bluuebunny/crossref_metadata_2025 huggingface dataset:
Bacterial growth in the conjunctival sac and the local defense of the outer eye
Authors: Jensen O. L. , Gluud B. S.
Published: May 2009

Abstract25 patients admitted for cataract surgery were subjected to conjunctival bacterial culturings preoperatively and during the postoperative observation period. Simultanously lactoferrin (LF), lysozyme (LY) and secretory immunoglobulin A (s‐IgA) were measured in tears. The preoperative flora disclosed the growth of Staphylococcus albus (SA) and diphtheroids. Other species were only sporadically present. There was a significant rise in number of patients affected by SA and diphtheroids postoperatively (from 60 to 80%), wheras other bacteria were not present to any significant extent. LF, LY and s‐IgA concentration decreased to about 50% of the preoperative level in the early postoperative period gradually returning towards their initial concentration. Correlating an antibacterial score with bacterial score we found a significant inverse relationship between the two (P<0.05).
A comparative analysis of the collagen type and distribution in the trabecular meshwork, sclera, lamina cribrosa and the optic nerve in the human eye
Authors: Tengroth B. , Rehnberg M. , Amitzboll T
Published: May 2009

Abstract A theory has been advanced (Tengroth et al 1984) that one common factor might be involved in the pathogenesis of chronic open angle glaucoma. The mechanical properties of the collagen could be one such factor. To characterize the collagen composition of the critical structures in cases with chronic open angle glaucoma i.e. the trabecular meshwork and the lamina cribrosa in the human eye, the following investigations were performed. Using immunperoxidase technique and type specific antibodies to the genetically distinct collagen types I, III, IV and procollagen I along with the major non collagen proteins in the extracellular matrix laminin and fibronectin a light microscopic study was undertaken on the trabecular meshwork, cornea, sclera, lamina cribrosa and the optic nerve of the human eye. Furthermore biochemical analysis was performed on the collagen associated aminoacids hydroxyproline (Hyp), hydroxylysine (Hyl) and prolin (Pro) from microdissected samples of trabecular meshwork, sclera, lamina cribrosa and optic nerve. Both the immunohistological and the biochemical findings suggested similarities in the collagen composition between the trabecular meshwork and the lamina cribrosa. The immunohistochemical findings showed stronger staining of type III and IV in the trabecular meshwork and lamina cribrosa as compared to sclera or cornea while the opposite was true for type I and procollagen I. Fibronectin and laminin were present in both the trabecular meshwork and lamina cribrosa. These findings were in agreement with the amino acid analysis when the Hyp/Hyl ratio was calculated for each sample. The trabecular meshwork and lamina cribrosa had almost identical ratios which were lower than in the sclera and the optic nerve retrolaminary, indicating a higher proportion of type IV in the former structures. The biochemical and immunohistochemical findings suggest a similar collagen composition in the trabecular meshwork and lamina cribrosa as opposed to the cornea, sclera and optic nerve proper. A common embryological background of the critical tissues is discussed.
Theoretical relations between light streak characteristics and optical properties of retinal vessels
Authors: Brinchmann‐Hansen Olaf , Heier Halvor
Published: May 2009

Abstract Due to the various surfaces of overlying structures, direct high magnification studies of retinal vessels in the living human eye is not yet possible. Our knowledge of microcirculatory mechanics of flow and morphological changes in vessel walls, is obtained by analysing information contained in reflected light from the retina. Different characteristics of the central light reflex seen on retinal vessels have, in both clinical and theoretical studies, been sought correlated to morphological wall changes in various systemic vascular diseases. In this paper we perform a theoretical study on effects of density changes and increased thickness of a vessel wall on the width and the intensity of the light streak. Assuming that the reflex originates from the intravascular column of streaming erythrocytes, we show that variations in thickness of the wall or changes in its refractive index do not influence the final image of the width of the reflex. The intensity, however, is affected by density changes in overlying structures.
Prevalence of pseudoexfoliations in a population 65–74 years of age
Authors: Ekström Curt
Published: May 2009

Abstract. In a population study from a rural district in the middle part of Sweden pseudoexfoliations were found in 18% of subjects 65–74 years of age and were more common in females than in males.
Prevalence of Ocular Disease and Blindness in a Rural Area in the Eastern Region of Iceland during 1980 through 1984
Authors: Jonasson F. , Thordarson K.
Published: May 2009

Abstract.The main emphasis in this study is on the three most common potentially blinding diseases in the age group 43 years and older, i.e. cataract, age related macular degeneration and open angle glaucoma. The prevalence of all three diseases increases with advancing age (P<0.001, corr.>0.8).

In the age group 63 years and older there is a statistically significant difference in the occurrance of cataracts between females and males (P<0.02). Females outnumber males and the former appear to develop cataract at an earlier age than men.

Among persons 73 years of age and older there is a statistically significant difference in the occurrance of open angle glaucoma between males and females (P<0.05), whereby males outnumbered females.

Persons with age related macular degeneration were divided into an exudative group and an atrophic group. There was no sex difference in the atrophic group, whereas females outnumber males by 2:1 in the exudative group, which is mainly accounted for by overrepresentation of females 83 years and older. Persons 83 years and older who had age related macular degeneration also had cataracts in all instances and open angle glaucoma in 23.8% of cases.

Sixteen persons were legally blind i.e. had visual acuity ≤6/60 in the better eye or visual field <10° in the better eye. Eight persons thereof, were ≥ 83 years of age.
Refraction and Interpupillary Distance Measurements of Adult Icelanders with special reference to presbyopes possible use of supermarket standard spectacles
Authors: Jonasson F. , Thordarson K.
Published: May 2009

Abstract. In Iceland refraction is exclusively performed by ophthalmologists who at the same time provide a comprehensive screening for ocular disease. One of the authors travelled three times a year during 1980 through 1984 providing ophthalmic services for rural area in the Eastern Region of Iceland. By the 1st of December 1982 the population 43 years of age and older was 925 persons. This age group is likely to require reading glasses. 751 persons, i.e. 81.2%, had eye examination including visual acuity tests. 730 persons were refracted i.e. 71.9%, and interpupillary distance for near was mesured for 555 persons, i.e. 60% of the population. The results were used to estimate the suitability and usefulness of standard supermarket glasses. In 32.1% of the cases, standard reading glasses were found to be unsuitable because of refraction and in 14.2% of the cases, glasses with appropriate interpupillary distance were unavailable in the store. Thus almost half of the examined persons would not have found suitable glasses even if they had been correct in their selection in all instances, which is impossible.
Tarsorraphy in the treatment of persistent corneal lesions
Authors: Pakarinen Mirja , Tervo Timo , Tarkkanen Ahti
Published: May 2009

Abstract. Altogether 38 tarsorraphies were carried out to 19 patients with corneal epithelial defects resistant to conventional therapy. The main operaive indications were lagothalmos (9), dry eyes (12) and inadequate blinking (6 patients). Corneal ulcer was detected in 17 eyes, six of which perforated. All patients had been treated from one week to 16 months (mean 3.5 months) without healing. Retarsorraphy was needed in 6 eyes. In perforations tarsorraphy was combined to tissue adhesive (3 eyes) or to therapeutic contact lens (4 eyes) or to conjunctival flap (2 eyes). The corneal epithelium healed in all except 2 cases (one perforation, one ulcer that is slowly improving). Five of the 6 perforations could also be cured without grafting. One eye of a severely debilitated patient was treated with a Gundersen's conjunctival flap and total tarsorraphy, but remained hazy.

We consider, that tarsorraphy is valuable in treating corneal lesions due to lagophthalmos, dry eyes or disturbed lid function. It can also be used in threatening of manifest corneal perforation, if combined with the use of tissue adhesive or therapeutic contact lens.
Keratoplasties performed at Rikshospitalet, Oslo, Norway A retrospective study
Authors: Anseth Erik , Medin Walther , Anseth Arvid
Published: May 2009

Abstract. Retrospective study was performed of 183 keratoplasties on human patients at Rikshospitalet, Oslo between November 80 and December 86. Penetrating technique others 5. There were 19 reoperations and 9 of these were keratocous 41, bullous keratopathy 35, keratitis herpetica 35, keratitis of unknown origin 23, interstitial/phlyctenular keratitis 20, corneal trauma 13, dystrophia/Fuch's dystrophia 11, others 5. There were 19 reoperations and 9 of these were keratitis herpetica. The patients with keratoconus had the best visual result and keratitis herpetica the poorest.
Visual Function in Laurence‐Moon‐Bardet‐Biedl Syndrome A Survey of 26 Cases
Authors: Riise Ruth
Published: May 2009

Abstract  In 1984, 32 persons with Laurence‐Moon‐Bardet‐Biedl syndrome (LMBB syndrome) were registered in Norway. Of these, 26 stayed for 10 days at the Frambu Health Centre, where they consulted a pediatrician, a psychologist, a dentist, a social worker, a geneticist, a teacher for the blind and an ophthalmologist.

The ocular examination showed the eye disease in cases of LMBB syndrome to be homogeneous and fulminant tapetoretinal degeneration of the retinitis pigmentosa type.
Experience with Ruthenium106‐treatment of uveal malignant melanoma
Authors: Laatikainen Leila , Tarkkanen Ahti
Published: May 2009

Abstract. In 1981–1986, 25 eyes with malignant melanoma of the uvea were treated with beta irradiation using ruthenium106 plaques. In 21 cases the tumour originated in the choroid, in 4 cases in the ciliary body. In 12 eyes it was within 3 mm from the optic disc or the fovea, and the mean height (± SEM) was 5.2 ± 0.4 mm. Three eyes received two sets of irradiation with 1.1‐1.7 years' interval. After a mean followup of 1.6 years (range 0.5‐5.6) the tumour had decreased in size in 12, was unchanged in 6, and had progressed in 7 eyes, 4 of the latter were enucleated. In 3 patients metastases were diagnosed (2.0–2.9 years after irradiation), and 1 patient has died (3.3 years after the first irradiation). Twelve eyes have retained useful vision (0.05 or better), but in some of them a tendency to deterioration was observed 3–5 years after treatment due to radiation maculopathy. Other causes of visual loss were the centrally located tumour itself, exudative detachment of the retina, and persistent vitreous haemorrhage.
Contusion Rupture of The Globe
Authors: Eide Nils , Syrdalen Per
Published: May 2009

Abstract. Severe contusion‐injuries caused rupture of the globe in 20 eyes in 18 patients. 14 eyes had an open rupture (OR) and primary closure was performed in 13 eyes and one eye was enucleated. Six eyes with closed rupture (CR) had no emergency exploration. In both types of rupture, we intended to do vitrectomy within 14 days. In 12 cases vitrectomy was combined with retinal detachment surgery, lens extraction and gas injection. The upper‐lateral quadrant close to the limbus was the most common site of rupture (12 eyes). In 8 eyes the length of the rupture exceeded one quadrant. The lens was extruded in 9 of 14 eyes with OR. Vision preoperatively was in all eyes only light perception. Useful vision (counting fingers or better) was obtained in 7 of 13 eyes with OR and 2 of 5 eyes with CR, excluding 2 totally blind eyes upon admission, one eye in each group. Three patients became totally blind, one patient was hit in her last eye and two patients had bilateral ruptures and these eyes could not be saved.
A subhyaloid haemorrhage as the presenting symptom of bilateral optic neuropathy
Authors: Kerty Emilia , Eide Nils , Hapnes Rune
Published: May 2009

Abstract. A 28 year‐old man with a spontaneous vitreous haemorrhage as the first sign of Leber's optic atrophy is presented. The blood collected in a central retrohyaloid area covering the left macula. The exact starting point of the haemorrhage was never positively identified, but it seemed to originate from an area of microangiopathy adjacent to the optic disc. For 8–10 months the vision of the left eye gradually decreased to counting fingers.

A year later the visual acuity dropped to the same level on the right eye. The picture was compatible with Leber's optic atrophy. Other disorders causing bilateral optic neuropathy were excluded. A careful family history revealed several cases of visual problems for several generations. Vitreous haemorrhage as the first sign of Leber's optic atrophy has not previously been reported. Peripapillar microangiopathy, however, has been desribed in the asymptomatic stage of the disease.
THE CHAMBER ANGLE IN EXFOLIATION SYNDROME
Authors: Sampaolesi Roberto , Zarate Jorge , Croxato Oscar
Published: May 2009

Abstract. The clinical picture of the chamber angle in capsular glaucoma is described. One or more waves of pigment overpass Schwalbe's line and accumulate on the posterior face of the cornea. These waves are found in the chamber angle between 4 and 8 o'clock across 6 o'clock. The pathological anatomy of the chamber angle in the exfoliation is studied with light microscopy, scanning electronmicroscopy and transmission electronmicroscopy in relation with the material of pseudoexfoliation and pigment granules and the difference with the pigmentary glaucoma is shown.
EXFOLIATION SYNDROME IN VARIOUS ETHNIC POPULATIONS
Authors: Forsius Henrik
Published: May 2009

Abstract. This introductory lecture to the epidemiological session in the Workshop on the Exfoliation Syndrome (ES) gathers together figures for the prevalence of ES around the world. Prevalence figures from published reports are shown in the text separately for each country. Four ways of comparing the prevalences are used. 1) Prevalences in people over 60 years of age, 2) Percentages of glaucoma in persons with ES, 3) Percentages of ES in patients with glaucoma or ocular hypertension, with separate statistics for the proportion of capsular glaucoma in patients treated with laser trabeculoplasty (LTP), 4) Prevalence of ES in patients with cataract. The major differences in prevalence can partly be explained by the different techniques used in the investigations. Very few authors have studied people in different countries, which is the best way of obtaining comparable results. The author has personally studied Finns, Lapps, Eskimos in Greenland, Canada and Alaska, Icelanders, populations in Tunis, India and Peru and four populations in the USSR by the same technique. The prevalences vary from 0 % in Eskimos to 21 % in Finns over 60 years of age, and are at the same high level in Lapps, Finns, Russians in Novosibirsk and Icelanders, but significantly lower in all the others. The results support the opinion that ES is not uniformly distributed in all countries, and this is confirmed by many reports from different countries in this workshop.
EXFOLIATION SYNDROME IN THE SOUTHEASTERN UNITED STATES II. CHARACTERISTICS OF PATIENT POPULATION AND CLINICAL COURSE
Authors: Crittendon John J. , Shields M. Bruce
Published: May 2009

Abstract. Fifty‐three patients with the exfoliation syndrome, seen at the Duke University Eye Center, Durham, North Carolina, were characterized by a mean age of 71.3 years, a predilection toward women (38: 15), and a marked preponderance of whites to blacks (51: 2). There were 31 unilateral and 22 bilateral cases on the initial exam, with glaucoma in 62 of the 75 eyes with exfoliation, as well as 15 of the fellow, non‐exfoliation eyes. The incidence of glaucoma is undoubtedly skewed, since the patients were from a glaucoma referral practice. Twenty‐four patients were followed from six months to ten years, with a mean of three years, during which time four patients progressed from unilateral to bilateral exfoliation and five more patients acquired glaucoma in eyes with the exfoliation syndrome. The glaucoma associated with the exfoliation syndrome was typically difficult to treat with a high percentage of patients requiring multiple medications or surgical intervention.
EXFOLIATION SYNDROME AMONG SAUDIS
Authors: Summanen Paula , Tönjum Asbjörn M.
Published: May 2009

Abstract. The prevalence of exfoliation syndrome among Saudis was determined during the National Survey of Blindness and Eye Disease in 1984 in Kingdom of Saudi Arabia. The subsample of this study consists of 376 persons aged 40 years or more from 50 different locations examined under mydriasis by the authors using Kowa hand‐held microscope. There were 192 men and 184 women with the mean age of 56.0 ± 1.2 years (median 53.5 years, range 40–95 years).

The overall prevalence of exfoliation syndrome was 9.3%: in the age group 40 to 49 years 1.6%, 50 to 59 years 7.8%, 60 to 69 years 8.9%, and 26.5% in persons 70 years of age and over.

No significant association was found between exfoliation syndrome and sex or parental kinship.

In 16 persons the exfoliation syndrome was unilateral, and in 19 persons bilateral. In 24 eyes the phenomenon could not be evaluated due to the anterior segment pathology.

Exfoliation syndrome was associated with higher intraocular pressure (20 ± 3 mmHg (n = 49) vs. 17 ± 0.4 mmHg (n = 601), P < 0.05), and more cataract changes (P < 0.001) than eyes without. These eyes were also associated with poorer visual acuity than the eyes without exfoliation syndrome: in 26 of 35 persons with exfoliation syndrome, the affected eye was the better eye but in 35% the vision was <0.05 (< 3/60) i.e. the person was blind, compared to 6% of persons whose better eye did not have exfoliation syndrome (P < 0.001).
The role of environmental factors and hereditary predisposition in the causation of low myopia
Authors: Mohan Madan , Pakrasi Sudipto , Garg S. P.
Published: May 2009

Abstract. Various environmental factors have been implicated in the etiology of myopia. An attempt was made quantitatively to estimate some such environmental factors, as based on the presence or absence of a family history of myopia. Age range was 10–21 years. The 200 subjects included in the study were further divided according to emmetropia/myopia. The factors studied in the four subgroups were amount of near work done per day, head posture and illumination level while doing near work, acute fevers, chronic illness, acute or recurrent diarrhea, nutritional status, and income levels. A correlation was found between myopia and near work, head posture and income levels.
Ocular haemodynamics in cataractous eyes
Authors: Hopkins Sharon D.
Published: May 2009

Abstract Pulsatile ocular blood flow, systolic and diastolic intraocular pressures and ocular perfusion pressures were measured in a group of 10 patients (mean age 67 ± 3 years) with bilateral senile cataract. Each pair of eyes comprised one phakic and one pseudophakic eye. The results are compared to a group of 8 subjects (mean age 65 ± 4 years) with no apparent ocular pathology. The mean ocular pulsatile blood flow of 394 ± 52 μl min‐1 in the cataractous eyes was significantly reduced P < 0.001) compared to that of the control group (571 ± 40 μl min‐1). Results were similar for undisturbed cataractous eyes (mean pusatile blood flow = 400 ± 54 μl min‐1) and pseudophakic eyes (mean pulsatile blood flow = 388 ± 51 μl min‐1). The intraocular pressures were within normal limits (systolic intraocular pressure = 19.7 ± 0.7 mmHg, diastolic intraocular pressure = 17.5 ± 0.6 mmHg) as were the ocular perfusion pressures (73.7 ± 0.5 mmHg). The results provide evidence of decreased pulsatile ocular blood flow and associated ischaemia in cataractous eyes.
Surgical procedures in the treatment of most severe eye burns
Authors: Reim Martin , Teping C.
Published: May 2009

Abstract Report of some clinical observations in 16 patients with severe and most severe burns of 19 eyes. Major problems were delayed regeneration of the epithelium, extensive ulceration of the sclera near the limbus, and subsequent corneal ulceration. The therapy with anti‐inflammatory drugs, macromolecular hyaluronic acid, fi‐bronectin, epidermal growth factor, free transplants of oral mucosa and conjunctiva was sometimes helpful, but could not induce stable epithelial regeneration. The major problem remained the inability of the epithelium to regenerate on the cornea. Therefore, an artificial epithelium was applied in many cases. When healthy conjunctiva touched closely the artificial epithelium at the limbus, it remained tightly attached to the corneal stroma, preserved it's structure and even prevented corneal vascularisation for many months. However, when corneo‐scleral ulceration was present, the artificial epithelium failed to protect the corneal stroma from secondary ulceration and sloughed off. Therefore, new surgical procedures, a conjunctiva‐Tenon flap and a Tenon plasty were introduced to cover and to cure corneoscleral ulceration. These operations formed a new limbus, attached tightly to the rim of the artificial epithelium and prevented secondary ulceration underneath. Then under the protection of the artificial epithelium and the Tenon plasty the eye could be treated topically with corticosteroids for a long time. When the inflammatory response to the burn was healed, the natural epithelium recovered and the eye became ready for successful keratoplasty.
Peptidergic and catecholaminergic fibers in the human corneal epithelium
Authors: Ueda Shunsuke , del Cerro Manuel , LoCascio Joseph A. , Aquavella James V.
Published: May 2009

Abstract Innervation of the clinically normal human corneal epithelium was investigated utilizing immunohistochemical and electron microscopic techniques. All corneal epithelial sheets examined demonstrated neuron specific enolase (NSE: a non‐specific marker for neural elements), calcitonin gene‐related peptide (CGRP: a putative marker for sensory fibers), and tyrosine hydroxylase (TH: a marker for catecholaminergic nerves) immu‐noreactive fibers. NSE, CGRP, and TH fibers formed a dense basal epithelial plexus. The CGrp fibers tended to have beaded profiles, while TH fibers were smooth. Numerous free nerve endings originating from the basal epithelial plexus og NSE and CGRP fibers terminated throughout the thickness of epithelium. The densities of fibers in the basal epithelial nerve plexus were: NSE > CGRP > TH. Transmission electron microscopy demonstrated two types of epithelial nerve fibers, one containing large dense‐core vesicles and another small dense‐core visicles. Both types contained clear vesicles. These large and small dense‐core vesicle fibers appeared to correspond to the CGRP and TH immunoreactive fibers, respectively. These results provide morphological baseline data on the normal sensory and sympathetic corneal epithelial innervation.
The molecular basis of neurotrophic keratitis
Authors: Cavanagh H. Dwight , Colley Ann M.
Published: May 2009

Abstract Endogenous proliferation of corneal epithelial cells is regulated by a bidirectional control process characterized by an adrenergic, cAMP‐dependent ‘off’, and a cholinergic, muscarinic cGMP‐dependent ‘on’ response. The adrenergic receptor(s) are located in the plasma membrane (microsomal fraction), whereas the novel feature of the system is a cholinergic receptor specific for acetylcholine (ACH) located in the nuclear membrane. Exogenous substances which raise intracellular cAMP levels such as isoproterenol or PGE1, shut off epithelial mitosis; and, carbamylcholine or ACH raise intranuclear cGMP levels and increase mitosis by specific, regulatory stimulation of RNA‐polymerase II activity. We believe that this regulatory system explains the transitory mitotic suppression induced by superficial corneal wounding (interruption of adrenergic fibres, ‘chalone‐effect’); and the marked, permanent depression of epithelial mitosis associated with decreased intracellular ACH levels which are produced by total corneal denervation, and which results in neurotrophic keratitis.
Time course of human conjunctival mast cell degranulation in response to compound 48/80
Authors: Udell Ira J. , Kenyon Kenneth R. , Hanninen Laila A. , Abelson Mark B.
Published: May 2009

Abstract Compound 48/80, a non‐immunogenic mast cell degranulatory agent, is known to produce the signs and symptoms of ocular allergy. Maximal mast cell degranulation of human conjunctiva occurred within the first hour after stimulation by a single topical dose of compound 48/80 (20 μl, 7.5 mg/ml). The average percentage of fully degranulated mast cells in treated specimens (n=9) was 31% (range 5–60%) versus 6% (range 0–20%) in control specimens (n=5). Exact correlates of representative granulated, partially degranulated, and fully degranulated mast cells were determined by light and transmission electron microscopy.
REACTIVE FORMATION OF HYALURONIC ACID IN THE RABBIT CORNEAL ALKALI BURN
Authors: Fagerholm Per , Fitzsimmons Thomas , Härfstrand Anders , Schenholm Mona
Published: May 2009

Abstract The presence and distribution of reactively formed hyaluronic acid (HA) was assessed in the rabbit cornea following a penetrating alkali burn. The injury was inflicted by applying a round, 5.5 mm, filter paper soaked in 1 N NaOH centrally on the cornea for 60 seconds.

Biochemical analysis revealed a significant increase of HA two weeks after injury, a peak concentration after 1 month, and a decrease again at three months.

Histochemical analysis revealed the presence of hyaluronic acid in the healing epithelium, in the repopulating keratocytes/fibroblasts, and in the cells forming the retrocorneal membrane. Extensive amounts filled lacunae in the stroma as well as the spaces between collagen lamellae. A slow restoration of normal appearing corneal stroma took place at the periphery. Significant staining for HA in lacunae was present centrally in the wound after three months.
Ultrasound biomicroscopy in glaucoma
Authors: Pavlin Charles J. , Foster F. Stuart
Published: May 2009

Abstract Ultrasound Biomicroscopy is a newly developed high resolution imaging method that uses high frequency ultrasound (50–100 MHz). Tissue penetration is about 4 mm. This method allows detailed observation of anterior and posterior chamber anatomy in the living eye, and is thus a useful tool in both clinical assessment of glaucoma, and research into causes of various glaucoma types.
Diagnosis and treatment control of choroidal melanomas ‐ the role of B‐scan and Doppler‐technique
Authors: Guthoff R. , Winkler P. , Helmke K. , Berger R.
Published: May 2009

Abstract B‐scan guided pulsed Doppler ultrasonography was applied in 62 patients with unilateral malignant melanoma. Prior to radiotherapy Doppler frequency shifts were detected in all but one neoplasm. The average systolic tumour blood flow velocity was recorded as 18.8 ± 7.6 cm/s. Frequency shifts after radiotherapy are described. Probably the methods will find a place in the evaluation of indeterminate fundus lesions and in the follow‐up of irradiated ocular melanomas.
Estimation of blood flow in the carotid artery and intraorbital ophthalmic artery by color pulse Doppler ultrasonography
Authors: Tane Sadanao , Hashimoto Takemitsu
Published: May 2009

Abstract Blood flow velocity was estimated in the orbital part of the ophthalmic artery and in the carotid artery, by way of pulse Doppler utrasonography. The equipment was a Toshiba SSA‐270A machine. The material comprised 12 glaucoma patients (20 eyes, all with open angles) under saticfactory IOP control, mean age 52 years, and 28 healthy controls (mean age 40 years; 54 eyes). Systolic flow velocities of 46 cm/sec and 103 cm/sec, in the ophthalmic and carotid artery respectively, were found in the normal subjects. With mean values of 42 and 116 cm/sec in the glaucoma group there was no significant difference between groups. The same applied to the average flow velocities. A considerable interindividual variation was found.
Dopplersonographic pulse curve analysis for estimation of the haemodynamic function
Authors: Millner R. , Cobet U. , Schobeß H. , Scharff R. , Möbius R.
Published: May 2009

Abstract Experience with Doppler sonographic pulse curve analysis is given from 40 glaucoma patients (examination of the temporal posterior ciliary artery), and from premature babies (blood flow in the anterior cerebral artery). In the latter group the reaction to pain and stress connected with blood sampling was studied. In the glaucoma patients focus was on the influence of IOP level on vascular autoregulation, and the possible response to therapy with beta‐blockers. ‐ Describing an averaging technique, methodological problems are discussed as relevant for the detection of changes in flow and velocity in small blood vessels.
Orbital tumours ‐ the importance of standardized echography
Authors: Hasenfratz G.
Published: May 2009

Abstract In a survey the diagnostic usefulness of standardized echography in orbital disease is demonstrated. Considering differential diagnoses it is stressed that ultrasonically determined location and size of the orbital lesion will not do alone. The main object is to achieve a specific diagnosis by way of tissue differentiation. The method is based on standardized A‐scan supplemented by contact B‐scan and Doppler sonography. Middle and posterior orbit is examined by transocular techniques. A paraocular approach is used for more anterior lesions. From personal experience from more than 300 orbital tumours examples are forwarded illustrating quantitative echography (internal structure, reflectivity, sound attenuation), topographic echography (borders, shape, location), and kinetic echography (consistency, mobility, vascularity). The combination of all nine criteria gives important guidelines concerning the specific lesions met in the orbit and paraorbital regions. The correlation between acoustic and histopathological features is stressed.
An unusual ophthalmic tumour in a 5‐year‐old boy
Authors: Jensen Jørgen Elmo , Fledelius Hans C. , Prause Jan U. , Scherfig Erik
Published: May 2009

Abstract A rare tumour in a 5‐year‐old boy is presented and discussed. In time and location the story had two parts (Fig. 1): 1) a conjunctival granuloma at the nasal limbus of the right eye was surgically removed. 2) a few months later a huge lesion presented in the posterior segment of the same eye. Was it an ocular tumour with extension to the orbit or an orbital process with impression or invasion of the eye? Repeated surgical biopsies have indicated nodular scleritis of the posterior eye segment as the definitive diagnosis.
Visually imparing ROP in children born in Sweden 1975–89
Authors: Jacobson Lena , Stenström Ingeborg
Published: May 2009

Abstract. Among all children registered at the two educational resource centres in Sweden for visually impaired, we found 61 children with ROP causing their visual dysfunction, born 1975–89. Six children had a birth‐weight exceeding 1460 g, four of these were educationally blind. Sixty children had a gestational age of 30 weeks or less, one child had a gestational age of 31 weeks. Forty‐one children had a visual acuity ≤0.05 while 20 had visual acuity of 0.06–0.3 in the best eye. Twenty‐four children had additional handicaps. Seven blind children had developed autistic features. Vitreoretinal surgery had been performed in 27 children. When the retina preoperatively was totally detached surgery failed to restore useful vision. We conclude that it is safer to define the riskgroup for ROP by gestational age than by birth‐weight. If the retina already is totally detached it seems advisable to refrain from vitreoretinal surgery.
Frequency and natural history of retinopathy of prematurity (ROP)
Authors: Maly Eva
Published: May 2009

Abstract. Frequency and natural history of retinopathy of prematurity (ROP) were prospectively studied in 142 preterm infants with birth weight (BW) less than 1501 g and/or gestational age (GA) below 33 weeks, who were born in Malmö 1986–1990. ROP developed in 27 (19%) of the 142 infants. The frequency of the ROP was significantly higher in infants with BW ≤ 1000 g (54%) and in those with GA ≤ 28 weeks (40%) than above these values. Infants with ROP had, compared with those without ROP, significantly lower BW, lower GA, lower Apgar score at 1 and 5 min, longer period of oxygen‐therapy and higher frequency of neonatal complications. Five infants with stage 3 ROP were treated with cryotherapy; four with moderate changes showed good regression, the fifth with a severe stage 3 progressed and became blind. Up to 5 years follow‐up revealed a significantly higher frequency of strabismus (40% vs 8%), myopia (25% vs 4%), and amblyopia (33% vs 6%) in infants with ROP than in those without ROP. Astigmatism and anisometropia were also frequent in children with ROP.
Retinopathy of prematurity in southern Finland
Authors: Lappi Marjatta
Published: May 2009

Abstract. 138 premature infants born 1989–1991 have been examined by the ophthalmologist in Children's Hospital, University of Helsinki. The mean gestational age was 27.3 weeks and the mean birth weight 986 grams. Twenty‐four cases of ROP were found. Seven of them got cryocoagulation treatment in both eyes for ROP 3 with plus disease. Only one child became blind. The risk to get ROP was 17.4% in the whole material and was highest among the most immature infants. The cryocoagulation treatment appeared an effective therapy to prevent blindness.
Very pre‐term birth and visual impairment
Authors: Fledelius Hans C , Greisen Gorm
Published: May 2009

Abstract. In a group of infants and children of very preterm delivery (gestational age 30 weeks or less, n = 411, Rigshospitalet Copenhagen 1983–89) 13 got blind due to retinopathy of prematurity (3.2%) while another 13 with sequelae retained useful vision of at least one eye. One child later acquired bilateral retinoblastoma, with a free interval of one year from a protracted course of ROP stage 2–3 eventually to regress. The 411 surviving subjects being recruited from a total of 515 of a similarly low gestational age, the survival rate in the 7‐year period under study was just below 80%. No doubt, the high survival rate in this very pre‐term group is of importance for the risk of developing retinopathy of prematurity, but the role of the ophthalmologist in controlling the infants is also emphasized. Generally, stricter observation schemes are recommended. ‐ Probably, the ROP frequency in the sample of 23.6% is an underestimate.
Results of cryotherapy for retinopathy of prematurity
Authors: Algvere Peep
Published: May 2009

Abstract. Results are presented from a case material of 22 prematurely born infants (43 eyes) who received cryotherapy for retinopathy of prematurity (ROP); 20 eyes were treated at stage 3, 14 at stage 3 plus, and nine at stage 4 A. Follow‐up examinations at the age of 26 to 52 months (average 38 months) showed regression of ROP in all eyes and visual acuities of 6/60 or better. The timing of cryotherapy is discussed. The present experience indicates treatment earlier than recommended by the US Cryoptherapy of Retinopathy of Prematurity Study Group. There are, as yet, no reliable clinical criteria that can predict which eyes will progress from stage 3 to stages 4 or 5 (tractional retinal detachment or retrolental fibroplasia). Hence, infants at risk should be repeatedly examined and a progression towards impending retinal detachment diagnosed.
Three-Dimensional Simulation of Gas Flow in Microducts
Authors: Agrawal Abhishek , Agrawal Amit
Published: May 2009

Three-dimensional lattice Boltzmann method based simulations of a microduct have been undertaken in this paper. The objective is to understand the different physical phenomena occurring at these small scales and to investigate when the flow can be treated as two-dimensional. Towards this end, the Knudsen number and aspect ratio (depth to width ratio) are varied for a fixed pressure ratio. The pressure in the microduct is non-linear with the non-linearity in pressure reducing with an increase in Knudsen number. The pressure and velocity behaves somewhat similar to two-dimensional microchannels even when the aspect ratio is unity. The slip velocity at the impenetrable wall has two components: along and perpendicular to the flow. Our results show that the streamwise velocity near the centerline is relatively invariant along the depth for aspect ratio more than three, suggesting that the microduct can be modeled as a two-dimensional microchannel. However, the velocity component along the depth is never identically zero, implying that the flow is not truly two-dimensional. A curious change in vector direction in a plane normal to the flow direction is observed around aspect ratio of four. These first set of three-dimensional results are significant because they will help in theoretical development and flow modeling at micro scales.
Modeling and Design of Micro-Grooved Flat Plate Evaporator
Authors: Shikazono Naoki , Suehisa Yasushi , Kasagi Nobuhide , Iwata Hiroshi
Published: May 2009

A micro-grooved flat plate evaporator is modeled and its heat transfer characteristics are investigated numerically and experimentally. A test model is developed for the vapor compression cycle evaporator, where pressure gradient drives the vapor and the liquid flow. In this study, the effect of pressure gradient is implicitly introduced through the Smith’s equation for predicting void fraction from given quality. The film thickness profile in the micro region near the contact line is obtained by solving the 4th order differential equation. Then the local heat flux is obtained by assuming that the heat conduction through the liquid is one dimensional in the wall normal direction. The shape of liquid-vapor interface is assumed to be a circular arc in the macro region, whose radius is directly linked to the void fraction. This curvature radius is used as the boundary condition for the micro region model at the micro-macro interface. Finally, the heat transfer coefficient on a micro-grooved flat plate evaporator is measured in a HFC134a experimental loop and compared with the numerical prediction. The present model assumptions are validated and assessed.
Effect of Operating Pressure on Flow Boiling Heat Transfer in Microchannels
Authors: Bang K. H. , Yoon T. Y.
Published: May 2009

This paper reports an experimental study of flow boiling in a microchannel and this work has been focused on the investigation on the effect of operating pressure. The experimental apparatus consisted mainly of peristaltic pump, preheater, microchannel test tube, and vacuum chamber for control of operating pressure. Deionized water was used as the working fluid. The test section was a round tube of 310 μm inside diameter, made of 304 stainless steel. The experiment has been performed for the conditions of heat flux of 35∼85 kW/m2, mass flux of 200∼300 kg/m2s (160∼250 of liquid Reynolds numbers), and the operating pressure of 10∼20 kPa. The measured flow boiling heat transfer coefficients in the microchannel were in the range of 3.0 to 27 kW/m2K and the experimental data showed that the flow boiling heat transfer coefficients in microchannels were affected mainly by the wall heat flux and the operating pressure.
Spectrographic Microfluidic Memory
Authors: Erickson David , Li Baiyang , Adleman James R. , Vyawahare Saurabh , Quake Stephen , Psaltis Demetri
Published: May 2009

Recent advancements in micro- and nanoscale fluidic manipulation have enabled the development of a new class of tunable optical structures which are collectively referred to as optofluidic devices. In this paper we will introduce our recent work directed towards the development of a spectrographic optofluidic memory. Data encoding for the memory is based on creating spectrographic codes consisting of multiple species of photoluminescent nanoparticles at discrete intensity levels which are suspended in liquids. The data cocktails are mixed, delivered and stored using a series of soft and hard-lithography microfluidic structures. Semiconductor quantum dots are ideally suited for this application due to their narrow and size tunable emission spectra and consistent excitation wavelength. Both pressure driven and electrokinetic approaches to spectral code writing have been developed and will be experimentally demonstrated here. Novel techniques for data storage and readout are also discussed and demonstrated.
Photoelectric‐enhanced radiation therapy with quasi‐monochromatic computed tomography
Authors: Jost Gregor , Mensing Tristan , Golfier Sven , Lawaczeck Rüdiger , Pietsch Hubertus , Hütter Joachim , Cibik Levent , Gerlach Martin , Krumrey Michael , Fratzscher Daniel , Arkadiev Vladimir , Wedell Reiner , Haschke Michael , Langhoff Norbert , Wust Peter , Lüdemann Lutz
Published: May 2009

Photoelectric‐enhanced radiation therapy is a bimodal therapy, consisting of the administration of highly radiation‐absorbing substances into the tumor area and localized regional irradiation with orthovoltage x‐rays. Irradiation can be performed by a modified computed tomography (CT) unit equipped with an additional x‐ray optical module which converts the polychromatic, fan‐shaped CT beam into a monochromatized and focused beam for energy‐tuned photoelectric‐enhanced radiotherapy. A dedicated x‐ray optical module designed for spatial collimation, focusing, and monochromatization was mounted at the exit of the x‐ray tube of a clinical CT unit. Spectrally resolved measurements of the resulting beam were performed using an energy‐dispersive detection system calibrated by synchrotron radiation. The spatial photon fluence was determined by film dosimetry. Depth‐dose measurements were performed and compared to the polychromatic CT and a therapeutic 6 MV beam. The spatial dose distribution in phantoms using a rotating radiation source (quasi‐monochromatic CT and 6 MV, respectively) was investigated by gel dosimetry. The photoelectric dose enhancement for an iodine fraction of 1% in tissue was calculated and verified experimentally. The x‐ray optical module selectively filters the energy of the tungsten emission line with an FWHM of 5 keV. The relative photon fluence distribution demonstrates the focusing characteristic of the x‐ray optical module. A beam width of about 3 mm was determined at the isocenter of the CT gantry. The depth‐dose measurements resulted in a half‐depth value of approximately 36 mm for the CT beams (quasi‐monochromatic, polychromatic) compared to 154 mm for the 6 MV beam. The rotation of the radiation source leads to a steep dose gradient at the center of rotation; the gel dosimetry yields an entrance‐to‐peak dose ratio of 1:10.8 for the quasi‐monochromatic CT and 1:37.3 for a 6 MV beam of the same size. The photoelectric dose enhancement factor increases from 2.2 to 2.4 by using quasi‐monochromatic instead of polychromatic radiation. An additional increase in the radiation dose by a factor of 1.4 due to the focusing characteristic of the x‐ray optical module was calculated. Photoelectric‐enhanced radiation therapy based on a clinical CT unit combined with an x‐ray optical module is a novel therapy option in radiation oncology. The optimized quasi‐monochromatic radiation is strongly focused and ensures high photoelectric dose enhancement for iodine.
Development and validation of a new guidance device for lateral approach stereotactic breast biopsy
Authors: Ma K. , Kornecki A. , Bax J. , Mundt Y. , Fenster A.
Published: May 2009

Stereotactic breast biopsy (SBB) is the gold standard for minimally invasive breast cancer diagnosis. Current systems rely on one of two methods for needle insertion: A vertical approach (perpendicular to the breast compression plate) or a lateral approach (parallel to the compression plate). While the vertical approach is more frequently used, it is not feasible in patients with thin breasts ( thick after compression) or with superficial lesions. Further, existing SBB guidance hardware provides at most one degree of rotational freedom in the needle trajectory, and as such requires a separate skin incision for each biopsy target. The authors present a new design of lateral guidance device for SBB, which addresses the limitations of the vertical approach and provides improvements over the existing lateral guidance hardware. Specifically, the new device provides (1) an adjustable rigid needle support to minimize needle deflection within the breast and (2) an additional degree of rotational freedom in the needle trajectory, allowing the radiologist to sample multiple targets through a single skin incision. This device was compared to a commercial lateral guidance device in a series of phantom experiments. Needle placement error using each device was measured in agar phantoms for needle insertions at lateral depths of 2 and 5 cm. The biopsy success rate for each device was then estimated by performing biopsy procedures in commercial SBB phantoms. SBB performed with the new lateral guidance device provided reduced needle placement error relative to the commercial lateral guidance device ( vs for targets at 2 cm depth; vs for targets at 5 cm depth). The new lateral guidance device also provided improved biopsy accuracy in SBB procedures compared to the commercial lateral guidance device (100% vs 58% success rate). Finally, experiments were performed to demonstrate that the new device can accurately sample lesions within thin breast phantoms and multiple lesions through a single incision point. This device can be incorporated directly into the clinical SBB procedural workflow, with no additional electrical hardware, software, postprocessing, or image analysis.
Assessment of Undiscovered Oil and Gas in the Arctic
Authors: Gautier Donald L. , Bird Kenneth J. , Charpentier Ronald R. , Grantz Arthur , Houseknecht David W. , Klett Timothy R. , Moore Thomas E. , Pitman Janet K. , Schenk Christopher J. , Schuenemeyer John H. , Sørensen Kai , Tennyson Marilyn E. , Valin Zenon C. , Wandrey Craig J.
Published: May 2009

Arctic Energy Reserves

The Arctic consists of approximately equal fractions of terrain above sea level, continental shelves with depths less than 500 meters, and deep ocean basins that have been mostly covered in ice. While the deep ocean regions probably have limited petroleum reserves, the shelf areas are likely to contain abundant ones. Based on the limited amount of exploration data available,

Gautier
et al.

(p.
1175
) have constructed a probabilistic, geology-based estimate of how much oil and gas may be found. Approximately 30% of the world's undiscovered gas, and 13% of its undiscovered oil, may be found north of the Arctic Circle. Advances in the technology of hydrocarbon recovery, as well as vanishing ice cover around the North Pole, make the Arctic an increasingly attractive region for energy source development, although the existing reserves are probably not large enough to shift current production patterns significantly.
Unstable Tandem Repeats in Promoters Confer Transcriptional Evolvability
Authors: Vinces Marcelo D. , Legendre Matthieu , Caldara Marina , Hagihara Masaki , Verstrepen Kevin J.
Published: May 2009

Genotype, Phenotype, and Variation

Phenotypic evolution results from changes in coding sequences, as well as in regulatory regions of the genome.

Vinces
et al.

(p.
1213
) uncover an abundant source of gene expression variability in the promoters of
Saccharomyces cerevisiae
genes. Up to 25% of yeast promoter regions contain a highly variable tandem repeat sequence, which effect gene expression and local chromatin structure. The intrinsic instability of these repeats generates variability in gene expression levels and provides a mechanism for rapid evolution of phenotypic traits.