Ultrastructural analysis of the lamina cribrosa after radial optic neurotomy.

Radial optic neurotomy (RON) has been proposed for alleviation of the "scleral outlet compartment syndrome" at the level of the lamina cribrosa, which is thought to play a pathoetiologic role in central retinal vein occlusion (CRVO). The aim of this study has been to analyze the ultrastructural alterations of the lamina cribrosa after RON to gain new insights in the underlying pathomechanical factors. Fifteen donor eyes underwent a standardized open-sky-vitrectomy and RON after removal of the anterior eye segment for keratoplasty.

Drainage of tears: impact on the ocular surface and lacrimal system.

The human efferent tear ducts are part of the lacrimal system. Because little knowledge exists concerning the physiology of the nasolacrimal system, and hence its patho- physiology, the nasolacrimal system has received almost no consideration as a possible factor in dry eye. The human nasolacrimal ducts consist of the upper and the lower lacrimal canaliculus, the lacrimal sac, and the nasolacrimal duct.

[Tear outflow. Impact of mucins and TFF-peptides].

The epithelial lining of the lacrimal sac and the nasolacrimal duct consists of pseudo-stratified, columnar epithelia rich in goblet cells. Major secretory products of the epithelial cells are mucins together with TFF peptides. Expression and distribution of several mucins and TFF peptides in the human efferent tear ducts was investigated by means of reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry.

The cavernous body of the human efferent tear ducts contributes to regulation of tear outflow.

Purpose: To test the hypothesis that the surrounding vascular plexus of the lacrimal sac and the nasolacrimal duct contributes to the regulation of tear outflow.

Methods: Experiments in 30 probands aged between 15 and 37 years were performed in both nasolacrimal systems of each subject by observing with an endoscope the transit time of an applied tear drop containing fluorescein dye until its entry into the inferior meatus of the nose. Four different experiments were performed to determine the median transit time under normal conditions and the influence on transit time of a decongestant drug, a foreign body on the ocular surface, and a decongestant drug applied together with a foreign body on the ocular surface.

Characterization of mucins in human lacrimal sac and nasolacrimal duct.

Purpose: Mucins are polymers that may reduce drag and enhance tear outflow. Mucin expression and distribution in human efferent tear ducts were tested in the physiological state, and potential differences in the expression pattern were investigated in the presence of primary acquired dacryostenosis (PANDO).

Methods: Expression of mucins in human lacrimal sac and nasolacrimal ducts was monitored by reverse transcription-polymerase chain reaction analysis.

Loss of tear duct-associated lymphoid tissue in association with the scarring of symptomatic dacryostenosis.

Objective: To determine whether organized mucosa-associated lymphoid tissue (MALT) is a normal component of the human efferent tear ducts or is acquired in reaction to chronic inflammation.

Design: Nonrandomized comparative (cadaver controlled) study with histopathologic correlations.

Materials: Tissue specimens from nasolacrimal ducts of 38 patients undergoing endonasal dacryocystorhinostomy in postinflammatory dacryostenosis with signs of chronic inflammation were analyzed using histologic examination and immunohistochemical studies.

TFF peptides in the human efferent tear ducts.

Purpose: To determine whether the lining epithelium of the human lacrimal sac and nasolacrimal duct synthesizes TFF peptides (formerly P-domain peptides, trefoil factors), a family of mucin-associated secretory peptides.

Methods: Expression of TFF peptides in human lacrimal sac and nasolacrimal ducts was monitored by reverse transcription-polymerase chain reaction and Western blot analysis. Antisera specific for TFF peptides were used in immunohistochemical analysis to determine the presence and distribution of all three TFF peptides in epithelia of the lacrimal passage.

Animal model for the absorption of lipophilic substances from tear fluid by the epithelium of the nasolacrimal ducts.

Purpose: To compare the nasolacrimal tissues of several species to see how closely they resemble the human and to measure nasolacrimal absorption of a substance, to show that an absorption pathway exists for substances placed in the external eye, other than directly through the cornea or conjunctiva.

Methods: The nasolacrimal systems of six different vertebrates were investigated by light microscopy to find a species with a nasolacrimal system comparable to that of humans, for use in absorption experiments. In addition to primates, rabbits were revealed by histology to have a lacrimal system closely comparable to that of humans.

[Nasolacrimal ducts and the dry eye].

Background: The knowledge regarding the pathogenesis, diagnosis, and treatment of dry eye has made large advances in recent years. However, many questions are still unanswered. Although the nasolacrimal ducts are part of the tear system they have been paid nearly no attention regarding dry eye.

Morphological studies of the optic canal.

Background: In some cases of closed head injuries after minor blunt trauma, an amaurosis can occur. Our knowledge concerning the pathophysiological mechanisms of traumatic optic neuropathy is limited. The aim of this study is to analyze the morphology of the optic canal in order to understand the effect of mechanical forces in the optic canal and the consecutive injuries.

New insights into the pathophysiology of primary acquired dacryostenosis.

Objective: To obtain new insights into the pathophysiology of primary acquired dacryostenosis.

Design: Comparative autopsy tissue study with histopathologic correlations.

Materials: Tissue specimens from the human nasolacrimal ducts of 36 patients undergoing endonasal dacryocystorhinostomy within a framework of primary acquired dacryostenosis were analyzed by histologic studies and electron microscopic examination.

[The efferent lacrimal ducts of the human. Morphological and biochemical studies].

Purpose: Infections occur frequently in the region of the efferent tear ducts. Exact knowledge of the anatomical structure and of cellular defense mechanisms is necessary to understand the pathological processes. This study analyzed the efferent tear ducts with regard to physiological function and possible defense mechanism against infections.

The cavernous body of the human efferent tear ducts: function in tear outflow mechanism.

Purpose: To determine the structure and function of a system of large blood vessels integrated in the bony canal between the orbit and the inferior nasal duct.

Methods: Thirty-one dissected lacrimal systems of adults were analyzed by using gross anatomy, histology, and electron microscopy as well as corrosion vascular casts.

Results: More than two thirds of the bony canal between orbit and inferior nasal duct is filled by a plexus of wide-lumened veins and arteries.

Innervation of the cavernous body of the human efferent tear ducts and function in tear outflow mechanism.

The lacrimal sac and nasolacrimal duct are surrounded by a wide cavernous system of veins and arteries comparable to a cavernous body. The present study aimed to demonstrate the ultrastructure of the nervous tissue and the localisation of neuropeptides involved in the innervation of the cavernous body, a topic not previously investigated. Different S-100 protein antisera, neuronal markers (neuron-specific enolase, anti-200 kDa neurofilament), neuropeptides (substance P, neuropeptide Y, calcitonin gene-related peptide, vasoactive intestinal polypeptide) and the neuronal enzyme tyrosine hydroxylase were used to demonstrate the distribution pattern of the nervous tissue.

[The joint capsule of the cricoarytenoid joint: biomechanical and clinical aspects].

Background: Impaired movement of the cricoarytenoid joint with hoarseness and immobility of the vocal ligament may occur as a consequence of laryngeal trauma and joint disease. Little is known to date about the cricoarytenoid joint capsule and its role in joint pathology.

Methods: The present study analyses the structure of the cricoarytenoid joint capsule by means of histological, immunohistochemical, and scanning electron microscopical methods.

Mucosa-associated lymphoid tissue in human efferent tear ducts.

The recent description of primary marginal zone lymphomas in human efferent tear ducts with typical features of lymphomas arising in mucosa-associated lymphoid tissue (MALT) infers the presence of MALT in the human efferent tear ducts. To date, studies have not established clearly whether organised MALT occurs in normal human efferent tear ducts. To elucidate this problem, efferent lacrimal pathways from unselected body donors with unknown prior history of efferent tear duct, ocular, or nasal disease were examined for the presence of organised MALT.

What happens to tears inside the efferent lacrimal passage? An animal experimental study.

Background: To determine whether absorption of protein components of the tear fluid occurs in normal efferent tear ducts, an animal experiment was carried out.

Methods: Iodinated albumin was dropped into eyes of female rats. After 10, 20 or 60 min the rats were killed, blood collected and the heads embedded for histological examination.

Epithelial-connective tissue boundary in the oral part of the human soft palate.

The papillary layer of the oral part of the human soft palate was studied in 31 subjects of different age by means of histological, immunohistochemical and scanning electron microscopical methods. For scanning electron microscopy a new maceration method was introduced. Results determine epithelial thickness, height and density of connective tissue papillae and their 3-dimensional architecture inside the lining epithelium as well as the collagenous arrangement of the openings of the glandular ducts.

Functional anatomy of the human efferent tear ducts: a new theory of tear outflow mechanism.

Background: The mechanism of lacrimal drainage under physiological conditions is controversial. The aim of this study was to analyze the three-dimensional architecture of human efferent tear ducts from functional and clinical points of view. A new theory of tear outflow is discussed.

Functional anatomy of human lacrimal duct epithelium.

Resorption of tear fluid in the lacrimal ducts has hitherto been controversial; one reason for this has been insufficient knowledge of the anatomical structure and function of the lacrimal duct epithelium. The present study analyzes the structure of lacrimal duct epithelium by means of histological, histochemical, immunohistochemical and electronmicroscopical methods and draws a conclusion about its physiological function regarding its role in immunodeficiency. Investigations were performed on 31 lacrimal systems of 17 male and 14 female individuals (aged 54-88 years).

Radiologic and histopathologic findings in a rare case of complex occult spinal dysraphism with association of a lumbar fibrolipoma, neurenteric cyst and tethered cord syndrome.

We present the case of a 60-year-old farmer who reported non-specific back pains for the past 30 years. Increasing paralysis of the left leg led to hospitalization. A complex occult spinal dysraphism comprising a fibrolipoma of the conus medullaris, an neurenteric cyst, and a tethered cord syndrome was diagnosed and operated on.

[Changes in extracellular matrix in the lamina cribosa of patients with secondary glaucoma].

The aim of this study was to analyze the localization and distribution of extracellular matrix in normal and glaucomatous damaged optic discs using immunohistochemical methods. Five eyes donated for corneal allografting without any history of glaucoma and three other eyes with secondary glaucoma were studied. Immunohistochemical reactions were performed with antibodies against collagen types I, III, IV and VI and against laminin, proliferating antigen KI67 and GFAP.

SEM studies of the collagen architecture of the human lamina cribrosa: normal and pathological findings.

The arrangement of the collagen fibrils of the lamina cribrosa was analyzed by using scanning electron microscopy with clinical regard to morphological alterations in cases of glaucoma at different stages. Adult eyes with no apparent pathological changes and specimens from patients with absolute glaucoma were studied. In the lamina cribrosa of nonpathological eyes the collagen fibrils are arranged circularly around the points of passage of axons and vessels.