Abstract
Purpose:
To present an evaluation of the pineal gland through PSG in a patient with juvenile X linked retinoschisis due to the mutation c421C>T:pR141C in the RS1 gene, once the protein retinoschisin is not only found in the retina, but also at the pineal gland, which is involved in sleep control.
Methods:
Eye examination was performed. Best corrected visual acuity (BCVA) was done (Snellen chart). Fluorescein angiography (TRC50DX Topcon) and Spectralis optical coherence tomography-OCT (Heidelberg Engineering Inc) was done. gDNA was PCR amplified for exons 1-6 and flanking splice sites of RS1. Bidirectional sequence was analyzed and compared to the NCBI reference sequence NM000330.3. The result was confirmed by restriction fragment digest with the enzyme Hhal. PSG was made in a 32 channel (ch) digital device with 16 activated ch: 4EEG, 2EOG, 1ECG, 2EMG, 1 nasal air flow, 1 oral air flow, 2 respiratory belts, 1 oximetry, 1 microphone, 1 positional monitor, and 2 ear lobe references.
Results:
Eye fundus revealed macular edema with a spoke-wheel pattern, on both eyes. The OCT showed foveal retinoschisis with confluent cysts, that were linked to increased retinal thickness. The RS1 sequencing revealed the mutation c421C>T:pR141C. PSG exhibited a full recording time of 561min and a total sleeping time of 427min. Sleep efficiency was 76% (normal value NV≥85%). Sleep architecture was fragmentated with 15 awakenings (NV<10/night) and increased microawakenings after sleep onset (12/h NV<10/h), these triggered mostly by respiratory obstructions (RO). The nonrapid eye movement (NREM) sleep latency was increased (33min NV 10-20min), as well as the rapid eye movement (REM) sleep latency (201min NV 70-140min). There was a percentage distribution change of sleep stages, with prolonged NREM surperficial sleep and reduced REM and deep NREM sleep. We recorded 113 apneas, 18 hypopneas, respiratory events with a maximum duration of 35s, followed by oxyhemoglobin (OHb) desaturation of up to 58%. The apnea/hypopnea index was augmented (18/h NV < 5/h). Baseline OHb saturation was 98%, the average was 96%, and the minimum was 58%. We recorded frequent snoring of moderate intensity. The ECG arrhythmias weren’t associated with RO.
Conclusions:
PSG showed alterations that could be explained by the dysfunctional retinoschisin in the pineal gland, suggesting an additional role for this protein, besides its retinal function.
Keywords: 688 retina •
494 degenerations/dystrophies •
539 genetics