Sussex Eye Hospital

The Westerbork Northern Sky Survey (WENSS) is a low-frequency radio survey that will cover the whole sky north of at a wavelength of 92 cm to a limiting flux density of approximately 18 mJy (). This survey has a resolution of and a positional accuracy for strong sources of . Here we present a source list comprising 11 299 sources and maps of 120 extended sources for a 570 square degree region around the north ecliptic pole, the so-called mini-survey. We discuss the errors and reliability of the source parameters and the completeness of the survey.

BACKGROUND: Permanent pacemaker (PPM) requirement is a recognized complication of transcatheter aortic valve implantation. We assessed the UK incidence of permanent pacing within 30 days of CoreValve implantation and formulated an anatomic and electrophysiological model. METHODS AND RESULTS: Data from 270 patients at 10 centers in the United Kingdom were examined. Twenty-five patients (8%) had preexisting PPMs; 2 patients had incomplete data. The remaining 243 were 81.3±6.7 years of age; 50.6% were male. QRS duration increased from 105±23 to 135±29 milliseconds (P<0.01). Left bundle-branch block incidence was 13% at baseline and 61% after the procedure (P<0.001). Eighty-one patients (33.3%) required a PPM within 30 days. Rates of pacing according to preexisting ECG abnormalities were as follows: right bundle-branch block, 65.2%; left bundle-branch block, 43.75%; normal QRS, 27.6%. Among patients who required PPM implantation, the median time to insertion was 4.0 days (interquartile range, 2.0 to 7.75 days). Multivariable analysis revealed that periprocedural atrioventricular block (odds ratio, 6.29; 95% confidence interval, 3.55 to 11.15), balloon predilatation (odds ratio, 2.68; 95% confidence interval, 2.00 to 3.47), use of the larger (29 mm) CoreValve prosthesis (odds ratio, 2.50; 95% confidence interval, 1.22 to 5.11), interventricular septum diameter (odds ratio, 1.18; 95% confidence interval, 1.10 to 3.06), and prolonged QRS duration (odds ratio, 3.45; 95% confidence interval, 1.61 to 7.40) were independently associated with the need for PPM. CONCLUSION: One third of patients undergoing a CoreValve transcatheter aortic valve implantation procedure require a PPM within 30 days. Periprocedural atrioventricular block, balloon predilatation, use of the larger CoreValve prosthesis, increased interventricular septum diameter and prolonged QRS duration were associated with the need for PPM.

Also note that G308.7+0.0 has been renamed G308.8-0.1 because of improved observations revealing its extent more

We present an extension of the Kompaneets equation which allows relativistic effects to be included to any desired order. Using this, we are able to obtain simple analytic forms for the spectral changes due to the Sunyaev-Zel'dovich effect in hot clusters, correct to first and second order in the expansion parameter theta_e=k_B T_e/m c^2. These analytic forms agree with previous numerical calculations of the effect based upon the multiple scattering spectrum for k_B T_e up to 10 keV. Our results confirm previous conclusions that the result of including relativistic corrections in the Sunyaev-Zel'dovich effect is a small reduction in the amplitude of the effect over the majority of the spectrum: specifically we find Delta T/T = -2y(1 - 17/10 theta_e + 123/40 theta_e^2) (correct to second-order) in the Rayleigh-Jeans region, where y is the usual Comptonization parameter. For a typical cluster temperature of 8 keV, this amounts to a correction downwards to the value of the Hubble constant derived using combined X-ray and Rayleigh-Jeans Sunyaev-Zel'dovich information by about 5 percent.

The osteo-odonto-keratoprosthesis (OOKP), although described over 40 years ago, remains the keratoprosthesis of choice for end-stage corneal blindness not amenable to penetrating keratoplasty. It is particularly resilient to a hostile environment such as the dry keratinized eye resulting from severe Stevens-Johnson syndrome, ocular cicatricial pemphigoid, trachoma, and chemical injury. Its rigid optical cylinder gives excellent image resolution and quality. The desirable properties of the theoretical ideal keratoprosthesis is described. The indications, contraindications, and patient assessment (eye, tooth, buccal mucosa, psychology) for OOKP surgery are described. The surgical and anaesthetic techniques are described. Follow-up is life-long in order to detect and treat complications, which include oral, oculoplastic, glaucoma, vitreo-retinal complications and extrusion of the device. Resorption of the osteo-odonto-lamina is responsible for extrusion, and this is more pronounced in tooth allografts. Regular imaging with spiral-CT or electron beam tomography can help detect bone and dentine loss. The optical cylinder design is discussed. Preliminary work towards the development of a synthetic OOKP analogue is described. Finally, we describe how to set up an OOKP national referral center.

GRB 000926 has one of the best-studied afterglows to-date, with multiple X-ray observations, as well as extensive multi-frequency optical and radio coverage. Broadband afterglow observations, spanning from X-ray to radio frequencies, provide a probe of the density structure of the circumburst medium, as well as of the ejecta energetics, geometry, and the physical parameters of the relativistic blastwave resulting from the explosion. We present an analysis of Chandra X-ray Observatory observations of this event, along with Hubble Space Telescope and radio monitoring. We combine these data with ground-based optical and IR observations and fit the synthesized afterglow lightcurve using models where collimated ejecta expand into a surrounding medium. We find that we can explain the broadband lightcurve with reasonable physical parameters if the cooling is dominated by inverse Compton scattering. For this model, an excess due to inverse Compton scattering appears above the best-fit synchrotron spectrum in the X-ray band. No previous bursts have exhibited this component, and its observation would imply that the GRB exploded in a moderately dense (n ∼ 30 cm −3) medium, consistent with a diffuse interstellar cloud environment. 1.

PurposeTo test whether reducing radiation dose to uninvolved bladder while maintaining dose to the tumor would reduce side effects without impairing local control in the treatment of muscle-invasive bladder cancer.Methods and MaterialsIn this phase III multicenter trial, 219 patients were randomized to standard whole-bladder radiation therapy (sRT) or reduced high-dose volume radiation therapy (RHDVRT) that aimed to deliver full radiation dose to the tumor and 80% of maximum dose to the uninvolved bladder. Participants were also randomly assigned to receive radiation therapy alone or radiation therapy plus chemotherapy in a partial 2 × 2 factorial design. The primary endpoints for the radiation therapy volume comparison were late toxicity and time to locoregional recurrence (with a noninferiority margin of 10% at 2 years).ResultsOverall incidence of late toxicity was less than predicted, with a cumulative 2-year Radiation Therapy Oncology Group grade 3/4 toxicity rate of 13% (95% confidence interval 8%, 20%) and no statistically significant differences between groups. The difference in 2-year locoregional recurrence free rate (RHDVRT − sRT) was 6.4% (95% confidence interval −7.3%, 16.8%) under an intention to treat analysis and 2.6% (−12.8%, 14.6%) in the “per-protocol” population.ConclusionsIn this study RHDVRT did not result in a statistically significant reduction in late side effects compared with sRT, and noninferiority of locoregional control could not be concluded formally. However, overall low rates of clinically significant toxicity combined with low rates of invasive bladder cancer relapse confirm that (chemo)radiation therapy is a valid option for the treatment of muscle-invasive bladder cancer. To test whether reducing radiation dose to uninvolved bladder while maintaining dose to the tumor would reduce side effects without impairing local control in the treatment of muscle-invasive bladder cancer. In this phase III multicenter trial, 219 patients were randomized to standard whole-bladder radiation therapy (sRT) or reduced high-dose volume radiation therapy (RHDVRT) that aimed to deliver full radiation dose to the tumor and 80% of maximum dose to the uninvolved bladder. Participants were also randomly assigned to receive radiation therapy alone or radiation therapy plus chemotherapy in a partial 2 × 2 factorial design. The primary endpoints for the radiation therapy volume comparison were late toxicity and time to locoregional recurrence (with a noninferiority margin of 10% at 2 years). Overall incidence of late toxicity was less than predicted, with a cumulative 2-year Radiation Therapy Oncology Group grade 3/4 toxicity rate of 13% (95% confidence interval 8%, 20%) and no statistically significant differences between groups. The difference in 2-year locoregional recurrence free rate (RHDVRT − sRT) was 6.4% (95% confidence interval −7.3%, 16.8%) under an intention to treat analysis and 2.6% (−12.8%, 14.6%) in the “per-protocol” population. In this study RHDVRT did not result in a statistically significant reduction in late side effects compared with sRT, and noninferiority of locoregional control could not be concluded formally. However, overall low rates of clinically significant toxicity combined with low rates of invasive bladder cancer relapse confirm that (chemo)radiation therapy is a valid option for the treatment of muscle-invasive bladder cancer.

Continuing the observational campaign initiated by our group, we present the long term spectral evolution of the Galactic black hole candidate Cygnus X-1 in the X-rays and at 15 GHz. We present ~200 pointed observations taken between early 1999 and late 2004 with the Rossi X-ray Timing Explorer and the Ryle radio telescope. The X-ray spectra are remarkably well described by a simple broken power law spectrum with an exponential cutoff. Physically motivated Comptonization models, e.g., by Titarchuk (1994, ApJ, 434, 570, compTT) and by Coppi (1999, in High Energy Processes in Accreting Black Holes, ed. J. Poutanen, & R. Svensson (San Francisco: ASP), ASP Conf. Ser., 161, 375, eqpair), can reproduce this simplicity; however, the success of the phenomenological broken power law models cautions against “overparameterizing” the more physical models. Broken power law models reveal a significant linear correlation between the photon index of the lower energy power law and the hardening of the power law at ~10 keV. This phenomenological soft/hard power law correlation is partly attributable to correlations of broad band continuum components, rather than being dominated by the weak hardness/reflection fraction correlation present in the Comptonization model. Specifically, the Comptonization models show that the bolometric flux of a soft excess (e.g., disk component) is strongly correlated with the compactness ratio of the Comptonizing medium, with . Over the course of our campaign, Cyg X-1 transited several times into the soft state, and exhibited a large number of “failed state transitions”. The fraction of the time spent in such low radio emission/soft X-ray spectral states has increased from ~10% in 1996–2000 to ~34% since early 2000. We find that radio flares typically occur during state transitions and failed state transitions (at ), and that there is a strong correlation between the 10–50 keV X-ray flux and the radio luminosity of the source. We demonstrate that rather than there being distinctly separated states, in contrast to the timing properties the spectrum of Cyg X-1 shows variations between extremes of properties, with clear cut examples of spectra at every intermediate point in the observed spectral correlations.

BACKGROUND: Fuchs endothelial dystrophy (FED) is a condition in which there is premature degeneration of corneal endothelial cells. When the number of endothelial cells is reduced to a significant degree, fluid begins to accumulate within the cornea. As a result, the cornea loses its transparency and the individual suffers a reduction in vision. The only successful surgical treatment for this condition is replacement of part or all of the cornea with healthy tissue from a donor. The established procedure, penetrating keratoplasty (PKP), has been used for many years and its safety and efficacy are well known. Endothelial keratoplasty (EK) techniques are relatively new surgical procedures and their safety and efficacy relative to PKP are uncertain. OBJECTIVES: The objective of this review was to compare the benefits and complications related to two surgical methods (EK and PKP) of replacing the diseased endothelial layer of the cornea with a healthy layer in people with FED. SEARCH METHODS: We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2014, Issue 1), MEDLINE (January 1950 to January 2014), EMBASE (January 1980 to January 2014), Latin American and Caribbean Health Sciences Literature Database (LILACS) (January 1982 to January 2014), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com) and ClinicalTrials.gov (www.clinicaltrials.gov). There were no date or language restrictions in the electronic searches for trials. The electronic databases were last searched on 27 January 2014. SELECTION CRITERIA: We included all randomised controlled trials (RCTs) comparing EK versus PKP for people (of any age and gender) who had been clinically diagnosed with FED. DATA COLLECTION AND ANALYSIS: Two authors independently screened the search results, assessed trial quality and extracted data using the standard methodological procedures expected by The Cochrane Collaboration. MAIN RESULTS: We included three RCTs that enrolled a total of 139 eyes of 136 participants and analysed 123 (88%) eyes. Two RCTs randomised eyes into either the endothelial keratoplasty (EK) group or penetrating keratoplasty (PKP) group and one RCT randomised eyes into either the femtosecond laser-assisted endothelial keratoplasty (FLEK) group or PKP group. The RCTs comparing EK with PKP did not show any significant differences between procedures with respect to best corrected visual acuity (BCVA) at two years (mean difference (MD) 0.14 logMAR; 95% confidence interval (CI) -0.08 to 0.36; P = 0.23) or at one year (MD 0.09 logMAR; 95% CI -0.05 to 0.23; P = 0.22), whereas the trial comparing FLEK with PKP showed significantly better BCVA after PKP (MD 0.20 logMAR; 95% CI 0.10 to 0.30; P = 0.0001). Only one RCT reported on irregular astigmatism (higher-order aberration), which was less with EK than PKP (MD -1.20 µm; 95% CI -1.53 to -0.87; P < 0.001). Only one RCT reported on endothelial cell counts (lower after FLEK than PKP: MD -969 cells/mm²; 95% CI -1161 to -777; P < 0.001), primary graft failure (higher after FLEK than PKP: RR 7.76; 95% CI 0.41 to 145.22; P = 0.10), and graft rejection (more after FLEK than PKP: RR 1.11; 95% CI 0.07 to 17.12; P = 0.94). Only one RCT reported that 27.8% of participants had graft dislocation, 2.8% had epithelial ingrowth and postoperative pupillary block, and 13.9% had intraocular pressure (IOP)-related problems in the FLEK group compared with the PKP group, in whom 10% had suture-related problems, 5% had wound dehiscence and 10% had suture revision to correct astigmatism. Overall, the adverse events in the FLEK group appeared to be more frequent than in the PKP group. No trials reported information about quality of life or economic data. The overall methodological quality of the three trials was not satisfactory as most did not perform allocation concealment or masking of participants and outcome assessors, and all trials had a small sample size. AUTHORS' CONCLUSIONS: The rapid growth of endothelial keratoplasty as the treatment of choice for FED is based upon the belief that visual recovery is more rapid, surgically induced astigmatism (regular and irregular) is less and rates of transplant rejection are lower with EK. This change in practice also assumes that the rates of long term transplant survival are equal for the two procedures. The practical differences between the surgical procedures mean that visual recovery is inherently more rapid following EK, but this review found no strong evidence from RCTs of any difference in the final visual outcome between EK and PKP for people with FED. This review also found that higher order aberrations are fewer following EK but endothelial cell loss is greater following EK. The RCTs that we included employed different EK techniques, which may have a bearing on these findings. EK procedures have evolved over the years and can be performed using different techniques, for example deep lamellar endothelial keratoplasty, Descemets stripping endothelial keratoplasty (DSEK), Descemets stripping automated endothelial keratoplasty (DSAEK), femtosecond laser-assisted endothelial keratoplasty and Descemet membrane endothelial keratoplasty (DMEK). More RCTs are needed to compare PKP with commonly performed EK procedures such as DSEK, DSAEK and DMEK in order to determine the answers to two key questions, whether there is any difference in the final visual outcome between these techniques and whether there are differences in the rates of graft survival in the long term?

We present an extension of the Kompaneets equation which allows relativistic effects to be included to any desired order. Using this, we are able to obtain simple analytic forms for the spectral changes due to the Sunyaev-Zel'dovich effect in hot clusters, correct to first and second order in the expansion parameter theta_e=k_B T_e/m c^2. These analytic forms agree with previous numerical calculations of the effect based upon the multiple scattering spectrum for k_B T_e up to 10 keV. Our results confirm previous conclusions that the result of including relativistic corrections in the Sunyaev-Zel'dovich effect is a small reduction in the amplitude of the effect over the majority of the spectrum: specifically we find Delta T/T = -2y(1 - 17/10 theta_e + 123/40 theta_e^2) (correct to second-order) in the Rayleigh-Jeans region, where y is the usual Comptonization parameter. For a typical cluster temperature of 8 keV, this amounts to a correction downwards to the value of the Hubble constant derived using combined X-ray and Rayleigh-Jeans Sunyaev-Zel'dovich information by about 5 percent.

PURPOSE: To establish a time-proven "gold standard" in modified osteoodontokeratoprosthesis (OOKP) surgery. METHODS: The OOKP is the procedure of choice for restoring sight in patients with corneal blindness caused by end-stage ocular surface disease not amenable to penetrating keratoplasty. Members of the OOKP Study Group met in Rome, Italy in 2001 and Vienna, Austria in 2002 to discuss indications and contraindications, patient selection, surgical technique, postoperative care, and recognition and management of complications of OOKP surgery according to Strampelli and modified by Falcinelli. RESULTS: Falcinelli's modification of Strampelli's technique of OOKP surgery remains the gold standard as far as visual and keratoprosthesis-retention results are concerned. The agreement on indications and contraindications, patient selection, surgical technique, postoperative care, and recognition and management of complications of this technique of OOKP surgery is summarized in the text of this manuscript. CONCLUSION: This standard technique of modified OOKP surgery, where adequately performed, is capable of providing excellent anatomic and functional results even in the long term. In patients with corneal blindness untreatable by other approaches, we strongly recommend this technique for visual rehabilitation. Students of OOKP surgery should become familiar with the protocol described in this paper before subjecting the technique to further modifications.

The X-ray nova XTE J1118+480 suffers minimal extinction (b = 62 degrees) and therefore represents an outstanding opportunity for multiwavelength studies. Hynes et al. (2000) conducted the first such study, which was centered on 2000 April 8 using UKIRT, EUVE, HST and RXTE. On 2000 April 18, the Chandra X-ray Observatory obtained data coincident with a second set of observations using all of these same observatories. A 30 ks grating observation using Chandra yielded a spectrum with high resolution and sensitivity covering the range 0.24-7 keV. Our near-simultaneous observations cover approximately 80% of the electromagnetic spectrum from the infrared to hard X-rays. The UV/X-ray spectrum of XTE J1118+480 consists of two principal components. The first of these is an approximately 24 eV thermal component which is due to an accretion disk with a large inner disk radius: > 35 Schwarzschild radii. The second is a quasi power-law component that was recorded with complete spectral coverage from 0.4-160 keV. A model for this two-component spectrum is presented in a companion paper by Esin et al. (2001).

Fluctuations in the cosmic microwave background (CMB) temperature are being studied with ever increasing precision. Two competing types of theories might describe the origins of these fluctuations: ``inflation'' and ``defects.'' Here we show how the differences between these two scenarios can give rise to striking signatures in the microwave fluctuations on small scales, assuming a standard recombination history. These should enable high resolution measurements of CMB anisotropies to distinguish between these two broad classes of theories, independent of the precise details of each.

PURPOSE: To review and compare the published reports of Descemet membrane endothelial keratoplasty (DMEK) and Descemet stripping endothelial keratoplasty/Descemet stripping automated endothelial keratoplasty (DSEK/DSAEK) procedures with regard to endothelial cell density/loss, best spectacle-corrected visual acuity, central corneal thickness, subjective outcomes (patient's reported satisfaction/preference), and postoperative complications. METHODS: A thorough search was conducted in the databases including AMED, EMBASE, Cochrane Database of Systematic Reviews, and MEDLINE without date restrictions. Systematic reviews, meta-analysis, randomized controlled trials, case series, and audits comparing DMEK and DSAEK were included. RESULTS: DMEK is superior to DSAEK for the following outcomes: visual acuity, central corneal thickness, and patient satisfaction. There was a statistically significant difference in the mean spectacle-corrected visual acuity at 6 months for DMEK (mean = 0.161, SD = 0.129) and DSAEK eye (mean = 0.293, SD = 0.153) conditions; t (297) = 8.042, P < 0.0001. The pooled mean difference was -0.13 (95% confidence interval, -0.16 to -0.09) and I = 44%, indicating better visual acuity for DMEK. Mean postoperative endothelial cell density showed statistically no significant difference in the mean values for DMEK (mean = 1855, SD = 442) and DSAEK eye (mean = 1872, SD = 429) conditions; t (336) = 0.375, P = 0.708. A higher proportion of patients prefer DMEK to DSAEK. However, DSAEK is superior to DMEK with respect to the need for rebubbling as the rebubbling rate was higher in the DMEK group. CONCLUSIONS: Although DMEK is associated with a higher rate of rebubbling, better visual outcomes were seen in DMEK.

Tilt and decentration of intraocular lenses (IOL) may occur secondary to a complicated cataract surgery or following an uneventful phacoemulsification. Although up to 2-3° tilt and a 0.2-0.3 mm decentration are common and clinically unnoticed for any design of IOL, larger extent of tilt and decentration has a negative impact on the optical performance and subsequently, the patients' satisfaction. This negative impact does not affect various types of IOLs equally. In this paper we review the methods of measuring IOL tilt and decentration and focus on the effect of IOL tilt and decentration on visual function, in particular visual acuity, dysphotopsia, and wavefront aberrations. Our review found that the methods to measure the IOL displacement have significantly evolved and the available studies have employed different methods in their measurement, while comparability of these methods is questionable. There has been no universal reference point and axis to measure the IOL displacement between different studies. A remarkably high variety and brands of IOLs are used in various studies and occasionally, opposite results are noticed when two different brands of a same design were compared against another IOL design in two studies. We conclude that <5° of inferotemporal tilt is common in both crystalline lenses and IOLs with a correlation between pre- and postoperative lens tilt. IOL tilt has been noticed more frequently with scleral fixated compared with in-the-bag IOLs. IOL decentration has a greater impact than tilt on reduction of visual acuity. There was no correlation between IOL tilt and decentration and dysphotopsia. The advantages of aspheric IOLs are lost when decentration is >0.5 mm. The effect of IOL displacement on visual function is more pronounced in aberration correcting IOLs compared to spherical and standard non-aberration correcting aspherical IOLs and in multifocal versus monofocal IOLs. Internal coma has been frequently associated with IOL tilt and decentration, and this increases with pupil size. There is no correlation between spherical aberration and IOL tilt or decentration. Although IOL tilt produces significant impact on visual outcome in toric IOLs, these lenses are more sensitive to rotation compared to tilt.

The search for a substitute for the natural cornea dates back more than 200 years. Although several devices have been developed and trialled, very few have had successful long-term results and continue in regular clinical use. Keratoprosthesis (KPro) surgery is complex and should be performed in centres with an experienced multidisciplinary team. Currently available KPro devices range from the totally synthetic, such as the Boston KPro, to the totally biological tissue-engineered artificial cornea. The osteo-odonto keratoprothesis combines a synthetic optic with a biological haptic. All keratoprostheses have significant limitations, although visual improvement is possible with each of the devices in clinical use today. This review discusses these devices with emphasis on their indications, surgical techniques and results, before briefly exploring emerging devices and innovative approaches for the future.

We have carried out a survey of optically selected dark clouds using the bolometer array SCUBA on the James Clerk Maxwell Telescope at λ = 850 μm. The survey covers a total of 0.5 deg2 and is unbiased with reference to cloud size, star formation activity, and the presence of infrared emission. Several new protostars and starless cores have been discovered; the protostars are confirmed through the detection of their accompanying outflows in CO (2–1) emission. The survey is believed to be complete for Class 0 and Class I protostars, and yields two important results regarding the lifetimes of these phases. First, the ratio of Class 0 to Class I protostars in the sample is roughly unity, very different from the 1 : 10 ratio that has previously been observed for the ρ Ophiuchi star-forming region. Assuming star formation to be a homogeneous process in the dark clouds, this implies that the Class 0 lifetime is similar to the Class I phase, which from infrared surveys has been established to be ∼2 × 105 yr. It also suggests there is no rapid initial accretion phase in Class 0 objects. A burst of triggered star formation some ∼105 yr ago can explain the earlier results for ρ Ophiuchus. Second, the number of starless cores is approximately twice that of the total number of protostars, indicating a starless core lifetime of ∼8 × 105 yr. These starless cores are therefore very short lived, surviving only two or three free-fall times. This result suggests that, on size scales of ∼104 AU at least, the dynamical evolution of starless cores is probably not controlled by magnetic processes.

The recent discovery of dust-correlated diffuse microwave emission has prompted two rival explanations: free-free emission and spinning dust grains. We present new detections of this component at 10 and 15 GHz by the switched-beam Tenerife experiment. The data show a turnover in the spectrum and thereby support the spinning dust hypothesis. We also present a significant detection of synchrotron radiation at 10 GHz, which is useful for normalizing foreground contamination of cosmic microwave background experiments at high galactic latitudes.

AIMS: To report the long-term results of osteo-odonto-keratoprosthesis (OOKP) surgery in the visual rehabilitation of patients with corneal blindness from end-stage inflammatory ocular surface disease. METHODS: A non-comparative retrospective case series of 36 consecutive patients treated at the National OOKP referral centre in Brighton, UK, between November 1996 and March 2006. RESULTS: A total of 36 patients, with age ranging from 19 to 87 years (mean 51 (SD 19) years), were included in the analysis. The main preoperative diagnoses were Stevens-Johnson syndrome (n = 16, or 44%), severe thermal or chemical burns (n = 6, or 17%), and mucous membrane pemphigoid (n = 5, or 14%). The remainder of the cases comprised miscellaneous causes of dry eye (n = 9, or 25%), which included one each of graft versus host disease, ectodermal dysplasia, ionising radiation damage, cicatrising conjunctivitis from topical medication, trachoma, congenital trigeminal nerve hypoplasia, linear IgA disease, Sjögren syndrome and nutritional deficiency. Follow-up ranged from 6 months to 9 years (mean 3.9 (SD 2.5) years). Anatomical retention during the entirety of the follow-up period was seen in 72% of patients. The main factor resulting in anatomical failure was resorption of the OOKP lamina, which occurred in seven cases (or 19%). Predicted resorption in three cases resulted in successful planned exchange of the lamina, but two cases underwent emergency removal of the OOKP, and two cases developed endophthalmitis. Human leucocyte antigen-matched allografts suffered a higher rate of laminar resorption. Out of the entire cohort, 30 patients (or 83%) had some improvement in vision, 28 (or 78%) achieved vision of 6/60 or better, and 19 (or 53%) achieved 6/12 or better. The best-achieved vision was retained throughout the follow-up period in 61% of cases. Survival analysis suggested that the probability of retaining vision >6/60 5 years after surgery was 53 (10)%. Vision-threatening complications occurred in nine cases (or 25%) and included endophthalmitis, retinal detachment and glaucoma. De novo glaucoma occurred in six patients (or 24%) but was seen overall in 17 patients (or 47%), 10 of whom required surgical treatment. CONCLUSION: OOKP surgery can restore useful and lasting vision in patients suffering from end-stage ocular surface disease, for whom conventional corneal surgery is not possible. The main problems seen in this study were laminar resorption, particularly in allografts, and glaucoma.

We present broad-band radio observations of the afterglow of GRB000301C, spanning from 1.4 to 350 GHz for the period of 3 to 83 days after the burst. This radio data, in addition to measurements at the optical bands, suggest that the afterglow arises from a collimated outflow, i.e. a jet. To test this hypothesis in a self-consistent manner, we employ a global fit and find that a model of a jet, expanding into a constant density medium (ISM+jet), provides the best fit to the data. A model of the burst occurring in a wind-shaped circumburst medium (wind-only model) can be ruled out, and a wind+jet model provides a much poorer fit of the optical/IR data than the ISM+jet model. In addition, we present the first clear indication that the reported fluctuations in the optical/IR are achromatic with similar amplitudes in all bands, and possibly extend into the radio regime. Using the parameters derived from the global fit, in particular a jet break time, t_{jet}=7.5 days, we infer a jet opening angle of \\theta=0.2, and consequently the estimate of the emitted energy in the GRB itself is reduced by a factor of 50 relative to the isotropic value, giving E=1.1 \\times 10^{51} ergs.