Horizontal Diplopia (Grand Rounds)

From EyeWiki


History of Present Illness

  • 43 Caucasian female with acute binocular horizontal diplopia worse on left gaze for 4 days
  • slight decrease visual acuity (VA) and soreness OS
  • pulsatile tinnitus left ear that decreased upon standing 3 weeks prior
  • no vertigo, dysarthria, numbness, weakness, headache nor stiff neck

Medical History

  • Pre menstrual syndrome (PMS)
  • Norethindrone/ethinyl estradiol
  • Factor V Leiden deficiency
  • Deep vein thrombosis (DVT) and pulmonary embolus(PE)
  • Laser-assisted in situ keratomileusis (LASIK) 2004
  • Bipolar disorder


quetiapine, clonazepam, coumadin



Ophthalmic History

Status post LASIK both eyes (2004)

Social History

  • Pharmaceutical sales representative
  • Married, does not drink, smoke or use illicit drugs

Family History

  • Mother diabetic retinopathy and migraine

Review of Systems

Otherwise negative except per history of present illness



  • OD: 20/20
  • OS: 20/20- (-1.25+0.50 x 145)

Color: 10/10 OU Pupils: no RAPD IOP:

  • 11 mmHg
  • 13 mmHg
  • SLE: small conjunctival hemorrhage inferiorly OS
  • Fundus: normal; no spontaneous venous pulsation OU
  • No audible bruit over the mastoids
  • No nystagmus
  • Normal coordination, gait and reflexes


  • OD : Small right hypertropia on left gaze
  • OS: 65-70% abduction
  • Esotropia (ET)
  • Primary: 25 PD
  • Left gaze: 35 PD
  • Right gaze: 5 PD
  • Upgaze: 25 PD
  • Downgaze: 20 PD

Humphrey Visual Field (HVF) 2/2/2011


Laboratory Results

  • PT: 21.0 (normal 12-14 seconds)
  • PTT: 36.0 9 (normal 18-28 seconds)
  • INR: 1.72 (normal 2-3)
  • D-Dimer: 203.0 (normal 50 – 192ug/L)

Head and Orbital Imaging Studies

Computed tomography (CT) and Magnetic resonance tomography (MRI) scans: “normal” but dental hardware caused artifact

Magnetic Resonance Venography (MRV) 2/4/2011: Coronal and Sagittal


Differential Diagnosis

Differential Diagnosis of Diplopia in this Case

  • Carotid-cavernous (C-C) fistula
  • Left 6th nerve palsy

Microvascular Trauma

  • Autoimmune

Thyroid related ophthalmopathy

  • Idiopathic intracranial hypertension falsely localizing 6th nerve
  • Schwannoma
  • Inflammatory

Neuro-sarcoidosis Orbital myositis Orbital pseudotumor

  • Infections

Tuberculosis Lyme disease Syphilis Cryptococcus

Follow Up Examination 3/3/2011

  • Stereo vision: nil even to fly
  • Proptosis: exophthalmometer

Base: 86 mm OD: 14 mm OS: 18 mm

  • Small dilated conjunctival vein inferiorly OS
  • Echography: dilated left superior orbital vein (SOV)

CT Angiogram


3-D Reconstruction


C-C Fistula

Carotid-cavernous fistulas (CC fistulas) may be direct or indirect

  • Direct CC fistulas (high flow CCFs) defect in the wall of the internal carotid artery (ICA) and cavernous sinus
  • Indirect CC fistulas (low flow CC fistulas) 35% of dural arterio-venous fistulas (dAVF).


Etiology: Three-stage hypothesis for the formation of dAVFs

Stage 1. Venous sinus thrombosis is the initial event possibly combined with other anatomic features that limit venous outflow, such as venous sinus stenosis

Stage 2. New microscopic fistulas within the wall of the venous sinus, connecting vaso vasorum to tiny venous tributaries, enlarge; result of a build-up of back pressure in the venous system, inflammatory changes in response to the thrombosis and/or an increase in angiogenic factor expression

Stage 3. Recanalization of the thrombosed venous sinus occurs; if only partial recanalization occurs, or if there is another venous sinus outflow obstruction (ex. venous sinus stenosis), arterial flow is diverted into the subarachnoid venous system (i.e., retrograde leptomeningeal flow occurs).

Clinical Features of�Indirect C-C Fistulas

  • Most patients are women in the sixth or seventh decade of life

Men comprise 25% of cases

  • Type D is most common
  • Slight propensity for the left side



  • May be bilateral
  • ECA: Branches of the internal maxillary, middle meningeal, accessory meningeal, ascending pharyngeal
  • ICA: Cavernous segment branches

Venous drainage

  • Highly variable
  • Impaired venous drainage is typical and enlargement of the superior ophthalmic vein is a frequent finding

Cortical venous drainage is present in 31–34% of cases

Inferior petrosal sinus (IPS) dAVF

  • A variant of cavernous dAVFs; accounts for some 3% of intracranial dAVFs *Presentation is similar to cavernous dAVFs.

Table 1: Clinical presentations of the 89 patients in this study

Types of clinical presentation

Number of


Headache 75
Proptosis 87
Chemosis 89
Diplopia 78
Visual deficit 23
Tinnitus 64
Seizure 5
Neurological deficits including cranial nerve deficit 39
Abnormalities of mentation 5
Intracranial bleed 4


Dural Arterio-venous Fistula in Setting of Factor V Leiden Deficiency

Kraus JA et al., found a significantly higher frequency of activated protein C resistance (APCR) and factor V Leiden in the patient group than among controls (5/22 vs. 0/22, P=0.048)


Manual compression

  • Technique: patient use the opposite hand (hemispheric ischemia failsafe) to locate carotid pulse just lateral to the trachea
  • Gradually increase pressure until pulse is stopped
  • Compression is maintained for 10–15 s at a time, 2–3 times an hour

Results: closure within mean of 41 days in 30% (range of minutes to 6 months)

Contraindications: cervical carotid artery disease (atherosclerosis, dissection), sick sinus syndrome, poor patient compliance

Indications for Intervention

Barrow et al., proposed the following indications:

  • Visual deterioration
  • Intolerable diplopia
  • Intolerable bruit or headache
  • or “malignant” proptosis with untreatable corneal exposure

The presence of retrograde cortical venous drainage

Trans-venous Embolization

Preferred method of treating indirect CC fistulas

  • Simple
  • High success rate

Cannulation pathways

  • IPS
  • Alternatively, the pterygoid venous plexus, superior petrosal sinus, facial vein, and superior ophthalmic vein can be used

Embolic materials of choice include (used in isolation or in combination)

  • Coils (can be redeployed intraoperatively)
  • n-Butyl cyanoacrylate (n-BCA) glue (permeable)
  • Ethylene vinyl alcohol copolymer (EVOH) (permeable)

Complete cure rate of indirect CC fistulas is 70–90% (complication rate of 2.3–5%)

Trans-arterial Embolization

Transarterial embolization of indirect low-flow CC fistulas

  • Cumbersome because of the small size, tortuous anatomy and multiplicity of arterial feeders

Coils and particulate agents can be used C*annot cause permanent occlusion of the fistula by themselves

  • Selective distal access into multiple tiny feeder vessels is often difficult
  • May require multiple sessions in a staged approach


  • Stereotactic radiosurgery: for indirect C-C fistulas, using CT and MRI, target irradiated to 30–40 Gy
  • Surgery: limited role with poor outcome

Post-operative Angiogram: AP view and Sagittal view


Post-embolization Angiogram



  • 43 year old female with C-C fistula simulating left 6th nerve palsy
  • Clinical judgment and imaging studies play important roles
  • Angiogram confirmed a complex left C-C fistula draining primarily through the left SOV
  • Trans-venous embolization is the treatment of choice; trans-arterial embolization is also effective


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  • Barrow DL, Spector RH, Braun IF, et al. Classification and treatment of spontaneous carotid-cavernous sinus fistulas. J Neurosurg 1985;62:248-256.
  • Barry RC, Wilkinson M, Ahmed RM, et al. Interventional treatment of carotid cavernous fistula. J Clin Neurosci 2011;18:1072-1079.
  • Friedman NJ, Kaiser PK. The Massachusetts Eye and Ear Infirmary: Illustrated Manual of Ophthalmology 3rd edition. Saunders, Elsevier, 2009.
  • Gemmete JJ, Ansari SA, Gandhi D. Endovascular Treatment of Carotid Cavernous Fistulas. Neuroimaging Clin N Am 2009;19:241-255.
  • Kraus JA, Stuper BK, Nahser H-C, et al. Significantly increased prevalence of factor V Leiden in patients with dural arteriovenous fistulas. Journal of Neurology 2000;247:521-523.