Clinical challenge: Looking beyond blurred margins

A 60-year-old man presented to an outside ophthalmology clinic with 1 month of progressive vision loss in the right eye (OD). Right optic disc edema was noted. Brain and orbit magnetic resonance imaging revealed right optic nerve and left occipital lobe enhancement. He was seen initially by neurology and neurosurgery and subsequently referred to neuro-ophthalmology for consideration of optic nerve biopsy. He was seen 3 months after his initial symptom onset where vision was light perception OD and a relative afferent pupillary defect with optic nerve edema. OS was unremarkable. A lumbar puncture with flow cytometry was negative for multiple sclerosis and lymphoma. At his oculoplastic evaluation for optic nerve biopsy, his vision was noted to be no light perception OD. Optic nerve biopsy demonstrated non-caseating granulomatous inflammation consistent with neurosarcoidosis. The patient was started on high-dose oral steroids with improvement of disc edema, as well as significant improvement in optic nerve and intracranial parenchymal enhancement, although his vision never improved.

Temporal patterns of visual recovery following pituitary tumor resection: A prospective cohort study

Significant restoration of visual function can occur following pituitary tumor resection, although the time course of visual recovery remains poorly understood. This single-centre, two-year, prospective cohort study investigated the temporal patterns of visual recovery in consecutive patients undergoing pituitary tumor resection, between 2009 and 2018. Eyes were stratified based on pre-operative optical coherence tomography (OCT) retinal nerve fibre layer (RNFL) thickness measurements, with thin RNFL being defined as those within the fifth-percentile of age-matched normative values, and normal RNFL as those above the fifth-percentile. Visual function and OCT parameters were assessed pre-operatively, and at 6 weeks, 6 months, and 2 years post-operatively. 456 eyes of 228 patients (mean ± SD age, 53 ± 15 years) were included, of which 114 (25%) eyes had thin RNFL pre-operatively. Visual field recovery was observed in both groups during the first 6 weeks post-operatively (all Q ≤ 0.02), although improvements in visual field parameters between 6 weeks to 6 months were limited to eyes with thin RNFL (both Q < 0.05). No further improvements in visual function were detected beyond 6 months in both groups (both Q > 0.50). Similar trends were observed in linear regression analysis according to baseline visual function in both groups. In summary, eyes with normal RNFL thickness at baseline experienced most of their recovery within the first six weeks following surgery, while eyes with thin RNFL exhibited gradual improvements during the first six months. These findings have important implications when providing patient counselling and prognostication in the pre-operative setting.

Prognostic Utility of Optical Coherence Tomography for Long-Term Visual Recovery Following Pituitary Tumor Surgery

PURPOSE

To investigate the association between optical coherence tomography (OCT) parameters and long-term visual recovery following optic chiasm decompression surgery.

DESIGN

Prospective cohort study.

METHODS

Consecutive patients who underwent pituitary or parasellar tumor resection between January 2009 to December 2018 were recruited in a single-center, 2-year prospective, longitudinal cohort study. Best-corrected visual acuity, visual fields, and OCT retinal nerve fiber layer (RNFL) thickness, macular thickness and volume were assessed preoperatively, and at 6 weeks, 6 months, and 2 years postoperatively. Long-term visual field recovery and maintenance were defined as a mean deviation of >-3 at 24 months, and visual acuity recovery and maintenance were defined as a logarithm of minimal angle of resolution (logMAR) of 0 (Snellen 20/20) or better at 24 months.

RESULTS

A total of 239 patients (129 men, 110 women; mean ± SD age: 52 ± 16 years) were included. Multiple logistic regression analysis demonstrated that increased inferior RNFL thickness (per 10 μm) was associated with higher odds of long-term visual field recovery and maintenance (odds ratio [OR]: 1.26; 95% confidence interval [CI]: 1.12-1.41; Q < 0.001), and greater superior RNFL thickness (per 10 μm) was associated with higher odds of visual acuity recovery and maintenance (OR: 1.13; 95% CI: 1.03-1.27; Q = 0.031). A multivariable risk prediction model developed for long-term visual field recovery and maintenance that incorporated age, preoperative visual function, and RNFL thickness demonstrated C-statistics of 0.83 (95% CI: 0.72-0.94).

CONCLUSION

Preoperative RNFL thickness was associated with long-term visual recovery and maintenance following chiasmal decompression. The multivariable risk prediction model developed in the present study may assist with preoperative patient counseling and prognosis.

Bilateral abducens nerve palsy due to septic thrombophlebitis

Purpose

To report a case of septic thrombophlebitis producing bilateral abducens nerve palsy.

Observation

A 65 year-old woman with recent sinus surgery experienced the onset of horizontal diplopia during treatment for bacteremia. Computer tomography of head and a neck ultrasonography showed right internal jugular vein occlusion. Ophthalmology examination was consistent with bilateral abducens nerve palsy. She was treated with systemic antibiotics and antiplatelet therapy with resolution of the internal jugular vein occlusion. The diplopia improved over a six-months.

Conclusion and importance

Our patient had Lemierre syndrome with an unusual presentation. The patient was treated for septic thrombophlebitis with a resolution of her ocular symptoms.

The Utility of Color Duplex Ultrasonography in the Diagnosis of Giant Cell Arteritis: A Prospective, Masked Study. (An American Ophthalmological Society Thesis)

PURPOSE

To evaluate the diagnostic yield and concordance of color duplex ultrasound (CDU) of the superficial temporal artery (STA), temporal artery biopsy (TAB), and American College of Rheumatology (ACR) criteria in the diagnosis of giant cell arteritis (GCA).

METHODS

Prospective, masked study of all patients evaluated in one institution suspected of having GCA. All patients with a suspected diagnosis of GCA were admitted for pulsed intravenous corticosteroids. Patients underwent serologic work-up and ACR criteria were documented. All patients had a CDU and TAB performed within 3 days of initiation of systemic corticosteroid therapy. Main outcome measure: Concordance of CDU and TAB. Secondary outcome measures: Concordance between unilateral and bilateral CDU and TAB by side and segment, concordance between TAB and ACR criteria, and statistical analysis of serologic markers for GCA.

RESULTS

The diagnosis of biopsy-proven GCA was found in 14 of 71 (19.7%) patients. The sensitivity of CDU compared to the reference standard of TAB ranged between 5.1% and 30.8% depending on the signs studied on CDU and correlation of specific TAB parameters. Of the serologic studies, a platelet count threshold of 400,000μL had the highest positive (18.32) and lowest negative (0.37) likelihood ratios for a diagnosis of GCA.

CONCLUSIONS

In this study, CDU showed minimal value in diagnosing GCA compared to TAB. There was poor correlation between CDU results and ACR criteria for GCA. The threshold platelet count had higher positive and negative predictive values for GCA than CDU and is a useful serologic marker for GCA.

Toxic optic neuropathy: an unusual cause

A 60-year-old woman with a history of chronic alcoholism and tobacco use presented with the complaint of a painless decrease in vision in both eyes. She lost vision first in the left eye then in the right eye. She admitted consuming at least one 16 ounce bottle of over the counter mouthwash daily and denied consumption of any other alcohols, methanol, or antifreeze. She stated that her vision had been continuing to deteriorate in both eyes. Her best-corrected visual acuity was 4/200 in each eye. Color vision was nil in each eye. Her pupils were sluggish bilaterally, and her optic discs were flat and hyperemic with peripapillary hemorrhages. Her visual fields revealed central scotomas bilaterally. The magnetic resonance imaging of the brain and lumbar puncture were within normal limits. Antinuclear antibody, human leukocyte antigen-B27 genotyping, and B12 were normal; serum thiamine was low. While continuing to ingest mouthwash, her vision decreased to count fingers at 2 feet, and maculopapillary bundle pallor developed. She was started on folate and thiamine supplementation. Once she discontinued mouthwash, her vision improved to 20/400 bilaterally, and her central scotomas improved. This case demonstrates an alcohol-induced toxic optic neuropathy from mouthwash ingestion with some visual recovery after discontinuation of the offending agent.

A novel mutation in a case of dominant optic atrophy?

A 39-year-old healthy woman presented for decreased vision at distance and near for 4 years. She also noted a decrease in her color vision. Her best-corrected visual acuities were 20/70 in each eye. Her visual fields were abnormal, and she had bilateral sluggish pupils, impaired color vision, and optic disc pallor. The magnetic resonance imaging of the brain, heavy metal screen, autoimmune work-up, B12, B6, folate, erythrocyte sedimentation rate, rapid plasma reagin, and Lyme titer were all normal. Optical coherence tomography of the macula and electroretinogram were normal; the visual evoked potential was unrecordable in both eyes. She denied a family history of similar ocular issues, and genotyping of the OPA1 gene revealed a novel previously unreported mutation at IVS12+10T >C.

Differentiation of compressive from glaucomatous optic neuropathy with spectral-domain optical coherence tomography

PURPOSE

To compare optic disc topography in eyes with compressive optic neuropathy (CON) and open-angle glaucoma (OAG) using spectral-domain (SD) optical coherence tomography (OCT) and Heidelberg retinal tomograph (HRT) (Heidelberg Engineering GmbH, Heidelberg, Germany).

DESIGN

Cross-sectional, observational study.

PARTICIPANTS

A total of 200 eyes from 123 patients with CON (69 eyes) or OAG (58 eyes) and controls (73 eyes).

METHODS

Univariate and multivariate analyses of HRT parameters, SD-OCT circumpapillary retinal nerve fiber layer (RNFL) thickness, and optic nerve head (ONH) parameters.

MAIN OUTCOME MEASURES

Circumpapillary RNFL, OCT ONH parameters, and HRT parameters.

RESULTS

The univariate analysis of OCT parameters demonstrated significant differences between the temporal and nasal quadrants; clock hours 3 (55 vs. 73 μm), 4, 8 (93.9 vs. 70.7 μm), 9, and 10; vertical cup-to-disc ratio (C:D) (0.6 vs. 0.8) and cup volume (0.2 vs. 0.5) (P<0.001) between patients with CON and OAG, respectively. The CON discs were significantly different from normal discs for all OCT parameters except cup volume. The CON discs were not significantly different from normal discs for HRT parameters, except for mean RNFL thickness and cup shape measure. The OAG discs were significantly different from normal discs in all HRT and OCT parameters (P<0.001). Multivariate analysis demonstrated that the OCT 3 o'clock temporal sector, average C:D ratio, vertical C:D ratio, and cup volume measurements were able to differentiate OAG from CON.

CONCLUSIONS

Compressive optic neuropathy is associated with significantly thinner nasal and temporal sectors compared with OAG, whereas OAG results in larger cups and cup volume with OCT measurements. The Heidelberg retinal tomograph is not able to differentiate CON from normal discs.

Visual acuity and pattern of visual field loss at presentation in pituitary adenoma

Our purpose was to analyse the demographics, prevalence and pattern of visual field defects in patients with pituitary adenoma. We prospectively recruited 103 consecutive patients (206 eyes) presenting to a neurosurgical unit with pituitary adenoma. Ophthalmological examination and standard automated perimetry (Humphrey, 24-2 threshold) was performed. Severity of visual field defects was also assessed. The mean population age was 53.9 years (standard deviation=15). Visual loss was the most common reason for presentation (39%) followed by endocrine abnormality (21%) and headache (15%). Patients with endocrine abnormality on presentation were 10.9 years younger than those presenting with visual loss (p=0.001). Bitemporal defects were the most prevalent pattern (n=22, 41%) followed by homonymous defects (n=7, 13%). Of the patients with visual field loss, 33% had unilateral visual field defects. The mean visual acuity in those with bitemporal defects was 6/7.5 with half of these patients having 6/6 vision in both eyes. In conclusion, the majority of patients with pituitary adenoma have visual acuity better than 6/7.5 despite having visual field defects. While a bitemporal pattern of visual field loss is the most common, a significant proportion of patients had unilateral and altitudinal defects. Assessment of the visual field is essential to rule out chiasmal compression.

Macular thickness predictive of visual field sensitivity in ischaemic optic neuropathy

PURPOSE

To investigate the ability of optical coherence tomography (OCT) parameters of macular thickness (MT) and peripapillary retinal nerve fibre layer (RNFL) thickness to differentiate eyes with nonarteritic anterior ischaemic optic neuropathy (NAION) from uninvolved eyes and to identify the relationship between macular and RNFL parameters and visual field sensitivity (VFS).

METHODS

Thirty patients with unilateral NAION participated in a prospective observational cross-sectional study. Patients underwent Humphrey visual field (SITA Standard 24-2, HVF) testing and OCT to measure MT and RNFL. The contralateral uninvolved eye was used as controls. Areas under the receiver operating characteristic curves (AUROCs) of MT and RNFL for discriminating NAION from control eyes were also determined. The prespecified outcome measure was the correlation between RNFL, MT and mean deviation (MD).

RESULTS

Average RNFL and MT were thinner in NAION eyes: 72.8 μm versus 98.9 μm (p<0.0001) and 231.9 μm (SD, 21.4) vs. 251.1 μm (SD, 14.8; p=0.0001), respectively. The largest AUROCs were for average MT (0.87) and average RNFL thickness (0.88). Overall, macular parameters showed stronger correlation with VFS than RNFL parameters. The highest correlation was average MT (0.71; p<0.0001) followed by RNFL parameter nasal quadrant RNFL (0.40; p=0.030).

CONCLUSION

Both MT and RNFL show strong correlations with level of VFS in NAION. Macular thickness showed more robust correlations with VF and provides strong surrogate marker of the level of damage in NAION.

Neuroimaging and acute ocular motor mononeuropathies: a prospective study

OBJECTIVE

To evaluate the necessity of neuroimaging in patients with acute, isolated ocular motor mononeuropathies.

METHODS

A prospective case series evaluating diagnostic technology results in 93 patients older than 50 years with acute isolated mononeuropathies was performed. Patients were included in the study if they had new-onset diplopia with an isolated cranial neuropathy (cranial nerve III, IV, or VI palsy) and no other signs of neurologic dysfunction. All patients had gadolinium-enhanced magnetic resonance imaging (MRI). The number of patients with lesions noted on MRI and the overall cost of imaging the patients were determined. Cost analysis of the MRI was conducted using Current Procedural Terminology codes and Medicare costs in 2010 dollars. Cost utility was estimated using cost data as well as published utility values for adults with diplopia and sex-specific life tables for life expectancy in the United States.

RESULTS

Four of 93 patients had lesions on MRI; however, only 1 of the 93 patients had a lesion related to the cranial mononeuropathy. The total modeled cost of imaging for these 93 patients was $131,688 to determine an underlying cause in 1 patient with no change in treatment. The estimated cost utility for the patient with a causative lesion found by MRI was $90.19 for diagnosis alone.

CONCLUSIONS

It may not be medically necessary to perform MRI scanning on every patient with an isolated cranial nerve III, IV, or VI palsy. In adults older than 50 years with an isolated mononeuropathy, physicians should carefully review the patients' history and findings to determine which patients to image at the initial evaluation.

Optic disc morphology in open-angle glaucoma compared with anterior ischemic optic neuropathies

Purpose. To compare optic disc topography performed by confocal laser ophthalmoscopy in eyes with nonarteritic anterior ischemic optic neuropathy (NAION), arteritic anterior ischemic optic neuropathy (AAION), and open-angle glaucoma (OAG), adjusting for the amount of retinal ganglion cell (RGC) loss, as measured by nerve fiber layer (NFL) thickness and average visual field loss. Methods. At four referral centers, patients who met specific diagnostic criteria for OAG (103 persons, 152 eyes), NAION (53 persons, 57 eyes), or AAION (18 persons, 20 eyes) underwent Heidelberg Retinal Tomography (HRT; Heidelberg Engineering, Heidelberg, Germany), Stratus Optical Coherence Tomography (OCT; Carl Zeiss Meditec, Inc., Dublin, CA), and Humphrey visual field testing (HFA; Carl Zeiss Meditec, Inc.). HRT parameters were compared in univariate and multivariate models, accounting for degree of RGC loss by either OCT NFL thickness or visual field mean deviation (MD). Acute AION occurred at least 6 weeks before testing. Results. After adjustment for degree of injury according to either MD or mean NFL thickness, all HRT parameters were significantly different between OAG and both NAION and AAION. With similar damage, OAG eyes had larger, deeper cups; smaller rims; more cup volume; and less rim volume (all P < or = 0.001). There were differences in disc topography between NAION and AAION, but they were not consistent for both measures of damage. Disc area and MD were also significantly associated with many HRT parameters. NFL thickness was greater at the same MD for both AAION and NAION compared with OAG. Conclusions. NAION and AAION cause loss of RGCs, but have significantly different disc topography compared with OAG at a given level of RGC loss.

Technique selection for orbital decompression: combined endoscopic and transconjunctival versus combined endoscopic and transantral approach

Surgical orbital decompression is indicated for patients with compressive optic neuropathy, exposure keratopathy, an uncontrolled elevation of intraocular pressure, globe subluxation, and disfiguring proptosis secondary to Graves ophthalmopathy. Controversy exists, however, regarding the selection of surgical technique to achieve orbital decompression. We compared the results of our combined transnasal endoscopic and transconjunctival approach with those of our combined transnasal endoscopic and transantral approach to orbital decompression. We conducted a retrospective chart review of patients who had undergone medial- and inferior-wall orbital decompression from January 1994 through January 2004. During that time, 189 combined medial- and inferior-wall orbital decompressions were performed on 124 patients; 51 combined endoscopic and transantral decompressions were performed on 28 patients, and 138 combined endoscopic and transconjunctival decompressions were performed on 96 patients. Patient demographics and the degree of preoperative proptosis were statistically equal in the 2 groups. The incidence of optic neuropathy in the transantral group was significantly higher than the incidence in the entire group (p = 0.03), and the incidence of exposure keratopathy was significantly lower in the transantral group than in the entire group (p = 0.03). Postoperatively, the reduction in proptosis in the 2 groups was statistically equivalent, but the transconjunctival group had a significantly lower incidence of both infraorbital hypesthesia (p< 0.0001) and early rhinosinusitis (p = 0.008). Three cases of globe ptosis and 2 of infraorbital neuralgia occurred. No cases of visual loss, worsened optic neuropathy, diplopia in patients without preexisting diplopia, cerebrospinal fluid leak, significant epistaxis, or periorbital hematoma were noted. We conclude that combined endoscopic and transconjunctival orbital decompression offers equivalent efficacy with less postoperative infraorbital hypesthesia and early rhinosinusitis than does combined endoscopic and transantral orbital decompression.

In vivo retinal nerve fiber layer thickness measured by optical coherence tomography predicts visual recovery after surgery for parachiasmal tumors

PURPOSE

Restoration of visual function after neurosurgery for parachiasmal tumors is variable and unpredictable. The current study was conducted to determine whether in vivo retinal nerve fiber layer (RNFL) thickness measurements predict the visual recovery of such patients.

METHODS

Forty patients undergoing surgical resection of parachiasmal lesions were prospectively assessed before surgery with a neuro-ophthalmic examination, involving standard automated visual field (VF) testing and optical coherence tomography (OCT) measurements of RNFL thickness, which was the prespecified marker for axonal loss. Tests were repeated within 6 weeks after surgery.

RESULTS

Thinner preoperative RNFL thickness was associated with worse visual acuity (VA) and VF mean deviation (MD). Patients with normal preoperative RNFL had significant improvement in mean VA after surgery, from 20/40 to 20/25 (P = 0.028), whereas patients with thin RNFL did not improve (20/80 to 20/60, P = 0.177). Eyes with normal RNFL showed improvement in MD (-7.0 dB before surgery, -3.5 dB after surgery, P = 0.0007) unlike eyes with thin RNFLs, which had no significant improvement after surgery (-15.3 dB before and -13.3 dB after surgery, P = 0.191). RNFL thickness increased by 1% after surgery among all eyes (P = 0.04). Eyes with severe VF defects (MD </= -10 dB) but normal preoperative RNFL thickness showed a postoperative improvement in MD of 14.6 dB compared with 1.6 dB (P < 0.0001) in eyes with thin RNFL before surgery, despite no difference in MD before surgery (normal RNFL MD, -22.3 dB; thin RNFL MD, -20.8 dB; P = 0.7).

CONCLUSIONS

Patients who have objectively measurable RNFL loss at the time of surgery for chiasmal compressive lesions are less likely to have return of VA or VF after surgery.

Brightness sensitivity and color perception as predictors of relative afferent pupillary defect

PURPOSE

To characterize the relationship between brightness sensitivity and color perception and relative afferent pupillary defect (RAPD) in patients with optic neuropathy.

METHODS

The "swinging flashlight test" was used to diagnose RAPD, the degree of which was quantified by neutral density filters, in 325 consecutive patients in a case-control study. A separate examiner, masked to the pupillary findings, then assessed participants for Ishihara color plate reading, brightness sense, and red perception. The latter two were quantified by asking the patient to score (out of 100%) brightness (of a light source) or redness (of an object) of the two eyes relative to each other. Pearson correlation coefficients and receiver operating characteristic (ROC) curves were calculated.

RESULTS

Brightness sense (r = -0.79; 95% confidence interval [CI], -0.84 to -0.73; P < 0.0001), red perception (r = -0.73; 95% CI, -0.79 to -0.65; P < 0.0001), and Ishihara color plate reading (r = -0.68; 95% CI, -0.79 to -0.66; P < 0.0001) were each strongly and highly significantly correlated with the diagnosis and degree of RAPD. Brightness sense and red perception were each able to discriminate almost all the area under ROC for the diagnosis of RAPD (area of 0.99; 95% CI, 0.98-1.00; P < 0.0001; area of 0.93; 95% CI, 0.90-0.96; P < 0.0001, respectively). Sensitivity and specificity of brightness sense in detection of RAPD were 99% (95% CI, 0.97-1.00) and 95% (95% CI, 0.91-0.98), respectively. The red perception test was only slightly less accurate.

CONCLUSIONS

Rapid, simple assessments of brightness sense and color perception provide accurate methods to facilitate the diagnosis of optic neuropathy and may prove to be valuable in screening for optic neuropathy or alternatives to the swinging flashlight test.

Missing the Bull's Eye

We report a patient with a long history of hydroxychloroquine use. Clinical examinations had been performed according to American Academy of Ophthalmology guidelines with no abnormalities. A multifocal electroretinogram (mfERG) was performed to further assess macular function. Multifocal ERG may detect macular dysfunction earlier than the currently recommended screening guidelines in patients with potential for macular toxicity from hydroxychloroquine.

Occurrence of Cerebral Venous Sinus Thrombosis in Patients with Presumed Idiopathic Intracranial Hypertension

PURPOSE

To report the rate of occurrence of cerebral venous sinus thrombosis (CVST) in patients with presumed idiopathic intracranial hypertension (IIH).

DESIGN

Retrospective chart review.

PARTICIPANTS

All patients diagnosed with papilledema from November 1, 2002, through October 31, 2003, at 3 tertiary care neuro-ophthalmology centers.

METHODS

Consecutive patients with a diagnosis of papilledema from 3 tertiary care neuro-ophthalmology centers were identified. Patients with space-occupying lesions, hydrocephalus, or meningitis were excluded. The remaining patients were evaluated with lumbar puncture, magnetic resonance imaging (MRI), and magnetic resonance venography (MRV).

MAIN OUTCOME MEASURES

The rate of occurrence of CVST in patients with presumed IIH.

RESULTS

One hundred thirty-one patients with papilledema were identified. Excluding patients with mass lesions, meningitis, or hydrocephalus, the occurrence of CVST was 10 (9.4%) of 106 patients with presumed IIH. Two additional patients had a diagnosis of suspected CVST. Cerebral venous sinus thrombosis was diagnosed in 1 of the 10 patients with MRI alone, whereas it was evident in all 10 patients with MRV. Underlying risk factors for CVST were identified in 9 of 10 patients.

CONCLUSIONS

Cerebral venous sinus thrombosis accounts for 9.4% of patients with presumed IIH in 3 tertiary care neuro-ophthalmology services. Magnetic resonance venography in combination with MRI is recommended to identify this subgroup of patients.

Correlation of Retinal Nerve Fiber Layer Measured by Scanning Laser Polarimeter to Visual Field in Ischemic Optic Neuropathy

OBJECTIVE

To evaluate the relationship between retinal nerve fiber layer (RNFL) measurement with scanning laser polarimetry (SLP) and standard automated perimetry (SAP) in nonarteritic anterior ischemic optic neuropathy (NAION).

METHODS

In this prospective observational case series, all subjects (28 eyes with NAION) underwent SAP and SLP. The RNFL retardation measurements and visual field test points were grouped into 6 corresponding sectors. The contralateral uninvolved eye was used as control. The relationship between RNFL retardation and SAP was evaluated with the Spearman nonparametric technique and linear regression analysis. The main outcome measure was correlation of SLP RNFL parameters and SAP.

RESULTS

Global and sectoral SLP parameters showed a significant difference in affected eyes compared with controls. The strongest correlations were seen between mean deviation and number (r = -0.524; P = .004), ellipse modulation (r = 0.5026; P = .006), and maximum modulation (r = 0.526; P = .004). Superior sectoral visual field indexes showed a strong correlation with inferior RNFL changes (r = 0.522; P<.008). Linear regression confirmed a strong relationship between the superior sectoral visual field indexes and the inferior RNFL.

CONCLUSION

Scanning laser polarimetry was able to identify structural changes of the RNFL globally and in the inferior SLP sector with functional loss in NAION.

Relationship between Retinal Nerve Fiber Layer and Visual Field Sensitivity as Measured by Optical Coherence Tomography in Chiasmal Compression

PURPOSE

To investigate the spatial relationship between retinal nerve fiber layer (RNFL) thickness measured with optical coherence tomography (OCT) and visual field sensitivity (VFS) measured by standard automated perimetry (SAP) in chiasmal compression.

METHODS

Twenty-six patients with chiasmal compression were enrolled. RNFL thickness was measured with the StratusOCT and VFS with SAP (Humphrey Field Analyzer; both from Carl Zeiss Meditec, Dublin, CA). Relationships between RNFL thickness (in clock hours, hemifields, and sectors) and VFS (zones were divided into hemifields, quadrants, and sectors based on a validated visual field map) expressed in a decibel scale and 1/lambert (L) were evaluated by linear and nonlinear regression. Coefficients of determination (R(2)) were calculated by using a multivariate model.

RESULTS

Average RNFL thickness correlated strongly with pattern standard deviation (PSD; R = 0.622) and mean deviation (MD; R = 0.413). The four strongest correlations were between the 8 o'clock OCT position (temporal disc), with the temporal hemifield (R = -0.813), the superotemporal quadrant (R = -0.847), the inferotemporal quadrant (R = -0.855), and the field sector representing the papillomacular bundle (R = -0.809). Coefficients of determination improved significantly in all sectors when time since surgery was included in the regression model-most notably, average thickness and 1/L (R(2) = 0.35-0.49), the decibels (R(2) = 0.31-0.47), and the temporal sector (R(2) = 0.44-0.57).

CONCLUSIONS

This is the first study to compare the structure-function correlation of RNFL measured by OCT with SAP in patients with chiasmal compression. RNFL is topographically related globally and sectorally to decreased SAP, with the temporal sectors showing the strongest correlations. The correlation between RNFL and VFS strengthens as the time from surgical intervention increases.

Prevalence of a Normal C-Reactive Protein with an Elevated Erythrocyte Sedimentation Rate in Biopsy-Proven Giant Cell Arteritis

OBJECTIVE

The erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) are laboratory tests that have been said to have a strong correlation with a positive temporal artery biopsy in patients with suspected giant cell arteritis (GCA). Published reports suggest that the CRP is a more sensitive diagnostic indicator of GCA and can be elevated when the ESR is normal. It is also clear that the CRP and ESR can both be normal or both be elevated in patients with biopsy-proven GCA and that the CRP can be elevated when the ESR is normal. The purpose of this study was to ascertain if the CRP can be normal when the ESR is elevated in biopsy-proven GCA.

DESIGN

Retrospective, longitudinal, comparative study.

PARTICIPANTS

One hundred nineteen patients from 6 major tertiary-care university-affiliated medical centers.

METHODS

The charts from 119 patients with temporal artery biopsies positive for GCA were reviewed for age, gender, pretreatment ESR, and pretreatment CRP.

MAIN OUTCOME MEASURES

The ESR in millimeters per hour Westergren was graded as normal or abnormal based on 2 validated formulas. The CRP was graded as normal or abnormal based on established criteria set forth in the literature as well as at The Johns Hopkins Hematology laboratory.

RESULTS

In this study, the ESR had a sensitivity of 76% to 86%, depending on which of 2 formulas were used, whereas an elevated CRP had a sensitivity of 97.5%. The sensitivity of the ESR and CRP together was 99%. Only 1 of the 119 patients (0.8%) presented with a normal ESR and normal CRP (double false negative); 2 patients (1.7%) had a normal CRP despite an elevated ESR according to both formulas.

CONCLUSION

Although most patients with GCA have both an elevated ESR and CRP, there can be nonconcordance of the 2 blood tests. Although such nonconcordance is most often a normal ESR but an elevated CRP, the finding of an elevated ESR and a normal CRP also is consistent with GCA. The use of both tests provides a slightly greater sensitivity for the diagnosis of GCA than the use of either test alone.

Orbital Lymphoma With Concomitant Sarcoid-Like Granulomas

A 41-year-old man presented with chronic eyelid swelling, conjunctival injection, and decreased ocular motility in all gaze directions. MRI showed bilateral enlarged extraocular muscles, including the tendons. Laboratory tests revealed elevated levels of angiotensin-converting enzyme. An orbital biopsy showed collections of monotonous small lymphocytes, and granulomatous inflammation that included multinucleated giant cells, predominantly Langhans type. Flow cytometric analysis of tissue demonstrated a light chain-restricted clonal population of B cells, a finding that confirmed the morphologic impression of lymphoma. This case demonstrates that elevated angiotensin-converting enzyme and granulomatous inflammation can occur in lymphoma. Careful histopathologic examination and flow cytometric analysis are essential to avoid an erroneous diagnosis that could lead to inappropriate management.

Multifocal ERG in ethambutol associated visual loss

AIM

To determine the anatomical site and extent of electrophysiological dysfunction in patients with ethambutol associated visual loss.

METHODS

A comparative case series. Four patients with ethambutol associated visual loss underwent multifocal electroretinography (mERG). Two patients had advanced visual loss while two had early signs of toxicity. The N1-P1, N1, P1 amplitudes, N1, and P1 latencies were compared to 10 age and sex matched controls.

RESULTS

mERG abnormalities were detected in the ethambutol treated patients. The N1 amplitude was significantly lower in the ethambutol treated patients than in the control group.

CONCLUSION

Ethambutol is possibly toxic to the retina, and not only the optic nerve. The multifocal ERG may be of value to diagnose and monitor patients taking ethambutol.

Poor prognosis of visual outcome after visual loss from giant cell arteritis

OBJECTIVE

To evaluate the incidence and extent of visual recovery in patients with giant cell arteritis (GCA) treated with high doses of systemic corticosteroids.

DESIGN

Multicenter prospective case series.

PARTICIPANTS

Thirty-four consecutive patients with biopsy-proven GCA and visual loss seen at either Wills Eye Hospital in Philadelphia or Auckland Hospital in New Zealand from 2001 to 2004 were evaluated prospectively.

METHODS

All patients underwent a complete neuro-ophthalmic evaluation that included Snellen visual acuity, pseudoisochromatic Ishihara color plates, visual fields, intraocular pressure, slit-lamp examination, and binocular ophthalmoscopy. Formal visual field testing was performed on all patients who were capable of completing the test. All patients were treated with a standard protocol of 1 g of IV methylprednisolone daily for 3 days followed by oral prednisone 60 or 80 mg (depending on patient weight). Patients were evaluated initially at 2-week intervals (14-19 days) and then monthly (4-5 weeks), with subsequent dosages of prednisone modified based on erythrocyte sedimentation rate, C-reactive protein, and patient symptoms. At each visit, patients underwent a repeat complete neuro-ophthalmic evaluation.

MAIN OUTCOME MEASURES

Alterations in visual acuity, visual field, and color vision.

RESULTS

Patients with visual loss from GCA had a mean visual acuity of 20/400. Visual deterioration occurred in 27% of eyes within the first week despite high-dose IV corticosteroids. Fifteen percent of eyes showed an improvement of visual acuity within the first month, but only 5% have corresponding improvement in visual field.

CONCLUSIONS

Visual recovery is uncommon in patients who lose vision from GCA. Recovery in visual acuity is not associated with visual field or color vision improvement in this series. Visual deterioration occurs in approximately 27% of eyes despite high-dose IV methylprednisolone. The greatest risk of visual deterioration is in the first 6 days.

Isolated optic nerve lymphoma diagnosed by optic nerve biopsy

PURPOSE

To report a case of isolated optic nerve lymphoma diagnosed by optic nerve biopsy.

DESIGN

Case report.

METHODS

A 66-year-old woman was referred to the Neuro-Ophthalmology Service because of a decrease in visual acuity and right optic disk edema.

RESULTS

A magnetic resonance image of the brain showed only enhancement of the optic nerve. An examination that included ANA, c-ANCA, p-ANCA, Lyme titers, FTA-ABS, ACE level, chest x-ray, and lumbar puncture was negative. Because of rapid progression on clinical examination and serial imaging, an optic nerve biopsy was performed, which showed B-cell lymphoma.

CONCLUSION

Optic nerve lymphoma can be confused with a variety of inflammatory and neoplastic infiltrations of the optic nerve on clinical and radiographic examinations. Optic nerve biopsy can be valuable in diagnosing isolated optic nerve lymphoma if other diagnostic tests are unrevealing, but the procedure carries considerable risk of loss of visual acuity and should be recommended judiciously.

Comparison of Arteritis and Nonarteritic Anterior Ischemic Optic Neuropathies with the Heidelberg Retina Tomograph

OBJECTIVE

Quantitative data are not available regarding the morphological appearance of optic nerve morphology after arteritic anterior ischemic optic neuropathy (AAION) and nonarteritic anterior ischemic optic neuropathy (NAION). The purpose of this study is to evaluate the appearance of the optic nerve head in patients after AAION and NAION with the Heidelberg Retina Tomograph (HRT).

DESIGN

Prospective comparative observational study.

PARTICIPANTS

Thirty-eight patients with either unilateral AAION (15) or NAION (23).

METHODS

Heidelberg Retina Tomograph images were taken of both affected and unaffected eyes. The quantitative changes in the optic nerve head were morphologically evaluated and compared with those of the normal contralateral eyes.

MAIN OUTCOME MEASURES

Heidelberg Retina Tomograph parameters were analyzed using the uninvolved contralateral eye as a control.

RESULTS

The ratio between cup area and disc area was 42% larger in the affected eyes in the NAION group than in the fellow eyes (P = 0.03, t test). In the AAION patients, the ratio between cup area and disc area was 116% larger in involved eyes than in their fellow eyes (P = 0.0003, t test). In addition, in the AAION group, relative to their fellow eyes, the rim area was 27% smaller (P = 0.0006), cup volume was 160% larger (P = 0.021, t test), mean cup depth was 29% larger, cup shape measure differed by 41% (suggesting more excavation), and mean retinal nerve fiber layer thickness was 30% less. Relative to the fellow eyes in the NAION group, the rim area was 6% smaller (P = 0.13, Student's t test), and the cup shape measure was 13% different, although these were not statistically significant. When the uninvolved eyes of the NAION and AAION groups were compared directly, there was no statistical difference between any of the HRT parameters, except mean cup depth (0.09 vs. 0.14 mm, respectively; P = 0.02).

CONCLUSIONS

This study is the first to demonstrate quantitatively an enlargement and excavation of the optic cup after an event of AAION, but not NAION. The eyes affected with AAION showed significant excavation and enlargement of the optic cup when compared with contralateral uninvolved eyes. All HRT-generated parameters showed changes consistent with increased enlargement and excavation of AAION-involved eyes. These changes were not observed in eyes that experienced an event of NAION.

Incidence of Infraorbital Hypesthesia and Sinusitis After Orbital Decompression for Thyroid-Related Orbitopathy: A Comparison of Surgical Techniques

PURPOSE

To compare the incidence of postoperative infraorbital (V2) hypesthesia and sinusitis between transantral/Caldwell-Luc and transconjunctival orbital decompression for thyroid-related orbitopathy.

METHODS

A retrospective review of all orbital decompressions from January 1994 to January 2001 performed by one surgeon was done. Seventy-eight patients (133 orbits) with thyroid-related orbitopathy underwent orbital decompression for compressive optic neuropathy, exposure keratopathy, or uncontrolled intraocular pressure. Main outcome measures were the presence of V2 hypesthesia and sinusitis determined at 3 postoperative evaluations (1 to 2 weeks, 1 to 3 months, 3 to 6 months).

RESULTS

The incidence of V2 hypesthesia in the transconjunctival group declined from 29.2% (19/65) to 6.1% (4/65), whereas the incidence of V2 hypesthesia in the transantral/Caldwell-Luc group decreased from 68.2% (43/63) to 46% (29/63) over the postoperative course. The rate of sinusitis in the transconjunctival group stayed constant at 6.1% (4/65) at early and late postoperative visits, whereas the transantral group rate of sinusitis declined from 33.3% (21/63) to 9.5% (6/63).

CONCLUSIONS

Transconjunctival orbital decompression results in a statistically significant decrease of early and late postoperative infraorbital hypesthesia and early postoperative sinusitis when compared with the transantral approach.

Nonarteritic anterior ischemic optic neuropathy in patients with sleep apnea while being treated with continuous positive airway pressure

PURPOSE

To report three cases of nonarteritic anterior ischemic optic neuropathy (NAION) that occurred in patients with sleep apnea syndrome (SAS) while being treated with continuous positive airway pressure (CPAP).

DESIGN

A prospective, noncomparative case series.

METHODS

Prospective review of 108 patients with NAION diagnosed between 2002 and 2003 to identify any patients who developed NAION while being treated for SAS with CPAP.

RESULTS

One patient had bilateral sequential NAION and two patients had unilateral NAION despite treatment with CPAP for SAS. All the patients were being treated with CPAP for a period ranging from 4 months to 6 years before the onset of NAION.

CONCLUSIONS

In this series, CPAP did not prevent the development of NAION in SAS patients. Larger observational studies are needed to study the benefit of CPAP in preventing NAION in patients with SAS.

Fractionated stereotactic radiotherapy for parasellar meningiomas: a preliminary report of visual outcomes

BACKGROUND/AIM

Fractionated stereotactic radiotherapy (FSRT) is a new treatment for brain tumours that are close to critical structures, such as the visual apparatus. This study aims to assess the visual outcomes for patients with parasellar meningioma following FSRT.

METHODS

A retrospective, non-comparative case series of 13 patients with parasellar meningiomas who were treated in one institution with FSRT between January 1995 and January 2001.

RESULTS

13 patients (26 eyes) were followed for a mean of 2 years. Visual acuity improved in four eyes (12.5%), remained stable in 18 eyes (75%), and worsened in three eyes (12.5%). Visual field improved in 15 eyes (57%), remained stable in six eyes (23%), and worsened in four eyes (15%). No adverse visual outcome occurred as a result of radiation.

CONCLUSION

These preliminary findings suggest that FSRT is a safe and effective treatment for parasellar meningiomas.

Orbital radiotherapy for thyroid-related orbitopathy

PURPOSE OF REVIEW

Orbital radiotherapy has been one of the primary treatment modalities for moderate to severe thyroid-related orbitopathy. In this review the authors discuss the role of orbital radiotherapy in this disease with particular emphasis on questions raised by recent studies.

RECENT FINDINGS

Despite its widespread use, until recently there have been few well-designed, randomized clinical trials on the role of orbital radiotherapy for thyroid-related orbitopathy. Although most the literature points to a favorable effect of orbital radiotherapy, recent studies have provided us with conflicting results.

SUMMARY

Orbital radiotherapy remains a safe and a widely used treatment option for severe and progressive thyroid-related orbitopathy. More randomized clinical trials are needed, especially to examine the role of orbital radiotherapy for severe thyroid-related orbitopathy characterized by severe congestion and/or compressive optic neuropathy with and without the use of corticosteroids. There is a wide consensus among clinicians that this subgroup of patients is the most frequent one to which orbital radiotherapy is offered.

The antiphospholipid antibody syndrome: diagnostic aspects

PURPOSE OF REVIEW

The antiphospholipid antibody syndrome is an important cause of arterial and/or venous thrombosis. In this review the authors discuss recent trends in the clinical and laboratory diagnosis of this syndrome that are of relevance to ophthalmologists.

RECENT FINDINGS

The diagnostic criteria of antiphospholipid antibody syndrome have been reviewed and revalidated recently. Few prospective studies have been conducted to determine the prevalence of antiphospholipid antibodies in patients with retinal vascular occlusion and the spectrum of ophthalmologic findings in patients with established antiphospholipid syndrome. New antibody tests for antiphospholipid antibody syndrome are available with increased sensitivity and specificity, but lack of standardization, and interassay and interlaboratory variation makes it difficult to determine their clinical value.

SUMMARY

Ophthalmologists should be familiar with the spectrum of clinical manifestation of antiphospholipid syndrome, the diagnostic criteria of this disease, and be able to carry out a basic laboratory workup for this entity. A high index of suspicion for this disorder is also important in making the diagnosis.

Visual loss despite anticoagulation in radiation-induced optic neuropathy

Radiation therapy to the brain may produce necrosis and loss of function months after completion of the treatment. The case is presented of a 62-year-old man who developed radiation-induced optic neuropathy 2 years after treatment for a glioma of the left temporal lobe, despite being on anticoagulation therapy. Although anticoagulation appears to be beneficial in cerebral radiation necrosis, its usefulness in the treatment of radiation-induced optic neuropathy is unclear.

Pseudotumor cerebri

PURPOSE OF REVIEW

To discuss the current standard in diagnosis and treatment of pseudotumor cerebri (PTC), the syndrome of increased intracranial pressure without a brain tumor. Since PTC is a diagnosis of exclusion, the differential diagnostic work-up is of special importance.

RECENT FINDINGS

Modern imaging techniques have facilitated the differential diagnosis of PTC. Various therapeutic options are available to prevent irreversible visual loss. New treatment modalities are being explored, but the standard therapy has undergone little change in the past years.

SUMMARY

PTC, a potentially blinding disease, most commonly manifests with headache and slightly blurred vision due to papilledema. This review seeks to present a methodical approach to its diagnosis and treatment.