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Dissociated Vertical Deviation (DVD) DJO Vol. 20, No.4, April-June, 200 Major Review Dissociated vertical deviation (DVD) Shailesh1, Rohit Saxena2, Ravindranath H.M.3 Consultant, Shekar Nethralaya, Bangalore, 2Associate Prof, Dr R P Center, AIIMS, New Delhi 3Director, Drishti speciality eye Hospital, Davangere Dissociated vertical deviation (DVD) is a poorly Diagnostic tests: understood eye motility disorder of unexplained When the eye is covered, it elevates and excycloducts; etiology. DVD is a form of cyclovertical deviation upon removal of cover, the elevated eye returns to which is known by various terms like, alternating the midline slowly along with incycloduction. These hypertropia, double hypertropia, dissociated vertical torsional movements can be observed by looking into divergence and alternating sursumduction amongst the conjunctival vessels. others.Bielschowsky provided the first comprehensive • Translucent occluder test (Spielmann’s) figure 1a-c description and clinical analysis of DVD. In – updrift of the eye behind the occluder can be seen DVD, either eye elevates when the fellow eye is and its downward slow drifting back is observed after fixating. Lancaster2 and swan called it alternating removing the occluder. sursumduction, emphasizing the monocular nature of • Graded density filter bar (Bielschowsky’s) test – as the movement. the density of the filter bar is increases, the eye drifts up and as the density of the filter bar is decreased, Clinical features: the eye comes down. This is called Bielschowsky’s The characteristic feature seen in DVD is the phenomenon. figure 2 spontaneous drifting of either eye upward when the • Red filter test – this is a dissociating test. The eye patient is tired or after covering one eye. After the behind the filter drifts up and patient appreciates cover is removed from the elevated eye, it slowly diplopia, with the red image being lower. The amount drifts downward to settle in the primary position. of separation between the images is used to measure Other features of DVD include: the amplitude of elevation of each eye. - Excycloduction of the elevated eye. Quantitative assessment of DVD can be made by - Incycloduction of the fixating eye. using base-down prisms, held under the occluder - Sometimes only excycloduction is seen under cover, in front of the nonfixating eye until the downward when it is called as Dissociated Torsional Deviation fixation movement of that eye is neutralized. (DTD). - Latent nystagmus seen in nearly half the patients - Head posture: anomalous head posture is reported in about 30% of patients.3,4 Anomalous head posture decreases the magnitude of alternating hyperphoria. Chin depression can also be seen. - DVD can occur with overaction of inferior oblique as well as superior oblique muscles. - It is rarely seen in infants, but usually presents at 2-5 years of age. - DVD is usually bilateral and asymmetrical. Unilateral cases are commonly associated with deep amblyopia and sensory heterotropia. - DVD is associated with infantile esotropia/ exotropia, and less commonly with Duane’s retraction syndrome. Figure 1-a No deviation in primary position 9 Dissociated vertical deviation (DVD) DJO Vol. 20, No.4, April-June, 200 Aetiology:Figure 1-b LeftNumerous eye DVD- showing theories elevation have of been left eye proposed Figure to 1-c explain No DVD this in the intriguing right eye when anomaly. the left eye is underElastic translucent preponderance occluder when of the right elevator eye is fixatingor the depressor muscles5; pareticfixating factors6 Aetiology:especially bilateral paresis of the depressor muscles and imbalances between the amount Numerousof innervation theories originating have been fromproposed each to vestibularexplain binocular organ have stimulation been proposed9. But it does earlier. not account for thisAbnormal intriguing visual anomaly. pathway Elastic preponderancerouting similar of theto albinismDVD in orpatients abnormal, with otherwiseintermittent normal & binocular elevatoralternate or excitationthe depressor of musclessubcortical5, paretic centers factors coul6 dfunctions. be responsible. Several investigators Recent investigations have opined that also the especiallyagree with bilateral Bielschowsky’s paresis of the verticaldepressor vergence muscles signalvertical theory vergence on movements DVD.7,8 Spielmannmust be predominantly andassumed imbalances that betweenDVD is the caused amount by of an innervation imbalance mediatedof binocular by oblique stimulation muscles.9. 0,But Aetiology it does notof DVD originatingaccount forfrom DVD each in vestibular patients organwith otherwisehave been normalstill remains binocular obscure, functions. but Bielschowsky’s Several explanation proposedinvestigators earlier. have Abnormal opined visual that pathway the vertical routing vergence of DVD movements as a vertical vergencemust be eye predominantly movement appears similarmediated to albinism by oblique or abnormal, muscles. intermittent10,11 Aetiology & alternate ofmore DVD convincing. still remains obscure, but excitationBielschowsky’s of subcortical explanation centers could of beDVD responsible. as a vertical vergence eye movement appears more Recentconvincing. investigations also agree with Bielschowsky’s Differential diagnosis: vertical vergence signal theory on DVD.7,8 Spielmann DVD should be differentiated from inferior oblique assumedDifferential that DVD diagnosis: is caused DVD by an should imbalance be differentiated of overaction, from (Table inferior ) oblique overaction, but has different features which are listed below. Table 1 Differences betweenDifferences DVD between and IOOA DVD and (Inferior IOOA (Inferior oblique oblique overaction) overaction) Features DVD IOOA 1) Hypertropia Same in primary position, Maximal in adduction, adduction & abduction never in abduction 2) Recovery movement on uncovering Slow downward drift Quick refixation 3) Superior oblique action May overact Usually underaction 4) V pattern Absent Often present 5) Pseudoparesis of Absent Present contralateral superior rectus 6) Incycloduction on Present Absent refixation 7) Latent nystagmus Often present Absent 8) Bielschowsky’s Often present Absent phenomenon 9) Red filter test Red image is always lower Red image is higher or as eye behind the filter is lower on alternation always higher 0 Dissociated vertical deviation (DVD) DJO Vol. 20, No.4, April-June, 200 Treatment: Many surgical modalities have been tried References: with varying success rates. Noorden GK Von. Binocular vision and ocular motility • Superior rectus recession – unconventional : theory and management of strabismus. St. Louis : Mosby recession of superior rectus by 7 to 9mm is required Year Book, Inc 2002; 378. in bilateral DVD. Asymmetric cases need differential 2. Lancaster WB. Factors underestimated, features recession2. overemphasized, and comments on classification. In Allen • Retroequatorial myopexy of superior rectus JE, ed: Strabismus Ophthalmic Symposium. St Louis, (Faden operation) – done along with superior rectus Mosby-year book, 958:430. recession may give better results. 3. Crone RA. Alternating hypertropia. Br J Ophthalmol, • Resection of inferior rectus – is done rarely as a 954;38:592. single surgery. It is usually done as second surgery 4. Bechtel RT, Kushner BJ, Morton GV. The relationship when superior rectus recession fails. between DVD and head tilts. J Pediatr Ophthalmol • Anterior transpositioning of inferior obliques – is Strabismus. 996;33:303. popular among few surgeons and effective in cases 5. Schweigger C. Die erfolge der schieloperation. Arch of DVD with inferior oblique overaction.3,4 The Augenheilkd. 30;895:65. antielevation syndrome which is observed after this 6. Duane A. binocular movements. Arch Ophthalmol. surgery in some cases can be overcome by bunching 933;9:579. the placement of inferior oblique adjacent to the 7. Bielschowsky A. Disturbances of the vertical motor inferior rectus. muscles of the eyes. Arch Ophthalmol.938;20:75. Lim5 has described hypotropic DVD, which is 8. Cheeseman EW, Guyton DL. Vertical fusional mostly unilateral and commonly is associated with vergence. The key to dissociated vertical deviation. Arch monocular visual deficits or high myopia. Although Ophthalmol. 999;7:88. the nature of the intermittent slow downward ocular 9. Spielmann A. A translucent occluder for studying deviation is similar to that of hypertropic DVD, eye position under unilateral or bilateral cover test. Am it should be considered to be a unique form of the Orthopt J. 986; 36:65. dissociated strabismus complex. This rare condition 0. Guyton D. Dissociated vertical deviation. An can be corrected surgically by a large recession or a exaggerated normal eye movement used to damp combined recession-resection of the inferior rectus cyclovertical nystagmus. Trans Am Ophthalmol Soc. muscle. 998;96:389. Fixating eye penalization with % atropine has been . Rijn LJ, Collewijn H. Eye torsion associated with shown by few authors to reduce DVD magnitude and disparity-induced vertical vergences in humans. Vision decompensatory phases during follow-up. Res. 994;7:2307. 2. Esswein MB, Noorden GK von, Coburn A. Comparison of surgical methods in the treatment of dissociated vertical deviation. Am J Ophthamol. 992;3:287. 3. Burke JP, Scott WE, Kutschke PJ. Anterior transposition of the inferior oblique muscle for dissociated vertical deviation. Ophthalmology. 993;00:245. Bielschowsky phenemenon: When the fixing eye is 4. Black BC. Results of anterior transposition of the presented with
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