SHAKEN BABY SYNDROME

Shaken baby syndrome (SBS) is a term used to describe a type of child abuse associated with severe ocular and systemic injuries but few if any external signs of abuse. The ophthalmologist’s role in such cases is to document all ocular findings and note whether these findings are consistent with SBS. While no single ocular manifestation is pathognomonic of child abuse, ocular examination can provide significant and compelling information leading to the diagnosis.

Symptoms

The shaken baby may present to the emergency room in a comatose state from severe intracranial injuries. The alert child may have decreased visual function as indicated by inattentiveness to visual targets. The child may be irritable or agitated. Children may also present with seizure, failure to thrive, lethargy, vomiting, and respiratory difficulties.

Clinical Features

The child may have no signs of external trauma. Alternatively, the external ocular examination may reveal periorbital ecchymosis, eyelid lacerations, subconjunctival hemorrhages, corneal abrasions, hyphema, iris sphincter tears, and cataract.

Fundus features of SBS include extensive intraretinal, preretinal, and/or subretinal hemorrhages. Intraretinal hemorrhages occur throughout the entire retina, extending from the optic disc to the ora serrata. The preretinal hemorrhages and sub-internal limiting membrane hemorrhages are often round and dome shaped. Other fundus findings associated with acute SBS include vitreous hemorrhage, optic nerve swelling, retinal folds, retinoschisis, retinal dialysis or tears, and chorioretinal scars from previous trauma. While any of these retinal findings may occur in the SBS, none is pathognomonic.

Ancillary Testing

Ultrasonography may be useful in children with severe vitreous hemorrhage.

Pathology/Pathogenesis

Repeated acceleration-deceleration injury to the shaken infant may be the cause of the retinal hemorrhages, retinal folds, and retinoschisis seen in SBS. Bleeding may derive from vitreoretinal traction, in which the vitreous pulls on the retina and retinal blood vessels during rapid deceleration. Sudden shifts in intracranial venous pressure from chest trauma or head trauma may be a contributing factor.

Treatment/Prognosis

Treatment for the retinal hemorrhage is usually supportive. However, if a child has a large, nonclearing vitreous or preretinal hemorrhage that obstructs central vision, vitrectomy surgery should be considered to minimize amblyopia. In SBS, approximately 15% of infants die, 50% have significant morbidity, and 20% of survivors have poor vision. The causes of visual defects are more often lesions of the occipital cortex than the intraocular injuries. In terms of prognosis, mortality is correlated with the extent of visual loss and the area of retinal hemorrhages.

Systemic Evaluation

In a child under 3 years of age, the presence of retinal hemorrhages raises the possibility of child abuse and must be investigated. Ancillary testing is typically directed by the pediatrician. Testing may include neuroimaging to rule out associated central nervous system involvement such as subdural hematoma and subarachnoid hemorrhage and a careful radiographic search for bone fractures or other skeletal injuries. To exclude other causes of retinal hemorrhages, an appropriate workup includes (1) history taking regarding possible accidental trauma; (2) hemophilia; (3) von Willebrand’s disease;

(4) coagulopathies; and (5) vitamin K deficiency. The relationship between cardiopulmonary resuscitation and intraretinal hemorrhages is controversial.

Shaken baby syndrome is characterized by widespread intraretinal hemorrhages, which are usually bilateral but may be unilateral or asymmetric.

This infant had bilateral widespread intraretinal hemorrhages. In addition, an area of retinoschisis (upper left) is observed.

This child with shaken baby syndrome had vitreous hemorrhage obscuring the retinal details. Several whitecentered intraretinal hemorrhages are present.

The fellow eye of the same patient demonstrates evidence of a traction retinal fold, which results from the strong relationship of the vitreous and the perimacular area in the young.

TERSON’S SYNDROME

Terson initially reported on the association of vitreous hemorrhage with an acute subarachnoid hemorrhage. Since then, Terson’s syndrome has been applied to any form of intracranial hemorrhage with secondary vitreous or preretinal hemorrhage.

Symptoms

Patients with Terson’s syndrome generally present to the ophthalmologist after an acute intracranial event, usually a ruptured intracranial aneurysm or a subdural hematoma. Patients are frequently obtunded initially and are not able to complain of acute visual loss. The ophthalmologist is often consulted when the patient regains consciousness and complains of poor vision or central scotoma. The visual loss may be unilateral or bilateral at presentation and typically ranges from 20/400 to light perception.

Clinical Features

The hemorrhages in this syndrome are localized to the sub-internal limiting membrane space of the macula or peripapillary region. These hemorrhages may break through into the vitreous and may or may not clear spontaneously. In general, there is no relative afferent pupillary defect unless there has been optic nerve damage from direct trauma or intracranial injury.

Ancillary Testing

No ancillary testing is necessary. Fluorescein angiography demonstrates hypofluorescence corresponding to the areas of preretinal hemorrhage.

Pathology/Pathogenesis

A rapid increase in intracranial pressure leading to impaired intraocular venous return is the most likely cause of the preretinal hemorrhage. The sudden rise in intracranial pressure due to intracranial hemorrhage or trauma may cause intraocular venous stasis, which in turn causes the superficial retinal capillaries to rupture. The resulting hemorrhage is typically within the subinternal limiting membrane space.

Treatment/Prognosis

Many mild cases of preretinal hemorrhage, particularly those not involving the fovea, will resolve spontaneously. Larger hemorrhages that obscure the macula or result in nonclearing vitreous hemorrhage may require pars plana vitrectomy surgery. Removal of the internal limiting membrane can be performed without subsequent injury to the underlying neurosensory retina, and the blood can be easily evacuated. Surgical intervention can be delayed until the patient is medically and neurologically stable. The prognosis is generally good unless there has been hemorrhagic detachment of the neurosensory retina. In small children, failure to clear a large preretinal hemorrhage or a vitreous hemorrhage in a reasonable time period could lead to deprivation amblyopia of the affected eye.

Systemic Evaluation

Neurologic evaluation and imaging is urgent if hemorrhage of the sub-internal limiting membrane or spontaneous vitreous hemorrhage is noted in a conscious patient complaining of headache. An evaluation for bleeding tendencies or blood dyscrasia also may be warranted.

Terson’s syndrome in a 35-year-old woman following a spontaneous subarachnoid hemorrhage. She had bilateral preretinal and vitreous hemorrhages.

Preretinal and intraretinal hemorrhages in a patient with a ruptured intracranial aneurysm.

The preretinal hemorrhages were confined to the peripapillary and macular regions.

Severe preretinal and intraretinal hemorrhages in a patient with subarachnoid bleeding.