John Grigg | The University of Sydney (original) (raw)
Papers by John Grigg
Investigative Ophthalmology & Visual Science, 2007
Clinical & Experimental Ophthalmology, 2012
Glaucoma is a sight-threatening disease affecting 3% of the population over the age of 50. Glau... more Glaucoma is a sight-threatening disease affecting 3% of the population over the age of 50. Glaucoma is treatable, and severe vision loss can usually be prevented if diagnosis is made at an early stage. Genetic factors play a major role in the pathogenesis of the condition, and therefore, genetic testing to identify asymptomatic at-risk individuals is a promising strategy to reduce the prevalence of glaucoma blindness. Furthermore, unravelling genetic risk factors for glaucoma would also allow a better understanding of the pathogenesis of the condition and the development of new treatments. The Australian and New Zealand Registry of Advanced Glaucoma is a prospective study that aims to develop a large cohort of glaucoma cases with severe visual field loss to identify novel genetic risk factors for glaucoma blindness. Clinical information and blood are collected from participants after referral by eye practitioners. Samples are collected across Australia and New Zealand using postage kits. Our registry has recruited just over 2000 participants with advanced glaucoma, as well as secondary and developmental glaucomas. A positive family history of glaucoma is present in more than half of the advanced glaucoma cases and the age at diagnosis is significantly younger for participants with affected relatives, which reinforces the involvement of genetic factors in glaucoma. With the collection of glaucoma cases recruited so far, our registry aims to identify novel glaucoma genetic risk factors to establish risk profiling of the population and protocols for genetic testing.
Twin Research and Human Genetics, 2008
Nutrition reviews, 2015
Age-related macular degeneration (AMD) causes a significant proportion of visual loss in the deve... more Age-related macular degeneration (AMD) causes a significant proportion of visual loss in the developed world. Currently, little is known about its pathogenesis, and treatment options are limited. Dietary intake is one of the few modifiable risk factors for this condition. The best-validated therapies remain oral antioxidant supplements based on those investigated in the Age-Related Eye Disease Study (AREDS) and the recently completed Age-Related Eye Disease Study 2 (AREDS2). In this review, current dietary guidelines related to AMD, along with the underlying evidence to support them, are presented in conjunction with current treatment recommendations. Both AREDS and AREDS2 are discussed, as are avenues for further research, including supplementation with vitamin D and saffron. Despite the considerable disease burden of atrophic AMD, few effective therapies are available to treat it, and further research is required.
BMJ case reports, 2011
Both intracranial hypertension and keratoconus may be associated with visual impairment. The auth... more Both intracranial hypertension and keratoconus may be associated with visual impairment. The authors present a case of a young female with poor right vision that did not improve despite treatment of her intracranial hypertension. Ophthalmic consultation diagnosed keratoconus as the cause.
Australian and New Zealand journal of ophthalmology, 1998
To improve the performance of visual-evoked potentials (VEP) in the assessment of the human visua... more To improve the performance of visual-evoked potentials (VEP) in the assessment of the human visual field, the multi-focal cortically scaled pattern VEP was recorded up to 250 of eccentricity in normal subjects. Monopolar and varying bipolar electrode positions were used. The monopolar response was strongly biased towards the lower hemifield. Bipolar leads straddling the inion (2 cm above and below) achieved approximately equal signals from the upper and lower visual field. Division into sectors of similar wave-form augments the analysis compared with summed full-field responses. With this technique, the multi-focal VEP can be used to objectively assess the visual field.
European journal of human genetics : EJHG, 2014
Developmental eye diseases, including cataract/microcornea, Peters anomaly and coloboma/microphth... more Developmental eye diseases, including cataract/microcornea, Peters anomaly and coloboma/microphthalmia/anophthalmia, are caused by mutations encoding many different signalling and structural proteins in the developing eye. All modes of Mendelian inheritance occur and many are sporadic cases, so provision of accurate recurrence risk information for families and affected individuals is highly challenging. Extreme genetic heterogeneity renders testing for all known disease genes clinically unavailable with traditional methods. We used whole-exome sequencing in 11 unrelated developmental eye disease patients, as it provides a strategy for assessment of multiple disease genes simultaneously. We identified five causative variants in four patients in four different disease genes, GJA8, CRYGC, PAX6 and CYP1B1. This detection rate (36%) is high for a group of patients where clinical testing is frequently not undertaken due to lack of availability and cost. The results affected clinical manag...
Canadian Journal of Ophthalmology / Journal Canadien d'Ophtalmologie, 2014
To describe 2 cases of spontaneous corneal clearing after Descemetorhexis: 1 after iatrogenic tra... more To describe 2 cases of spontaneous corneal clearing after Descemetorhexis: 1 after iatrogenic trauma (Case 1) and 1 as an intentional surgical intervention for Fuchs endothelial dystrophy (Case 2). Retrospective case reports. Full corneal clarity was observed to restore at approximately 1 month after surgery in both cases. Central endothelial cell counts were recorded as 753 and 731 cells/mm(2) in cases 1 and 2, respectively, at last follow-up. Best spectacle corrected visual acuity (BSCVA) at was 6/6 in both cases at 6 weeks and is retained at 9 months. Selective Descemetorhexis may offer visual rehabilitation without the need for a graft in select cases of Fuchs endothelial dystrophy. Descemetopexy in anticipation of corneal clearing is a viable initial strategy in cases of iatrogenic Descemet trauma with detachment.
JAMA Ophthalmology, 2013
Microphthalmia, anophthalmia, and coloboma form an interrelated spectrum of congenital eye abnorm... more Microphthalmia, anophthalmia, and coloboma form an interrelated spectrum of congenital eye abnormalities. To document the ocular and systemic findings and inheritance patterns in patients with microphthalmia, anophthalmia, and coloboma disease to gain insight into the underlying developmental etiologies. This retrospective consecutive case series was conducted at a tertiary referral center. Included in the study were 141 patients with microphthalmia, anophthalmia, and coloboma disease without a recognized syndromic etiology who attended the Westmead Children's Hospital, Sydney, from 1981-2012. Cases were grouped on the basis of the presence or absence of an optic fissure closure defect (OFCD); those with OFCD were further subdivided into microphthalmic and nonmicrophthalmic cases. Anophthalmic cases were considered as a separate group. Associated ocular and systemic abnormalities and inheritance patterns were assessed. Of 141 cases, 61 (43%) were microphthalmic non-OFCD (NOFCD), 34 (24%) microphthalmic OFCD, 32 (23%) nonmicrophthalmic coloboma (OFCD), 9 (6%) anophthalmic, and 5 (4%) were unclassified. Sixty-three (45%) had bilateral disease. Eighty-four patients (60%) had an associated ocular abnormality; of these, cataract (P…
Survey of Ophthalmology, 1999
Journal of the American Society of Nephrology, 2005
The Journal of Pediatrics, 2004
To objectively define criteria for intracranial optic nerve (ON) size in ON hypoplasia (ONH) on m... more To objectively define criteria for intracranial optic nerve (ON) size in ON hypoplasia (ONH) on magnetic resonance imaging (MRI) scans. Intracranial ON sizes from MRI were compared between 46 children with ONH diagnosed by ophthalmoscopy (group 1, isolated ONH, 8 children; and group 2, ONH associated with abnormalities of the hypothalamic-pituitary axis and septum pellucidum, 38 children) and children with multiple pituitary hormone deficiency (group 3, multiple pituitary hormone deficiency, 14 children), isolated growth hormone deficiency (group 4, isolated growth hormone deficiency, 15 children), and idiopathic short stature (group 5, idiopathic short stature, 10 children). Intracranial ON size was determined by the cross-sectional area, calculated as [pi x (1/2) height x (1/2) width]. Groups 1 and 2 had lower intracranial ON size than did groups 3, 4, and 5 (P < .001). No patients in groups 3 through 5 who had MRI after 12 months of age (when 95% adult size of ONs is attained) had ONs <2.9 mm 2 . Visual acuity correlated significantly with ON size (P < .01). Magnetic resonance imaging of the ONs with cross-sectional area <2.9 mm 2 in a short child more than 12 months of age, with or without hypothalamic-pituitary axis abnormalities, confirms the clinical diagnosis of ONH.
Journal of Glaucoma, 2009
The Journal of Clinical Endocrinology & Metabolism, 2003
European Journal of Human Genetics, 2010
European Journal of Human Genetics, 2010
Investigative Ophthalmology & Visual Science, 2007
Clinical & Experimental Ophthalmology, 2012
Glaucoma is a sight-threatening disease affecting 3% of the population over the age of 50. Glau... more Glaucoma is a sight-threatening disease affecting 3% of the population over the age of 50. Glaucoma is treatable, and severe vision loss can usually be prevented if diagnosis is made at an early stage. Genetic factors play a major role in the pathogenesis of the condition, and therefore, genetic testing to identify asymptomatic at-risk individuals is a promising strategy to reduce the prevalence of glaucoma blindness. Furthermore, unravelling genetic risk factors for glaucoma would also allow a better understanding of the pathogenesis of the condition and the development of new treatments. The Australian and New Zealand Registry of Advanced Glaucoma is a prospective study that aims to develop a large cohort of glaucoma cases with severe visual field loss to identify novel genetic risk factors for glaucoma blindness. Clinical information and blood are collected from participants after referral by eye practitioners. Samples are collected across Australia and New Zealand using postage kits. Our registry has recruited just over 2000 participants with advanced glaucoma, as well as secondary and developmental glaucomas. A positive family history of glaucoma is present in more than half of the advanced glaucoma cases and the age at diagnosis is significantly younger for participants with affected relatives, which reinforces the involvement of genetic factors in glaucoma. With the collection of glaucoma cases recruited so far, our registry aims to identify novel glaucoma genetic risk factors to establish risk profiling of the population and protocols for genetic testing.
Twin Research and Human Genetics, 2008
Nutrition reviews, 2015
Age-related macular degeneration (AMD) causes a significant proportion of visual loss in the deve... more Age-related macular degeneration (AMD) causes a significant proportion of visual loss in the developed world. Currently, little is known about its pathogenesis, and treatment options are limited. Dietary intake is one of the few modifiable risk factors for this condition. The best-validated therapies remain oral antioxidant supplements based on those investigated in the Age-Related Eye Disease Study (AREDS) and the recently completed Age-Related Eye Disease Study 2 (AREDS2). In this review, current dietary guidelines related to AMD, along with the underlying evidence to support them, are presented in conjunction with current treatment recommendations. Both AREDS and AREDS2 are discussed, as are avenues for further research, including supplementation with vitamin D and saffron. Despite the considerable disease burden of atrophic AMD, few effective therapies are available to treat it, and further research is required.
BMJ case reports, 2011
Both intracranial hypertension and keratoconus may be associated with visual impairment. The auth... more Both intracranial hypertension and keratoconus may be associated with visual impairment. The authors present a case of a young female with poor right vision that did not improve despite treatment of her intracranial hypertension. Ophthalmic consultation diagnosed keratoconus as the cause.
Australian and New Zealand journal of ophthalmology, 1998
To improve the performance of visual-evoked potentials (VEP) in the assessment of the human visua... more To improve the performance of visual-evoked potentials (VEP) in the assessment of the human visual field, the multi-focal cortically scaled pattern VEP was recorded up to 250 of eccentricity in normal subjects. Monopolar and varying bipolar electrode positions were used. The monopolar response was strongly biased towards the lower hemifield. Bipolar leads straddling the inion (2 cm above and below) achieved approximately equal signals from the upper and lower visual field. Division into sectors of similar wave-form augments the analysis compared with summed full-field responses. With this technique, the multi-focal VEP can be used to objectively assess the visual field.
European journal of human genetics : EJHG, 2014
Developmental eye diseases, including cataract/microcornea, Peters anomaly and coloboma/microphth... more Developmental eye diseases, including cataract/microcornea, Peters anomaly and coloboma/microphthalmia/anophthalmia, are caused by mutations encoding many different signalling and structural proteins in the developing eye. All modes of Mendelian inheritance occur and many are sporadic cases, so provision of accurate recurrence risk information for families and affected individuals is highly challenging. Extreme genetic heterogeneity renders testing for all known disease genes clinically unavailable with traditional methods. We used whole-exome sequencing in 11 unrelated developmental eye disease patients, as it provides a strategy for assessment of multiple disease genes simultaneously. We identified five causative variants in four patients in four different disease genes, GJA8, CRYGC, PAX6 and CYP1B1. This detection rate (36%) is high for a group of patients where clinical testing is frequently not undertaken due to lack of availability and cost. The results affected clinical manag...
Canadian Journal of Ophthalmology / Journal Canadien d'Ophtalmologie, 2014
To describe 2 cases of spontaneous corneal clearing after Descemetorhexis: 1 after iatrogenic tra... more To describe 2 cases of spontaneous corneal clearing after Descemetorhexis: 1 after iatrogenic trauma (Case 1) and 1 as an intentional surgical intervention for Fuchs endothelial dystrophy (Case 2). Retrospective case reports. Full corneal clarity was observed to restore at approximately 1 month after surgery in both cases. Central endothelial cell counts were recorded as 753 and 731 cells/mm(2) in cases 1 and 2, respectively, at last follow-up. Best spectacle corrected visual acuity (BSCVA) at was 6/6 in both cases at 6 weeks and is retained at 9 months. Selective Descemetorhexis may offer visual rehabilitation without the need for a graft in select cases of Fuchs endothelial dystrophy. Descemetopexy in anticipation of corneal clearing is a viable initial strategy in cases of iatrogenic Descemet trauma with detachment.
JAMA Ophthalmology, 2013
Microphthalmia, anophthalmia, and coloboma form an interrelated spectrum of congenital eye abnorm... more Microphthalmia, anophthalmia, and coloboma form an interrelated spectrum of congenital eye abnormalities. To document the ocular and systemic findings and inheritance patterns in patients with microphthalmia, anophthalmia, and coloboma disease to gain insight into the underlying developmental etiologies. This retrospective consecutive case series was conducted at a tertiary referral center. Included in the study were 141 patients with microphthalmia, anophthalmia, and coloboma disease without a recognized syndromic etiology who attended the Westmead Children's Hospital, Sydney, from 1981-2012. Cases were grouped on the basis of the presence or absence of an optic fissure closure defect (OFCD); those with OFCD were further subdivided into microphthalmic and nonmicrophthalmic cases. Anophthalmic cases were considered as a separate group. Associated ocular and systemic abnormalities and inheritance patterns were assessed. Of 141 cases, 61 (43%) were microphthalmic non-OFCD (NOFCD), 34 (24%) microphthalmic OFCD, 32 (23%) nonmicrophthalmic coloboma (OFCD), 9 (6%) anophthalmic, and 5 (4%) were unclassified. Sixty-three (45%) had bilateral disease. Eighty-four patients (60%) had an associated ocular abnormality; of these, cataract (P…
Survey of Ophthalmology, 1999
Journal of the American Society of Nephrology, 2005
The Journal of Pediatrics, 2004
To objectively define criteria for intracranial optic nerve (ON) size in ON hypoplasia (ONH) on m... more To objectively define criteria for intracranial optic nerve (ON) size in ON hypoplasia (ONH) on magnetic resonance imaging (MRI) scans. Intracranial ON sizes from MRI were compared between 46 children with ONH diagnosed by ophthalmoscopy (group 1, isolated ONH, 8 children; and group 2, ONH associated with abnormalities of the hypothalamic-pituitary axis and septum pellucidum, 38 children) and children with multiple pituitary hormone deficiency (group 3, multiple pituitary hormone deficiency, 14 children), isolated growth hormone deficiency (group 4, isolated growth hormone deficiency, 15 children), and idiopathic short stature (group 5, idiopathic short stature, 10 children). Intracranial ON size was determined by the cross-sectional area, calculated as [pi x (1/2) height x (1/2) width]. Groups 1 and 2 had lower intracranial ON size than did groups 3, 4, and 5 (P < .001). No patients in groups 3 through 5 who had MRI after 12 months of age (when 95% adult size of ONs is attained) had ONs <2.9 mm 2 . Visual acuity correlated significantly with ON size (P < .01). Magnetic resonance imaging of the ONs with cross-sectional area <2.9 mm 2 in a short child more than 12 months of age, with or without hypothalamic-pituitary axis abnormalities, confirms the clinical diagnosis of ONH.
Journal of Glaucoma, 2009
The Journal of Clinical Endocrinology & Metabolism, 2003
European Journal of Human Genetics, 2010
European Journal of Human Genetics, 2010