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Chapter 191 – Ischemic Optic Neuropathy, Diabetic Papillopathy, and Papillophlebitis

Chapter 191 – Ischemic Optic Neuropathy, Diabetic Papillopathy, and Papillophlebitis

 

ANTHONY C. ARNOLD

 

 

 

 

 

DEFINITION

• Acute, painless optic neuropathy occurring predominantly in patients over 50 years of age.

• Additional acute pathologies of the optic disc may be associated with diabetes and venous congestion.

 

KEY FEATURES

• Optic disc edema, often pale or segmental (in anterior ischemic optic neuropathy).

• Dimming of vision, dyschromatopsia, afferent pupillary defect, and altitudinal or other optic disc–related visual field loss (in anterior ischemic optic neuropathy).

• Minimal optic nerve dysfunction (in diabetic papillopathy).

• Big blind spot with relatively normal optic nerve function (in papillophlebitis).

 

ASSOCIATED FEATURES

• Peripapillary flame hemorrhages.

• Peripapillary arteriolar narrowing.

 

 

 

ISCHEMIC OPTIC NEUROPATHIES

INTRODUCTION

Optic nerve ischemia most frequently occurs at the optic nerve head, where structural crowding of nerve fibers and reduction of the vascular supply may combine to impair perfusion to a critical degree. Such acute anterior ischemia produces optic disc edema. The most common such syndrome is termed anterior ischemic optic neuropathy (AION).[1] Generally, AION is categorized as either arteritic (associated with temporal arteritis) or nonarteritic ( Table 191-1 ). A number of syndromes that share similar characteristics also may be ischemic in origin—diabetic papillopathy, hypertensive papillopathy, “AION of the young,” preinfarct disc edema in nonarteritic AION, and migrainous optic neuropathy. Optic nerve ischemia affects the intraorbital portion of the nerve less frequently, with no visible disc edema, and has been termed posterior ischemic optic neuropathy. This rare syndrome has been reported most often in cases of vasculitis, including systemic lupus erythematosus and temporal arteritis, or anemia with hypotension, and is rare.

EPIDEMIOLOGY AND PATHOGENESIS

Nonarteritic anterior ischemic optic neuropathy (NAION) is the most common acute optic neuropathy in patients over 50 years of age, with an estimated annual incidence in the United States of 2.3–10.2 per 100,000 population,[2] [3] some 6000–8000 new cases each year. No gender predisposition exists, but the disease occurs with significantly higher frequency in the white than in African-American or Hispanic populations.[2] [4] The incidence of arteritic anterior ischemic optic neuropathy (AAION) is significantly lower (0.36 per 100,000 population annually in patients over 50 years of age[2] ).

Arteritic Anterior Ischemic Optic Neuropathy

Ample evidence exists that AAION results from short posterior ciliary artery (SPCA) vasculitis and the resultant optic nerve head infarction. Human autopsy studies of acute AAION demonstrate optic disc edema with ischemic necrosis of the prelaminar, laminar, and retrolaminar portions of the nerve and infiltration of the SPCAs by chronic inflammatory cells. Segments of these vessels in some cases have been occluded by inflammatory thickening and thrombus.[5]

Fluorescein angiographic data support the histopathological evidence of involvement of the SPCAs in AAION. Delayed filling of the optic disc and choroid is a consistent feature. Hayreh[6] emphasized a correlation between the delay in filling of an affected segment of disc and the adjacent choroid and related it to a specific branch of the SPCA system. In addition, extremely poor or absent filling of the choroid has been depicted as a characteristic of AAION and has been suggested as one useful factor by which to differentiate AAION from NAION. Delayed completion of choroidal fluorescein filling that averages 30–69 seconds has been reported in AAION, compared with a mean of 5–13 seconds in NAION.[7] [8]

Nonarteritic Anterior Ischemic Optic Neuropathy

The rapid onset, stable course with generally poor recovery, association with vasculopathic risk factors, and similarity to AAION have implied a vascular cause for NAION as well, but the direct evidence remains limited. Several histopathological reports document laminar and retrolaminar infarction, but cases of uncomplicated NAION are rare, and none has confirmed vasculopathy within the SPCAs or their distal branches. The most commonly proposed pathogenic theory states that insufficiency of the optic disc circulation, exacerbated by structural crowding of nerve fibers and supporting structures at the nerve head, eventually reaches a point at which inadequate oxygenation produces ischemia and swelling of the disc. These features may be mild and subclinical (no visual loss), reversible to some degree, or irreversible (infarction). In some cases, a cycle of ischemia, axonal swelling, microvascular compression, and further ischemia may lead to progressive nerve damage. Knox et al.[9] have recently documented cavernous degeneration within ischemic regions of the optic nerve head, with distortion of adjacent axons, theorizing that this process may be responsible for the progressive course in some cases. Periodic nocturnal systemic hypotension and the location of the optic disc in a watershed zone between distributions of lateral and medial SPCAs may be contributing factors.[10]

Fluorescein angiographic studies in NAION also suggest impaired optic disc perfusion. Detailed quantitative analysis of

 

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Figure 191-1 Fluorescein angiogram, early arteriovenous phase, in nonarteritic anterior ischemic optic neuropathy. The temporal portion of the optic disc fills normally (small arrows), but the remaining sectors demonstrate markedly delayed filling (large arrows) approximately 10 seconds later.

 

 

TABLE 191-1 — COMPARISON OF MAJOR FEATURES OF ARTERITIC AND NONARTERITIC ANTERIOR ISCHEMIC OPTIC NEUROPATHY (AION)

Feature

Arteritic AION

Nonarteritic AION

 

Age (mean years)

70

60

 

Sex ratio

Female > male

Male = female

 

Associated symptoms

Headache, scalp tenderness, jaw claudication

Pain occasionally noted

 

Visual acuity

Up to 76% <20/200 (6/60)

Up to 61% >20/200 (6/60)

 

Disc

Pale > hyperemic edema

Hyperemic > pale edema

 

 

Cup normal

Cup small

 

Mean erythrocyte sedimentation rate (mm/h)

70

20–40

 

Fluorescein angiogram

Disc and choroid filling delay

Disc filling delay

 

Natural history

Improvement rare

Improvement in up to 43%

 

 

Fellow eye in up to 95%

Fellow eye in <30%

 

Treatment

Corticosteroids

None proved

 

 

 

prelaminar optic disc and peripapillary choroidal filling in NAION confirms significantly delayed disc filling when compared with age-matched controls.[11] Delay in a segment of disc ( Fig. 191-1 ), by at least 5 seconds, was present in 75.6% of such cases.[11] In contrast, peripapillary choroidal filling was not delayed consistently and not significantly more than the degree of segmental delay often found in normal subjects. These findings suggest that the impaired flow to the optic nerve head in NAION is distal to the SPCAs themselves, possibly at the level of the paraoptic branches that supply the optic nerve head directly.

OCULAR MANIFESTATIONS

AION typically becomes apparent with the rapid onset of painless, unilateral visual loss manifested by decreased visual acuity, visual field, or both. The level of visual acuity impairment varies widely, from minimal loss to no light perception, and the visual field loss may conform to any pattern of deficit related to the optic disc. An altitudinal field defect is most common, but generalized depression, broad arcuate scotomas, and cecocentral defects also are seen. A relative afferent pupillary defect invariably is present with monocular optic neuropathy. The optic disc is edematous at onset, and edema occasionally precedes visual loss by weeks to months.[12] Although pallid edema has been described as the hallmark of AION ( Fig. 191-2 ), it is common to see hyperemic swelling ( Fig. 191-3 ), particularly in the nonarteritic form. The disc most often is swollen diffusely, but a segment of more prominent involvement frequently is present (see Fig. 191-3 ), and

 

 

Figure 191-2 Fundus view, anterior ischemic optic neuropathy. The optic disc demonstrates pale, diffuse edema.

either focal or diffuse surface telangiectasia is not unusual and may be quite pronounced. Commonly, flame hemorrhages are located adjacent to the disc, and the peripapillary retinal arterioles frequently are narrowed.

Arteritic Anterior Ischemic Optic Neuropathy

In 5–10% of cases, AION may occur as a manifestation of the vasculitis associated with temporal arteritis. Patients who have the arteritic form usually note other symptoms of the disease—headache (most common), jaw claudication, and temporal artery or scalp tenderness are those aligned most frequently with a final diagnosis of temporal arteritis. Malaise, anorexia, weight loss, fever, proximal joint arthralgia, and myalgia also are noted commonly; however, the disease occasionally manifests with visual loss in the absence of overt systemic symptoms, so-called occult temporal arteritis.

Typically, AAION is exhibited in elderly patients, with a mean age of 70 years, as severe visual loss (visual acuity <20/200 [6/60] in the majority). It may be preceded by transient visual loss similar to that of carotid artery disease; this finding is extremely unusual in the nonarteritic form and, when present, is highly suggestive of arteritis.[13] [14] Pallor is associated with the edema of the optic disc more frequently in AAION than in the nonarteritic form. Choroidal ischemia may be associated with the optic neuropathy and produces peripapillary pallor and edema deep to the retina, or it may occur with no optic disc involvement. The disc of the fellow eye is of normal diameter most frequently, with a normal physiological cup (see NAION below).[15]

 

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Figure 191-3 Fundus view, nonarteritic anterior ischemic optic neuropathy. The hyperemic disc edema is more prominent superiorly. Focal surface telangiectasia of disc vessels is seen superotemporally (arrows).

Nonarteritic Anterior Ischemic Optic Neuropathy

In 90–95% of cases, AION is unrelated to temporal arteritis. The nonarteritic form of the disease occurs in a relatively younger age group (mean age of 60 years) and usually is associated with less severe visual loss. Frequently, visual impairment is reported upon awakening, possibly related to nocturnal systemic hypotension.[10] The initial course of visual loss may be static (with little or no fluctuation of visual level after the initial loss) or progressive (with either episodic or visual loss that declines steadily over weeks to months prior to eventual stabilization). The progressive form has been reported in 22%[16] to 37%[17] of NAION cases. Usually no associated systemic symptoms occur, although periorbital pain is described occasionally. Fellow eye involvement is estimated to occur in 12–19% by 5 years after onset.[18] Recurrent episodes of visual loss that result from NAION in the same eye are extremely rare and occur most often in young patients.

The optic disc edema in NAION may be diffuse or segmental, hyperemic or pale, but pallor occurs less frequently than it does in AAION. A focal region of more severe swelling often is seen and typically displays an altitudinal distribution, but it does not correlate consistently with the sector of visual field loss.[11] Diffuse or focal telangiectasia (see Fig. 191-3 ) of the edematous disc may be present, occasionally prominent enough to resemble a vascular mass or neovascularization. This finding may represent microvascular shunting from ischemic to nonischemic regions of the optic nerve head, so-called luxury perfusion. The optic disc in the contralateral eye typically is small in diameter and demonstrates a small or absent physiological cup.[15] The disc appearance in such fellow eyes ( Fig. 191-4 ) has been described as the disc at risk, with postulated structural crowding of the axons at the level of the cribriform plate, associated mild disc elevation, and disc margin blurring without overt edema.

DIAGNOSIS AND ANCILLARY TESTING

The most important early step in the management of AION is the differentiation of the arteritic from the nonarteritic form of the disease. Measurement of the erythrocyte sedimentation rate (ESR) is standard. Active temporal arteritis usually is associated with an elevation of ESR to 70–120?mm/h, and in acute AION that is associated with other typical features, this finding suggests the arteritic form; in most cases it should prompt immediate corticosteroid therapy and confirmatory temporal artery biopsy (see below). The test has significant limitations, however, with normal measurements found in an estimated 16% of biopsy-proved cases.[19] Conversely, abnormally high readings occur normally with increasing age and with other diseases, most commonly occult malignancy, other inflammatory disease, and diabetes. Measurement of serum C-reactive protein (CRP), another acute-phase plasma protein, may aid in diagnosis. Hayreh

 

 

Figure 191-4 Fellow eye in nonarteritic anterior ischemic optic neuropathy. The optic disc is small in diameter, with absent physiological cup and slight blurring of the nasal margin.

 

 

 

 

Figure 191-5 Typical temporal arteritis. A, Histological section shows a vasculitis involving all coats of the temporal artery. B, Increased magnification shows the typical giant cell–granulomatous inflammation. (A–B, courtesy of Dr. MM Rodrigues.)

et al.[20] reported 97% specificity for temporal arteritis in cases of AION in which both ESR >47?mm/hr and CRP >2.45?mg/dl were found.

Confirmation of the diagnosis of temporal arteritis by superficial temporal artery biopsy is recommended in any case of AION in which a clinical suspicion of arteritis exists based on age, associated systemic symptoms, severity of visual loss, and elevated ESR and CRP levels. Positive biopsy findings, such as intimal thickening, internal limiting lamina fragmentation, and chronic inflammatory infiltrate with giant cells, provides support for long-term systemic corticosteroid therapy ( Fig. 191-5 ). A negative biopsy result, however, does not rule out arteritis; both discontinuous arterial involvement (“skip lesions”) and solely contralateral temporal artery inflammation may result in false-negative results. In the face of negative initial biopsy, consideration is given to contralateral biopsy in cases with high clinical suspicion of temporal arteritis. Recent reports indicate a 3–5% false-negative error rate.[21]

DIFFERENTIAL DIAGNOSIS

The differential diagnosis of AION includes idiopathic optic neuritis, particularly in patients under 50 years of age; other forms of optic nerve inflammation, such as those related to

 

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syphilis or sarcoidosis; infiltrative optic neuropathies; anterior orbital lesions that produce optic nerve compression; and idiopathic forms of optic disc edema, which include diabetic papillopathy and papillophlebitis. Optic neuritis may resemble AION with regard to rate of onset, pattern of visual field loss, and optic disc appearance. In most cases, however, the patient’s age, lack of pain with eye movement, and pallor or segmental configuration of the disc edema enable differentiation. Early disc filling delay on fluorescein angiography may confirm ischemia. Syphilitic or sarcoid-associated optic neuritis often is associated with other intraocular inflammatory signs, which should prompt further testing. Orbital lesions typically produce gradually progressive visual loss. Associated signs of orbital disease, such as mild exophthalmos, lid abnormalities, or eye movement limitation, may suggest the use of neuroimaging to detect anterior orbital inflammation or tumor. Diabetic papillopathy and papillophlebitis are discussed below.

SYSTEMIC ASSOCIATIONS

AAION is known to be a manifestation of temporal arteritis. NAION has been reported in association with a number of diseases that could predispose to reduced perfusion pressure or increased resistance to flow within the optic nerve head. Systemic hypertension has been documented in up to 47% of patients who have NAION[22] and diabetes in up to 24%.[22] Repka et al.[23] indicated that the prevalences of both hypertension and diabetes are increased over those of the control population in NAION patients in the age range 45–64 years, but that in patients over 64 years of age, no significant difference exists from those of the general population. Diabetics in particular show a predisposition to NAION at a young age.

Carotid occlusive disease, itself, does not appear to be associated directly with NAION in most cases. However, indirect evidence shows increased central nervous system, small vessel, ischemic disease in patients who have NAION, based on magnetic resonance imaging (MRI) data.[24] Early reports did not indicate that the incidence of prior or subsequent cerebrovascular or cardiovascular events is increased, but more recent studies indicate that they are both more common than in the normal population, particularly in patients who have hypertension or diabetes.[25] Subsequent mortality, however, is not affected.[25]

Also, NAION has been reported in association with multiple forms of vasculitis, acute systemic hypotension, migraine, optic disc drusen, and idiopathic vaso-occlusive diseases. Other risk factors, such as hyperopia, smoking, the presence of human lymphocyte antigen A29, and hyperlipidemia have been proposed. Recent reports of the association of hyperhomocystinemia with AION, particularly in patients under 50, are inconclusive.[26] Prothrombotic risk factors, such as protein C and S and antithrombin III deficiencies, factor V Leiden mutation, and cardiolipin antibodies, do not seem to be associated with AION.[27]

TREATMENT

Arteritic Anterior Ischemic Optic Neuropathy

Early treatment of AAION is essential and must be instituted immediately in any suspected case of temporal arteritis. High-dose systemic corticosteroids are standard; the use of intravenous methylprednisolone at 1?g/day for the first 3 days has been recommended for AAION when the patient is in the acute phase of severe involvement, because this mode of therapy produces higher blood levels of medication more rapidly. Oral prednisone in the range of 60–100?mg/day may be used initially and for follow-up to intravenous pulse therapy; alternate day regimens do not suppress the disease effectively. Treatment usually reduces systemic symptoms within several days. A positive response is so typical that if it does not occur, an alternate disease process should be considered.

Nonarteritic Anterior Ischemic Optic Neuropathy

There is no proven effective therapy for NAION. Oral corticosteroids at standard dosage (1?mg/kg per day) are not beneficial, and megadose intravenous therapy has not been evaluated systematically. Optic nerve sheath decompression (ONSD) surgery has been attempted, based on the theory that reduction of perineural subarachnoid cerebrospinal fluid pressure might improve local vascular flow or axoplasmic transport in the optic nerve head, and thus reduce tissue injury in reversibly damaged axons. The Ischemic Optic Neuropathy Decompression Trial[4] compared ONSD surgery in 119 patients with no treatment in 125 controls. The study revealed no significant benefit for treatment and a possible, although not proven, harmful effect; it was recommended that ONSD not be performed for NAION. The 2-year follow-up study confirmed the lack of beneficial effect.[28] Hyperbaric oxygen, by marked elevation of the dissolved oxygen content in the blood, provides increased tissue oxygenation that might reduce damage in reversibly injured axons. A controlled clinical pilot study of hyperbaric oxygen in 22 patients who had acute NAION, however, has shown no beneficial effect.[29] Johnson et al.[30] reported a beneficial effect for oral levodopa on the visual outcome for NAION, but the study was controversial,[31] and the effect is considered unproved. Neuroprotective agents have shown a beneficial effect in animal models of optic nerve damage and are currently being studied in NAION. The effect of aspirin in reducing risk of fellow eye involvement is unclear. [32] [33] Studies are emerging to test whether pentoxifylline may ameliorate the visual loss following NAION. There is a theoretical basis for assuming that it may increase blood flow in the region by rheological alterations.[34]

COURSE AND OUTCOME

Arteritic Anterior Ischemic Optic Neuropathy

The major goal of therapy in AAION is to prevent visual loss in the fellow eye. Untreated, such involvement occurs in 54–95% of cases,[35] [36] typically within 4 months. With corticosteroid therapy, the rate of such breakthrough is reduced to an estimated 13%. Prognosis for visual recovery in the affected eye that has treatment generally is poor, but recent reports suggest a 15–34% improvement rate,[35] [37] which is higher with intravenous than with oral therapy. Worsening of vision in spite of therapy has been reported in 9–17% of cases.[35] [37]

Nonarteritic Anterior Ischemic Optic Neuropathy

The course of untreated NAION varies considerably. Reports indicate that 24–43% of cases demonstrate spontaneous improvement of visual acuity by three Snellen lines or more.[4] [16] Improvement has been reported to occur in roughly 30% of this subgroup, as well. Whether NAION is static or progressive, visual acuity and field stabilize after several months. Within 6 weeks, occasionally sooner, the optic disc becomes visibly atrophic, either in a sectorial ( Fig. 191-6 ) or diffuse pattern. Further progression or recurrent episodes are extremely rare after 2 months and, if present, should prompt evaluation for another cause of optic neuropathy.

LASIK

There are several reports suggesting an association between optic neuropathy and LASIK (laser in situ keratomileusis). The patients in these reports developed acute visual loss following LASIK and all had clinical evidence of optic neuropathy. Unfortunately, none of these patients could experience significant recovery and eventually all developed optic atrophy in the affected eye.

The reason for this association is unknown but may be related to the marked increase in intraocular pressure that occurs during a portion of the procedure.[38] [39]

 

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Figure 191-6 Optic disc, nonarteritic anterior ischemic optic neuropathy. The disc, 2 months after onset of inferior visual field loss, is segmentally atrophic superiorly (arrows), with sparing and resolving edema inferiorly.

POSTERIOR ISCHEMIC OPTIC NEUROPATHY

Posterior ischemic optic neuropathy is caused by infarction of the optic nerve posterior to the lamina cribrosa. This probably reflects a watershed-type infarct, because most patients have low hematocrit levels and hypotension.

The condition is usually of sudden onset with bilateral involvement, following massive bleeding with or without surgery.[40]

Several studies have investigated the risk factors that may predispose to this condition. Prolonged intraoperative hypotension, postoperative anemia, and facial swelling commonly were found.[40]

The incidence of posterior ischemic optic neuropathy might be reduced significantly by compensating for the contributory factors.

DIABETIC PAPILLOPATHY

PATHOGENESIS

The pathogenesis of diabetic papillopathy is unclear. Early investigators postulated either a toxic effect on the optic nerve secondary to abnormal glucose metabolism or a vascular disturbance of the inner disc surface, similar to that which produces retinal edema, with the resultant microvascular leakage into the disc. The most commonly proposed theory suggests diabetic papillopathy to be a mild form of NAION, with reversible ischemia of both the prelaminar and inner surface layers of the optic nerve head.[41] Edema of the optic nerve head in the absence of significant visual dysfunction and not secondary to elevated intracranial pressure occurs in several disorders as follows:

• Asymptomatic optic disc edema, which evolves to typical NAION weeks to months after initial symptoms[13]

• Asymptomatic disc edema of the fellow eye in patients who have NAION, which may either progress to NAION or resolve spontaneously

• Disc edema in association with systemic hypertension, which resolves without sequelae as blood pressure is normalized

Diabetic papillopathy fits this category, as well. The prominent surface telangiectasias may represent vascular shunting from prelaminar to ischemic vascular beds. The frequent occurrence of a crowded optic disc in the fellow eye (see below),[42] as in NAION, also supports an ischemic mechanism.

OCULAR MANIFESTATIONS

Early reports of diabetic papillopathy depicted the acute onset of unilateral or bilateral disc edema in young, type 1 diabetics, without the usual defects in visual field and pupillary function associated with NAION or optic neuritis [41] [42] ; a recent report included a substantial number of older patients with type 2 diabetes. [43]

 

 

 

 

 

 

Figure 191-7 Optic disc in diabetic papillopathy. A, Nonspecific hyperemic disc edema. B, Surface vessels show marked telangiectasia, in which dilated vessels generally follow a radial distribution. C, Contrast with diabetic optic disc neovascularization; note the irregular, random branching pattern of surface vessels.

The currently accepted criteria for the diagnosis of diabetic papillopathy include:

• Presence of diabetes (approximately 70% type 1, 30% type 2)

• Optic disc edema (unilateral in roughly 60%)

• Only mild optic nerve dysfunction

To use visual acuity levels as criteria is difficult, because co-existing maculopathy is a common confounding feature, but over 75% of reported cases measured 20/40 (6/12) or better. The absence of ocular inflammation or elevated intracranial pressure also is essential to the diagnosis.

Although younger patients predominate (approximately 75% of those reported are under the age of 50 years), those affected may be of any age and typically experience either no visual complaints or vague, nonspecific visual disturbance, such as mild blurring or distortion; transient visual obscuration has been reported rarely. Pain is absent, as are other ocular or neurological symptoms.

 

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The involved optic discs may demonstrate either nonspecific hyperemic edema or, in approximately 55% of cases, marked telangiectasia of the inner surface microvasculature ( Figs. 191-7,A and B ); pale swelling typically has been a criterion for exclusion and suggests AION. The surface telangiectasia is so prominent in many cases that it may be mistaken for neovascularization ( Fig. 191-7, C ).

True disc neovascularization occasionally is superimposed on the edema of diabetic papillopathy. The fellow eye frequently demonstrates crowding, with a small cup-to-disc ratio similar to the configuration seen in patients who have NAION.[43]

Diabetic retinopathy usually is present (in more than 80% of reported cases) at the time of onset of papillopathy, but it varies in severity. It is associated with cystoid macular edema in about 25% of cases and neovascularization in approximately 9%.

DIFFERENTIAL DIAGNOSIS

Conditions that may simulate diabetic papillopathy include papilledema (elevated intracranial pressure), hypertensive papillopathy, optic disc neovascularization, papillitis, NAION, and papillophlebitis. Symptoms of elevated intracranial pressure usually differentiate papilledema, and in bilateral cases with such symptoms, neuroimaging and lumbar puncture must be considered. Disc edema related to systemic hypertension typically does not demonstrate prominent telangiectasia and usually is associated with hypertensive retinopathy; blood pressure measurement is important in suspected cases. Papillitis and NAION both demonstrate significant optic nerve dysfunction, as evidenced by afferent pupillary defect and visual field loss. Papillophlebitis typically shows more prominent retinal venous congestion, peripheral retinal hemorrhages and, possibly, retinal vascular sheathing (see below).

COURSE AND OUTCOME

Although systemic corticosteroids have been used in isolated cases, no proven therapy exists for this disorder. Untreated, the optic disc edema gradually resolves over a period of 2–10 months, to leave minimal optic atrophy in about 20% of cases and subtle, if any, visual field loss. Visual acuity at the time of resolution of edema is 20/40 (6/12) or better in about 80% of cases; the remainder of patients suffer visual impairment because of maculopathy. The long-term visual prognosis for patients who have diabetic papillopathy, however, is limited by the associated diabetic retinopathy. Proliferative changes, with attendant complications, develop in approximately 25% of cases.

PAPILLOPHLEBITIS

A syndrome of unilateral retinal venous congestion and optic disc edema in healthy young patients was originally termed papillophlebitis by Lonn and Hoyt in 1966.[44] Similar clinical entities have been described as optic disc vasculitis,[45] benign retinal vasculitis, mild retinal and papillary vasculitis, and big blind-spot syndrome. The syndrome is a subset of central retinal vein occlusion in the young,[46] in which the disc edema and the retinal venous distention are unusually prominent. Investigators have suggested that it results from central retinal vein inflammation at the disc, with secondary venous occlusion and disc edema. To date, however, histopathological studies have been limited to severe, atypical cases of retinal vasculitis, and proof of phlebitis in this syndrome is not available.

The disorder typically manifests with mild symptoms of unilateral visual blurring, photopsia, or transient visual obscuration, without headache, ocular pain, or other complaints. Visual acuity typically is normal or is diminished mildly on the basis of macular hemorrhage or edema. An afferent pupillary defect is absent, color vision is normal, and visual field testing

 

 

 

 

Figure 191-8 Papillophlebitis. A, Fundus view, which shows marked venous congestion, moderate optic disc edema, and retinal hemorrhages. B, Fluorescein angiography, which illustrates disc leakage associated with retinal venous dilation, filling delay, and staining.

shows enlargement of the physiological blind spot. Minimal additional field abnormality may be present because of retinal involvement. Fundus examination demonstrates marked retinal venous engorgement in association with hyperemic optic disc edema ( Fig. 191-8, A ). Retinal hemorrhages that extend to the equatorial region are present in many cases, but additional signs of inflammation or ischemia, such as retinal periphlebitis or capillary nonperfusion, are noted only infrequently. Occasionally, a cilioretinal artery obstruction will be present concurrently.

The differential diagnosis of papillophlebitis includes unilateral papilledema, papillitis and optic perineuritis, orbital compressive lesions, diabetic papillopathy, and arteriosclerotic central retinal vein occlusion. The prominent retinal venous distention, involvement of the peripheral retina with hemorrhages, and the lack of symptoms of elevated intracranial pressure, evidence of optic neuropathy or orbitopathy, and the presence of systemic diseases such as diabetes and hypertension all aid in differentiation.

Fluorescein angiography typically demonstrates marked retinal venous dilation,[45] staining, and leakage, in association with circulatory slowing ( Fig. 191-8, B ); the regions of capillary occlusion seen with diabetic retinopathy and ischemic central retinal vein occlusion are demonstrated only rarely. Late staining and leakage from the disc is common but nonspecific.

On the basis of the presumed inflammatory process, glucocorticoids, both systemic and injected locally, have been used in many of the reported cases. Their value is unproved, however, because the disease tends to follow a benign course if untreated. Retinal and optic disc changes resolve after 6–18 months, usually with no significant sequelae; persistent visual loss is unusual. Retinal venous sheathing and opticociliary collateral vessels are not uncommon on late follow-up examinations, but neovascularization rarely occurs.

 

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2. Johnson LN, Arnold AC. Incidence of nonarteritic and arteritic anterior ischemic optic neuropathy: population-based study in the state of Missouri and Los Angeles County, California. J Neuroophthalmol. 1994;14:38–44.

 

3. Hattenhauer MG, Leavitt JA, Hodge DO, et al. Incidence of nonarteritic anterior ischemic optic neuropathy. Am J Ophthalmol. 1997;123:103–7.

 

4. Ischemic Optic Neuropathy Decompression Trial Research Group. Optic nerve decompression surgery for nonarteritic anterior ischemic optic neuropathy (NAION) is not effective and may be harmful. JAMA. 1995;273:625–32.

 

5. MacMichael IM, Cullen JF. Pathology of ischaemic optic neuropathy. In: Cant JS, ed. The optic nerve. Proceedings of the Second William MacKenzie Memorial Symposium. London: Henry Kimpton; 1972:108–16.

 

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14. Hayreh SS, Podhajsky PA, Zimmerman P. Ocular manifestations of giant cell arteritis. Am J Ophthalmol. 1998;125:509–20.

 

15. Beck RW, Servais GE, Hayreh SS. Anterior ischemic optic neuropathy. IX. Cup-to-disc ratio and its role in pathogenesis. Ophthalmology. 1987;94:1503–8.

 

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17. Yee RD, Selky AK, Purvin VA. Outcomes of optic nerve sheath decompression for nonarteritic ischemic optic neuropathy. J Neuroophthalmol. 1994;14:70–6.

 

18. Beck RW, Hayreh SS, Podhajsky PA, et al. Aspirin therapy in nonarteritic anterior ischemic optic neuropathy. Am J Ophthalmol. 1997;123:212–7.

 

19. Keltner JL. Giant cell arteritis. Signs and symptoms. Ophthalmology. 1982; 89:1101–10.

 

20. Hayreh SS, Podhajksy PA, Raman R, et al. Giant cell arteritis: validity and reliability of various diagnostic criteria. Am J Ophthalmol. 1997;123:285–96.

 

21. Boyev LR, Miller NR, Gree WR. Efficacy of unilateral versus bilateral temporal artery biopsies for the diagnosis of giant cell arteritis. Am J Ophthalmol. 1999;128:211–5.

 

22. Ischemic Optic Neuropathy Decompression Trial Research Group. Characteristics of patients with nonarteritic anterior ischemic optic neuropathy eligible for the Ischemic Optic Neuropathy Decompression Trial. Arch Ophthalmol. 1996; 114:1366–74.

 

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One comment on “Chapter 191 – Ischemic Optic Neuropathy, Diabetic Papillopathy, and Papillophlebitis

  1. The conjunctiva and cornea. Survey of Ophthalmology,. The acquired lesions are further subdivided based on origin of the mass into surface epithelial..thanks for your post..

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