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Stereotactic radiosurgery (SRS) is a valuable treatment option for uveal melanoma, offering excellent tumour control rates and eye preservation. Its efficacy relies upon accurate localisation of the tumour, which is challenging in the mobile eye. Various methods of globe immobilisation have been used, including non-invasive devices, such as eye movement tracking and suction cups, but common practice is to use local anaesthetic block with or without transconjunctival suturing of the extraocular muscles. Some studies have suggested that the addition of muscle suturing to local anaesthetic block provides better immobilisation of the globe, when compared to anaesthetic block alone. Controversy exists regarding the clinical relevance of this observation and ocular oncologists differ in their choice of immobilisation technique. In order to establish if the addition of muscle suturing to local anaesthetic block improves clinical outcomes, we performed a retrospective review of all cases that underwent SRS for uveal melanoma over a 10-year period (May 2008 to May 2018). Based on surgeon preference, all patients received either local anaesthetic block plus muscle suturing (Group A) or local anaesthetic block alone (Group B) to induce globe akinesia. Outcomes assessed were primary treatment failure, tumour recurrence, secondary enucleation and death rate. In our cohort of 290 eyes; 118 patients were in group A and 172 patients were in group B. There were no cases of primary treatment failure in either group. With a minimum of 24 months follow-up, only 3 patients experienced tumour recurrence (1 in group A and 2 in group B). There was no significant difference in recurrence, enucleation and all-cause death rates between the two groups. Our retrospective review suggests that although extraocular muscle suturing may be considered by some units to provide superior globe immobilisation for SRS, it does not alter the clinical outcome. [ABSTRACT FROM AUTHOR]

In weather forecasting, current and past observational data are routinely assimilated into numerical simulations to produce ensemble forecasts of future events in a process termed “model steering”. Here we describe a similar approach that is motivated by analyses of previous forecasts of the Working Group on California Earthquake Probabilities (WGCEP). Our approach is adapted to the problem of earthquake forecasting using topologically realistic numerical simulations for the strike-slip fault system in California. By systematically comparing simulation data to observed paleoseismic data, a series of spatial probability density functions (PDFs) can be computed that describe the probable locations of future large earthquakes. We develop this approach and show examples of PDFs associated with magnitude M > 6.5 and M > 7.0 earthquakes in California.

Aims To investigate the success and recurrence rates and visual outcomes in a large case series of amelanotic posterior choroidal melanomas treated by means of primary photodynamic therapy (PDT) with verteporfin. Methods Retrospective case series from a single specialist ocular oncology centre. All patients had a clinical diagnosis of choroidal melanoma and were selected for PDT based on tumour characteristics. Included patients had at least 24 months of follow-up from initiation of treatment and all but one had not received treatment prior to PDT. Results 69 patients were included. Mean tumour thickness was 1.9 mm (range 0.5-4.4), while the mean basal diameter was 6.9 mm (range 2.4-11.0). Included lesions were stage cT1a (n=66) or cT2a (n=3). The mean duration of follow-up from treatment initiation was 57 months (range 24-116 months). Seven lesions (10%) failed to respond to PDT. 10 patients (16%) experienced recurrence during follow-up. Overall success rate in this series was 75% (n=52). 83% of successfully treated patients (n=43) maintained or gained vision by final follow-up. Visual outcomes were significantly better in those patients who received PDT therapy alone in comparison to those who needed other treatments for their melanoma (Fisher's exact test, p=0.004). Unfortunately, one patient (1.4%) in the series developed systemic metastases and died. Conclusion Selected amelanotic posterior uveal melanomas may be successfully treated with PDT with retention of good vision in the majority of cases, maintained with a mean of 57 months (minimum of 24 months) of follow-up. [ABSTRACT FROM AUTHOR]

Photodynamic therapy is well-established as a treatment for a number of conditions in ophthalmology, principally in the field of medical retina, but less so in ocular oncology. Cancer of the eye is rare, the commonest lesions to affect the globe being choroidal melanoma (as a primary malignancy) and choroidal metastases (a secondary malignancy). The mainstay of treatment of such lesions remains radiotherapy in various forms, however, photodynamic therapy does have a useful role to play in the management of such patients. In this article, I hope to review the current indications, treatment regimes, and the risks and benefits of photodynamic therapy (PDT) as a treatment for eye cancer. [ABSTRACT FROM AUTHOR]

The Virtual California simulation tool can be used to study fault and stress interaction scenarios for realistic California earthquakes and produces a large data set, which is ideally suited for statistical analysis. As with any complex system, it can produce emergent phenomena unexpected by its designers; these can be studied in order to gain insight into real world geophysical phenomena. We have developed a statistical method to analyze Virtual California data that enables us to determine the correlation relationships between the simulated fault elements. We present the results of this analysis of 40 000 years of data for 59 faults (639 elements). We focus on five specific cases that display noteworthy behavior that includes long-range fault interactions, activation–quiescence, and complex small-scale interactions. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Earthquakes on a specified fault (or fault segment) with magnitudes greater than a specified value have a statistical distribution of recurrence times. The mean recurrence time can be related to the rate of strain accumulation and the strength of the fault. Very few faults have a recorded history of earthquakes that define a distribution well. For hazard assessment, in general, a statistical distribution of recurrence times is assumed along with parameter values. Assumed distributions include the Weibull (stretched exponential) distribution, the lognormal distribution, and the Brownian passage-time (inverse Gaussian) distribution. The distribution of earthquake waiting times is the conditional probability that an earthquake will occur at a time in the future if it has not occurred for a specified time in the past. The distribution of waiting times is very sensitive to the distribution of recurrence times. An exponential distribution of recurrence times is Poissonian, so there is no memory of the last event. The distribution of recurrence times must be thinner than the exponential if the mean waiting time is to decrease as the time since the last earthquake increases. Neither the lognormal or the Brownian passage time distribution satisfies this requirement. We use the "Virtual California" model for earthquake occurrence on the San Andreas fault system to produce a synthetic distribution of earthquake recurrence times on various faults in the San Andreas system. We find that the synthetic data are well represented by Weibull distributions. We also show that the Weibull distribution follows from both damage mechanics and statistical physics. [ABSTRACT FROM AUTHOR]

The article provides a historical perspective on photodynamic therapy (PDT) as well as an overview of its current uses in ocular oncology. PDT has become well known to ophthalmologists, principally as a treatment for exudative age-related macular degeneration. Whilst this remains the most frequent use of PDT in ophthalmology, it is also used in a variety of conditions in the fields of both ocular oncology and medical retina.

Provides a global real-time accessibility to a diverse set of earthquake and fault database. Development of an understanding of active tectonic and earthquake processes; Provision of global access to geologic reference models of faults and fault data; Details on the effective use of large data sets in the solid earth sciences.

Retinal vascular tumors can be classified into four distinct clinical entities, which include retinal capillary hemangioma, retinal cavernous hemangioma, retinal arteriovenous communications (Wyburn-Mason syndrome), and retinal vasoproliferative tumor.