Biomedical subjects

Aki Kawasaki

Publications and source records attributed to Aki Kawasaki.

15 recordsLinked to original sources

PubMed2006

Phenotype of three consanguineous Tunisian families with early-onset retinal degeneration caused by an R91W homozygous mutation in the RPE65 gene.

PURPOSE: To identify the genetic defect, and to phenotype, three consanguineous Tunisian families presenting with early-onset retinal degeneration (EORD). METHODS: All accessible family members were included. They underwent blood sampling and ophthalmological examination including, when possible, full-field ERG and pupillometry. A genome-wide linkage analysis was initiated. Mutation analysis of the RPE65 gene within the linked interval was performed by bi-directional sequencing. RESULTS: Eleven out of 53 examined members were clinically affected with an EORD. Linkage analysis revealed a maximal lod score of 4.02 (theta=0.1) for the marker D1S207 on 1p31. Mutational screening of the RPE65 gene identified a homozygous R91W mutation co-segregating with the disease in all affected individuals. Eleven homozygotes had nystagmus and acuities ranging from CF to NLP. Two retinal patterns were identified: pattern 1 presented mid-peripheral deep white dot deposits and virtually no clumped pigmentation, whereas pattern 2 showed mid-peripheral pigmented clumps without any white deposits. Homozygotes had no detectable full-field ERG and an abnormal pupillary light reflex. Eleven heterozygotes had normal visual function. CONCLUSION: We identified and characterised an endemic form of early onset rod-cone dystrophy in a consanguineous population from northeastern Tunisia, due to the prevalence of a single RPE65 mutation. Two funduscopic patterns were identified: white dot deposits in earlier stages and clumped pigment in later stages.

Adult↗

PubMed2006

Optic neuropathy in patients using amiodarone.

OBJECTIVE: To refine the criteria for the diagnosis of amiodarone-related optic neuropathy by including a broader spectrum of clinical features, thus helping to differentiate this entity from nonarteritic anterior ischemic optic neuropathy coincidentally affecting a patient taking amiodarone. METHODS: A retrospective case review of 22 patients who developed optic neuropathy while taking amiodarone, in whom other systemic causes were excluded. RESULTS: We identified 3 groups of patients: those in whom a diagnosis of amiodarone-induced optic neuropathy seems probable (n = 14), those in whom an association with amiodarone optic neuropathy is indeterminate (n = 5), and those in whom the occurrence of nonarteritic anterior ischemic optic neuropathy seems to be coincidental (ie, unrelated to amiodarone) (n = 3). We formulated specific diagnostic criteria for each of these categories. CONCLUSIONS: We recommend a systematic approach that includes assessment of bilaterality, mode of onset, degree of optic nerve dysfunction, structure of the uninvolved optic disc in unilateral cases, and systemic toxic effects. Such well-defined diagnostic criteria can help the clinician in the treatment of patients with this disorder.

Aged↗

PubMed2006

Photophobia associated with a demyelinating lesion of the retrochiasmal visual pathway.

PURPOSE: To present two patients in whom photophobia was a predominant presenting symptom of retrochiasmal demyelination. DESIGN: Observational case report. METHODS: Two women who experienced an acute onset of photophobia underwent neuroophthalmic examination and investigations at a single institution. RESULTS: Examination revealed a homonymous visual field defect in both patients. Magnetic resonance imaging (MRI) demonstrated a hyperintense lesion in the area of the right posterior thalamus in one patient and enhancing lesions in the deep white matter of the temporal lobes bilaterally with contrast enhancement of the right optic tract in the second patient. Additional investigations, including lesion biopsy in the first patient, revealed demyelination as the most likely etiology. Improvement of photophobia, visual field defect, and radiographic abnormalities was documented over the next three to four months without accompanying treatment in both patients. CONCLUSIONS: Central pathology, including demyelination of the retrochiasmal visual pathway, should be considered in patients who experience acute photophobia.

Adult↗

PubMed2006

Origin of the relative afferent pupillary defect in optic tract lesions.

OBJECTIVE: To determine the percent decussation of pupil input fibers in humans and to explain the size and range of the log unit relative afferent pupillary defect (RAPD) in patients with optic tract lesions. DESIGN: Experimental study. PARTICIPANTS AND CONTROLS: Five patients with a unilateral optic tract lesion. METHODS: The pupil response from light stimulation of the nasal hemifield, temporal hemifield, and full field of each eye of 5 patients with a unilateral optic tract lesion was recorded using computerized binocular infrared pupillography. Six stimulus light intensities, separated by 0.5-log unit steps, were used; 12 stimulus repetitions were given for each stimulus condition. MAIN OUTCOME MEASURES: For each stimulus condition, the pupil response of each eye was characterized by plotting the mean pupil contraction amplitude as a function of stimulus light intensity. The percentage of decussating afferent pupillomotor input fibers was calculated from the ratio of the maximal pupil contractions elicited from each eye. The RAPD was determined pupillographically from full-field stimulation to each eye. RESULTS: In all patients, the pupil response from the functioning temporal hemifield ipsilateral to the tract lesion was greater than that from the functioning contralateral nasal hemifield. This temporal-nasal asymmetry increased with increasing stimulus intensity and was similar in hemifield and full-field stimuli, eventually saturating at maximal light intensity. The log unit RAPD did not correlate with the estimated percentage of decussating pupil fibers, which ranged from 54% to 67%. CONCLUSIONS: In patients with a unilateral optic tract lesion, the pupillary responses from full-field stimulation to each eye are the same as comparing the functioning temporal field with the functioning nasal field. The percentage of decussating fibers is reflected in the ratio of the maximal pupil contraction amplitudes resulting from stimulus input between the two eyes. The RAPD that occurs in this setting reflects the difference in light sensitivity between the intact temporal and nasal hemifields. Its magnitude does not correlate with the difference in the number of crossed and uncrossed axons, but its sidedness contralateral to the side of the optic tract lesion is consistent with the greater percentage of decussating pupillomotor input.

Adolescent↗

PubMed2006

Statin-associated myasthenia gravis: report of 4 cases and review of the literature.

A few recent individual case reports have suggested that a myasthenic syndrome may be associated with statin treatment, but this association is not well described. We report 4 patients who developed symptoms of myasthenia gravis within 2 weeks of starting treatment with a statin drug. In 1 case the drug appears to have exacerbated underlying myasthenic weakness, whereas in the other 3 cases, de novo antibody formation appears to be most likely. In each case, some degree of recovery followed discontinuation of the statin medication.

Aged↗

PubMed2006

Recovery of postoperative visual loss following treatment of severe anaemia.

A 29-year-old pregnant woman noted acute visual loss following emergent Caesarean section complicated by excessive uterine bleeding. Postoperative visual acuity was count fingers in both eyes. Funduscopic changes were consistent with a diagnosis of anaemia-associated ischaemic optic neuropathy and retinopathy. One month later, because of persistent anaemia and poor visual recovery, blood transfusion was given. Following transfusion, the patient's vision improved over the next 6 months. In an otherwise healthy patient, visual loss associated with postoperative blood loss may still be partially reversible with correction of the anaemia, even after a delayed period of time.

Adult↗

PubMed2005

Optic nerve massaging: an extremely rare cause of self-inflicted blindness.

PURPOSE: To report a patient whose self-inflicted blindness was not clinically apparent by history or external signs of trauma. DESIGN: Observational case report. METHODS: A 12-year-old girl with a history of social and behavioral problems was noted to have visual loss in her right eye. Examination revealed no light perception, optic nerve atrophy, partial upper lid ptosis, exotropia, and hypoesthesia of the cheek, all on her right side. RESULTS: After undergoing extensive examinations which were unrevealing for a diagnosis, the patient admitted to a recurrent maneuver, which she secretly used to relieve anxiety and stress. This maneuver consisted of inserting her index finger under the right supraorbital rim and forcibly subluxating her globe out of the orbital space. CONCLUSIONS: Self-inflicted visual loss can occur in nonpsychotic and nonviolent patients. Accurate diagnosis is important, as there is a risk of similar involvement to the fellow eye, and referral for psychiatric counseling is mandatory.

Blindness↗

PubMed2005

Neuro-ophthalmic emergencies for the neurologist.

A variety of acute neurologic disorders present with visual signs and symptoms. In this review the authors focus on those disorders in which the clinical outcome is dependent on timely and accurate diagnosis. The first section deals with acute visual loss, specifically optic neuritis, ischemic optic neuropathy (ION), retinal artery occlusion, and homonymous hemianopia. The authors include a discussion of those clinical features that are helpful in distinguishing between inflammatory and ischemic optic nerve disease and between arteritic and nonarteritic ION. The second section concerns disc edema with an emphasis on the prevention of visual loss in patients with increased intracranial pressure. The third section deals with abnormal ocular motility, and includes orbital inflammatory disease, carotid-cavernous fistulas, painful ophthalmoplegia, conjugate gaze palsies, and neuromuscular junction disorders. The final section concerns pupillary abnormalities, with a particular emphasis on the dilated pupil and on carotid artery dissection. Throughout there are specific guidelines for the management of these disorders, and areas are highlighted in which there is ongoing controversy.

Acute Disease↗

PubMed2004

Anterior ischemic optic neuropathy in eyes with optic disc drusen.

BACKGROUND: There have been anecdotal reports of anterior ischemic optic neuropathy (AION) occurring in eyes with optic disc drusen (ODD), but the clinical features of this condition have not been well characterized. OBJECTIVES: To better describe the clinical features of AION associated with ODD and to compare the clinical features of this condition with those of "garden variety" nonarteritic AION. METHODS: We reviewed the medical records of 20 patients who experienced an episode of AION in an eye with ODD. In 4 patients, both eyes were affected; thus, 24 eyes were studied. The diagnosis of ODD was made by ophthalmoscopic identification, orbital ultrasonography, or computed tomographic scanning. We recorded age, sex, vascular risk factors, symptoms, visual acuity, visual fields, and results of the follow-up examination in all patients. These findings were compared with data from previously reported series of patients with nonarteritic AION. RESULTS: Our 20 patients included 14 men and 6 women (age range, 18-69 years; mean, 49.4 years). Vascular risk factors were identified in 10 patients (50%). Three patients reported episodes of transient visual loss before their fixed deficit. The visual acuity at the initial examination was 20/60 or better in 15 (62%) of the 24 eyes; 8 had a visual acuity of 20/20. The predominant pattern of visual field loss was an altitudinal or arcuate defect in 19 (79%) and a centrocecal scotoma in 5 (21%) of the 24 eyes. There was subjective worsening of vision before the initial neuro-ophthalmic examination in 11 eyes (46%) and objective documentation of progression in 7 eyes (29%). The final visual acuity was 20/40 or better in 13 (62%) of 21 eyes and 20/200 or worse in 3 (14%) of 21 eyes. CONCLUSIONS: Our patients were strikingly similar to those with nonarteritic AION unassociated with drusen in regard to prevalence of vascular risk factors, pattern of visual field loss, and occurrence of a subsequent similar event in the fellow eye. In contrast, however, patients with ODD-AION were younger than those with nonarteritic AION, were more likely to report preceding episodes of transient visual obscuration, and enjoyed a more favorable visual outcome.

Adolescent↗

PubMed2003

Idiopathic recurrent neuroretinitis: effects of long-term immunosuppression.

OBJECTIVE: To determine the efficacy of long-term immunosuppressive therapy in patients with recurrent idiopathic neuroretinitis. METHODS: A retrospective review of 30 patients with recurrent idiopathic neuroretinitis identified 7 who received ongoing immunosuppression with prednisone and/or azathioprine for whom adequate follow-up information was available. We calculated the number of attacks per unit of time for each patient before and after treatment to derive mean attack rates for the group. RESULTS: For the entire group, we found a rate of 0.58 attacks per year prior to the initiation of immunosuppressive treatment, which decreased to 0.16 attacks per year following immunosuppression. This represents a reduction in the attack rate of 0.41, or a 72% decrease in attack frequency. CONCLUSIONS: Our study suggests a possible role for long-term immunosuppressive treatment in patients with recurrent idiopathic neuroretinitis. A longer follow-up interval, more standardized treatment regimens, and additional outcome measures might reveal a greater benefit of treatment.

Adult↗

PubMed2003

An unusual presentation of herpes zoster ophthalmicus: orbital myositis preceding vesicular eruption.

PURPOSE: To present a case of orbital myositis associated with herpes zoster ophthalmicus. DESIGN: Observational case report. METHODS: A 47-year-old woman with acute retrobulbar eye pain and diplopia preceding the vesicular rash of herpes zoster ophthalmicus was evaluated and treated. RESULTS: Magnetic resonance imaging showed enlargement and enhancement of extraocular muscles consistent with an inflammatory myopathy. Following acyclovir and prednisone treatment, all symptoms resolved, and neuralgia did not develop. CONCLUSIONS: Herpes zoster may cause symptoms and signs of orbital myositis before eruption of cutaneous skin lesions and thus should be considered in the differential diagnosis of an acute orbital myositis.

Acyclovir↗

PubMed2003

The natural history of untreated skull base meningiomas.

BACKGROUND: This study was undertaken to determine the natural history of untreated skull base meningiomas. Although there are reports on the natural history of meningiomas, most series contain only a few cases of meningiomas involving the skull base. Natural history information is important when recommending treatment and evaluating results. METHODS: The case records and imaging studies of 40 patients with skull base meningiomas from a single practice were reviewed. These patients either did not receive treatment or there was a long delay from the onset of symptoms to the initiation of treatment. RESULTS: Skull base meningiomas may be very indolent tumors. Patients with these tumors have lived long, comfortable, and relatively productive lives without treatment or with delayed treatment. Impairment may be much less than imaging studies would suggest. CONCLUSION: The authors are not advocating that skull base meningiomas not receive treatment. However, their unique experience with this group of patients provides convincing evidence that the indolent behavior of some skull base meningiomas must be considered when recommending various surgical and radiation procedures and interpreting their results in relationship to the functional outcome of the patient.

Adult↗

PubMed2002

Long-term prognosis in patients with vasculopathic sixth nerve palsy.

PURPOSE: To better define the long-term prognosis in patients with a vasculopathic sixth nerve palsy (6NP), specifically addressing the degree of recovery and incidence of recurrent similar episodes. DESIGN: Observational case series. METHODS: Retrospective chart review. SETTING: An outpatient neuroophthalmic practice. STUDY POPULATION: Patients with one or more vascular risk factors and an acute, isolated 6NP that spontaneously recovered. OBSERVATION PROCEDURE: Information regarding resolution of the 6NP, subsequent vascular events and recurrent ocular motor nerve palsy was obtained from chart review of follow-up clinic visits, mailed questionnaires and telephone interviews. The duration of follow-up ranged from 2 to 13 years. MAIN OUTCOME MEASURES: Resolution of 6NP (complete or incomplete) and incidence of recurrent ocular motor nerve palsy. RESULTS: Fifty-nine patients were identified with a mean age of 65.3 years +/- 11.6 (range 34-90 years). Fifty-one patients (86%) experienced complete resolution of their first episode of vasculopathic 6NP and eight patients (14%) had incomplete resolution. A subsequent episode of ocular motor mononeuropathy occurred in 18 of 59 (31%) patients. The number of recurrences ranged from one (in 14 patients) to four (in one patient). There was no association between any risk factor and recurrence of ocular motor nerve palsy. Similarly, incomplete resolution of the vasculopathic 6NP was not associated with any risk factor. CONCLUSIONS: Patients with a vasculopathic 6NP usually have complete resolution of their ophthalmoplegia, but nearly one third of patients in our study later experienced at least one episode of recurrent vasculopathic ocular motor nerve palsy.

Abducens Nerve Diseases↗

PubMed2002

Photophobia as the presenting visual symptom of chiasmal compression.

Five patients with a chief visual complaint of photophobia were subsequently found to have compressive lesions of the optic chiasm. Visual acuity and visual field deficits were often subtle. Magnetic resonance imaging scanning revealed large suprasellar masses, including three pituitary adenomas, a craniopharyngioma, and a clivus chordoma. Photophobia resolved in all patients following treatment of the tumors. A compressive lesion of the optic chiasm should be considered in patients who experience persistent photophobia unexplained by ocular abnormalities.

Adenoma↗

PubMedDate not supplied

Jumping Jack Flash.

A 38-year-old woman presented with blurred vision and "jumping" of the right eye for 7 months. Magnetic resonance imaging of the head was normal. Intermittent intorsion of the right eye was noted on examination, consistent with superior oblique myokymia. She was initially treated with carbamazepine but stopped after becoming light-headed. The diagnosis and treatment of superior oblique myokymia are discussed.

Adult↗