- Email: [email protected]
Retinal vessel diameters and risk of hypertension. The Rotterdam Study
ABSTRACTS EDITED BY HANS E. GROSSNIKLAUS, MD
●
Patients with hemianopic alexia adopt an inefficient eye movement strategy when reading text. McDonald SA, Spitsyna G, Shillcock RC, Wise RJ, Leff AP.* Brain 2006;129:158 –167.
P
ATIENTS WITH AN ACQUIRED HOMONYMOUS HEMI-
anopia often compensate for some of the visual impairment by changes in their eye movement patterns; however, these patients often complain of persistent text reading problems. Using a video-based eye-movement tracking system, the authors evaluated the text reading behavior of patients with long-standing hemianopic alexia (condition affecting left-to-right readers, with a homonymous field defect that encroaches into their right foveal/ parafoveal visual field). Using word-cased analysis of text reading, they compared the patients’ reading scanpaths to those generated by normal controls reading the same passages, and a random model generated by matching the patients’ eye movement data to random permutations of the text they read. They observed that patients adopt an inefficient reading strategy, fixating to the left of the preferred viewing location of words of four letters and longer. Fixating to the left of the normal preferred viewing location not only results in less of the fixated word being processed by the language system; ensuing fixations are also more likely to land within the same word (a refixation). They conclude that this refixation rate is the main factor in slowing reading times in these patients.—Valérie Biousse *A. P. Leff, Department of Clinical Neurosciences, Royal Free Hospital and University College Medical School, London NW32QG UK; e-mail: [email protected]
disease. They studied 490 persons (60 to 90 years of age) without dementia from a population-based cohort study. At baseline (1990 to 1993), retinal arteriolar and venular diameters were measured on digitized images of one eye of each participant. In 1995 and 1996, participants underwent cerebral MRI scanning. The severity of periventricular white matter lesions was rated on a 9-point scale; the total subcortical white matter lesion volume (range: 0 to 29.5 ml) was measured, and the presence of lacunar infarcts also noted. On average 3.3 years later, 279 persons had a second MRI. Changes in periventricular and subcortical white matter lesions were rated with a semi-quantitative scale, and progression was classified as no, minor, and marked. An incident infarct was a new infarct on the follow-up MRI. They observed that neither venular nor arteriolar diameters were related to the severity of cerebral small vessel disease. Larger venular diameters were, however, associated with a marked progression of cerebral small vessel disease. Age and gender adjusted odds ratios (ORs) per standard deviation increase were 1.71 [95% confidence interval (CI): 1.11 to 2.61] for periventricular, 1.72 (95% CI: 1.09 to 2.71) for subcortical white matter lesion progression and 1.59 (95% CI: 1.06 to 2.39) for incident lacunar infarcts. These associations were independent of other cardiovascular risk factors. Only the OR for incident lacunar infarcts was attenuated (1.24; 95% CI: 0.72 to 2.12). No association was observed between arteriolar diameters and progression of cerebral small vessel disease. The authors conclude that only retinal venular dilatation was related to progression of cerebral small vessel disease.—Valérie Biousse *M. M. Breteler, Department of Epidemiology and Biostatistics, Erasmus Medical Center, PO Box 1738, 3000DR, Rotterdam, The Netherlands.
●
Retinal vessel diameters and cerebral small vessel disease: the Rotterdam Scan Study. Ikram MK, De Jong FJ, Van Dijk EJ, Prins ND, Hofman A, Breteler MM,* De Jong PT. Brain 2006;129:182–188.
P
REVIOUS STUDIES HAVE SHOWN THAT PERSONS WITH
smaller retinal arteriolar-to-venular ratio tend to have more white matter lesions on MRI. It is unclear whether this is attributable to arteriolar narrowing or venular dilatation. In this study, the authors investigated whether smaller arteriolar or larger venular diameters, or both, were related to severity and progression of cerebral small vessel 0002-9394/06/$32.00
©
2006 BY
●
Retinal vessel diameters and risk of hypertension. The Rotterdam Study. Ikram MK, Witteman JC, Vingerling JR, Breteler MM, Hofman A, De Jong PT.* Hypertension 2006;47:1– 6.
I
T IS WELL KNOWN THAT GENERALIZED RETINAL ARTERIO-
lar narrowing is an important sign of systemic hypertension, and previous studies have shown that lower arteriolar:venular diameter ratio predicts the risk of hypertension. The authors evaluated whether this association is based on arteriolar or
ELSEVIER INC. ALL
RIGHTS RESERVED.
601
venular diameters, or both. This study was based on the prospective population-based Rotterdam Study (1990 to 1993) and included 1900 participants (ⱖ55 years of age) of whom 739 persons had normal blood pressure (systolic ⬍120 mm Hg and diastolic ⬍80 mm Hg) and 1161 prehypertension (systolic 120 to 139 mm Hg or diastolic 80 to 89 mm Hg). For each participant, retinal arteriolar and venular diameters were measured on digitized images of one eye. After a mean follow-up of 6.6 years, 808 persons developed hypertension, defined as either systolic blood pressure ⬎140 mm Hg or diastolic blood pressure ⬎90 mm Hg or use of antihypertensive medication. Adjusted for age, gender, follow-up time, body mass index, smoking, diabetes mellitus, total and high-density lipoprotein cholesterol, C-reactive protein, and intima-media thickness, arteriolar narrowing was associated with an increased risk of hypertension (odds ratio per SD: 1.38; 95% CI, 1.23 to 1.55); for venular narrowing this was less striking (OR: 1.17; 95% CI, 1.04 to 1.32). Each SD decrease in the arteriolar: venular diameter ratio significantly increased the risk of hypertension by 24%. To examine the effect of baseline blood pressure, participants were stratified into those with “normal blood pressure” or “prehypertension.” Within each group, arteriolar narrowing was still related to incident hypertension. The authors conclude that both retinal arteriolar and venular narrowing may precede the development of systemic hypertension.—Valérie Biousse
The treated group had a higher proportion of neurological and visual complications than people who were not treated (2(2). ⫽ 25.26, P ⫽ .0003). The authors concluded that endovascular treatment of carotid cavernous aneurysms lead to higher rate of pain resolution compared with untreated patients, even after adjusting for initial pain severity. Diplopia may not resolve after treatment. The authors conclude that treatment should be considered only in cases of debilitating pain, visual loss from compressive optic neuropathy, diplopia in primary gaze, or in patients with risk factors for major complications such as preexisting coagulopathy or sphenoid sinus erosion.—Valérie Biousse *Hadas Stiebel-Kalish, MD, Neuro-Ophthalmology Service, Department of Ophthalmology, Rabin Medical Center, Petah Tikva 49100, Israel; e-mail: [email protected]
●
Possible sources of neuroprotection following subretinal silicon chip implantation in RCS rats. Pardue MT,* Phillips MJ, Yin H, Fernandes A, Cheng Y, Chow AY, Ball SL. J Neural Eng 2005;2:S39 –S47.
R
stimulate existing neural circuits in diseased retinas in order to create a visual signal. Implantation of retinal prosthetics may create a neurotrophic environment that also leads to improvements in visual function. Possible sources of increased neuroprotective effects on the retina may arise from electrical activity generated by the prosthetic, mechanical injury attributable to surgical implantation, and/or presence of a chronic foreign body. In this study, three neuroprotective sources were evaluated by implanting Royal College of Surgeons (RCS) rates, a model of retinitis pigmentosa, with a subretinal implant at an early stage of photoreceptor degeneration. Treatment groups included rats implanted with active and inactive devices and sham-operated rats. These groups were compared with unoperated controls. Evaluation of retinal function throughout an 18-week post-implantation period demonstrated transient functional improvements in eyes implanted with an inactive device at 6, 12, and 14 weeks post-implantation. However, the number of photoreceptors located directly over or around the implant or sham incision was considerably increased in eyes implanted with an active or inactive device or sham-operated. These results indicate that in the RCS rat , localized neuroprotection of photoreceptors from mechanical injury or a chronic foreign body may provide similar results to subretinal electrical stimulation at the current output evaluated.—Hans E. Grossniklaus
*Paulus T. V. M. De Jong, The Netherlands Ophthalmic Research Institute, KNAW, Meibergdreef 47, 1105 BA Amsterdam, The Netherlands; e-mail: [email protected]
●
Presentation, natural history, and management of carotid cavernous aneurysms. Stiebel-Kalish H,* Kalish Y, Bar-On RH, Setton A, Niimi Y, Berenstein A, Kupersmith MJ. Neurosurgery 2005;57:850 – 857.
T
HIS STUDY PRESENTS THE NEURO-OPHTHALMIC CHAR-
acteristics of a large cohort of carotid cavernous aneurysms (CCA). The authors retrospectively reviewed 185 patients with 206 CCAs examined between 1980 and 2001. Patients’ symptoms and findings at presentation and after treatment were recorded. The effect of treatment on outcome and on complication rate was analyzed using the chi test, multivariate analysis of covariance, model-selection log-linear analysis, and multinomial logistic regression. Long-term follow-up was available for 189 of 206 CCAs. Seventy-four CCAs underwent treatment (endovascular, 67 [91%]; surgical treatment, six [9%]), and 115 were followed for an average of 4 years, two of which required later treatment. Treatment reduced the incidence and severity of pain, even after adjusting for the severity of initial pain (F(1,192 ⫽ 9.59, P ⫽ .002). Treatment did not significantly affect the patient’s final diplopia after adjusting for their initial diplopia (F(1,182 ⫽ 2.01, P ⫽ .158). 602
AMERICAN JOURNAL
ETINAL PROSTHETIC IMPLANTS ARE DESIGNED TO
*M. T. Pardue, Atlanta VA Medical Center, Research Service (151 Oph), 1670 Clairmont Road, Decatur, GA 300033. OF
OPHTHALMOLOGY
MARCH 2006
●
Patients with hemianopic alexia adopt an inefficient eye movement strategy when reading text. McDonald SA, Spitsyna G, Shillcock RC, Wise RJ, Leff AP.* Brain 2006;129:158 –167.
P
ATIENTS WITH AN ACQUIRED HOMONYMOUS HEMI-
anopia often compensate for some of the visual impairment by changes in their eye movement patterns; however, these patients often complain of persistent text reading problems. Using a video-based eye-movement tracking system, the authors evaluated the text reading behavior of patients with long-standing hemianopic alexia (condition affecting left-to-right readers, with a homonymous field defect that encroaches into their right foveal/ parafoveal visual field). Using word-cased analysis of text reading, they compared the patients’ reading scanpaths to those generated by normal controls reading the same passages, and a random model generated by matching the patients’ eye movement data to random permutations of the text they read. They observed that patients adopt an inefficient reading strategy, fixating to the left of the preferred viewing location of words of four letters and longer. Fixating to the left of the normal preferred viewing location not only results in less of the fixated word being processed by the language system; ensuing fixations are also more likely to land within the same word (a refixation). They conclude that this refixation rate is the main factor in slowing reading times in these patients.—Valérie Biousse *A. P. Leff, Department of Clinical Neurosciences, Royal Free Hospital and University College Medical School, London NW32QG UK; e-mail: [email protected]
disease. They studied 490 persons (60 to 90 years of age) without dementia from a population-based cohort study. At baseline (1990 to 1993), retinal arteriolar and venular diameters were measured on digitized images of one eye of each participant. In 1995 and 1996, participants underwent cerebral MRI scanning. The severity of periventricular white matter lesions was rated on a 9-point scale; the total subcortical white matter lesion volume (range: 0 to 29.5 ml) was measured, and the presence of lacunar infarcts also noted. On average 3.3 years later, 279 persons had a second MRI. Changes in periventricular and subcortical white matter lesions were rated with a semi-quantitative scale, and progression was classified as no, minor, and marked. An incident infarct was a new infarct on the follow-up MRI. They observed that neither venular nor arteriolar diameters were related to the severity of cerebral small vessel disease. Larger venular diameters were, however, associated with a marked progression of cerebral small vessel disease. Age and gender adjusted odds ratios (ORs) per standard deviation increase were 1.71 [95% confidence interval (CI): 1.11 to 2.61] for periventricular, 1.72 (95% CI: 1.09 to 2.71) for subcortical white matter lesion progression and 1.59 (95% CI: 1.06 to 2.39) for incident lacunar infarcts. These associations were independent of other cardiovascular risk factors. Only the OR for incident lacunar infarcts was attenuated (1.24; 95% CI: 0.72 to 2.12). No association was observed between arteriolar diameters and progression of cerebral small vessel disease. The authors conclude that only retinal venular dilatation was related to progression of cerebral small vessel disease.—Valérie Biousse *M. M. Breteler, Department of Epidemiology and Biostatistics, Erasmus Medical Center, PO Box 1738, 3000DR, Rotterdam, The Netherlands.
●
Retinal vessel diameters and cerebral small vessel disease: the Rotterdam Scan Study. Ikram MK, De Jong FJ, Van Dijk EJ, Prins ND, Hofman A, Breteler MM,* De Jong PT. Brain 2006;129:182–188.
P
REVIOUS STUDIES HAVE SHOWN THAT PERSONS WITH
smaller retinal arteriolar-to-venular ratio tend to have more white matter lesions on MRI. It is unclear whether this is attributable to arteriolar narrowing or venular dilatation. In this study, the authors investigated whether smaller arteriolar or larger venular diameters, or both, were related to severity and progression of cerebral small vessel 0002-9394/06/$32.00
©
2006 BY
●
Retinal vessel diameters and risk of hypertension. The Rotterdam Study. Ikram MK, Witteman JC, Vingerling JR, Breteler MM, Hofman A, De Jong PT.* Hypertension 2006;47:1– 6.
I
T IS WELL KNOWN THAT GENERALIZED RETINAL ARTERIO-
lar narrowing is an important sign of systemic hypertension, and previous studies have shown that lower arteriolar:venular diameter ratio predicts the risk of hypertension. The authors evaluated whether this association is based on arteriolar or
ELSEVIER INC. ALL
RIGHTS RESERVED.
601
venular diameters, or both. This study was based on the prospective population-based Rotterdam Study (1990 to 1993) and included 1900 participants (ⱖ55 years of age) of whom 739 persons had normal blood pressure (systolic ⬍120 mm Hg and diastolic ⬍80 mm Hg) and 1161 prehypertension (systolic 120 to 139 mm Hg or diastolic 80 to 89 mm Hg). For each participant, retinal arteriolar and venular diameters were measured on digitized images of one eye. After a mean follow-up of 6.6 years, 808 persons developed hypertension, defined as either systolic blood pressure ⬎140 mm Hg or diastolic blood pressure ⬎90 mm Hg or use of antihypertensive medication. Adjusted for age, gender, follow-up time, body mass index, smoking, diabetes mellitus, total and high-density lipoprotein cholesterol, C-reactive protein, and intima-media thickness, arteriolar narrowing was associated with an increased risk of hypertension (odds ratio per SD: 1.38; 95% CI, 1.23 to 1.55); for venular narrowing this was less striking (OR: 1.17; 95% CI, 1.04 to 1.32). Each SD decrease in the arteriolar: venular diameter ratio significantly increased the risk of hypertension by 24%. To examine the effect of baseline blood pressure, participants were stratified into those with “normal blood pressure” or “prehypertension.” Within each group, arteriolar narrowing was still related to incident hypertension. The authors conclude that both retinal arteriolar and venular narrowing may precede the development of systemic hypertension.—Valérie Biousse
The treated group had a higher proportion of neurological and visual complications than people who were not treated (2(2). ⫽ 25.26, P ⫽ .0003). The authors concluded that endovascular treatment of carotid cavernous aneurysms lead to higher rate of pain resolution compared with untreated patients, even after adjusting for initial pain severity. Diplopia may not resolve after treatment. The authors conclude that treatment should be considered only in cases of debilitating pain, visual loss from compressive optic neuropathy, diplopia in primary gaze, or in patients with risk factors for major complications such as preexisting coagulopathy or sphenoid sinus erosion.—Valérie Biousse *Hadas Stiebel-Kalish, MD, Neuro-Ophthalmology Service, Department of Ophthalmology, Rabin Medical Center, Petah Tikva 49100, Israel; e-mail: [email protected]
●
Possible sources of neuroprotection following subretinal silicon chip implantation in RCS rats. Pardue MT,* Phillips MJ, Yin H, Fernandes A, Cheng Y, Chow AY, Ball SL. J Neural Eng 2005;2:S39 –S47.
R
stimulate existing neural circuits in diseased retinas in order to create a visual signal. Implantation of retinal prosthetics may create a neurotrophic environment that also leads to improvements in visual function. Possible sources of increased neuroprotective effects on the retina may arise from electrical activity generated by the prosthetic, mechanical injury attributable to surgical implantation, and/or presence of a chronic foreign body. In this study, three neuroprotective sources were evaluated by implanting Royal College of Surgeons (RCS) rates, a model of retinitis pigmentosa, with a subretinal implant at an early stage of photoreceptor degeneration. Treatment groups included rats implanted with active and inactive devices and sham-operated rats. These groups were compared with unoperated controls. Evaluation of retinal function throughout an 18-week post-implantation period demonstrated transient functional improvements in eyes implanted with an inactive device at 6, 12, and 14 weeks post-implantation. However, the number of photoreceptors located directly over or around the implant or sham incision was considerably increased in eyes implanted with an active or inactive device or sham-operated. These results indicate that in the RCS rat , localized neuroprotection of photoreceptors from mechanical injury or a chronic foreign body may provide similar results to subretinal electrical stimulation at the current output evaluated.—Hans E. Grossniklaus
*Paulus T. V. M. De Jong, The Netherlands Ophthalmic Research Institute, KNAW, Meibergdreef 47, 1105 BA Amsterdam, The Netherlands; e-mail: [email protected]
●
Presentation, natural history, and management of carotid cavernous aneurysms. Stiebel-Kalish H,* Kalish Y, Bar-On RH, Setton A, Niimi Y, Berenstein A, Kupersmith MJ. Neurosurgery 2005;57:850 – 857.
T
HIS STUDY PRESENTS THE NEURO-OPHTHALMIC CHAR-
acteristics of a large cohort of carotid cavernous aneurysms (CCA). The authors retrospectively reviewed 185 patients with 206 CCAs examined between 1980 and 2001. Patients’ symptoms and findings at presentation and after treatment were recorded. The effect of treatment on outcome and on complication rate was analyzed using the chi test, multivariate analysis of covariance, model-selection log-linear analysis, and multinomial logistic regression. Long-term follow-up was available for 189 of 206 CCAs. Seventy-four CCAs underwent treatment (endovascular, 67 [91%]; surgical treatment, six [9%]), and 115 were followed for an average of 4 years, two of which required later treatment. Treatment reduced the incidence and severity of pain, even after adjusting for the severity of initial pain (F(1,192 ⫽ 9.59, P ⫽ .002). Treatment did not significantly affect the patient’s final diplopia after adjusting for their initial diplopia (F(1,182 ⫽ 2.01, P ⫽ .158). 602
AMERICAN JOURNAL
ETINAL PROSTHETIC IMPLANTS ARE DESIGNED TO
*M. T. Pardue, Atlanta VA Medical Center, Research Service (151 Oph), 1670 Clairmont Road, Decatur, GA 300033. OF
OPHTHALMOLOGY
MARCH 2006