbits

A prospective, randomized, double-masked, and placebo-controlled study was performed to evaluate the effects of a localized and sustained release of mitomycin on the success of glaucoma filtration surgery in rabbits. A bioerodible polymer was used as the drug carrier. Full-thickness filtration surgeries were performed and data from 22 rabbits were collected. One eye received a polymer impregnated with mitomycin (0.02 mg or 0.06 mg), while the fellow eye received a drug-free polymer. Intraocular pressure, bleb survival, and postoperative complications were investigated. Intraocular pressures remained lower for a longer period of time (P less than 0.004) and filtration blebs lasted longer (P less than 0.05) in experimental eyes than in control eyes. Conjunctivitis and sectorial corneal haze occurred more frequently in eyes treated with the higher dosage mitomycin compared with control eyes. The use of mitomycin-C in a polymer delivery system appeared to promote the success of glaucoma filtration surgery in rabbits. With the lower dosage of mitomycin, clinically significant ocular toxicity was not noted.