bluuebunny/crossref_metadata_2025 huggingface dataset:
Ocular anaphylaxis induced in the rat by topical application of compound 48/80
Authors: Allansmith Mathea R. , Baird Robert S. , Ross Robert N. , Barney Neal P. , Bloch Kurt J.
Published: May 2009

AbstractIn the present study we sought to develop a model of ocular anaphylaxis based on the topical application of compound 48/80 to the surface of the rat eye. Doses ranging from 50 to 1000 μg were found to produce graded edema of the conjunctiva and swelling of the lid. On histologic examination, 50 μm compound 48/80 produced no changes distinguishable from those in PBS‐treated controls, 150 μm produced mild alterations, and 250, 500, and 1000 μg compound 48/80 produced a marked increase in degranulated mast cells and a mild influx of neutrophils. The time course of the response to 250 μg and 1000 μg of compound 48/80 was evaluated over a 72‐h period. Both doses elicited epithelial damage. A mild reduction in the number of mast cell was seen at 6 h in rats receiving 250 or 1000 μg. The reduction persisted to 72 h in rats receiving 1000 μg. The number of neutrophils was increased at 1 and 6 h in eyes treated with 250 (ig and at 1,6, and 24 h in eyes treated with 1000 [ig compound 48/80. The clinical and histologic changes induced by application of 250 jig compound 48/80 resemble those seen in patients with allergic conjunctivitis suggesting that a model of ocular anaphylaxis based on the topical application compound 48/80 will be clinically relevant and experimentally practical.
Development of the gas‐permeable impression‐moulded scleral contact lens
Authors: Lyons C. J. , Buckley R. J. , Pullum K. , Sapp N.
Published: May 2009

Abstract Although superceded by corneal hard and soft contact lenses for the correction of simple refractive error, the scleral lens still has numerous medical applications in modern ophthamological practice. However, a major problem with scleral lenses has been the limited wearing time due to corneal occlusion and consequent hypoxia. We present two alternative methods for the production of moulded gas permeable scleral contact lenses.
Lectin receptors of normal and dystrophic corneas
Authors: Panjwani Noorjahan , Baum Jules
Published: May 2009

Abstract In recent years, our laboratory has used lectins to detect carbohydrate‐related abnormalities in dystrophic corneas and species‐specific differences in the carbohydrates of normal corneas. These studies have: 1) demonstrated that abnormal glycoconjugates are present in corneas with macular and lattice dystrophy, 2) provided additional means of differentiating corneas with macular, lattice and granular dystrophy, 3) demonstrated that distinct species‐specific differences are present in the glycoconjugates of normal corneas and 4) provided guidelines for the selection of an animal model for the study of corneal glycoconjugates.
Keratoconus associated with Terrien's marginal degeneration
Authors: Pouliquen Y. , Renard G. , Savoldelli M.
Published: May 2009

Abstract A 59‐year‐old man presented with Terrien's marginal degeneration associated with keratoconus of his left eye. Penetrating keratoplasty of the left eye permitted an evaluation under optical microscopy, as well as transmission and scanning electron microscopy. An anatomical‐pathological evaluation confirmed the co‐existence of a central lesion due to keratoconus and a peripheral lesion due to Terrien's marginal degeneration. An absence of the knowledge of the etiology of either afflication does not allow one to define whether there exists one or two active degenerative processes.
Congenital corneal keloid
Authors: Weiner Mark J. , Albert Daniel M.
Published: May 2009

Abstract The clinical course and pathological findings in an infant with a congenital corneal opacity, aniridia, and cataract of the right eye and anophthalmia of the left orbit are reviewed. Although the lesion was thought to represent a dermoid pre‐operatively, the keratoplasty specimen revealed disorganized and vascularized connective tissue, with thickened, keratinized epithelium. Bowman's and Descemet's membranes as well as the endothelium were absent. These histopathologic findings were felt to represent a congenital corneal keloid. The co‐existence of aniridia in the involved eye and anophthalmia of the contralateral socket are hypothesized to be evidence that a primary ocular developmental disorder, rather than a reparative process, resulted in the corneal alteration. The difficulties of penetrating keratoplasty in lesions of this sort are examined.
Iris as a source of cells on the intraocular lens surface
Authors: Blomstedt Göran , Gallo Juan , Fagerholm Per
Published: May 2009

Abstract A tissue culture model is presented where strips of humanirides were glued (Tesseel®) onto a PMMA intraocular lens (IOL). The preparations were followed for 21 days in the phase contrast microscope and subsequently prepared for scanning electron microscopy. Cells of two types readily grew onto the PMMA surface. Fibroblastlike cells formed aproteinaceous membrane covering the IOL surface whereas pigment containing epitheloid cells sometimes formed cellular aggregates similar to precipitates found in vivo on the IOL surface.
An analysis of cataract surgery outcome by a PC computer program
Authors: Storr‐Paulsen Allan , Larsen Michael
Published: May 2009

Abstract Cataract surgery is the most common operation in ophthalmology.

New techniques and matarials have come very quickly and have introduced a great number of factors which may all influence the outcome in a good or bad direction. A systematic computerised analysis of data from the surgical records will provide us with the possibility of analysing the different factors which affect the results of surgery.

In a pilot study we evaluated the benefit of using a computer program to analyse up to 150 preoperative, operative and postoperative clinical parameters from each patient.

The purpose of the study was 1) a registration of the number of cataract operations in the department, 2) a possibility to analyse the results of different patients groups, 3) a possibility to analyse the surgical outcome by different surgeons and 4) based upon the computer analysed data to improve current surgery and introduce new surgical procedures.

In the present paper the results of the surgery itself are not so important, rather we will focuse on the possibilities of the computer program to retrieve, analyse and present the results in tables or graphs.

The program provides a convenient approach to the rational evaluation of a surgical procedure and a means for constantly improving its quality.
A randomized prospective clinical comparison of hema (IOGEL®) and PMMA intraocular lenses
Authors: Sveinsson Örn , Seland Johan
Published: May 2009

ABSTRACT The aim of this prospective study was to compare the clinical efficiency of two different kinds of intraocular lenses. By randomization, 40 patients received an intraocular lens either made of HEMA (hydroxyethylmethacrylate) or PMMA (Polymethylmethacrylate). 20 patients were assigned to each group. Age varied from 60 to 79 years. Follow up periode was 12 months. Posterior synechiae were more frequent in the PMMA group. This was statistically significant. One week postoperatively slightly more intraocular reaction was observed in the HEMA group. On the other hand PMMA lenses had higher incidence of precipitates. These differences however were not found to be statistically significant The analysis showed no difference in the visual acuity ratings in the groups at 12 months (VA 6/9 or better in 95%). Our conclusion is that the soft HEMA lens is a safe alternative to the rigid PMMA lens and probably more biocompatible to the eye.
Peripheral cataracts and trinitrotoluene exposure
Authors: Teir Henrik , Grenquist‐Nordén Brita
Published: May 2009

Abstract Peripheral cataracts in 12 workers with long‐term occupational trinitrotoluene exposure were studied in a follow‐up period of 5 years. The exposure was considered low and the measured concentration of trinitrotoluene in the breathing zone was maximally 0.3 mg/m3, which is below the current Finnish threshold limit value. Peripheral ringlike lens opacities were found in all workers, but during the follow‐up time progression was none or minimal. The peripheral opacities were best seen and cocumented with lateral gaze. The severity of peripheral opacities correleted with exposure times. The opacities were irreversible in subjects without exposure for 5 years, but did not affect visual acuity.
Two year follow‐up of epikeratophakia for keratoconus
Authors: Uusitalo Risto J. , Lehtosalo Juha , Klyce Stephen D.
Published: May 2009

Abstract Fifty‐three epikeratophakia procedures were peformed on 50 patients with keratocouns. Of the 53 surgical procedures and 3 re‐operations performed, 88.7% were anatomically successful. Three falled grafts were replaced successfully; in all, 94% of the patients had anatomically successful grafts. Forty one patients have been followed for more than 12 months and in 10 patients the follow‐up extended to over 2 years. There was a significant improvement in the mean preoperative to postoperative uncorrected visual acuity. At 1 and 2 years postoperatively, the best corrected visual acuities all returned to within one line of their preoperative best corrected acuity; in more than 80%, acuities were 20/40 or better. The mean flattening by keratometry readings was 8.5 diopters (D) and the mean decrease in myopia in terms of spherical aquivalent was 4.0 D. One case report is presented to show in detail the topographical changes induced by epikeratophakia in keratoconus. A group of patients with advanced keratoconus who did not meet the entry criteria of the nationwide study (USA) also underwent epikeratophakia. The broadening of the indications to more advanced cases of keratoconus was shown to result in less satisfactory visual outcome and more complications.
Goniodysgenesis and exfoliation syndrome—significant concepts in therapy of hypertensive open angle glaucoma (HOAG)
Authors: Jerndal Tord
Published: May 2009

Abstract HOAG is caused by certain factors that reduce the aqueous outflow and cause elevated IOP and subsequent glaucoma.

The problem: To find the eyes predisposed to OH and glaucoma early enough.

What ocular signs are useful as early indicators of OH?

Gonioscopic studies have demonstrated that dominat goniodysgenesis is the genetic trait responsible for hereditary glaucoma, a hypertensive glaucoma with its onset usually before 50 years of age. For this group of patients early diagnosis is extremely important because of their lengthy exposition to OH. In a personal mixed surgical material of 281 hypertensive patients with a mean age of 65 years, goniodysgenesis was present in 55%.

Other studies from Sweden demonstrate that exfoliation syndrome (ES) is found in 3/4 of all patients with open angle glaucoma. Late and inefficient therapy was a common cause of severe field defects in the exfoliative cases.
The ‘Lava sign’ in pigmentary glaucoma
Authors: Petursson Gissur
Published: May 2009

Abstract Pigmentary glaucoma has typical characteristics that distinguish it as a separate entity. Excessive accumulation of pigment in the inferior chamber angle, sufficient to roll up on the corneal endothelium in downward gaze is very rare indeed, in this glaucoma group.

This article will report on one such case along with it's management.

Pigmentary hypopyon or hyphema and black hypopyon 2,3,4,5 or hyphema are terms that have been used loosely to describe the condition.

As hypopyon and hyphema apply to different conditions in the eye, it is proposed that this rare phenomenon be referred to as the “lava sign”.
Cryotherapy for malignancies of the eyelid
Authors: Tuppurainen Kaija
Published: May 2009

Abstract Results have been published on the cryotherapy of basal cell carcinoma in the eyelid since the 1960s. The recovery rates vary from 82 to 97 percent, depending on the size and histological type of the tumour and on whether the tumour is a recurrence. In this article, the results of the cryotherapy of 88 cutaneus malignancies in the eyelid or its immediate vicinity are presented. The follow‐up time was rather short, 24 months on the average. The recurrence rate for the whole material was 9.1%. The functional and cosmetic results were satisfactory: no epiphora problems occurred after the treatment, even though 51.4% of the eyelid tumours were nasal. In one case, a difficult ectropion had to be surgically corrected after the cryotherapy; surgical treatment was likewise required for conjunctival hyperplasia in three cases.
Clinical assessment of contrast sensitivity
Authors: Hyvärinen Lea , Moilanen IIkka , Rovamo Jyrki , Näsänen Risto
Published: May 2009

Visual system transfers information at both high and low contrastlevels. It has been customary to assess visual function by measuring visual acuity although it has been well documented for over ten years' time that measurement of contrast sensitivity may reveal loss of visual function that is not detected by measurement of visual acuity.

There are several commercially available clinical tests that are used in Scandinavian countries for assessment of visual transfer function in low contrast domain. We have chosen six of them for comparison: Cambridge Low Contrast Gratings, Vistech's contrast sensitivity tests for distance and near, PelliåRobson's low contrast letter chart, Vistest's LH‐5 contrast visual acuity test, and Mentor's computer based device for measurement of both contrast sensitivity and low contrast visual acuity.

Each of the commercial tests measures low contrast vision in slightly different way. In order to have an overview of the function of these tests we have assessed vision of visually impaired patients and normally sighted subjects using all tests during one visit. In general the grating tests result inslightly higher contrast sensitivity values than the optotype tests. Contrast sensitivity values measured with grating tests are difficult to assess because the size of the stimulus affects the values.

Based on our results, we recommend assessment of low contrast visual transfer using an optotype test as the basic test and a grating test in order to assess vision for orientation and mobility. The grating test should be used at two different distances resulting in approximately two and ten degree stimuli.
MOLECULAR AND CELLULAR RESPONSES OF THE CORNEAL EPITHELIUM TO WOUND HEALING
Authors: Beuerman Roger W. , Thompson Hilary W.
Published: May 2009

Abstract The corneal epithelium responds rapidly to injury, repairing defects with a layer of cells that covers the denuded corneal surface and prevents infection and loss of vision. After a wound, reorganization of the remaining epithelial cells occurs over several hours, resulting in the formation of a migratory leading edge. However, expression of genes such as c‐fos occurs within minutes of wounding. This early expression may be important for directing epithelial reorganization and the later mitotic burst. Our results show that receptors for epidermal growth factor are upregulated in the migratory cell population. Proliferation through a mitotic burst was observed in cells surrounding the original wound margin after 36 hours. The interaction between gene expression and cell surface receptors for growth factors and cell proliferation suggests that wound healing occurs in a complex, but tightly controlled process in the corneal epithelium.
COLLAGENOLYTIC/GELATINOLYTIC ENZYMES IN CORNEAL WOUND HEALING
Authors: Fini M. Elizabeth , Girard Marie T. , Matsubara Masao
Published: May 2009

Abstract We have documented changes in expression of collagenolytic/gelatinolytic enzymes of the matrix metalloproteinase family (MMP) in healing or ulcerating corneal wounds of rat or rabbit. Correlation of our findings with specific changes in the extracellular matrix of the repair tissue suggests two different roles for the enzymes, MMP‐2 and MMP‐9. MMP‐2 is expressed in undamaged corneal stroma where it may degrade the occasional collagen molecule that becomes damaged. After corneal wounding, expression of this enzyme is increased and much of it appears in the active form. These changes persist for at least seven months, suggesting that MMP‐2 is involved in the prolonged process of collagen remodelling in the stromal repair tissue. MMP‐9 is expressed in the epithelial layer of repair tissue with a timing suggesting it might participate in controlling resynthesis of the basement membrane. MMP‐9 also appears to be involved in degradation of the epithelial basement membrane that precedes corneal ulceration.
CLINICAL MEASURES TO PROMOTE CORNEAL EPITHELIAL HEALING
Authors: Pfister Roswell R.
Published: May 2009

Abstract It is necessary to know the specific patho‐biology of a persistent epithelial defect to determine the strategy to be employed to assist in its repair. Lid position and function must be normal and any deficiency in the quantity and quality of the tears enhanced by tear preparations and closure of the lacrimal canaliculi. Adverse drug effects must be eliminated. Multiple corneal punctures and excision of reduplicated basal lamina have virtually eliminated the problem of recurrent corneal erosions. Control of any inflammatory process also speeds healing. Vitamin supplements, especially A, reverse defects associated with xeroph‐thalmalia. In any of these diseases, mechanical treatments consisting of soft contact lenses for persistent epithelial defects and collagen shields for the delivery of antibiotics or steoids to the eye may be employed. Tarsorraphy relieves the problem of persistent epithelial defects in neurotrophic keratitis and a variety of other conditions characterized by persistent surface breakdown. Preliminary data from open label studies of epidermal growth factors and fibronectin are encouraging but not yet conclusive.
SURGICAL APPROACHES TO CORNEAL WOUND HEALING
Authors: Kaufman Herbert E.
Published: May 2009

Abstract New approaches to improving corneal epithelial wound healing include stromal puncture and removal of abnormal basement membrane material by excimer laser ablation (phototherapeutic keratectomy). Non‐healing corneal erosions and chemical burns may also benefit from laser excision of the damaged surface to permit more normal epithelial attachments. Reduction of postsurgical astigmatism may be facilitated by adjustable sutures after penetrating keratoplasty or by molding the cornea with the use of a rigid contact lens in the immediate postoperative period.
The lens capsule and zonulae
Authors: Seland Johan H.
Published: May 2009

Abstract The embryology and natural history of the lens capsule and the zonular apparatus have been described according to the present knowledge of the subject. Clinical evidence pointing towards an active turnover of lens capsule material is presented.
Secondary cataract
Authors: Lundgren Björn , Jonsson Eva , Rolfsen Wenche
Published: May 2009

Abstract Secondary cataract formation is the most common postoperative complication following cataract surgery. To study different methods preventing the secondary cataract formation a relevant animal model is required. An in vivo rabbit model for studies on the prevention of secondary cataract formation is presented. The lens nucleus and cortex were removed by phacoemulsification, and two months later the growth of the secondary cataract was estimated by scoring on a scale from 0–4, both central and peripheral, and by measuring the wet mass of the dissected secondary cataract. The model seems to be a relevant way to study different concepts for the prevention of secondary cataract formation.
Adhesion and junction molecules in embryonic and adult lens cell differentiation
Authors: Watanabe Michiko , Kobayashi Hideyuki , Yao Ruihong , Maisel Harry
Published: May 2009

Abstract The expression of the neural cell adhesion molecule NCAM and its polysialic acid (PSA) moiety was documented during embryonic development and adult differentiation of chicken lens cells. In both the embryo and adult, NCAM is predominantly found in the epithelium and the zone of young elongating cells of the annular pad. NCAM abundance drops markedly in the cortical fibers and is further reduced in the lens nucleus. Epithelial cell NCAM is more highly polysialylated in the adult than in the embryonic lens. Three isoforms of NCAM at 180, 140, and 120 kDa were detected in the lens and predominantly associated with the unit membrane‐enriched plasma membranes of fiber cells. The distribution of NCAM relative to MP26 and the adherence junction‐associated glycoprotein N‐cadherin suggests that NCAM could influence the formation of fiber cell gap junctions and adherence junctions.
The control of lens growth: Relationship to secondary cataract
Authors: Beebe David C.
Published: May 2009

Abstract A lens growth factor was identified that is present in the anterior chamber of the embryonic chicken eye. The mitogen is similar to an embryo‐specific activity found in embryo serum. Several purified growth factors, applied singly or in combination, did not stimulate cell division in embryonic lens cells. The serum mitogen is a protein which does not bind to heparin‐Sepharose. The possibility is presented that the lens epithelium contains two distinct cell types, the proliferating cells of the germinative zone and the mitotically quiescent central epithelial cells. It is proposed that only cells in the germinative zone are capable of responding to normal lens growth factors. It is likely, therefore, that these cells present the greatest risk for secondary cataract formation.
Reactive formation of hyaluronic acid after small and large lens injury
Authors: Fagerholm Per , Fitzsimmons Thomas , Härfstrand Anders , Schenholm Mona
Published: May 2009

Abstract The reactive production of hyaluronic acid was studied in the rabbit lens following a 4 mm in diameter anterior lens wound, and following a large lens wound (extracapsular cataract extraction). Furthermore, human post‐mortem after‐cataract specimen were also studied. The hyaluronic acid was localized histochemically using a new specific technique. Hyaluronic acid in the small wound was localized in the primary sealing plug that precedes the reepithelialization and new capsule formation. In the large wound hyaluronic acid was found around the cells proliferating on the posterior capsule. The same was true in the human after‐cataract specimen. It was concluded that the primary wound sealing and the posterior capsule cellular outgrowth constitute similar cellular responses.
Pre‐term delivery and the growth of the eye An oculometric study of eye size around term‐time
Authors: Fledelius H.C.
Published: May 2009

Abstract Refraction and axial eye dimensions, evaluated by ultrasound measurements, were investigated in 101 pre‐term infants and 25 full‐term controls. Gestational ages in the pre‐term group ranged from 25 to 34 weeks, birth weights from 728 to 2480 g. All were seen in the eye clinic due to risk of developing retinopathy of prematurity. Age at examination was 36–54 weeks (gestational/conceptional) in the pre‐terms and 37.3–50 weeks in the term infants. Adjusted to a 40 weeks axial length value (based on an assumed avarage eye elongation of 0.14 mm per week) the term‐values were similar, 17.02 and 17.03 mm in the two groups. Within the premature group, however, the 40‐week ajusted axial lengths were shorter, the shorter the gestational age. The study demonstrated more foetal anterior segment proportions, with flatter anterior chambers and thicker, more spheroid lenses in the preterm infants. Probably this explains the early preponderance of myopia in that group, at feature eventually to disappear, and not to be confused with myopia of prematurity. As compared to the full‐terms a correlational disturbance by pre‐term delivery was further indicated by the absence of the usual correlation between axial length and refractive value.
The relation between the sagittal and transversal diameters in eyes with retinal detachment
Authors: Eissa W. , Skurczynski M. , Lewandowski P. , Kasprzak J.
Published: May 2009

Abstract Using A‐mode ultrasonography, the axial length and the width (transversal or equatorial diameter) of both eyes ‐ fellow and affected ‐ have been measured in patients with retinal detachment. For comparison, the same measurements have been performed in healthy controls. The patients have been divided into different groups. It was found that there are some changes in the relation between the axial length and the width of the eyes in patients with retinal detachment, according to the comparison with healthy people, in most cases.
Sophisticated instrumentation and ophthalmic ultrasonography
Authors: Buschmann W.
Published: May 2009

Abstract Formerly, ophthalmic ultrasonography was leading in view of high‐performance apparatuses and transducer probes: e.g., the first array‐scanner in the world was built for ophthalmic use. Within the past 2 decades, however, high‐tech innovations were merely developed for other medical specialities. These were studied in view of their use for ultrasonography of eye and orbit. The combination of B‐scan and Doppler techniques facilitates detection of orbital vessels. The resolution of ophthalmic digital B‐scan video images proved poorer than crt‐B‐scans. A digital memory, however, is advantageous. But one high‐resolution crt‐type B‐scan needs more than one disc storage capacity. »Frontline digitalization« could help to reduce the amount of data. ‐ Array transducers are now available in small sizes and could better show structure movements, but they were not yet adapted to ophthalmic use. This applies as well to annular arrays and dynamic focusring. ‐ Different methods of 3‐dimensional scanning and (Pseudo‐) 3‐dimensional imaging might renew Baum's and Coleman's early work.
Ultrasonographic three‐dimensional scanning for determination of intraocular tumour volume
Authors: Jensen Peter Koch
Published: May 2009

Abstract Important prognostic information may be gained from knowing the volume and the rate of growth of intraocular tumours, such as choroidal melanomas. An ultrasonographic 3‐D scanning system based on rotation of a commercial sector scanning transducer applied directly onto a closed eyelid was designed to measure such volume. Control af movement, data acquisition, and image analysis are accomplished by means of a microcomputer and application‐specific software. The elapsed time for scanning and digitizing 20 cross‐sectional images is about 1 sec. Outlines of specific structures are traced manually. The system var tested through repeated measurements of known volumes of meat. The mean variation coefficient of these measurements was 2.8%. The traced volumes were linearly dependent on gain setting of the system requiring a fixed setting for accurate estimates. The procedures of scanning and tracing contributed about equally to the total variance. This method allows repeatable, reliable, and easily generated quantitative measurements of volume with a great potential for use in the diagnosis of malignant tumours and control of the effectiveness of radiotherapy.
Computer simulations of ultrasonic heating for ocular therapy
Authors: Lizzi F. L. , Driller J. , Kalisz A. , Coleman D.J.
Published: May 2009

Abstract Computer simulations are being performed to model the temperature patterns produced during ultrasonically induced hyperthermia of ocular tumours. The software package for these simulations incorporates operator interaction and uses tissue geometry obtained from B‐mode data. Previous studies used geometric approximations for the incident beams used for hyperthermia. In the current study, these beams were computed using diffraction analysis to obtain more realistic simulations of clinical exposures.
Colour Doppler flow imaging of the orbital veins
Authors: Berges O.
Published: May 2009

Abstract Experience is given from 79 orbital lesions examined by Colour Doppler Flow Imaging (CDFI) Dec. 1990 to Febr. 1992. We further examined 167 ocular tumours, or tumourlike lesions, and 32 ophthalmic cases groupes as ‘various’. Here, our experience is summarized concerning the flow patterns demonstrated in orbital veins, pathologic and normal. Adding dynamic and quantitative information to the clinical evaluation CDFI proved superior to conventional B‐ and A‐mode echography. The method is essential in assessing and establishing the diagnosis of low flow dural malformations of the cavernous sinus. Pulsed Doppler appears helpful for the decision of therapy (embolization) and its optimum timing.
Duplex and color Doppler ultrasound in the differential diagnosis of choroidal tumors
Authors: Wolff‐Korman Patricia G. , Kormann Boris A. , Hasenfratz Gerhard C. , Spengel Florentin A.
Published: May 2009

Abstract There is paucity of data on the value of neovascular blood flow measurements in the differential diagnosis of human choroidal tumors, mainly due to difficulties in quantitating tumor vascularity in vivo. Color Doppler imaging and Duplex ultrasound, the combination of B‐mode ultrasound and pulse Doppler analysis, were used to quantify tumor blood flow in 103 untreated tumors of the choroid.

Pulsatile blood flow was detected at the tumor base of 62 choroidal melanomas (tumor height (TH) 3.1–11.7 mm) with a mean peak systolic frequency (MPSF) of 0.98 kHz (range 0.3–2.7 kHz). Compared to melanomas pulsatile neovascular flow in choroidal metastases (TH 2.1–6.5 mm, n = 12) was significantly higher (MPSF 1.87 kHz, range 0.8–3.5 kHz). No Doppler signals were elicited from age‐related macular degeneration (n = 9), choroidal nevus (TH 1.5–2.1 mm, n = 18) and choroidal osteoma (n = 2).

The results indicate that the quantitative measurement of tumor blood flow by duplex and color Doppler ultrasound may serve as a new diagnostic tool in the evaluation of intraocular tumors.
Our experience in the diagnosis of intraocular tumours by a B‐scan computerized system and angiodynography (Doppler). Preliminary results
Authors: Falco Leonardo , Esente Stefano , Fanfani Sandro , Pasarelli Nicola , Utari Sabrina
Published: May 2009

Abstract The authors compare the ultrasound diagnostic results of intraocular tumours by A/B‐scans (Sonomed B 3000, Sonocare, Sonovision STT‐100) with images obtained using computerized B‐scan (Sonocare, Sonovision STT‐100, Acoustic Tissue Typing ATT) and angiodynopgraphy systems (Quantum Philips). The Sonovision uses a computerized ultrasound spectrum analysis to assess the probability that a given lesion is a certain tumour, rather than another. The ATT system provides diagnostic probability for type B and type E melanoma, for haemangioma and metastatic carcinoma.

The Quantum ultrasound equipment was developed for studying the heart and the major blood vessels. It is a colour Doppler that simplifies the Doppler technique, allowing it to study small anatomical parts such as tumourlike lesions of the eye. The Doppler technique ascertains the presence and the velocity of blood flow in the tumours.

In presenting the preliminary results with the new techniques the authors are aware that the ATT system is not designed for some of the lesions under study (melanomas after conservative radiotherapy).
Standardized A‐scan echography and the normal optic nerve Experience with the new Mini A equipment
Authors: Cennamo G. , Rosa N. , La Rana A. , Pastena B.
Published: May 2009

Abstract The potential of making differential diagnosis in optic nerve disease with standardized A‐Scan echography has been well established. With this technique it is possible to differentiate ‘solid’ and ‘fluid’ thickening. A few years ago a new standardized A‐scan equipment was built: The Mini A. With this equipment, it is possible to distinguish spikes coming from the pia, the arachnoid, and the dura around the optic nerve, and to measure the thickness of these structures with a precision of 0.03 mm. We found dura distance 4.0–5.3 mm, arachnoid 3.2–4.0 mm, an pial diameter 2.8–3.4 mm. In this paper the authors discuss their preliminary findings in a normal population.
The retinal pigment epithelium in clinical echography
Authors: Clemens S.
Published: May 2009

Abstract The resolution of the Triscan (Biophysic Medical) and the Cooper‐Alcon 2000 equipments proved sufficient for depicting three separate curvilinear echostructures from the back of the eye. The anatomical counterparts are the inner limiting membrane of the retina, the pigment epithelium, and the inner surface of the sclera. Imaging will be impeded due to sound dispersion if the sound beam is directed through the lens, or via the cornea and the pars plicata of the ciliary body, respectively. The potential of the method is discussed.
Visual impairment due to retinopathy of prematurity in Nordic children
Authors: Riise R. , Flage T. , Hansen E. , Rosenberg T. , Rudanko S.‐L. , Viggosson G.
Published: May 2009

Abstract. The registers of visually impaired children in Denmark, Finland, Iceland and Norway have been compiled into a common database by a Nordic study group of ophthalmologists, NORDSYN. The database contains information on 2527 children aged 0–17 years. The total number of children with visual impairment due to retinopathy of prematurity (ROP) is 247. ROP is the 3rd most common single diagnosis in the database. The age‐specific national prevalence of registration (N/100 000) of visual impariment due to ROP varies from 12 in Denmark to 5 in Finland and Norway and 4 in Iceland. The differences can partly be explained by varying efficiency of registration. The age‐distribution indicates that visual impairment due to ROP is not decreasing. Of the 247 children 175 had a visual acuity less than 1/60 and 58 had one or more additional impairments. Incidence studies on visual impairment in Nordic children are being prepared.
Retinopathy of prematurity 1974–91
Authors: Bech Niels , Fledelius Hans C. , Rosenberg Thomas
Published: May 2009

Abstract. Registration of visual impairment is compulsory in Denmark for the age group 0–17 years. With birth years 1974–91 141 subjects were in the register with retinopathy of prematurity as basic disease, giving a frequency of 13.1 per 100000 liveborn. Compared with other countries this is a high figure, and the trend over the period is a slight annual increase. Further analysing the data for trends in time the material was subdivided chronologically into thirds, each group comprising 47 subjects. Birth weight and gestational age showed a decline: median values in the three groups were 1250, 1100, and 960 g, and 30, 28, and 27 weeks, respectively. Associated CNS handicaps were recorded in 17, 38, and 34%. Visual impairment was serious in all groups, the median corrected acuity of the better eye being below 1/60. Geographically there was a striking shift towards a Copenhagen area preponderance of heavy ROP cases, with one of the two NICUs to account for the main part of registered cases in the most recent period.
Normal and deviant behavior in blind children with ROP
Authors: Janson Ulf
Published: May 2009

Abstract. Congenitally blind children, especially with ROP, are at risk for developing autistic traits. Early behavior risk screening would be of value, but no instruments with acceptable specificity are available. Traditional behavioral symptoms of infantile autism also characterize blind children without autistic disturbance. This report attempts at identifying early behavior patterns that distinguish autistic from non‐autistic blind children with ROP. Developmental data, parents' reports, and video‐recordings are analyzed. It is concluded that observations of developmental delays are not specific enough in screening out the risk group. However, it is possible to describe a behavior pattern, emerging between 12 and 30 months, of unresponsitivity and stereotypic object manipulation, which distinguishes autistic and non‐autistic subjects. This might be a pattern of specific risk behavior in blind children. However, further prospective studies must be performed to test these proportions.
Neonatal care of very low birth weight pre‐term infants in the 1990's in Sweden
Authors: Svenningsen N. W.
Published: May 2009

Abstract. Refinement of optimal neonatal intensive care for the very pre‐term infants with risk of developing neonatal complications including retinopathy of prematurity (ROP) has been under development since the late 1980's. During the last decade better methods for supporting the respiration including surfactant treatment has contributed to the increased survival rate which today is more than 50% for infants born between 24 and 28 completed weeks of gestation. Improvement in the ‘environmental engineering’ in the neonatal intensive care unit is necessary to improve the longterm outcome regarding disabilities and handicaps including ROP. Clinical research in neonatology clearly shows that a high quality medical and nursing care is required for these infants.
ROP in three follow‐up studies from Rigshospitalet during the period 1976–1987
Authors: Greisen Gorm
Published: May 2009

Abstract. Three studies of late outcome in groups of consecutively admitted very low birthweight or very pre‐term infants have recently been reported from Rigshospitalet, Copenhagen. The periods were 1976–78, 1980–82, and 1984–87. The incidences of blindness due to retinopathy of prematurity (ROP) and of motor deficit due to cerebral palsy (CP) are analysed in this report. For the present purpose selection within the three groups made them more, although not entirely, comparable. In spite of marked changes in the use of mechanical ventilation, and in survival rate, the incidences of ROP as well as CP remained constant, at about 5% and 10% of the survivors, respectively. The actual numbers are too small for clearcut conclusions but the analysis supports two previously formed notions: 1) According to monitoring of blood gases deviating oxygen and carbondioxide tensions do not appear as prime factors in inducing neither ROP nor CP, and 2) a very preterm infant of given size and maturity has become less exposed to ROP and CP over the years.
Retinopathy of prematurity in a Danish neonatal intensive care unit, 1985–1991
Authors: Arrøe Mette , Peitersen Birgit
Published: May 2009

Abstract. During the 7 year period 1985 to 1991, 170 infants born in Hvidovre Hospital, Denmark, with birth‐weight ≤ 1500 g and gestational age ≤ 32 completed weeks survived at least 8 weeks or more and had eye examinations carried out. Forty‐five infants had ophthalmoscopic evidence of retinopathy of prematurity (ROP). Eighteen developed blindness or severely reduced vision and 6 developed unilateral blindness. In 21 the ROP changes regressed. Eight infants eventually developed severe myopia. The 45 infants with ROP were compared with the 125 without ROP. There was no difference in birth weight, gender, or mode of delivery. Significant difference was found in gestational age, asphyxia, intensive treatment and complications. Particularly infants with ROP born with gestational age 27 to 29 weeks needed prolonged and more intensive treatment than infants without ROP. Infants with ROP had more frequently long term sequels from the central nervous system than infants without ROP.
Regressed retinopathy of prematurity in children aged 5–10 years
Authors: Gallo Juan E. , Holmström Gerd , Kugelberg Ulla , Hedquist Bo , Lennerstrand Gunnar
Published: May 2009

Abstract. Regressed retinopathy of prematurity (ROP) and its sequelae has been analysed in pre‐term born children with a birth weight < 1500 g and/or < 33 weeks of gestational age, born in Stockholm during 1976–81. At the age of 5–10 years, we found that 134 of 528 preterm born children (25.4%) had been at departments of ophthalmology in Stockholm for various reasons. These children were re‐examined and a good eye fundus information could be obtained in 105. Moderate and severe regressed ROP was found in 48 and 13 children, respectively. In the Stockholm area the frequency of children with severe ROP (earlier called cicatricial ROP) was 2.5% out of the above risk group of 528. Two children were blind from ROP (0.4%). Ten children had a visual acuity ≤0.3 in the worse eye (1.9%) and 7 of them had ROP changes. Children with a birth weight < 1000 g had the highest frequency of ROP (severe 11.6% and moderate 18.6%) and ocular complications. The results show that preterm born children often present ocular complications, and therefore they need a close follow‐up.
Retinopathy of prematurity in Frederiksborg county 1988–1990
Authors: Fledelius Hans C.
Published: May 2009

Abstract. A report is given of retinopathy of prematurity findings in a Danish county (pop. 342 000) for birth years 1988–90. Out of 12 116 liveborn infants 200 were followed with eye controls during (at least) the first 3 months. In 135 gestational age and/or birth weight were below 32 weeks/1750 g. Twenty‐five had ROP stage 1–2 with uneventful regression. Out of 5 with at least stage 3 ROP 2 had spontaneous regression. Three had cryotherapy; two acquired unilateral blindness, one myopia of prematurity. ‐ As part of an ongoing prospective investigation the visual results denote progress as compared to the serious results from the preceding 6 years (6 blind children). For 1982–90 the pooled ROP blindness rate amounted to 18.7/100 000 liveborn, a frequency only to be surpassed by the neighbouring Copenhagen area. ‐ Considering correct timing of cryotherapy close observation of small premature infants is recommended. At present our screening limits are 32 weeks gestational age/1750 g birth weight.
Eye surgery in severe retinopathy of prematurity
Authors: Fledelius Hans C , Scherfig Erik
Published: May 2009

Abstract. Data concerning observation of 40 pre‐term infants referred to the Copenhagen University eye clinic 1986–91 for evaluation of ROP, predominantly of advanced stages, have been analysed. Twenty‐one eyes in 13 subjects underwent cryotherapy at stage 3 (‐4), on day 50–172 after delivery (median 72 days). Out of 19 eyes available for follow‐up 10 obtained good of fair function; nine eyes ended with no L. Four subjects with ROP stage 4–5 at referral underwent vitrectomy and one trabeculectomy, all in eyes where surgery on beforehand was considered palliative or ‘mainly experimental’. No indication for therapy was recorded in 22 infants; they mainly appeared for evaluation rather late in the course of ROP, to have the feasability of reconstructive anatomy considered. The mean age of the infant at first discovery of ROP was 55 days when only stage 1–2 was found, 63 days when stage 3, and 69 days when at least stage 4 was described. Alltogether, the range was 30–100 days. The inhomogeneity of the data is stressed. Though the possible benefit of earlier recognition cannot be proven, the investigation clearly indicates the need of uniform observation schedules nationwide and clearer indications for referral to the vitreo‐retinal department.
Implications of Limiting CO
2
Concentrations for Land Use and Energy
Authors: Wise Marshall , Calvin Katherine , Thomson Allison , Clarke Leon , Bond-Lamberty Benjamin , Sands Ronald , Smith Steven J. , Janetos Anthony , Edmonds James
Published: May 2009

The Power of Green

Carbon dioxide is produced both by fossil fuel burning and by deforestation and other land-use changes. Limiting both sources of CO
2
is necessary if we are to curb global warming.

Wise
et al.

(p.
1183
) use an integrated assessment model to explore the consequences of limiting atmospheric CO
2
concentrations at levels between 450 and 550 parts per million through a combination of fossil-fuel emissions reductions and land-use modification. Land-use modification strategies reduce the cost of limiting atmospheric CO
2
concentrations, but can make crop prices rise and transform human diets, for example, when people consume less beef and other carbon-intensive protein sources. The rate at which crop productivity is improved has a strong influence on emissions from land-use change. Thus, the technology used for growing crops is potentially as important for limiting atmospheric CO
2
as are approaches like CO
2
capture and storage.
Structural Basis of Transcription: Backtracked RNA Polymerase II at 3.4 Angstrom Resolution
Authors: Wang Dong , Bushnell David A. , Huang Xuhui , Westover Kenneth D. , Levitt Michael , Kornberg Roger D.
Published: May 2009

Stepping Back to Go Forward

Insight into the mechanism of transcription has come from crystal structures of actively transcribing RNA polymerase II complexes in the pre- and posttranslocation states. RNA polymerase also backtracks on the DNA template. Backtracking by only a few residues is reversible, but longer backtracking leads to arrest that is relieved by cleavage of the transcript by the transcription elongation factor SII (TFIIS). Now

Wang
et al.

(p.
1203
) report x-ray structures of backtracked ternary complexes and of a backtracked complex bound to a noncleaving mutant of TFIIS. The structures show a defined one-residue, backtracked state supporting the idea that RNA polymerase oscillates between backward and forward motion during active transcription. Mismatched residues disfavor forward translocation, increasing the lifetime of the backtracked state and facilitating cleavage by TFIIS. Thus, TFIIS-induced cleavage is likely to provide an important proofreading function during transcription.
The Computation of Social Behavior
Authors: Behrens Timothy E. J. , Hunt Laurence T. , Rushworth Matthew F. S.
Published: May 2009

Social Sciences Reviewed

The social sciences focus on multibody problems within changing environments, where the intentions and actions of both actor and acted-upon vary over time. In such situations, it can be challenging, to say the least, to identify unambiguously and persuasively which behaviors are causes, which are effects, and which are epiphenomena.

Behrens
et al.

(p.
1160
) review the recent application of formal behavioral models in the area of social cognitive neuroscience.
Comment on “A Large Excess in Apparent Solar Oblateness Due to Surface Magnetism”
Authors: Kuhn J. R. , Emilio M. , Bush R.
Published: May 2009

Fivian
et al
. (Reports, 24 October 2008, p. 560) analyzed data from the Reuven Ramaty High-Energy Solar Spectroscopic Imager satellite and reported that the Sun is more oblate than previous measurements have suggested. We argue that their threshold-based analysis yields a biased measure of the solar limb shape geometry.
Response to Comment on “A Large Excess in Apparent Solar Oblateness Due to Surface Magnetism”
Authors: Fivian M. D. , Hudson H. S. , Lin R. P. , Zahid H. J.
Published: May 2009

Our analysis of satellite data from the Reuven Ramaty High-Energy Spectroscopic Imager revealed a strong correlation with a magnetic proxy, leading to an anomalous increase of the solar oblateness. We modeled this effect to yield an oblateness measurement of an assumed underlying nonmagnetic Sun. Kuhn
et al
. note that this measurement could be confused with a systematic spatial brightness variation. The existing data on this are ambiguous.
Genome-Wide Identification of Human RNA Editing Sites by Parallel DNA Capturing and Sequencing
Authors: Li Jin Billy , Levanon Erez Y. , Yoon Jung-Ki , Aach John , Xie Bin , LeProust Emily , Zhang Kun , Gao Yuan , Church George M.
Published: May 2009

Editing Expectations

Although genetic information is stored in DNA, and faithfully copied into RNA, the cell can make the odd (and occasionally vitally important) change to the meaning of code during a process known as RNA editing. Thirteen edited genes are known in the nonrepetitive portion of the human genome, but the overall prevalence of RNA editing is unclear.

Li
et al.

(p.
1210
), used an unbiased genome-wide approach to identify 239 sites (in 207 target genes), with stringent criteria for editing. The sites identified included 10 of the 13 known edited genes. Fourteen out of 18 randomly chosen sites were validated by sequencing, and these putatively edited genes were enriched for synapse, cell trafficking, and membrane functions. Furthermore, lowering the search stringency suggested that many more human genes may be edited at lower frequencies.