Multi-luminance mobility testing after gene therapy in the context of retinal functional diagnostics

BACKGROUND

Voretigene neparvovec (Luxturna®) is the first approved gene therapy for RPE65-linked Leber congenital amaurosis (LCA). Though individual effects are highly variable, most recipients report improved vision in everyday life. To describe such effects, visual navigation tests are now frequently used in clinical trials. However, it is still unclear how their results should be interpreted compared to conventional parameters of visual function.

METHODS

Seven LCA patients underwent a multi-luminance visual navigation test (Ora-VNCTM) before and 3 months after receiving Luxturna gene therapy. Their performance was rated based on the luminance level at which they passed the course. Differences between the first and second test were correlated to changes in visual acuity, full-field stimulus thresholds, chromatic pupil campimetry, and dark-adapted perimetry.

RESULTS

A few patients displayed notable improvements in conventional measures of visual function whereas patients with advanced retinal degeneration showed no relevant changes. Independent of these results, almost all participants improved in the visual navigation task by one or more levels. The improvement in the mobility test was best correlated to the change in full-field stimulus thresholds. Other measures of visual functions showed no clear correlation with visual navigation.

DISCUSSION

In patients who passed the test's more difficult levels, improved visual navigation can be attributed to the reactivation of rods. However, the performance of patients with low vision seemed to depend much more on confounding factors in the easier levels. In sum, such tests might only be meaningful for patients with better preserved visual functions.

Short term morphological rescue of the fovea after gene therapy with voretigene neparvovec

PURPOSE

Leber congenital amaurosis type 2 (LCA2) and early-onset severe retinal dystrophy (EOSRD) are linked to visual impairment with nyctalopia and visual acuity reduction in early childhood. In 2017, the first gene therapy voretigene neparvovec (Luxturna™) for patients with LCA and EOSRD cause by bi-allelic mutations in the RPE65 gene has been approved. Here we report on an example of short-term change in the foveal morphology after functionally successful gene therapy with voretigene neparvovec in a 15-year old patient.

METHODS

The clinical examinations included best corrected visual acuity (BCVA), spectral domain optical coherence tomography (OCT) and adaptive optics retinal imaging.

RESULTS

During follow-up over a period of 3 months after the treatment, an improvement of the central foveal morphology could be observed in OCT, with a clear demarcation of the external limiting membrane and changes in the photoreceptor mosaic on adaptive optics retinal imaging. These morphological rescue parameters correlated in part with the improvement in foveal-mediated vision after the treatment and adaptive optics imaging. Although the visual acuity improved only slightly at month 3, objective central cone evaluation with chromatic pupil campimetry showed an increase in the central sensitivity. In daily life, the patient reported her visional experience after the treatment as 'brighter'.

CONCLUSION

Rapid changes in the correlates of photoreceptor morphology after successful gene therapy in patients with LCA/EORD can be quantifiable on individual level.

[Interventional pain therapy. Results of a survey among specialized pain physicians in Germany]

BACKGROUND

Interventional pain therapy aims to treat pain which is refractory to pharmacologic and noninterventional treatment. Due to the partly lacking evidence and recommendations it remains unclear when interventional methods should be applied within the treatment pathway. This study assesses the current state of interventional methods in Germany and their leading indications comparing with the recommendations found in the literature.

METHODS

An online survey was conducted among German physicians specialized in pain therapy concerning the number of interventions they perform per quarter, which supporting measures they use, and their indications for sympathetic blocks, sensory blocks, intrathecal administration, and spinal cord stimulation.

RESULTS

A total of 109 physicians (23.5 %) participated in the survey. Blocks are most often performed on the stellate ganglion (94 %) and on the superior cervical ganglion (82 %). They are supported by anatomical landmarks and less often by imaging control. Both classic neuropathic pain diagnoses (e.g., complex regional pain syndrome) and diagnoses with a neuropathic pain component (e.g., peripheral arterial disease, tumor pain, and back pain) were considered as indications to perform interventional procedures.

CONCLUSION

Although there is no clear evidence on interventional procedures in the current literature, these methods are often performed by the respondents. Anatomic landmarks are most frequently used for orientation. The German pain physicians who responded consider especially neuropathic pain as an indication to perform interventional procedures for pain therapy.