Pars plana vitrectomy for vitreous amyloidosis

Apolipoprotein AI-Derived Vitreous Amyloidosis: An Elusive Diagnosis

A 56-year-old female presented with vitreous opacity with gradual visual disturbance in her right eye of 1-year duration. A Non-Hodgkin's lymphoma had been treated 15 years before. Presenting best-corrected visual acuity (BCVA) was 20/200 in her right eye and 20/25 in her left eye. Intraocular pressure was 18 mm Hg bilaterally. Slit-lamp examination revealed no abnormal findings in the anterior segment of both eyes, including the absence of cells and flare. Fundoscopic examination indicated hazy media with the typical glass-wool-like appearance in her right eye. B-scan ultrasound demonstrated that the vitreous was full of middle-echo spots, vitreous opacities, and posterior vitreous detachment occurred. The patient underwent vitreous biopsy and a standard 25-gauge pars plana vitrectomy (diagnostic and therapeutic). Intraoperatively, the eye was noted to have severe diffuse debris and very strong vitreoretinal adhesions. Cytospin smears prepared from the vitreous aspirate indicated amorphous acellular material that stained positively with Congo Red and showed apple green birefringence on polarized microscopy, consistent with the diagnosis of amyloidosis. A genetic evaluation of tongue tissue demonstrated apolipoprotein AI-derived amyloidosis. The BCVA was 20/25 OU at 3 months postoperatively.

Vitreous amyloidosis as primary manifestation of disease: case report

A 35-year-old woman with progressive decrease of vision in both eyes and with no other associated symptoms, manifested as the only antecedent, the death of her brother due to amyloidosis. The visual acuity was counting fingers at 30 centimetres in the right eye and 20/70 in the left eye. In ophthalmoscopy of the right eye, a white, homogeneous vitreous, that was difficult to assess in detail, was observed, and in the left eye a whitish vitreous with band-like opacities in the cortical region. Vitrectomy was performed in the right eye, and a study with specific stains showed positive for amyloid material. A case is reported of amyloidosis diagnosed with specific stains in a vitreous sample for which the initial and only manifestation was the presence of vitreous opacities. The processing of these samples should be considered in patients with family history, early vitreous opacities, negative results of systemic biopsy, or atypical course of the disease.

Small gauge vitrectomy for vitreous amyloidosis and subsequent management of secondary glaucoma in patients with hereditary transthyretin amyloidosis

We conducted a retrospective observational study including 31 eyes of 20 patients in order to investigate the efficacy of 25-gauge vitrectomy for vitreous opacity with minimal conjunctival invasion and subsequent management of intraocular pressure (IOP) secondary to hereditary transthyretin amyloidosis. We followed up these patients for an average of 44.7 ± 32.6 months. The primary outcome was best corrected visual acuity (BCVA) at 1 month after surgery and at the final follow-up visit, with management of subsequent IOP elevation. Secondary outcomes included the post-vitrectomy IOP survival rate, to determine the frequency of IOP elevation requiring glaucoma surgery. Mean age at vitrectomy was 55.4 ± 9.1 years. Logarithm of the Minimum Angle of Resolution (LogMAR) BCVA showed immediate improvement from 0.73 ± 0.62 to 0.00 ± 0.22 at 1 month (p = 4.1 × 10⁻⁷), an improvement that was maintained up to the final follow-up visit, when IOP was maintained at 13.1 ± 5.2 mmHg. The survival rate of post-vitrectomy IOP control was 0.51, 0.38, and 0.23 at 12, 24, and 60 months, respectively. A poor post-vitrectomy IOP survival rate suggests that removing vitreous amyloid via 25-gauge vitrectomy is not sufficient to guarantee good visual function; subsequent careful follow-up and proper glaucoma management is also required in order to achieve this goal.

Nd:YAG capsulotomy for the management of posterior capsular amyloidosis

Purpose

To describe the accumulation of amyloid in Berger's space.

Observations

A 35-year-old man with autosomal-dominant, familial transthyretin-associated amyloidosis and bilateral vitreous opacities had a recurrence of amyloidosis following vitrectomy. The recurrent amyloid was attached to the posterior capsule of the lens. Phacoemulsification followed by neodymium:yttrium-aluminum-garnet (Nd:YAG) capsulotomy was helpful in restoring vision.

Conclusions and importance

Amyloid can reaccumulate in Berger's space, which is difficult to reach in phakic eyes during vitrectomy and can then cause decreased vision. Recognition of this interesting anatomic problem will allow for faster visual rehabilitation of the patient.

Ocular Manifestations of Familial Transthyretin Amyloidosis

PURPOSE

Among patients with familial amyloidosis, mutation in the transthyretin (TTR) protein is the most common type. Patients with TTR amyloidosis have been noted to have ocular, especially vitreous, involvement. In this report, an analysis of the types and frequency of ocular manifestations in TTR amyloidosis is presented.

DESIGN

Observational case series.

METHODS

Two hundred and sixty-three patients who presented to Mayo Clinic with TTR amyloidosis between January 1, 1970, and November 1, 2014, consented to be included in the Mayo Clinic amyloidosis database maintained by the Department of Hematology. Fifty-four patients had ocular examinations at a mean of 4.25 ± 3.93 months after systemic symptoms.

RESULTS

Of 108 examined eyes in 54 patients with TTR amyloidosis, there were 26 eyes (24%) in 13 patients with ocular involvement. Patients with ocular involvement were more likely to be women than those without ocular involvement (46% vs 15%, respectively, P = .008) and have significantly worse visual acuity (VA) at presentation (logMAR 0.24 [Snellen equivalent 20/30] vs logMAR 0.00 [Snellen equivalent 20/20], P = .017). The ophthalmic findings included vitreous amyloid (26/26, 100%), neurotrophic keratitis (2/26, 8%), glaucoma (5/26, 19%), and tortuous retinal vessels (4/26, 15%). The glaucoma was classified as open-angle (2/26), exfoliative (2/26), and neovascular following central retinal vein occlusion from amyloidosis (1/26). Ten patients underwent vitrectomy for visually significant vitreous amyloidosis, which significantly improved VA from a baseline of logMAR 0.70 (Snellen equivalent 20/100) to logMAR 0.05 (Snellen equivalent ∼20/20), P = .003. Three TTR mutations, Glu89Lys, Gly47Arg, and homozygous Gly6Ser, not previously described, were associated with vitreous amyloid.

CONCLUSION

In this large cohort of patients with TTR amyloidosis, female sex and decreased VA were associated with ocular amyloid. Three mutations that have not been previously reported to have vitreous involvement were described: Glu89Lys, Gly47Arg, and homozygous Gly6Ser.

De novo intraocular amyloid deposition after hepatic transplantation in familial amyloidotic polyneuropathy

The familiar amyloid polyneuropathy (FAP) is a rare autosomal-dominant systemic amyloidosis. Amyloid deposition occurs more frequently and extensively in the vitq. The increase in intraocular pressure (IOP) is a result of deposition of transthyretin (TTR) in trabecular meshwork. Rarely, the amyloid deposition in anterior segment can be more exuberant than in posterior segment. A 42 years old man, with FAP (Val30Met mutation), liver transplantation in 1997. He was asymptomatic, without any significant ocular abnormality until 2011. In 2011 he had an episode of pain in right eye (RE). Scalloped pupils, pupillary amyloid deposits and subtle vitreous opacities were detected. The IOP was 40 mmHg in RE and 28 mmHg in left eye (LE) with open angle. Optical coherence tomography detected a temporal superior retinal nerve fiber layer defect in LE and perimetry was normal. Topical timolol was initiated, and brimonidine was subsequently added to improve IOP control, which was achieved with topical medication until last evaluation. No progression occurred since 2011. Actually, with longer life expectancies, there is an increased risk of ocular involvement in FAP, even after liver transplantation. Although rare, a more exuberant amyloid deposition in anterior segment vs posterior segment can occur, and supports an important role of amyloid production in ciliary pigment epithelium in these patients. Medical control of IOP and a stable course are unusual in this secondary glaucoma. Ophthalmologists have an important task in the follow-up of patients and early diagnosis of risk factors for secondary glaucoma, such as scalloped pupils with amyloid deposits.

Vitreous Amyloidosis: Ocular, Systemic, and Genetic Insights

PURPOSE

To report the unique clinical and surgical characteristics encountered in eyes with vitreous amyloidosis. Systemic evaluation and visual outcome after vitrectomy are discussed. A novel mutation in the transthyretin gene (TTR) in Indian patients with familial amyloid polyneuropathy (FAP) is described.

DESIGN

Retrospective, observational study.

PARTICIPANTS

Ten eyes of 5 patients from 2 pedigrees with a diagnosis of vitreous amyloidosis.

METHODS

Detailed history, pedigree charting, systemic and ocular examination of 10 eyes (5 patients from 2 pedigrees) were carried out. Tests were performed to rule out vitreitis, retinal vasculitis, vitreous hemorrhage, and systemic amyloidosis. Genetic analysis to identify the mutation was performed in 1 patient. Vitreous biopsy, followed by 25-gauge pars plana vitrectomy, was performed in the same sitting in all cases. Samples were sent for Congo red staining and polarized microscopy. Patients were followed up on days 1, 7, and 28 and then every 2 months. Visual acuity assessment, intraocular pressure measurement, and fundus examination were performed each time.

MAIN OUTCOME MEASURES

Mutations in TTR and postoperative visual acuity.

RESULTS

Mean age at presentation was 32 years, with a 3:2 male-to-female distribution. Family history was positive in all patients. Nine eyes had pseudopodia lentis, whereas all 10 had glass wool-like vitreous. Glaucoma developed in 1 patient (2 eyes). Waxy paper-like vitreous with firm vitreous adhesions beyond major arcades and along retinal vessels was noted during surgery in all eyes. Congo red staining and apple green birefringence demonstrated vitreous amyloidosis. The mean preoperative best-corrected visual acuity (BCVA) was 1.39±0.64 logarithm of the minimum angle of resolution (logMAR), whereas the postoperative BCVA improved to 0.17±0.07 logMAR (P = 0.004). Gene sequencing revealed a phenylalanine→isoleucine mutation in the 33rd position of exon 2 of TTR in 1 patient of 1 pedigree, confirming the diagnosis of FAP. Two patients subsequently were found to have sensorimotor autonomic neuropathy, whereas 2 others had subclinical autonomic dysfunction.

CONCLUSIONS

The clinical clues, management strategy, surgical characteristics, vitrectomy outcomes, and significance of systemic evaluation in vitreous amyloidosis are highlighted. A novel single mutation (Phe33Ile) in a case of FAP with vitreous amyloidosis from India is reported.

Elderly onset vitreous opacities as the initial manifestation in hereditary transthyretin (ATTR Val30Met) carries

Familial amyloid polyneuropathy (FAP) is a systemic disorder transmitted as an autosomal dominant trait and is characterized by deposits of protein fibrils in various organs leading to physiologic dysfunction. In cases with FAP in Japanese endemic foci, their signs and symptoms often develop before the age of 40 years. We report on two elderly patients (an 80-year-old woman and an 83-year-old man) with progressive vitreous opacities (VOs) as the initial manifestation of hereditary transthyretin (ATTR Val30Met) carries, who had no evidence of systemic involvement or family history of amyloidosis and lived in non-endemic areas. Therapeutic vitrectomy with extensive vitreous removal combined with cataract surgery was performed. Clinicians should consider the possibility of hereditary transthyretin carries in cases presenting with VOs of undetermined etiology to avoid misdiagnosis.

In vivo imaging of cortical vitreous using 1050-nm swept-source deep range imaging optical coherence tomography

PURPOSE

To image the cortical vitreous, determine the prevalence of the bursa premacularis and space of Martegiani, and measure the dimensions of the bursa using the new 1050-nm swept-source deep range imaging optical coherence tomography (DRI OCT-1 Atlantis).

DESIGN

Retrospective cross-sectional study.

METHODS

One hundred and nineteen consecutive patients (5-100 years) underwent an OCT scan using 1050-nm swept-source deep range imaging optical coherence tomography. Prevalence of the bursa premacularis and space of Martegiani and the stage of posterior vitreous detachment (PVD) were determined. The horizontal (width) and anteroposterior (depth) dimensions of the bursa were recorded along with the patient's age.

RESULTS

A bursa was detected in 57.1% (136/238) of eyes. The bursa and space of Martegiani coexisted in 97.8% of eyes. Prevalence of detected bursa was 84.5% in eyes with either no PVD or perifoveal PVD only; the prevalence fell with further increases in the extent of PVD. Prevalence of detected bursa was 75.4% in patient group aged 0-60 years and 38% in the group aged 60-100 years. Mean width was 7001 μm (range: 3354-10 316 μm, SD: 1412 μm). Mean depth was 416 μm (range: 31-1189 μm, SD: 187 μm). Width and depth of the bursa did not correlate with age (R(2) width = 0.0316; R(2) depth = 0.0108). Bilateral bursa tended to be symmetrical in width but less so in depth (R(2) width = 0.63, P < .001; R(2) depth = 0.33, P < .001).

CONCLUSION

Swept-source OCT has allowed us to demonstrate the almost invariable coexistence of the bursa premacularis and space of Martegiani. Swept-source OCT can image both in patients from as early as the first to as late as the tenth decade of life.

Multimodal retinal imaging in a Chinese kindred with familial amyloid polyneuropathy secondary to transthyretin Ile107Met mutation

OBJECTIVE

To investigate the ocular phenotype and gene mutation of a Chinese pedigree with familial amyloid polyneuropathy (FAP) and vitreous amyloidosis.

METHODS

A Chinese pedigree with familial amyloid polyneuropathy and vitreous amyloidosis was recruited. Combined phacoemulsification, vitrectomy and intraocular lens implantation were performed on the right eye of the index patient. Ophthalmic investigations were performed before and after surgery. The DNA from the pedigree was sequenced for the transthyretin (TTR) gene.

RESULTS

After vitrectomy, the best-corrected visual acuity of the patient improved from counting finger to 20/20. Red-free confocal ophthalmoscopy demonstrated perifoveal ring and several perivessel white sheaths. Optical coherence tomography (OCT) revealed cotton wool like reflections on the vitreoretinal interface. Electroretinogram and autofluorescence was normal. Amyloid was present in the vitreous specimen. A substitution of T to G at nucleotide 381 in exon 4 of TTR DNA (Ile107Met) was found. This mutation co-segregated with phenotype in the pedigree and was not detected in 200 controls.

CONCLUSIONS

TTR Ile107Met mutation is associated with vitreous amyloidosis and FAP. OCT and red-free imaging are helpful in identifying amyloid deposits in the retina.

Bilateral optic neuropathy in a patient with familial amyloidotic polyneuropathy

Amyloidogenic transthyretin (ATTR)-related familial amyloidotic polyneuropathy (FAP) is an autosomal-dominant hereditary disease characterised by slowly progressive peripheral sensorimotor and autonomic neuropathy and tissue involvement of the heart, kidneys and central nervous system. Secondary glaucoma has been reported following intraocular surgery, but optic nerve involvement unrelated to glaucoma has not previously been described. We reported a male patient in his late 40s when deceased, who previously had a liver transplant in order to reduce the abnormal protein synthesis underlying his FAP ATTR Val30Met mutation. After 11 years of ophthalmic follow-up best-corrected visual acuity was 20/100 in his seeing eye, which further had visual field findings suggestive of optic neuropathy. This was also the diagnosis underlying the preceding insidious full loss of vision in the fellow eye, with colour Doppler imaging to support an ischaemic aetiology. To our knowledge, this is the first report of ischaemic optic neuropathy in this familial amyloid disorder.

Vitreous surgery impact in glaucoma development in liver transplanted familial amyloidosis ATTR V30M Portuguese patients

PURPOSE

Familial amyloidosis with polyneuropathy (FAP) sometimes courses with vitreous amyloid. The aim of this study was to evaluate the incidence of glaucoma after vitrectomy in FAP patients.

METHODS

A total of 79 eyes of 42 liver transplanted FAP patients and 16 eyes of 16 non-FAP patients with rhegmatogenous retina detachment were collected. The patients were divided in to three groups: Group I - FAP patients with vitreous opacities submitted to vitrectomy, Group II - FAP patients without vitreous opacities and not submitted to vitrectomy and, Group III - non-FAP patients with rhegmatogenous retinal detachment submitted to vitrectomy. The Group I was subdivided into: Ia - "complete" vitrectomy; Ib - "incomplete" vitrectomy. The onset of glaucoma was considered when the intraocular pressure level was higher than 21 mmHg, with concomitant visual field abnormalities and optic nerve cupping.

RESULTS

Post vitrectomy glaucoma was more frequent in Group I (56.1%) than in Group III (12.5%) and in Group II (10.5%). We observed a higher incidence of glaucoma in the Ia than in the Ib subgroup (86.4 vs. 21.1%) and earlier appearance in subgroup Ia (7.9 ± 3.6 vs. 39.5 ± 6.6 months).

CONCLUSION

Vitrectomy induced the development of glaucoma in FAP patients.

Recurrence of vitreous amyloidosis and need of surgical reintervention in Portuguese patients with familial amyloidosis ATTR V30M

PURPOSE

Vitreous amyloid deposits are one of the most common ocular manifestations of familial amyloidosis ATTR V30M (FAP-I), which can be the only manifestation of the disease and can appear even after liver transplantation. Removal by vitrectomy is usually performed, but vitreous amyloid recurrence has been frequently reported. This study was undertaken to evaluate the recurrence of vitreous amyloidosis and its relationship with the degree of previous vitreous removal.

METHODS

Fifty-four vitrectomized eyes from 32 patients with FAP-I were evaluated in the course of a follow-up period of 30.7 ± 17.2 months (range, 8-78; median = 30 months). An extensive, as possible, vitrectomy with indentation was performed in 41 eyes (complete), and in the others 13 eyes only a vitrectomy without indentation (incomplete) was performed. The parameters evaluated were the incidence of amyloid deposits and visual outcomes.

RESULTS

A noteworthy visual acuity gain was observed, although a few patients had a subsequent decrease of visual acuity related to new vitreous amyloid deposition in the visual axis. These new amyloid deposits did not occur in eyes that had undergone extensive vitreous removal, but only in nonextensive vitrectomized eyes (P < 0.001).

CONCLUSION

Recurrence of amyloid deposition only occurred in nonextensive vitrectomized eyes and represents a false recurrence associated with incomplete vitrectomy.

Transthyretin Arg-83 mutation in vitreous amyloidosis

Both of the patients in the report had floaters and progressive vision loss for years. Two cases of familial vitreous amyloidosis occurred in three generations with typical white fibrilar opacities in the vitreous body. Pars plana vitrectomy was performed in the two patients. The vitreous specimens were subjected to histopathological examination. The specimens showed typical microscopic features of amyloidosis with Congo red stain and non-branching fibrils were seen randomly distributed with 5-10nm in diameter on a transmission electron microscope. All of the exons of the transthyretin gene were amplified with DNA isolated from the peripheral blood cells. Bi-directional sequencing of the transthyretin gene revealed a single base-pair substitution, which results in an amino acid substitution at position83, glycine to arginine (transthyretin Arg-83).

Vitrectomy for vitreous amyloidosis

AIM

To study the clinical features of vitreous amyloidosis and the effect of vitrectomy for it.

METHODS

We treated 6 eyes (4 Patients) with vitreous amyloidosis from 2008 to 2009, and followed up for 18-30 months after vitrectomy.

RESULTS

The visual acuity ranged from counting fingers to 3/50 before surgery and 15/50-40/50 after vitrectomy. No severe complication was observed.

CONCLUSION

Vitrectomy is an effective and safe treatment for eyes with vitreous amyloidosis. A long period of follow-up after surgery should be performed.

Needle-shaped deposits on retinal surface in a case of ocular amyloidosis

PURPOSE

To report a case in which optical coherence tomography (OCT) showed needle-shaped deposits on the retinal surface oriented toward the vitreous cavity and immunohistochemical findings suggested light chain-related amyloidosis.

METHODS

A 59-year-old man with no systemic complications had bilateral neovascular glaucoma and vitreous opacities in the right eye. Vitrectomy was conducted on the right eye and the excised vitreous was examined histopathologically.

RESULTS

Glass wool-like opacities were observed during vitrectomy. Postoperative fundus examination of the right eye showed retinal hemorrhage and white deposits around blood vessels and on retinal surface. Fluorescein angiography revealed hyperfluorescence of the optic disc, non-perfusion areas, and vascular focal staining. OCT depicted needle-shaped deposits perpendicular to the retinal surface oriented toward the vitreous. Histologic examination of deposits revealed positive reaction for Congo red stain, and immunohistochemical examination demonstrated positive reactivities for anti-lambda and anti-kappa light chains (precursors of amyloid protein), suggesting a diagnosis of light chain-related amyloidosis.

CONCLUSIONS

In this case, OCT showed needle-shaped deposits perpendicular to the retinal surface. Special staining with Congo red revealed the deposit to be amyloid deposition. Immunohistochemical staining suggested light chain-related amyloidosis. Vascular obstructive lesions and neovascular glaucoma secondary to retinal vascular damage in amyloidosis warrant particular attention.

Ocular manifestations in liver transplant recipients with familial amyloid polyneuropathy

PURPOSE

To evaluate postoperative ocular involvement in Swedish liver transplant (LT) recipients with familial amyloid polyneuropathy (FAP).

METHODS

Routine ophthalmological examinations were performed in 48 LT recipients, with particular attention given to amyloid deposition in the anterior segment and the vitreous body. Medical records were scrutinized for information regarding neurological impairment at the time of the LT. The diagnosis was secured in all cases by examining for amyloid deposits in biopsy specimens and positive genetic testing for amyloidogenic transthyretin (ATTR) Val30Met mutation.

RESULTS

Six patients (12.5%) developed vitreous opacities within the post-LT observation period. The first opacities were seen 40 months after transplantation, 8 years after the onset of systemic disease. Four patients (8%) developed secondary glaucoma, the first of which was observed 18 months after the procedure and 6.5 years after the onset of disease. Sixteen patients (33%) developed deposits on the anterior surface of the lens. Scalloped pupillary margins were noted in 10 patients (21%).

CONCLUSION

The prevalence of eye complications increases with time after LT and regular follow-up is necessary, especially to disclose the development of glaucoma--a complication with insidious symptoms of which patients are normally unaware.

Oculoleptomeningeal amyloidosis in a patient with a TTR Val30Gly mutation in the transthyretin gene

OBJECTIVE

To describe a patient with oculoleptomeningeal amyloidosis associated with infiltration of the vitreous, elevated intraocular pressures (IOPs), and seizures caused by a TTR Val30Gly mutation in the transthyretin gene.

DESIGN

Interventional clinicopathologic report.

PARTICIPANT

A 44-year-old man with refractory bilateral intermediate uveitis, elevated IOPs, and seizures.

INTERVENTION

The patient underwent diagnostic pars plana vitrectomy in both eyes. Intraocular and intracerebral pressures were controlled by trabeculectomy and cerebroventricular shunt placement, respectively.

MAIN OUTCOME MEASURES

Visual acuity, histopathologic analysis of vitreous and leptomeningeal tissue, genetic testing, and magnetic resonance imaging of the brain.

RESULTS

After failure of the patient to respond to topical and periocular corticosteroid therapy, a pars plana vitrectomy was performed and revealed amorphous material that showed green birefringence and dichroism on Congo red staining, establishing the diagnosis of vitreous amyloidosis. A full medical workup, including genetic testing, revealed a TTR Val30Gly mutation in the transthyretin gene. The patient subsequently developed elevated IOPs requiring bilateral trabeculectomy surgery and episodic seizures associated with leptomeningeal enhancement on magnetic resonance imaging. Histopathological analysis of a leptomeningeal biopsy taken at the time of surgery revealed amyloid infiltration, confirming the diagnosis of oculoleptomeningeal involvement by his amyloidosis. A ventriculoperitoneal shunt was placed.

CONCLUSION

Amyloidosis should be considered in patients who present with vitritis that is unresponsive to corticosteroid therapy. Vitreous biopsy with histopathological analysis is recommended in these cases. Additionally, sequencing of the transthyretin gene should be considered in patients with vitreous amyloidosis to help establish known genetic syndromes and predict both ocular and systemic comorbidities. Although not described previously, elevated IOP may develop in patients with vitreous amyloidosis due to a TTR Val30Gly mutation in the transthyretin gene.

Primary non familial amyloidosis of the vitreous and subretinal amyloid bodies

We report a case of primary non familial amyloidosis of the vitreous and subretinal amyloid bodies. Pars plana vitrectomy and subretinal numerable clusters of cystic-like glistering material were extracted. The diagnosis was confirmed only by histological findings.

Ocular amyloidosis and secondary glaucoma

OBJECTIVE

To report the clinical and histopathologic findings in two cases of secondary glaucoma associated with amyloidosis.

DESIGN

Two case reports.

METHODS

Retrospective review of clinical findings, course, and treatment of the two patients. The histopathologic findings from available biopsy material were also reviewed.

MAIN OUTCOME MEASURES

Intraocular pressure (IOP), visual field changes, and surgical outcome.

RESULTS

The first case describes a 76-year-old woman with orbital amyloidosis who developed gradual unilateral elevation of IOP that was poorly responsive to medical therapy and underwent filtration surgery. Episcleral venous pressure was elevated on the affected side, and histopathologic analysis of the conjunctival tissue confirmed perivascular amyloid deposits, further suggesting raised episcleral venous pressure to be a possible mechanism of glaucoma. The second case describes a 47-year-old white woman with familial amyloid neuropathy with a transthyretin cys-114 mutation. The association of glaucoma with this mutation has not been described previously. Persisting elevation of IOP in one eye was initially responsive to topical antiglaucoma medications but eventually required filtration surgery. Amyloid particles were found in the aqueous and on the lens surface. Histopathologic analysis of the aqueous and sclerectomy specimens demonstrated amyloid, suggesting outflow obstruction as a possible mechanism of glaucoma. Conjunctival buttonholing complicated filtration surgery in both cases, and the leaks eventually resolved with good control of IOP.

CONCLUSIONS

Amyloid associated with glaucoma may involve different pathophysiologic mechanisms. The elevated IOP may not respond well to medical therapy. Cautious surgical manipulation of the conjunctiva is warranted in these cases.

Vitreous amyloidosis in familial amyloidotic polyneuropathy. Report of a case with the Val30Met transthyretin mutation

We present a clinical pathological review of vitreous amyloidosis in a case of familial amyloidotic polyneuropathy, type I. Vitreous opacification was the first manifestation of disease in the proband, who was successfully treated with vitrectomy. The eyes were obtained at autopsy after the patient died from an unrelated cause, and the histopathology is presented here. Analysis of DNA from the pathology specimen revealed the most commonly reported transthyretin mutation, Val30Met. The classification of systemic and ocular amyloidosis as well as the genetics of familial amyloidotic polyneuropathy are briefly reviewed.

Ocular amyloidosis, with special reference to the hereditary forms with vitreous involvement

The complex of diseases referred to as amyloidosis is characterized by the deposition of amyloid substance in various tissues. The amyloid protein differs in the various forms of amyloidosis. This variation is the basis of the differences in affected tissues and subsequent clinical dissimilarities. Vitreous involvement in amyloidosis seems to be especially linked to some of the hereditary neuropathies associated with the amyloid protein transthyretin. Characterization of the amyloid proteins during recent decades has allowed a chemical and immunologic classification of amyloid fibrils. This paper presents the basis for classification of amyloidosis, reviews the literature on ocular amyloidosis, with special reference to vitreous involvement, and summarizes clinical findings and frequency of vitreous amyloid involvement in Swedish patients with familial amyloidotic polyneuropathy.

Vitreous amyloidosis without systemic or familial involvement

Vitreous amyloidosis is a rare condition that occurs in some forms of Transthyretin hereditary Amyloidosis, mainly in Familial Amyloidotic Polyneuropathy type I. Vitreous opacities may be the earliest occurring or, in some cases, only symptom of this disorder. In such cases a family history of amyloidosis is usually present. We report on a case of vitreous amyloidosis in an 80-year-old man where there is no evidence of systemic involvement and no family history of amyloidosis.

Therapy of amyloid diseases

Deposition of amyloid in the organism can lead to severe clinical symptoms and syndromes which are referred to as amyloidosis. However, amyloidosis is not a pathogenetically single disease entity. Various amyloid diseases are known which can clearly be distinguished by identifying the protein from which the amyloid is derived. Since the amyloid syndromes are pathogenetically diverse, each of the different amyloid diseases needs to be treated differently, and a type-specific amyloid therapy is mandatory. Unfortunately, an efficient therapy is not yet available for most amyloid syndromes. It is the purpose of this review to show how the different amyloid syndromes are distinguished definitively from each other and what has been successful in the effort to establish an efficient therapy of the various amyloid deposits and different amyloidoses.

A New Transthyretin Mutation Associated with Amyloidotic Vitreous Opacities

An inherited type of amyloidosis was suspected in an individual of Italian descent who presented with vitreous opacities. Although no family history of amyloidosis was apparent, the patient's transthyretin gene was examined and found not to possess any of the known transthyretin mutations. Complete DNA sequencing revealed a substitution of adenine for thymine in the second base of codon 84 causing an amino acid change of asparagine for isoleucine. The mutation was confirmed by demonstrating the loss of an Sfa N1 restriction endonuclease site. Allele-specific DNA amplification by polymerase chain reaction also was used to confirm the mutation. Either of these tests can be used for diagnosis. Asparagine 84 represents the second mutation associated with amyloidosis to occur at codon 84.

Ocular changes in familial amyloidotic polyneuropathy with dense vitreous opacities

Familial amyloid polyneuropathy (FAP) is a hereditary disease which eventually causes serious ocular problems. Seven eyes from patients with FAP 1 were vitrectomised, and the insoluble proteins from the vitreous were purified, the amyloid protein isolated, and the prealbumin characterised with a monoclonal antibody against amyloid fibril protein. Before surgery, visual acuity was very poor, due to abundant deposits in the vitreous, frequently attached to the posterior lens capsule. The pupil had peculiar indentations and the pupillary reflexes were abnormal. Intraocular pressure (IOP) was at the upper limit of normal. In the ocular fundus an intraretinal perifoveal gray ring was sometimes seen. Vitrectomy improved visual acuity, but the reappearance of vitreous deposits reduced it to 8.8/10 after 33.4 months, when treatment was needed for most of the eyes to control IOP. Amyloid and the mutant form of prealbumin characteristic of FAP 1, TTR Met 30, were shown to be present in the vitreous.