With careful planning, complications may be minimized. Advances in viscoelastics, sutured capsular tension rings (CTRs) or segments, and phacodynamics now make such surgery possible. In the recent past, such cases were typically associated with a significant risk of intra- and postoperative complications. José Ignacio Barraquer: The Father of Refractive Surgeryįrom Keratomileusis to LASIK: A Short HistoryĪnterior segment surgery involving a cataract in eyes such as the case we present hereina fixed dilated pupil, significant lens subluxation, anterior capsular fibrosis, zonular dialysis, and vitreous prolapse into the anterior chamberposes a significant challenge. If cerebral blood flow and cerebral perfusion pressure can be rapidly restored in the patient with severe head injury who has dilated pupils, the prognosis may be good.Torsional Ultrasound: What is its Impact After 1 Year on the Market?Ī Subluxated Traumatic Cataract With a Fixed Dilated PupilĬorneal Inlays: A Surgical Correction of Presbyopia More important, pupil dilation may be an indicator of ischemia of the brain stem. These findings suggest that pupillary dilation is associated with decreased BBF and that ischemia, rather than mechanical compression of the IIIrd cranial nerve, is an important causal factor. Unfavorable outcome at 12 months was directly related to age (P = 0.062) and inversely related to pupillary responsiveness (P = 0.0006), pupil size (P = 0.005), and BBF of less than 40 ml/100 g/min (P = 0.009). Intracranial pressure and the presence of a brain stem lesion observed on the computed tomographic scan did not correlate with BBF, pupillary size, or reactivity. In patients with bilaterally nonreactive pupils, the BBF was 30.5+/-16.8 ml/100 g/min, and in those with normally reactive pupils, the BBF was 43.8+/-18.7 ml/100 g/min (P < 0.001). One hundred sixty-two patients with a Glasgow Coma Scale score of 8 or less underwent stable xenon computed tomographic blood flow determination at the level of the superior colliculus, and this blood flow was correlated with pupillary features, intracranial pressure, computed tomographic scan pathology, and outcome.Ī BBF of less than 40 ml/100 g/min was significantly associated with poor outcome (P < 0.009). We determined the relation of BBF to outcome and pupillary response in patients with severe head injuries. Therefore, we have tested an alternative hypothesis that a decrease in brain stem blood flow (BBF) is a more frequent cause of mydriasis and brain stem symptomatology after severe head injury. However, not all patients with herniation have fixed and dilated pupils, and not all patients with nonreactive, enlarged pupils have uncal herniation. Pupil dilation is thought to be the result of uncal herniation causing mechanical compression of the IIIrd cranial nerve and subsequent brain stem compromise. Acute pupillary dilation in a head-injured patient is a neurological emergency.
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