Medical hypothesis discovery and innovation in ophthalmology

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Purpose: To determine the effect of upper eyelid platinum chain implantation, with the pretarsal fixation technique, on corneal astigmatism.
Methods: This is a prospective, cohort study. Fifteen eyes of 15 patients underwent upper eyelid platinum chain implantation, with the pretarsal fixation technique, for facial nerve palsy. Information recorded included patient demographics, etiology for facial palsy, weight of the implant, time from onset of paresis to upper eyelid platinum chain implantation, associated surgical procedures, and preoperative and postoperative corneal topography measurements.
Results: Of the 15 patients studied, 10 were male and five were female. The mean age was 55.9 ± 13.8 years (range, 33–87 years). The most common etiology for facial palsy was acoustic neuroma. The weight of the implant ranged from 0.6 to 1.6gr (median 1.2gr). The time from onset of paresis to upper eyelid platinum chain implantation varied from 1 week to 3 months (median 1 month). Four patients had an associated procedure to correct the effect of paralytic ectropion. There was no statistically significant difference in with the rule astigmatism before and after platinum chain implantation.
Conclusions: Upper eyelid platinum chain implantation, with the pretarsal fixation technique, does not appear to cause significant change in corneal astigmatism. This is contrary to data for pretarsal gold weight implantation, which does induce significant with the rule astigmatism.

A 75-year-old woman presented with six months history of progressing lagophthalmos and immobility of the left eye. Magnetic resonance imaging (MRI) of the orbit demonstrated infiltration of orbital fat and the extra-ocular muscles. We performed transverse blepharotomy of the left eyelid to correct lagophthalmos; and during surgery, we took a biopsy sample from levator muscle and orbital fat. After the operation, the patient was able to close her eyelids, and epithelial problems were resolved. Biopsy revealed fibro-vascular, muscle and fat tissue infiltrated with minimally differentiated carcinoma cells. Breast examination revealed a nodule in the left breast. Biopsy of the mass confirmed the diagnosis of invasive breast carcinoma. Orbital manifestation of metastases, such as diplopia, lagophthalmos or pain may reduce life quality of the patients and must be evaluated on a multidisciplinary basis.

Diabetic retinopathy is the lead among causes of blindness in North America. Glucose-induced endothelial injury is the most important cause of diabetic retinopathy and other vascular complications. Extracellular signal-regulated kinase 5 (ERK5), also known as big mitogen-activated protein kinase 1 (BMK1), is a member of mitogen-activated protein kinases (MAPK) family. Physiologically, it is critical for cardiovascular development and maintenance of the endothelial cell integrity. Extracellular signal-regulated kinase 5 is protective for endothelial cells under stimulation and stress. Decreased activation of ERK5 results in increased endothelial cell death. Extracellular signal-regulated kinase 5 signaling may be subject to alteration by hyperglycemia, while signaling pathway including ERK5 may be subject to alteration during pathogenesis of diabetic complications. In this review, the role of ERK5 in diabetic macro- and microvascular complications with a focus on diabetic retinopathy are summarized and discussed.

Vertical heterophoria (VH) is the latent vertical misalignment of the eyes when the retinal images are dissociated, vertical orthophoria (VO) when there is no misalignment. Studies on postural control, during binocular vision in upright stance, reported that healthy subjects with small VH vs. VO are less stable, but the experimental cancellation of VH with an appropriate prism improves postural stability. The same behavior was recorded in nonspecific chronic back pain subjects, all with VH. It was hypothesized that, without refraction problems, VH indicates a perturbation of the somaesthetic cues required in the sensorimotor loops involved in postural control and the capacity of the CNS to optimally integrate these cues, suggesting prevention possibilities. Sensorimotor conflict can induce pain and modify sensory perception in some healthy subjects; some nonspecific pain or chronic pain could result from such prolonged conflict in which VH could be a sign, with new theoretical and clinical implications.