You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
abducens nerve palsy is the most common of the ocular paresis in adults,1 , 2 with sudden onset of binocular horizontal diplopia as the bothersome symptom .
sixth cranial nerve palsies can be secondary to etiologies such as vascular , viral illness , inflammation , trauma , and undetermined in few cases . in younger patients
the incidence of idiopathic sixth nerve palsies varies between 9.3 and 13.2/100,000 in the caucasian population , with idiopathic reasons contributing to 26% of the total incidence .
this case report deals with an acute onset esotropia due to abducens nerve paresis in a 25 year young adult presumably due to an idiopathic etiology or a viral illness .
the natural history of the clinical presentation , findings , and role of vision therapy is emphasized through this case report .
a 25-year - old male presented with chief complaint of sudden onset , binocular horizontal , uncrossed diplopia during the past 1 week associated with eye pain in right eye .
he also complained of vomiting and a radiating headache precipitated by stress , computer work and other near work .
there was no history of significant systemic illness or any ocular or head injury , and he denied any recent viral illness .
the local ophthalmologist had administered a 10-day course of intravenous methyl prednisolone injection along with tablet prednisolone 5  mg ( 10 tab / day ) for three days .
cover test revealed a 35 prism diopter right esotropia at distance and a 25 prism diopters right esotropia at 40  cm .
ocular motility showed mild restriction of abduction ( 1 ) in the right eye and rest of the movements were full .
mri brain results ( plain and contrast ) were within normal limits and no lesions / demyelination were identified .
binocular vision assessment revealed poor stereopsis , normal monocular accommodation , unmeasurable fusional vergence due to constant diplopia and reduced monocular accommodative facility and gradient ac / a ratio of 4:1 . the diagnostic data is provided in table 1 . due to constant diplopia and poor fusional ranges ,
the patient could fuse with 40 base - out fresnel prisms in front of the right eye . as the patient was a frequent traveler he preferred using frosted glasses instead of fresnel prisms .
at the 3 month follow - up , diplopia had reduced considerably except in extreme right gaze .
the frequency of the diplopia decreased , although diplopia persisted in right gaze , and this was stable for the past one month with no improvement noticed by the patient .
visual acuity was 20/20 , n6 in both the eyes and worth four dot test showed fusion for distance and near .
the cover test revealed a 16 pd esophoria at distance and 10 pd esophoria at near .
however , there were still significant reduced negative fusional vergence , and accommodative facility ( table 1 ) .
although there has been considerable improvement probably due to spontaneous recovery , the nfv amplitudes and accommodative facility were still reduced and the patient was symptomatic . considering no significant improvement over the past month , vision therapy was recommended to improve divergence amplitudes and to improve accommodative facility .
three broad goals were established for vision therapy , developing divergence amplitudes for distance and near , improving accommodative facility ( monocularly and binocularly ) , and improving saccadic / pursuit eye movements ( due to diplopia in lateral gaze ) . on re - assessment at the end of 10 sessions , asthenopic symptoms were reduced , and no diplopia was noticed for distance and near .
the distance and near angles reduced significantly from 16 pd esophoria to orthophoria for distance and 2 pd esophoria at near .
the goals of vision therapy and details of vision therapy is sequenced in table 2 , table 3 respectively .
after 10 sessions of in - office vision therapy , he was advised to continue home - based therapy using the transparent eccentric circles , life saver card , brock string and accommodative flippers .
a six month follow - up revealed stable alignment , and no symptoms with good compliance to home vision therapy .
the most common causes for non - traumatic sixth nerve paresis in children and adults include central nervous system mass lesions , demyelination and inflammation , vasculopathy , and multiple sclerosis.5 , 6 idiopathic presentations in adults can account for up to 22% of cases .
spontaneous recovery of 6 nerve paresis is common ( in almost 71% of affected individuals ) in traumatic sixth nerve palsy at 6 months after onset,7 , 8 , 9 and the angle of deviation is the most important determining the prognosis . in our case ,
vision therapy improved the patient 's range of fusion and thus significantly reduced the incidence of diplopia in both these patients .
saccadic peak velocities and latency are documented to be affected in sixth nerve palsies and hence saccadic training was thought to be constructive to improve saccades especially toward the paretic side .
though there is absence of quality data to suggest eye movement therapy may be helpful , from a physiological perspective we considered that this could be beneficial in preventing secondary contracture of the extraocular muscles .
also it has been well documented in literature that a high percentage of patients with a 6th nerve palsy show spontaneous remission that may take months .
thus , aggressive optometric treatment with prism , lenses , and vision therapy can help the patient be more comfortable during the time it takes for remission to occur , and also speed up the improvement in function . though it could be argued that the natural history would allow for spontaneous resolving of symptoms even without active intervention , our case emphasizes the short course of vision therapy that could be of potential benefit and immediate relief to visually bothering symptoms of diplopia and asthenopia .
vision therapy plays a significant role in improving fusional ranges , reduce asthenopic symptoms , and improve eye movements , thereby meeting the visual demands of the patient in idiopathic abducens nerve paresis .
thorough neurological investigations are required to rule out life threatening illness before commencing the therapy .
the natural history of idiopathic abducens nerve paresis and the role of conservative management such as vision training during the recovery process is not well documented in the literature to the best of our knowledge . 
 this case report presents the natural recovery process of idiopathic abducens nerve paresis in a young adult and the role of vision therapy in the recovery process .