Problem With Vision BlindnessNCT00450294
Intraocular Pressure During Abdominal Aortic Aneurysm (AAA) Repair
An observational study of Problem With Vision Blindness and Intraocular Pressure, run by University of Manitoba at 1 site in Canada.
Trial summary
The objective of this study will be to answer a clinical question that has not already been investigated; that is, what are the effects of aortic infra-renal clamping and unclamping on intraocular pressure during Abdominal Aortic Aneurysm (AAA) repair? Depending on the results, this study may raise or alleviate… Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- Problem With Vision Blindness, Intraocular Pressure, Ischemic Optic Neuropathy
- How many people
- 10 participants
- Where
- 1 siteCanada
- Study dates
- Mar 2007to Aug 2007
- Phase
- Observational
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Study population: All patients with known infrarenal abdominal aortic aneurysm for open repair will be screened through the preadmission anesthetic clinic. If they do not meet exclusion criteria and have signed informed consent for the the study, they will be enrolled to assess for changes in intraocular pressure during open abdominal aortic aneurysm repair.
Who may be able to join
- All patients presenting to St. Boniface General Hospital for elective AAA repair requiring an arterial line, central line and general anesthesia will be eligible for inclusion in this study.
Who cannot join
- . The exclusion criteria for this study are:
- Patients with a history of acute or chronic eye disease
- Allergy to topical ophthalmologic anesthesia
- Patients receiving nitrous oxide, ketamine or succinylcholine during anesthesia
- If the surgical procedure will require the aorta to be re-clamped following unclamping, those patients will also be excluded
- Patients that are VRE+ or MRSA+ will be excluded for infection control purposes
Trial locations and contacts
1 site in 1 country.
About this study
Official title: The Effect of Aortic Infrarenal Clamping and Unclamping On Intraocular Pressure During Abdominal Aortic Aneurysm (AAA) Repair
The objective of this study will be to answer a clinical question that has not already been investigated; that is, what are the effects of aortic infra-renal clamping and unclamping on intraocular pressure during Abdominal Aortic Aneurysm (AAA) repair? Depending on the results, this study may raise or alleviate concern that vascular surgery for abdominal aortic aneurysm could contribute to early perioperative exacerbation of pre-existing eye disease and increase a patient's vulnerability to developing a type of blindness known as ischemic optic neuropathy. The purpose of this observational study is to evaluate whether intraocular pressure measurements with a handheld tonometer will detect changes in intraocular pressure related to intraoperative events during aortic cross clamping and unclamping that may provide information on causes of perioperative blindness.
Read the detailed description
Perioperative blindness in nonocular surgery has gained significant clinical interest as an overwhelming complication with an increasing incidence. Initial published studies suggested a rare occurrence with an estimated postoperative visual loss of 0.002% and 0.0008% (1,2). However, retrospective reviews in spinal and cardiac surgery demonstrated higher rates of perioperative blindness; that is, between 0.2% and 0.06% respectively (3,4). The difference in published reports suggests that the true incidence is likely underestimated because of fears regarding litigation, ineffective means of reporting and extra work involved. Fortunately, numerous case reports and series in the middle to late 1990s were published; prompting the American Society of Anesthesiologists (ASA) Committee on Professional Liability to establish the ASA Postoperative Visual Loss Registry (POVL) in 1999 as a medium to collect confidential, comprehensive perioperative data on patients developing postoperative blindness.
The POVL registry, along with other case series, has demonstrated that the most common cause of visual loss is non-arteritic ischemic optic neuropathy (5,6,7). Perioperative non-arteritic ischemic optic neuropathy (ION) is a consequence of patient and surgery specific factors that results from hypoperfusion and infarction of the optic nerve head (8). Anatomical factors such as variation in the number of short posterior ciliary arteries (sPCA) supplying the optic nerve head, location of sPCA watershed zone, and small optic cup to disk ratio increase susceptibility to optic nerve ischemia (8,9). Surgery specific factors involve profound blood loss, anemia, hypotension, prone positioning and duration of surgery (5,6,7,10). The interaction of these surgical variables and patient specific anatomical factors can decrease ocular perfusion pressure (the difference between mean arterial pressure and intraocular pressure) and result in ION (11).
Based on the determinants of ocular perfusion pressure (OPP), low mean arterial pressure (MAP) and/or high intraocular pressure (IOP) can decrease OPP and lead to ION. Therefore, it is necessary to investigate changes in IOP incurred from different types of surgery that may increase vulnerability to developing ION. Normal IOP is between 12 - 20 mm Hg. Studies have been published assessing intraocular changes with prone positioning, laparoscopic surgery and cardiopulmonary bypass (12,13,14). However, there has been no literature evaluating intraocular pressure during abdominal aortic aneurysm (AAA) repair. AAA repair is a high-risk surgery associated with blood loss, hypotension and has been reported in a case series associated with ION (6). The surgery involves clamping and unclamping of the aorta to facilitate excision of the aneurysm and graft repair. Aortic cross clamping and unclamping is an intense physiologic insult affecting venous return, systemic vascular resistance, cardiac output, and acid base status. These physiologic changes are further pronounced with more proximal cross-clamping and longer duration. Because infrarenal abdominal aortic aneurysms are the most common type of AAA repair, we will be assessing IOP with patients undergoing elective infrarenal abdominal aortic reconstruction.
Infrarenal aortic cross clamping is associated with increases in venous return, central venous pressure and arterial blood pressure (15). The hemodynamic changes with infrarenal unclamping entail decreases in venous return, central venous pressure and arterial blood pressure (15). The determinants of intraocular pressure involve extraocular muscle tone, aqueous flow, choroidal blood volume and central venous pressure (16). The volume redistribution proximal to the aortic cross-clamp should cause a rise in venous pressure, increase resistance to aqueous drainage and increase choroidal blood volume thereby increasing intraocular pressure. However, after aortic unclamping, choroidal blood volume and IOP should decrease as venous return and central venous pressure decline. Therefore, our hypothesis is that IOP will be increased during aortic cross clamping and decreased following aortic unclamping.
- Medical subject headings
- Optic Neuropathy, Ischemic
What is being measured
The primary outcome is the main question the study is designed to answer.
Right Intraocular Pressure During Various Event Intervals in Open Abdominal Aortic Aneurysm Surgery.
Intraocular pressure measurements were made with a tonometer. These measurements were recorded and kept blinded from the clinicians.
Measured: Measurements made at baseline, post induction preincision, 1 min post clamp, 5 min post clamp, 1 min pre unclamp, 1 min post unclamp, 5 min post unclamp, skin closure
Left Intraocular Pressure
Intraocular pressure measurements were made with a tonometer. These measurements were recorded and kept blinded from the clinicians.
Measured: Measurements made at baseline, post induction preincision, 1 min post clamp, 5 min post clamp, 1 min pre unclamp, 1 min post unclamp, 5 min post unclamp, skin closure
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted22 Mar 2007 (estimated)
- Study startMar 2007
- Study completionAug 2007
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Publications (16)Papers the sponsor has linked to this study.
- Other trials for Problem With Vision BlindnessStudies of the same condition, open and under way.
- More trials run by University of ManitobaThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Time perspective
- Prospective
- Enrolment
- 10 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of Manitoba
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Amit Chopra, University of Manitoba
- Investigators
- Amit Chopra, M.D., Principal investigator, University of Manitoba, Department Of Anesthesiology, Faculty of Medicine
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT00450294
- Sponsor's protocol ID
- B2006:180
- Status last verified
- Feb 2014
- First submitted
- 21 Mar 2007
- Last updated
- 31 Mar 2014
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- Yes
Publications
Roth S, Thisted RA, Erickson JP, Black S, Schreider BD. Eye injuries after nonocular surgery. A study of 60,965 anesthetics from 1988 to 1992. Anesthesiology. 1996 Nov;85(5):1020-7. doi: 10.1097/00000542-199611000-00009.
PubMed 8916818Warner ME, Warner MA, Garrity JA, MacKenzie RA, Warner DO. The frequency of perioperative vision loss. Anesth Analg. 2001 Dec;93(6):1417-21, table of contents. doi: 10.1097/00000539-200112000-00013.
PubMed 11726416Stevens WR, Glazer PA, Kelley SD, Lietman TM, Bradford DS. Ophthalmic complications after spinal surgery. Spine (Phila Pa 1976). 1997 Jun 15;22(12):1319-24. doi: 10.1097/00007632-199706150-00008.
PubMed 9201834Nuttall GA, Garrity JA, Dearani JA, Abel MD, Schroeder DR, Mullany CJ. Risk factors for ischemic optic neuropathy after cardiopulmonary bypass: a matched case/control study. Anesth Analg. 2001 Dec;93(6):1410-6, table of contents. doi: 10.1097/00000539-200112000-00012.
PubMed 11726415Lee LA, Roth S, Posner KL, Cheney FW, Caplan RA, Newman NJ, Domino KB. The American Society of Anesthesiologists Postoperative Visual Loss Registry: analysis of 93 spine surgery cases with postoperative visual loss. Anesthesiology. 2006 Oct;105(4):652-9; quiz 867-8. doi: 10.1097/00000542-200610000-00007.
PubMed 17006060Brown RH, Schauble JF, Miller NR. Anemia and hypotension as contributors to perioperative loss of vision. Anesthesiology. 1994 Jan;80(1):222-6. doi: 10.1097/00000542-199401000-00033. No abstract available.
PubMed 8291715Myers MA, Hamilton SR, Bogosian AJ, Smith CH, Wagner TA. Visual loss as a complication of spine surgery. A review of 37 cases. Spine (Phila Pa 1976). 1997 Jun 15;22(12):1325-9. doi: 10.1097/00007632-199706150-00009.
PubMed 9201835Hayreh SS, Jonas JB. Optic disc morphology after arteritic anterior ischemic optic neuropathy. Ophthalmology. 2001 Sep;108(9):1586-94. doi: 10.1016/s0161-6420(01)00649-2.
PubMed 11535455Beck RW, Servais GE, Hayreh SS. Anterior ischemic optic neuropathy. IX. Cup-to-disc ratio and its role in pathogenesis. Ophthalmology. 1987 Nov;94(11):1503-8.
PubMed 3684223Williams EL, Hart WM Jr, Tempelhoff R. Postoperative ischemic optic neuropathy. Anesth Analg. 1995 May;80(5):1018-29. doi: 10.1097/00000539-199505000-00029. No abstract available.
PubMed 7726399Hayreh SS. Anterior ischemic optic neuropathy. Clin Neurosci. 1997;4(5):251-63.
PubMed 9292252Cheng MA, Todorov A, Tempelhoff R, McHugh T, Crowder CM, Lauryssen C. The effect of prone positioning on intraocular pressure in anesthetized patients. Anesthesiology. 2001 Dec;95(6):1351-5. doi: 10.1097/00000542-200112000-00012.
PubMed 1174839113 Kayacan N, Gulbin A, Akar M, Karsli B. The effect of pneumoperitoneum and head-down position on intraocular pressure. Gynaecological Endoscopy 2002;11:383-87.
Larkin DF, Connolly P, Magner JB, Wood AE, Eustace P. Intraocular pressure during cardiopulmonary bypass. Br J Ophthalmol. 1987 Mar;71(3):177-80. doi: 10.1136/bjo.71.3.177.
PubMed 3828271Gelman S. The pathophysiology of aortic cross-clamping and unclamping. Anesthesiology. 1995 Apr;82(4):1026-60. doi: 10.1097/00000542-199504000-00027. No abstract available.
PubMed 7717537
Study at a glance
From the registry record, last updated by the sponsor on 31 Mar 2014. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Effect of Aortic Infrarenal Clamping and Unclamping On Intraocular Pressure During Abdominal Aortic Aneurysm (AAA) Repair
- ClinicalTrials.gov ID
- NCT00450294
- Acronym / sponsor ID
- B2006:180
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 10 participants (actual)
- Lead sponsor
- University of ManitobaUniversity, hospital or other
- Study start
- Mar 2007
- Study completion
- Aug 2007 (actual)
- First posted
- 22 Mar 2007 (estimated)
- Results
- Posted 31 Mar 2014
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The objective of this study will be to answer a clinical question that has not already been investigated; that is, what are the effects of aortic infra-renal clamping and unclamping on intraocular pressure during Abdominal Aortic Aneurysm (AAA) repair? Depending on the results, this study may raise or alleviate concern that vascular surgery for abdominal aortic aneurysm could contribute to early perioperative exacerbation of pre-existing eye disease and increase a patient's vulnerability to developing a type of blindness known as ischemic optic neuropathy. The purpose of this observational study is to evaluate whether intraocular pressure measurements with a handheld tonometer will detect changes in intraocular pressure related to intraoperative events during aortic cross clamping and unclamping that may provide information on causes of perioperative blindness.
Detailed description
Perioperative blindness in nonocular surgery has gained significant clinical interest as an overwhelming complication with an increasing incidence. Initial published studies suggested a rare occurrence with an estimated postoperative visual loss of 0.002% and 0.0008% (1,2). However, retrospective reviews in spinal and cardiac surgery demonstrated higher rates of perioperative blindness; that is, between 0.2% and 0.06% respectively (3,4). The difference in published reports suggests that the true incidence is likely underestimated because of fears regarding litigation, ineffective means of reporting and extra work involved. Fortunately, numerous case reports and series in the middle to late 1990s were published; prompting the American Society of Anesthesiologists (ASA) Committee on Professional Liability to establish the ASA Postoperative Visual Loss Registry (POVL) in 1999 as a medium to collect confidential, comprehensive perioperative data on patients developing postoperative blindness.
The POVL registry, along with other case series, has demonstrated that the most common cause of visual loss is non-arteritic ischemic optic neuropathy (5,6,7). Perioperative non-arteritic ischemic optic neuropathy (ION) is a consequence of patient and surgery specific factors that results from hypoperfusion and infarction of the optic nerve head (8). Anatomical factors such as variation in the number of short posterior ciliary arteries (sPCA) supplying the optic nerve head, location of sPCA watershed zone, and small optic cup to disk ratio increase susceptibility to optic nerve ischemia (8,9). Surgery specific factors involve profound blood loss, anemia, hypotension, prone positioning and duration of surgery (5,6,7,10). The interaction of these surgical variables and patient specific anatomical factors can decrease ocular perfusion pressure (the difference between mean arterial pressure and intraocular pressure) and result in ION (11).
Based on the determinants of ocular perfusion pressure (OPP), low mean arterial pressure (MAP) and/or high intraocular pressure (IOP) can decrease OPP and lead to ION. Therefore, it is necessary to investigate changes in IOP incurred from different types of surgery that may increase vulnerability to developing ION. Normal IOP is between 12 - 20 mm Hg. Studies have been published assessing intraocular changes with prone positioning, laparoscopic surgery and cardiopulmonary bypass (12,13,14). However, there has been no literature evaluating intraocular pressure during abdominal aortic aneurysm (AAA) repair. AAA repair is a high-risk surgery associated with blood loss, hypotension and has been reported in a case series associated with ION (6). The surgery involves clamping and unclamping of the aorta to facilitate excision of the aneurysm and graft repair. Aortic cross clamping and unclamping is an intense physiologic insult affecting venous return, systemic vascular resistance, cardiac output, and acid base status. These physiologic changes are further pronounced with more proximal cross-clamping and longer duration. Because infrarenal abdominal aortic aneurysms are the most common type of AAA repair, we will be assessing IOP with patients undergoing elective infrarenal abdominal aortic reconstruction.
Infrarenal aortic cross clamping is associated with increases in venous return, central venous pressure and arterial blood pressure (15). The hemodynamic changes with infrarenal unclamping entail decreases in venous return, central venous pressure and arterial blood pressure (15). The determinants of intraocular pressure involve extraocular muscle tone, aqueous flow, choroidal blood volume and central venous pressure (16). The volume redistribution proximal to the aortic cross-clamp should cause a rise in venous pressure, increase resistance to aqueous drainage and increase choroidal blood volume thereby increasing intraocular pressure. However, after aortic unclamping, choroidal blood volume and IOP should decrease as venous return and central venous pressure decline. Therefore, our hypothesis is that IOP will be increased during aortic cross clamping and decreased following aortic unclamping.
Study design
- Time perspective
- Prospective
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
- Study population
- All patients with known infrarenal abdominal aortic aneurysm for open repair will be screened through the preadmission anesthetic clinic. If they do not meet exclusion criteria and have signed informed consent for the the study, they will be enrolled to assess for changes in intraocular pressure during open abdominal aortic aneurysm repair.
Key inclusion criteria (1 listed)
- All patients presenting to St. Boniface General Hospital for elective AAA repair requiring an arterial line, central line and general anesthesia will be eligible for inclusion in this study.
Key exclusion criteria (6 listed)
- . The exclusion criteria for this study are:
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Right Intraocular Pressure During Various Event Intervals in Open Abdominal Aortic Aneurysm Surgery.
Time frame: Measurements made at baseline, post induction preincision, 1 min post clamp, 5 min post clamp, 1 min pre unclamp, 1 min post unclamp, 5 min post unclamp, skin closure
Intraocular pressure measurements were made with a tonometer. These measurements were recorded and kept blinded from the clinicians.
Left Intraocular Pressure
Time frame: Measurements made at baseline, post induction preincision, 1 min post clamp, 5 min post clamp, 1 min pre unclamp, 1 min post unclamp, 5 min post unclamp, skin closure
Intraocular pressure measurements were made with a tonometer. These measurements were recorded and kept blinded from the clinicians.
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 31 Mar 2014.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Background: PubMed 8916818Roth S, Thisted RA, Erickson JP, Black S, Schreider BD. Eye injuries after nonocular surgery. A study of 60,965 anesthetics from 1988 to 1992. Anesthesiology. 1996 Nov;85(5):1020-7. doi: 10.1097/00000542-199611000-00009.
- Background: PubMed 11726416Warner ME, Warner MA, Garrity JA, MacKenzie RA, Warner DO. The frequency of perioperative vision loss. Anesth Analg. 2001 Dec;93(6):1417-21, table of contents. doi: 10.1097/00000539-200112000-00013.
- Background: PubMed 9201834Stevens WR, Glazer PA, Kelley SD, Lietman TM, Bradford DS. Ophthalmic complications after spinal surgery. Spine (Phila Pa 1976). 1997 Jun 15;22(12):1319-24. doi: 10.1097/00007632-199706150-00008.
- Background: PubMed 11726415Nuttall GA, Garrity JA, Dearani JA, Abel MD, Schroeder DR, Mullany CJ. Risk factors for ischemic optic neuropathy after cardiopulmonary bypass: a matched case/control study. Anesth Analg. 2001 Dec;93(6):1410-6, table of contents. doi: 10.1097/00000539-200112000-00012.
- Background: PubMed 17006060Lee LA, Roth S, Posner KL, Cheney FW, Caplan RA, Newman NJ, Domino KB. The American Society of Anesthesiologists Postoperative Visual Loss Registry: analysis of 93 spine surgery cases with postoperative visual loss. Anesthesiology. 2006 Oct;105(4):652-9; quiz 867-8. doi: 10.1097/00000542-200610000-00007.
- Background: PubMed 8291715Brown RH, Schauble JF, Miller NR. Anemia and hypotension as contributors to perioperative loss of vision. Anesthesiology. 1994 Jan;80(1):222-6. doi: 10.1097/00000542-199401000-00033. No abstract available.
- Background: PubMed 9201835Myers MA, Hamilton SR, Bogosian AJ, Smith CH, Wagner TA. Visual loss as a complication of spine surgery. A review of 37 cases. Spine (Phila Pa 1976). 1997 Jun 15;22(12):1325-9. doi: 10.1097/00007632-199706150-00009.
- Background: PubMed 11535455Hayreh SS, Jonas JB. Optic disc morphology after arteritic anterior ischemic optic neuropathy. Ophthalmology. 2001 Sep;108(9):1586-94. doi: 10.1016/s0161-6420(01)00649-2.
- Background: PubMed 3684223Beck RW, Servais GE, Hayreh SS. Anterior ischemic optic neuropathy. IX. Cup-to-disc ratio and its role in pathogenesis. Ophthalmology. 1987 Nov;94(11):1503-8.
- Background: PubMed 7726399Williams EL, Hart WM Jr, Tempelhoff R. Postoperative ischemic optic neuropathy. Anesth Analg. 1995 May;80(5):1018-29. doi: 10.1097/00000539-199505000-00029. No abstract available.
- Background: PubMed 9292252Hayreh SS. Anterior ischemic optic neuropathy. Clin Neurosci. 1997;4(5):251-63.
- Background: PubMed 11748391Cheng MA, Todorov A, Tempelhoff R, McHugh T, Crowder CM, Lauryssen C. The effect of prone positioning on intraocular pressure in anesthetized patients. Anesthesiology. 2001 Dec;95(6):1351-5. doi: 10.1097/00000542-200112000-00012.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Amit Chopra, M.D. principal investigator
University of Manitoba, Department Of Anesthesiology, Faculty of Medicine
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Problem With Vision Blindness and Intraocular Pressure, run by University of Manitoba at 1 site in Canada.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 1 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 31 Mar 2014. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Canada. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
Yes. Results are posted in the registry (first posted 31 Mar 2014). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Right Intraocular Pressure During Various Event Intervals in Open Abdominal Aortic Aneurysm Surgery. (time frame: Measurements made at baseline, post induction preincision, 1 min post clamp, 5 min post clamp, 1 min pre unclamp, 1 min post unclamp, 5 min post unclamp, skin closure). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT00450294, which also lists 16 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 31 Mar 2014.