HIV peripheral neuropathy-related degeneration of white matter tracts to sensorimotor cortex.

Human immunodeficiency virus-associated distal sensory polyneuropathy (HIV-DSP) affects up to 50% of people with HIV and is associated with depression, unemployment, and generally worsened quality of life. Previous work on the cortical mechanism of HIV neuropathy found decreased gray matter volume in the bilateral midbrain, thalamus, and posterior cingulate cortex, but structural connectivity in this context remains under-studied. Here we examine alterations in white matter microstructure using diffusion imaging, hypothesizing that cortical white matter degeneration would be observed in continuation of the peripheral white matter atrophy previously observed in HIV-DSP. Male HIV seropositive patients (n = 57) experiencing varying degrees of HIV neuropathy underwent single-shell diffusion tensor imaging with 51 sampling directions. The scans were pooled using tractography and connectometry to create a quantitative map of white matter tract integrity, measured in generalized fractional anisotropy (GFA). The relationship between GFA and neuropathy severity was evaluated with linear regression. Correction for multiple comparisons was done using false discovery rate (FDR), a statistical method commonly used in genomics and imaging to minimize false positives when thousands of individual comparisons are made. Neuropathy severity was associated with decreased GFA along thalamocortical radiations leading along the lateral thalamus to sensorimotor cortex, with r = -0.405 (p < 0.001; FDR), as well as with the superior bilateral cingulum (r = -0.346 (p < 0.05; FDR)). Among a population of HIV neuropathy patients, greater neuropathy severity was correlated with lower white matter integrity running from midbrain to somatosensory cortex. This suggests ascending deafferentation extending from damaged peripheral nerves further downstream than seen previously, into the axons of third-order neurons. There is also evidence of cingulum degeneration, implying some more complex mechanism beyond the ascending atrophy observed here.

Distal neuropathic pain in HIV is associated with functional connectivity patterns in default mode and salience networks.

HIV-associated distal neuropathic pain (DNP) is one of the most prevalent, disabling, and treatment-resistant complications of HIV, but its biological underpinnings are incompletely understood. While data specific to mechanisms underlying HIV DNP are scarce, functional neuroimaging of chronic pain more broadly implicates the role of altered resting-state functional connectivity within and between salience network (SN) and default mode network (DMN) regions. However, it remains unclear the extent to which HIV DNP is associated with similar alterations in connectivity. The current study aimed to bridge this gap in the literature through examination of resting-state functional connectivity patterns within SN and DMN regions among people with HIV (PWH) with and without DNP. Resting state functional magnetic resonance imaging (rs-fMRI) scans were completed among 62 PWH with HIV-associated peripheral neuropathy, of whom 27 reported current DNP and 35 did not. Using subgrouping group iterative multiple estimation, we compared connectivity patterns in those with current DNP to those without. We observed weaker connectivity between the medial prefrontal cortex (MPFC) and posterior cingulate cortex (PCC) and stronger connectivity between the anterior cingulate cortex (ACC) and thalamus among those reporting DNP. Overall, these findings implicate altered within DMN (i.e., MPFC-PCC) and within SN (i.e., ACC-thalamus) connectivity as potential manifestations of adaptation to pain from neuropathy and/or mechanisms underlying the development/maintenance of DNP. Findings are discussed in the context of differential brain response to pain (i.e., mind wandering, pain aversion, pain facilitation/inhibition) and therapeutic implications.

Toward Composite Pain Biomarkers of Neuropathic Pain-Focus on Peripheral Neuropathic Pain.

Chronic pain affects ~10-20% of the U.S. population with an estimated annual cost of $600 billion, the most significant economic cost of any disease to-date. Neuropathic pain is a type of chronic pain that is particularly difficult to manage and leads to significant disability and poor quality of life. Pain biomarkers offer the possibility to develop objective pain-related indicators that may help diagnose, treat, and improve the understanding of neuropathic pain pathophysiology. We review neuropathic pain mechanisms related to opiates, inflammation, and endocannabinoids with the objective of identifying composite biomarkers of neuropathic pain. In the literature, pain biomarkers typically are divided into physiological non-imaging pain biomarkers and brain imaging pain biomarkers. We review both types of biomarker types with the goal of identifying composite pain biomarkers that may improve recognition and treatment of neuropathic pain.

Association of painful human immunodeficiency virus distal sensory polyneuropathy with aberrant expectation of pain relief: functional magnetic resonance imaging evidence.

Mechanisms underlying chronic neuropathic pain associated with HIV-associated distal sensory polyneuropathy are poorly understood, yet 40% of those with distal neuropathy (or 20% of all people with HIV) suffer from this debilitating condition. Central pain processing mechanisms are thought to contribute to the development of HIV neuropathic pain, yet studies investigating central mechanisms for HIV neuropathic pain are few. Considering the motivational nature of pain, we aimed to examine the degree to which expectation of pain onset and expectation of pain offset are altered in sixty-one male patients with HIV-related distal sensory polyneuropathy with (N = 30) and without (N = 31) chronic neuropathic pain. By contrasting painful (foot) and non-painful (hand) sites between those with and without neuropathic pain, we could identify unique neural structures that showed altered activation during expectation of pain offset or relief. Our results showed no evidence for peripheral mechanisms evidenced by lack of significant between group differences in thermo-sensation, subjective pain response or epidermal nerve fibre density. Likewise, we found no significant differences between groups in subjective or brain mechanisms underlying the expectation of pain onset. Conversely, we found significant interaction within right anterior insula during expectation of pain offset in our study in that individuals in the pain group compared to the no-pain group exhibited increased anterior insula activation on the painful compared to the non-painful site. Our findings are consistent with abnormal processing of expectation of pain offset or abnormal pain relief-related mechanisms potentially due to increased emotional distress regarding the experience of chronic endogenous pain.

Assessment of Cumulative Incidence and Severity of Primary Open-Angle Glaucoma Among Participants in the Ocular Hypertension Treatment Study After 20 Years of Follow-up.

Importance: Ocular hypertension is an important risk factor for the development of primary open-angle glaucoma (POAG). Data from long-term follow-up can be used to inform the management of patients with ocular hypertension. Objective: To determine the cumulative incidence and severity of POAG after 20 years of follow-up among participants in the Ocular Hypertension Treatment Study. Design, Setting, and Participants: Participants in the Ocular Hypertension Treatment Study were followed up from February 1994 to December 2008 in 22 clinics. Data were collected after 20 years of follow-up (from January 2016 to April 2019) or within 2 years of death. Analyses were performed from July 2019 to December 2020. Interventions: From February 28, 1994, to June 2, 2002 (phase 1), participants were randomized to receive either topical ocular hypotensive medication (medication group) or close observation (observation group). From June 3, 2002, to December 30, 2008 (phase 2), both randomization groups received medication. Beginning in 2009, treatment was no longer determined by study protocol. From January 7, 2016, to April 15, 2019 (phase 3), participants received ophthalmic examinations and visual function assessments. Main Outcomes and Measures: Twenty-year cumulative incidence and severity of POAG in 1 or both eyes after adjustment for exposure time. Results: A total of 1636 individuals (mean [SD] age, 55.4 [9.6] years; 931 women [56.9%]; 1138 White participants [69.6%]; 407 Black/African American participants [24.9%]) were randomized in phase 1 of the clinical trial. Of those, 483 participants (29.5%) developed POAG in 1 or both eyes (unadjusted incidence). After adjusting for exposure time, the 20-year cumulative incidence of POAG in 1 or both eyes was 45.6% (95% CI, 42.3%-48.8%) among all participants, 49.3% (95% CI, 44.5%-53.8%) among participants in the observation group, and 41.9% (95% CI, 37.2%-46.3%) among participants in the medication group. The 20-year cumulative incidence of POAG was 55.2% (95% CI, 47.9%-61.5%) among Black/African American participants and 42.7% (95% CI, 38.9%-46.3%) among participants of other races. The 20-year cumulative incidence for visual field loss was 25.2% (95% CI, 22.5%-27.8%). Using a 5-factor baseline model, the cumulative incidence of POAG among participants in the low-, medium-, and high-risk tertiles was 31.7% (95% CI, 26.4%-36.6%), 47.6% (95% CI, 41.6%-53.0%), and 59.8% (95% CI, 53.1%-65.5%), respectively. Conclusions and Relevance: In this study, only one-fourth of participants in the Ocular Hypertension Treatment Study developed visual field loss in either eye over long-term follow-up. This information, together with a prediction model, may help clinicians and patients make informed personalized decisions about the management of ocular hypertension. Trial Registration: ClinicalTrials.gov Identifier: NCT00000125.

Paresthesia Predicts Increased Risk of Distal Neuropathic Pain in Older People with HIV-Associated Sensory Polyneuropathy.

OBJECTIVE: Distal sensory polyneuropathy (DSP) is a disabling consequence of human immunodeficiency virus (HIV), leading to poor quality of life and more frequent falls in older age. Neuropathic pain and paresthesia are prevalent symptoms; however, there are currently no known curative treatments and the longitudinal course of pain in HIV-associated DSP is poorly characterized. METHODS: This was a prospective longitudinal study of 265 people with HIV (PWH) enrolled in the CNS HIV Antiretroviral Therapy Effects Research (CHARTER) study with baseline and 12-year follow-up evaluations. Since pain and paresthesia are highly correlated, statistical decomposition was used to separate the two symptoms at baseline. Multivariable logistic regression analyses of decomposed variables were used to determine the effects of neuropathy symptoms at baseline on presence and worsening of distal neuropathic pain at 12-year follow-up, adjusted for covariates. RESULTS: Mean age was 56 ± 8 years, and 21% were female at follow-up. Nearly the entire cohort (96%) was on antiretroviral therapy (ART), and 82% had suppressed (≤50 copies/mL) plasma viral loads at follow-up. Of those with pain at follow-up (n = 100), 23% had paresthesia at the initial visit. Decomposed paresthesia at baseline increased the risk of pain at follow-up (odds ratio [OR] 1.56; 95% confidence interval [CI] 1.18, 2.07), and decomposed pain at baseline predicted a higher frequency of pain at follow-up (OR 1.96 [95% CI 1.51, 2.58]). CONCLUSIONS: Paresthesias are a clinically significant predictor of incident pain at follow-up among aging PWH with DSP. Development of new therapies to encourage neuroregeneration might take advantage of this finding to choose individuals likely to benefit from treatment preventing incident pain.

Evidence for a novel subcortical mechanism for posterior cingulate cortex atrophy in HIV peripheral neuropathy.

We previously reported that neuropathic pain was associated with smaller posterior cingulate cortical (PCC) volumes, suggesting that a smaller/dysfunctional PCC may contribute to development of pain via impaired mind wandering. A gap in our previous report was lack of evidence for a mechanism for the genesis of PCC atrophy in HIV peripheral neuropathy. Here we investigate if volumetric differences in the subcortex for those with neuropathic paresthesia may contribute to smaller PCC volumes, potentially through deafferentation of ascending white matter tracts resulting from peripheral nerve damage in HIV neuropathy. Since neuropathic pain and paresthesia are highly correlated, statistical decomposition was used to separate pain and paresthesia symptoms to determine which regions of brain atrophy are associated with both pain and paresthesia and which are associated separately with pain or paresthesia. HIV+ individuals (N = 233) with and without paresthesia in a multisite study underwent structural brain magnetic resonance imaging. Voxel-based morphometry and a segmentation/registration tool were used to investigate regional brain volume changes associated with paresthesia. Analysis of decomposed variables found that smaller midbrain and thalamus volumes were associated with paresthesia rather than pain. However, atrophy in the PCC was related to both pain and paresthesia. Peak thalamic atrophy (p = 0.004; MNI x = - 14, y = - 24, z = - 2) for more severe paresthesia was in a region with reciprocal connections with the PCC. This provides initial evidence that smaller PCC volumes in HIV peripheral neuropathy are related to ascending white matter deafferentation caused by small fiber damage observed in HIV peripheral neuropathy.

Catechol-O-methyltransferase polymorphism Val158Met is associated with distal neuropathic pain in HIV-associated sensory neuropathy.

BACKGROUND: Many of those aging with HIV suffer from distal neuropathic pain (DNP) due to HIV-associated sensory neuropathy (HIV-SN). Prior studies have linked chronic pain conditions to a variant of the catechol-O-methyltransferase (COMT), ValMet. This variant confers reduced enzymatic activity and results in higher synaptic dopamine levels. Here we examined the role of ValMet as a predictor of DNP in HIV-SN. METHODS: In 1044 HIV-infected individuals enrolled in CNS HIV Antiretroviral Therapy Effects Research, an observational study across six US institutions, we characterized the relationship between ValMet and DNP in HIV-SN. Participants underwent neurologic examination and genotyping. Stratification into genetic ancestry groups was employed to eliminate bias due to genetic background. FINDINGS: Of 590 participants with HIV-SN, 38% endorsed DNP, 24% reported nonpainful symptoms of neuropathy (paresthesia and numbness), and 38% were asymptomatic. Compared with asymptomatic HIV-SN, ValMet was associated with 2.3 higher odds of DNP. There were no increased odds of nonpainful symptoms. The association remained significant after controlling for other risk factors for DNP: lifetime diagnosis of depression, older age, ancestry, cumulative exposure to dideoxynucleoside antiretrovirals, diabetes, and nadir CD4. Stratified by genetic ancestry, the association between ValMet and DNP was significant in European and African genetic ancestry. INTERPRETATION: ValMet may be a genetic marker for susceptibility to DNP in HIV-SN. Our findings support the notion that differences in pain processing mediated by COMT-related dopamine signaling play a role in susceptibility to DNP in HIV-SN. Because prior studies suggest that the COMT allele may influence dose-response relationships with opioid treatment, knowing COMT genotype could influence management.

Chronic Distal Sensory Polyneuropathy Is a Major Contributor to Balance Disturbances in Persons Living With HIV.

BACKGROUND: Medical comorbidities accumulate in older persons living with HIV (PLWH), causing disability and reduced quality of life. Sensory neuropathy and polypharmacy may contribute to balance difficulties and falls. The contribution of neuropathy is understudied. OBJECTIVE: To evaluate the contribution of chronic distal sensory polyneuropathy (cDSPN) to balance disturbances among PLWH. METHODS: Ambulatory PLWH and HIV- adults (N = 3379) were prospectively studied. All participants underwent a neurologic examination to document objective abnormality diagnostic of cDSPN and reported neuropathy symptoms including pain, paresthesias, and numbness. Participants provided detailed information regarding balance disturbance and falls over the previous 10 years. Balance disturbances were coded as minimal or none and mild-to-moderate. Covariates included age, HIV disease, and treatment characteristics and medications (sedatives, opioids, and antihypertensives). RESULTS: Eleven percent of participants reported balance disturbances at some time during the last 10 years; the rate in PLWH participants exceeding that for HIV- [odds ratio 2.59, 95% confidence interval: 1.85 to 3.64]. Fifty-two percent met criteria for cDSPN. Balance problems were more common in those with cDSPN [odds ratio = 3.3 (2.6-4.3)]. Adjusting for relevant covariates, balance disturbances attributable to cDSPN were more frequent among HIV+ than HIV- (interaction P = 0.001). Among individuals with cDSPN, older participants were much more likely to report balance disturbances than younger ones. CONCLUSIONS: cDSPN contributes to balance problems in PLWH. Assessments of cDSPN in older PLWH should be a clinical priority to identify those at risk and to aid in fall prevention and the ensuing consequences, including bone fractures, subdural hematoma, hospital admissions, and fatal injury.

Risk Factors for Fellow Eye Involvement in Nonarteritic Anterior Ischemic Optic Neuropathy.

BACKGROUND: Nonarteritic anterior ischemic optic neuropathy (NAION) is the most common acute optic neuropathy in individuals older than 50 years. Demographic, ocular, and systemic risk factors for NAION have been identified, and we sought to determine which, if any, of these factors also increase risk of NAION in the fellow eye. METHODS: We performed a retrospective chart review of patients with "ischemic optic neuropathy" (based on International Classification of Disease [ICD] codes) seen at a single eye center between 2007 and 2017. Patients who met diagnostic criteria for unilateral NAION without fellow eye optic neuropathy at diagnosis were included. Demographic information, ocular comorbidities, and systemic diagnoses were recorded, in addition to whether the fellow eye developed NAION during the follow-up period. Univariate and multivariate Cox proportional hazard regression were used to calculate hazard ratios (HRs) for fellow eye involvement. RESULTS: Three hundred eighteen patients were identified by ICD codes, and 119 were included in the study. Twenty-nine (24%) patients developed NAION in the fellow eye over the mean follow-up period of 3.6 years (range: 1 month-11 years). Significant risk factors for fellow eye NAION included the presence of bilateral optic disc drusen (ODD, HR 2.78, 95% confidence interval [CI] 1.12-6.90, P = 0.02) and noncompliance with continuous positive airway pressure (CPAP) in patients with moderate-to-severe obstructive sleep apnea (HR 4.50, 95% CI 1.79-11.3, P = 0.0015). CONCLUSIONS: Bilateral ODD and noncompliance with CPAP when indicated are associated with increased risk of NAION in the fellow eye. Patients with these risk factors should be counseled on the potentially devastating visual consequences of bilateral NAION, and compliance with CPAP should be stressed when appropriate.

HIV Distal Neuropathic Pain Is Associated with Smaller Ventral Posterior Cingulate Cortex.

Objective: . Despite modern antiretroviral therapy, HIV-associated neuropathy is one of the most prevalent, disabling and treatment-resistant complications of HIV disease. The presence and intensity of distal neuropathic pain is not fully explained by the degree of peripheral nerve damage. A better understanding of brain structure in HIV distal neuropathic pain may help explain why some patients with HIV neuropathy report pain while the majority does not. Previously, we reported that more intense distal neuropathic pain was associated with smaller total cerebral cortical gray matter volumes. The objective of this study was to determine which parts of the cortex are smaller. Methods: . HIV positive individuals with and without distal neuropathic pain enrolled in the multisite (N = 233) CNS HIV Antiretroviral Treatment Effects (CHARTER) study underwent structural brain magnetic resonance imaging. Voxel-based morphometry was used to investigate regional brain volumes in these structural brain images. Results: . Left ventral posterior cingulate cortex was smaller for HIV positive individuals with versus without distal neuropathic pain (peak P = 0.017; peak t = 5.15; MNI coordinates x = -6, y = -54, z = 20). Regional brain volumes within cortical gray matter structures typically associated with pain processing were also smaller for HIV positive individuals having higher intensity ratings of distal neuropathic pain. Conclusions: . The posterior cingulate is thought to be involved in inhibiting the perception of painful stimuli. Mechanistically a smaller posterior cingulate cortex structure may be related to reduced anti-nociception contributing to increased distal neuropathic pain.

History of the American Board of Ophthalmology Oral Examination.

The oral examination has been an integral part of certification by the American Board of Ophthalmology (ABO) since its founding in 1916. An overview is provided regarding the history, evolution, and application of new technology for the oral examination. This part of the certifying process allows the ABO to assess candidates for a variety of competencies, including communication skills and professionalism.

Visual Field Outcomes for the Idiopathic Intracranial Hypertension Treatment Trial (IIHTT).

PURPOSE: The Idiopathic Intracranial Hypertension Treatment Trial (IIHTT) showed that acetazolamide provided a modest, significant improvement in mean deviation (MD). Here, we further analyze visual field changes over the 6-month study period. METHODS: Of 165 subjects with mild visual loss in the IIHTT, 125 had perimetry at baseline and 6 months. We evaluated pointwise linear regression of visual sensitivity versus time to classify test locations in the worst MD (study) eye as improving or not; pointwise changes from baseline to month 6 in decibels; and clinical consensus of change from baseline to 6 months. RESULTS: The average study eye had 36 of 52 test locations with improving sensitivity over 6 months using pointwise linear regression, but differences between the acetazolamide and placebo groups were not significant. Pointwise results mostly improved in both treatment groups with the magnitude of the mean change within groups greatest and statistically significant around the blind spot and the nasal area, especially in the acetazolamide group. The consensus classification of visual field change from baseline to 6 months in the study eye yielded percentages (acetazolamide, placebo) of 7.2% and 17.5% worse, 35.1% and 31.7% with no change, and 56.1% and 50.8% improved; group differences were not statistically significant. CONCLUSIONS: In the IIHTT, compared to the placebo group, the acetazolamide group had a significant pointwise improvement in visual field function, particularly in the nasal and pericecal areas; the latter is likely due to reduction in blind spot size related to improvement in papilledema. (ClinicalTrials.gov number, NCT01003639.).

Factors Affecting Visual Field Outcomes in the Idiopathic Intracranial Hypertension Treatment Trial.

BACKGROUND: To determine the prevalence of visual field (VF) performance failures (PF) and treatment failures (TFs), and identify factors associated with PFs in the Idiopathic Intracranial Hypertension Treatment Trial (IIHTT). METHODS: A total of 165 participants from 38 sites with idiopathic intracranial hypertension (IIH) and mild visual loss were randomized to either acetazolamide-plus diet or placebo-plus diet. The IIHTT Visual Field Reading Center evaluated 2950 Swedish Interactive Threshold Algorithm Standard 24-2 VFs from the enrolled participants. A TF was defined when the participant's VF mean deviation (MD) worsened ≥2 to 3 dB from the average baseline MD (range of -2 to -7 dB) with a second retest confirming the visual deterioration. A PF was determined when the participant's: 1) VF results met TF criteria but were not confirmed on retest, 2) deterioration was confirmed on retest but the IIHTT Adjudication Committee concluded a TF was clinically unlikely. RESULTS: TF was detected in 7/165 (4%) of the participants and PF was detected in 35/165 (21%) of the participants on at least 1 examination. Four of the 35 PFs were adjudicated for TF, however based on clinical review by the adjudication committee and a third retest, they were judged as PFs. Of the 2,950 total IIHTT VF examinations, 2.7% met PF criteria. CONCLUSIONS: PF was confirmed in 21% of subjects and in 2.7% of the total number of VF examinations and was reversible on repeat testing. We recommend retesting when perimetric worsening occurs in otherwise clinically stable or improving IIH patients.

Positive Auto-Antibody Activity With Retina and Optic Nerve in Smokers and Non-Smokers: The Controversy Continues.

Auto-antibodies assist with the diagnosis of ocular paraneoplastic syndromes and autoimmune ocular conditions; however, the frequency of positive test results as a possible precursor to future disease is unknown. The frequency of positive antibodies in heavy smokers who may be at risk for autoimmune-related retinopathy and optic neuropathy was evaluated. Serum antibody activity was evaluated through the use of Western blot reactions from pig retina and optic nerve extract. Fifty-one patients were included: 35 patients were smokers (average: 40.9 pack-year history) and 26 patients had no past smoking history. None of the patients had any visual complaints or known eye disease. Of the patients studied, 76.5% (39 patients: 18 smokers, 21 non-smokers) had positive antiretinal antibodies, and 19.6% (10 patients: 3 smokers, 7 non-smokers) had positive antioptic nerve antibodies. Anti-retinal antibodies were seen in a majority of randomly selected patients with and without a past smoking history. Anti-optic nerve bodies were less common, but more prevalent in those who never smoked. The specificity of these antibodies remains greatly uncertain and clinical correlation is warranted.

Predictors of new-onset distal neuropathic pain in HIV-infected individuals in the era of combination antiretroviral therapy.

Despite modern combination antiretroviral therapy, distal neuropathic pain (DNP) continues to affect many individuals with HIV infection. We evaluated risk factors for new-onset DNP in the CNS Antiretroviral Therapy Effects Research (CHARTER) study, an observational cohort. Standardized, semiannual clinical evaluations were administered at 6 US sites. Distal neuropathic pain was defined by using a clinician-administered instrument standardized across sites. All participants analyzed were free of DNP at study entry. New-onset DNP was recorded at the first follow-up visit at which it was reported. Mixed-effects logistic regression was used to evaluate potential predictors including HIV disease and treatment factors, demographics, medical comorbidities, and neuropsychiatric factors. Among 493 participants, 131 (27%) reported new DNP over 2306 visits during a median follow-up of 24 months (interquartile range 12-42). In multivariable regression, after adjusting for other covariates, significant entry predictors of new DNP were older age, female sex, current and past antiretroviral treatment, lack of virologic suppression, and lifetime history of opioid use disorder. During follow-up, more severe depression symptoms conferred a significantly elevated risk. The associations with opioid use disorders and depression reinforce the view that the clinical expression of neuropathic pain with peripheral nerve disease is strongly influenced by neuropsychiatric factors. Delineating such risk factors might help target emerging preventive strategies, for example, to individuals with a history of opioid use disorder, or might lead to new treatment approaches such as the use of tools to ameliorate depressed mood.

Perimetry, retinal nerve fiber layer thickness and papilledema grade after cerebrospinal fluid shunting in patients with idiopathic intracranial hypertension.

BACKGROUND: To investigate the effect of cerebrospinal fluid (CSF) shunting on quantitative perimetry and papilledema in patients with uncontrolled idiopathic intracranial hypertension (IIH). METHODS: We retrospectively reviewed all cases of IIH with CSF shunting at our institution between 2004 and 2011. Perimetry was performed before and after surgery in 15 patients, and the mean deviation (MD) was compared before and after surgery to assess the effect of the intervention. RESULTS: Fourteen of the IIH patients were female and 1 was male. The average age was 34 years. CSF shunting resulted in significant improvement in the perimetric results with an increase in the MD of 5.63 ± 1.19 dB (P < 0.0001). Additionally, average retinal nerve fiber layer (RNFL) thickness measurement by optical coherence tomography decreased by 87.27 ± 16.65 µm (P < 0.0001), and Frisen papilledema grade decreased by 2.19 ± 0.71 (P < 0.0001). CONCLUSIONS: Our results suggest that CSF shunting results in improvement in perimetry, RNFL swelling, and papilledema grade in patients with IIH.

Baseline OCT measurements in the idiopathic intracranial hypertension treatment trial, part I: quality control, comparisons, and variability.

PURPOSE: Optical coherence tomography (OCT) has been used to investigate papilledema in single-site, mostly retrospective studies. We investigated whether spectral-domain OCT (SD-OCT), which provides thickness and volume measurements of the optic nerve head and retina, could reliably demonstrate structural changes due to papilledema in a prospective multisite clinical trial setting. METHODS: At entry, 126 subjects in the Idiopathic Intracranial Hypertension Treatment Trial (IIHTT) with mild visual field loss had optic disc and macular scans, using the Cirrus SD-OCT. Images were analyzed by using the proprietary commercial and custom 3D-segmentation algorithms to calculate retinal nerve fiber layer (RNFL), total retinal thickness (TRT), optic nerve head volume (ONHV), and retinal ganglion cell layer (GCL) thickness. We evaluated variability, with interocular comparison and correlation between results for both methods. RESULTS: The average RNFL thickness > 95% of normal controls in 90% of eyes and the RNFL, TRT, ONH height, and ONHV showed strong (r > 0.8) correlations for interocular comparisons. Variability for repeated testing of OCT parameters was low for both methods and intraclass correlations > 0.9 except for the proprietary GCL thickness. The proprietary algorithm-derived RNFL, TRT, and GCL thickness measurements had failure rates of 10%, 16%, and 20% for all eyes respectively, which were uncommon with 3D-segmentation-derived measurements. Only 7% of eyes had GCL thinning that was less than fifth percentile of normal age-matched control eyes by both methods. CONCLUSIONS: Spectral-domain OCT provides reliable continuous variables and quantified assessment of structural alterations due to papilledema. (ClinicalTrials.gov number, NCT01003639.).

Baseline OCT measurements in the idiopathic intracranial hypertension treatment trial, part II: correlations and relationship to clinical features.

PURPOSE: The accepted method to evaluate and monitor papilledema, Frisén grading, uses an ordinal approach based on descriptive features. Part I showed that spectral-domain optical coherence tomography (SD-OCT) in a clinical trial setting provides reliable measurement of the effects of papilledema on the optic nerve head (ONH) and peripapillary retina, particularly if a 3-D segmentation method is used for analysis.(1) We evaluated how OCT parameters are interrelated and how they correlate with vision and other clinical features in idiopathic intracranial hypertension (IIH) patients. METHODS: A total of 126 subjects in the IIH Treatment Trial (IIHTT) OCT substudy had Cirrus SD-OCT optic disc and macula scans analyzed by using a 3-D segmentation algorithm to derive retinal nerve fiber layer (RNFL) thickness, total retinal thickness (TRT), retinal ganglion cell layer plus inner plexiform layer (GCL+IPL) thickness, and ONH volume. The SD-OCT parameter values were correlated with high- and low-contrast acuity, perimetric mean deviation, Frisén grading, and IIH features. RESULTS: At study entry, the average RNFL thickness, TRT, and ONH volume showed significant strong correlations (r ≥ 0.90) with each other. The same OCT parameters showed a strong (r > 0.76) correlation with Frisén grade and a mild (r > 0.24), but significant, correlation with lumbar puncture opening pressure. For all eyes at baseline, neither visual acuity (high or low contrast) nor mean deviation correlated with any OCT measure of swelling or GCL+IPL thickness. CONCLUSIONS: In newly diagnosed IIH, OCT demonstrated alterations of the peripapillary retina and ONH correlate with Frisén grading of papilledema. At presentation, OCT measures of papilledema, in patients with newly diagnosed IIH and mild vision loss, do not correlate with clinical features or visual dysfunction. (ClinicalTrials.gov number, NCT01003639.).