Von Hippel-Lindau disease: clinical considerations and the use of fluorescein-potentiated argon laser therapy for treatment of retinal angiomas

Retinal Diseases Regulated by Hypoxia-Basic and Clinical Perspectives: A Comprehensive Review

In recent years, the number of patients with age-related macular degeneration (AMD) is increasing worldwide along with increased life expectancy. Currently, the standard treatment for wet-AMD is intravitreal injection of anti-vascular endothelial growth factor (VEGF) drugs. The upstream of VEGF is hypoxia-inducible factor (HIF), a master regulator of hypoxia-responsive genes responsive to acute and chronic hypoxia. HIF activation induces various pathological pro-angiogenic gene expressions including VEGF under retinal hypoxia, ultimately leading to the development of ocular ischemic neovascular diseases. In this regard, HIF is considered as a promising therapeutic target in ocular ischemic diseases. In clinical ophthalmology, abnormal hypofluorescent areas have been detected in the late-phase of indocyanine green angiography, which are thought to be lipid deposits at the level of Bruch’s membrane to choriocapillaris in vitreoretinal diseases. These deposits may interfere with the oxygen and nutrients that should be supplied to the retinal pigment epithelium, and that HIF/VEGF is highly suspected to be expressed in the hypoxic retinal pigment epithelium, leading to neovascularization. In this review, we comprehensively summarize pathophysiology of AMD-related ocular diseases with the HIF/VEGF pathway from basic and clinic researches with recent findings.

Current concepts on ocular vascular abnormalities in the phakomatoses

BACKGROUND

Neurofibromatosis, Von Hippel Lindau disease, and tuberous sclerosis complex are classified under the term phakomatoses. They are characterized by ocular vascular abnormalities such as vascular tortuosity, corkscrew retinal vessel configuration, moyamoya-like aspect, microaneurysms, hemangioblastomas, and focal sheathing of retinal arteries, possibly due to abnormal formation, migration, and differentiation of neural crest cells. These alterations can be the first sign or the hallmark of disease and can be related to vasoproliferative tumors.

PURPOSE

Novel imaging technologies in ophthalmology, such as near-infrared reflectances and spectral domain optical coherence tomography, have improved our knowledge in the diagnosis of these pathologies. Previously undetected macular vascular alterations have been reported in phakomatoses using optical coherence tomography angiography. This review will summarize the ophthalmic vascular abnormalities and novel imaging methods in the phakomatoses.

CONCLUSION

Active research is being led into the ophthalmic management of these conditions and their complications, and owing to elevated vascular endothelial growth factor production from hemangioblastoma, hamartoma, and retinal vascular proliferative tumors, increasing interest in this line of therapy has been conducted although research is still ongoing in this area.

Von Hippel-Lindau Disease and the Eye

Retinal hemangioblastoma (also referred to as retinal capillary hemangioma) is a benign lesion originating from the endothelial and glial components of the neurosensory retina and optic nerve head. Historically known as a manifestation of the von Hippel-Lindau (VHL) disease, it can be seen as an isolated finding or in association with some rare ocular conditions. In addition to characteristic ophthalmoscopic features, results of numerous ancillary tests including angiography, ultrasound, optical coherence tomography, and genetic tests may support the diagnosis and differentiate it from similar conditions. Because of serious life-threatening complications of VHL disease, every ocular approach to retinal hemangioblastomas should be in relationship with additional multidisciplinary diagnostic and therapeutic efforts. In addition, any patient with actual or probable diagnosis of VHL disease should be screened for ocular involvement. Unfavorable visual loss can occur early, and ocular complications of VHL range from exudative retinopathy to tractional retinal detachment, neovascular glaucoma, and phthisis bulbi. Accordingly, various treatment methods have been tested with overall acceptable responses, including photocoagulation, cryotherapy, photodynamic therapy, plaque radiotherapy, vitrectomy, and more novel intravitreal injections of anti-vascular endothelial growth factors and propranolol.

MANAGEMENT OF RETINAL HEMANGIOBLASTOMA IN VON HIPPEL-LINDAU DISEASE

PURPOSE

To review the current state of diagnosis and management of retinal hemangioblastoma and retinal vascular proliferation arising from von Hippel-Lindau (VHL) disease.

METHODS

A review of the literature was performed. Consensus was reached among authors regarding current practice, with reference to published data where possible.

RESULTS

von Hippel-Lindau disease and its ocular manifestations are relatively rare, and there is limited evidence in the literature on which to base management. There was consensus on core principles, including 1) recognition and diagnosis of von Hippel-Lindau disease when present, with appropriate referral for care of this potentially lethal systemic condition; 2) regular ophthalmic evaluation for individuals with von Hippel-Lindau disease, to identify and offer timely treatment for new or active retinal hemangioblastomas; 3) ablative treatment of retinal hemangioblastomas that can be safely destroyed, to lower risk of vision loss; 4) observation or consideration of nonablative treatments for retinal hemangioblastomas that cannot be safely destroyed; and 5) observation of asymptomatic retinal vascular proliferation, with consideration of vitrectomy for lesions exerting effects on vision.

CONCLUSION

Ocular outcomes can be gratifying in many cases with appropriate management. Improved understanding of the molecular basis for the disease creates an opportunity for rational design of better therapies.

SPONTANEOUS RESOLUTION OF MACULAR EPIRETINAL MEMBRANES AFTER FLUORESCEIN POTENTIATED ARGON LASER TREATMENT OF VON HIPPEL-LINDAU ASSOCIATED RETINAL HEMANGIOMAS: CASE REPORT AND REVIEW OF LITERATURE

PURPOSE

To illustrate spontaneous resolution of macular epiretinal membranes and inactivation of retinal hemangioma exudation after fluorescein potentiated argon laser treatment of bilateral capillary hemangiomas in a patient with a de novo heterozygous deletion in Exon 2 of the von Hippel-Lindau gene.

METHODS

Interventional case report.

RESULTS

A 23-year-old man with subjective complaints of blurry vision, photophobia, and glare. On presentation, visual acuity was 20/20 in the right eye and 20/25 in the left eye with metamorphopsia. On the basis of bilateral retinal hemangiomas on clinical examination and characterization with multimodal imaging, a diagnosis of von Hippel-Lindau disease was made. Genetic testing identified a de novo, disease-causing heterozygous deletion in Exon 2 of the von Hippel-Lindau gene. The patient underwent 4 sessions of fluorescein potentiated 532 nm argon green laser treatment directed at retinal hemangiomas. No adverse sequelae of laser treatment were noted. Seven months after the initial presentation, the patient's vision was 20/20 in both eyes with interval resolution of metamorphopsia. There was spontaneous resolution of a macular epiretinal membrane with normalization of the macular retinal microstructure. The retinal hemangiomas in both eyes appeared inactive, and no new lesions were noted.

CONCLUSION

Fluorescein potentiated argon laser successfully treated bilateral retinal hemangiomas in our patient with von Hippel-Lindau disease. Additional studies to characterize the full clinical potential of fluorescein potentiated argon laser therapy may be warranted.

Verteporfin photodynamic therapy for the treatment of sporadic retinal capillary haemangioblastoma

PURPOSE

To assess the effectivity of photodynamic therapy (PDT) for the treatment of retinal capillary haemangiomas

METHOD

Retrospective case note analysis of all patients with retinal angiomas treated with PDT between 2003 and 2010.

RESULTS

Six eyes of 6 patients (3 male, 3 female) with a mean age of 50 years (range, 23-78) were identified in our database. The follow up period was between 24 and 60 months (mean, 36). Tumor regression was evident in two patients; three tumors showed no demonstrable response to treatment on ophthalmoscopy or ultrasonography and one tumor progressed despite PDT and subsequent cryotherapy. One patient developed retinal neovascularisations following a period of inattendence to our clinic. Visual acuity improved in two patients following PDT, deteriorated in three patients and remained stable in a one patient.

CONCLUSION

The response of retinal haemangioblastomas to PDT is inconsistent. Other treatment modalities ought to be utilized for peripheral lesions, however PDT may be tried in juxtapapillary lesions where radiotherapy or cryotherapy is likely to result in concurrent visual loss.

A novel RPGR exon ORF15 mutation in a family with X-linked retinitis pigmentosa and Coats'-like exudative vasculopathy

PURPOSE

To describe the ophthalmic and genetic findings in a family with X-linked retinitis pigmentosa (RP) and Coats'-like exudative vasculopathy.

DESIGN

Observational case series.

METHODS

Family members underwent comprehensive ophthalmologic examination. Leukocyte genomic DNA samples were obtained and screened for RPGR (RP3) mutations by direct polymerase chain reaction sequencing.

RESULTS

The proband had RP with bilateral Coats'-like vasculopathy and was treated with fluorescein-potentiated argon laser therapy. The findings in two other affected male patients and three obligate carrier female patients were within the clinical spectrum of a typical X-linked-recessive RP. A novel nonsense RPGR exon ORF15 mutation (912G>T) was found to segregate with RP in this family.

CONCLUSIONS

This report expands the clinical heterogeneity spectrum caused by RPGR mutations and our knowledge concerning the molecular pathologic condition that pertains to Coats'-like RP. Consistent with the literature, Coats' response was not observed in all family members who were affected by RP, which suggests the involvement of other genetic and/or environmental factors.

Salvage external beam radiotherapy of retinal capillary hemangiomas secondary to von Hippel-Lindau disease: visual and anatomic outcomes

OBJECTIVE

To examine the visual and anatomic outcomes of patients with retinal capillary hemangiomas secondary to von Hippel-Lindau (VHL) disease treated with globe-salvaging fractionated external beam radiotherapy (EBRT) after progression of hemangiomas despite initial therapy.

DESIGN

Retrospective noncomparative consecutive case series.

PARTICIPANTS

Review of medical records of 5 patients with retinal capillary hemangiomas secondary to VHL disease.

INTERVENTION

External beam radiotherapy delivered to a total dose of 2160 cGy given over 12 daily fractions.

MAIN OUTCOME MEASURES

Data on visual acuity and tumor size were collected at baseline, 1, 3, 6, and 12 months after EBRT, and at final follow-up, using echography, fundus photographs, and clinical examination.

RESULTS

Six eyes of 5 patients were treated. Mean follow-up was 28.3 months (range, 6-51). Mean baseline visual acuity was 20/70. Mean visual acuity at last follow-up was 20/45 (range, 20/25-20/60). Tumor volume reduction was 27.5 mm(3) (range, 0.9-109.6 mm(3)). Mean percentage reduction in tumor volume was 39.6% (range, 3.3%-71.1%).

CONCLUSIONS

External beam radiotherapy is a useful option in the treatment of retinal hemangiomas secondary to VHL disease that progress despite standard therapy. External beam radiotherapy leads to improvement in visual acuity, reduction in tumor volume, and stabilization of retinal detachment in most patients treated.

Fluorescein-potentiated argon laser therapy improves symptoms and appearance of corneal neovascularization

PURPOSE

To evaluate patients' self-assessment of their symptoms and cosmetic appearance after fluorescein-potentiated argon laser treatment (FPAL) for corneal inflammation associated with neovascularization. To describe the objective effects of FPAL therapy on established corneal neovascularization with secondary corneal edema and lipid keratopathy.

METHODS

Fifteen patients with corneal neovascularization resulting from various infectious and traumatic etiologies were enrolled in an open, nonrandomized pilot study. Treatment consisted of repeated sessions of intravenous fluorescein, a photosensitizer, combined with blue-green argon laser applications to abnormal corneal vessels. Patients completed a written survey to grade their symptoms and cosmetic appearance prior to treatment and at the end of the follow-up period. Objective changes in signs after FPAL treatment were described by two nonmasked ophthalmologists after slit-lamp examinations and review of serial corneal photographs.

RESULTS

Clinical symptoms of blurred vision (p <or= 0.003), photophobia (p <or= 0.03), and cosmetic appearance ( p <or= 0.02) were found to be significantly improved by the patient's subjective assessment survey. There was a trend toward pain reduction (p <or= 0.06) but no apparent reduction in tearing or foreign body sensation (p <or= ns). Objective signs of corneal edema, neovascularization, and lipid keratopathy appeared to be reduced after FPAL therapy.

CONCLUSION

FPAL therapy for corneal neovascularization, edema, and lipid keratopathy resulted in a significant reduction in symptoms and improved quality of life for 14 of 15 (93%) patients. A controlled clinical trial to confirm the reported improvement in signs observed in this pilot study should be considered.

Treatment of retinal capillary hemangioma

OBJECTIVE

To report on the methods of treatment and the visual outcome of eyes with retinal capillary hemangioma (RCH).

DESIGN

Retrospective consecutive noncomparative case series.

PARTICIPANTS

Data on 68 patients with RCH were reviewed for the methods of treatment and visual outcome.

METHODS

Statistical analysis using cumulative multinomial logistic regression (generalized estimating equations) was performed to determine significant predictors of visual outcome.

RESULTS

Among 68 patients with RCH with von Hippel-Lindau disease (n = 31) and without von Hippel-Lindau disease (n = 37), we identified 174 RCH in 86 eyes. The overall median age at diagnosis of RCH was 30.8 years (range, 2.8-73.8 years). The RCH was bilateral in 18 cases (26%), and a family history of von Hippel-Lindau disease was positive in 19 cases (28%). Twenty-nine of the tumors (17%) touched the optic disc and were classified as juxtapapillary RCH, and the remaining 145 (83%) were extrapapillary in location. Ninety-nine (58%) RCH were 1.5 mm or smaller in size. The RCH were initially managed by observation (46%), laser photocoagulation (25%), or cryotherapy (23%). Small RCH (< or =1.5 mm in size; 63 of 99; 64%) and those touching the optic disc (14 of 29; 48%) were more likely to be initially observed. Sixty-three (82%) of the 77 RCH that were initially observed remained stable for a median follow-up of 84 months. The remaining 14 progressed and were successfully controlled with laser photocoagulation or cryotherapy. Either laser photocoagulation or cryotherapy was effective as the sole method of treatment in controlling 74% (26 of 35) and 72% (28 of 39) of extrapapillary tumors, with a mean number of 1.2 and 1.1 sessions, respectively. In a multivariate model, the only variables that were significantly related to final vision of </= 20/400 were poor initial vision (P = 0.01, odds ratio [OR], 8.5; 95% confidence interval [CI], 1.7,42) and the presence of retinal/vitreous hemorrhage (P = 0.024, OR, 5.7; 95% CI, 1.3, 25.6).

CONCLUSIONS

RCH can be safely observed initially in selected cases. Laser photocoagulation and cryotherapy are the mainstays of treatment in most cases. Early detection of RCH and treatment before the onset of severe visual loss is recommended.

Lasers in ophthalmology

Laser technology continues to progress with the addition of new lasers, new delivery systems, and new applications. The introduction of lasers to veterinary ophthalmology has radically changed the level of care that we can provide to our patients. The development of the diode laser has particularly had an impact on veterinary ophthalmology. The diode's affordability, portability, and broad applications for veterinary patients have allowed laser surgery to become a routine part of veterinary ophthalmology practice. Educating the public and veterinary community in available laser techniques will generate improved ophthalmic care and provide more data on which to build future applications.

von Hippel-Lindau disease

In recent years advances have been made in the clinical and genetic aspects of von Hippel-Lindau disease (VHL). Retinal capillary hemangioma is the most common manifestation of VHL disease and, therefore, ophthalmologists are frequently involved in the care of patients with this disease. The incidence of VHL disease is approximately 1 in 40,000 live births. It is estimated that there are approximately 7000 patients with VHL disease in the USA. The inheritance of VHL disease is autosomal dominant with high penetrance. Depending on the clinical circumstances, retinal capillary hemangioma may be managed by observation, laser photocoagulation, cryotherapy, and plaque radiotherapy. Typical extraocular lesions associated with VHL disease are central nervous system hemangioma, renal cyst, renal carcinoma, pancreatic cysts and adenoma, pancreatic islet cell tumors, pheochromocytoma, endolymphatic sac tumor of the inner ear, and cystadenoma of the epididymis and the broad ligament. The life expectancy of affected individuals may be improved by early detection and treatment of varied manifestations with the use of surveillance protocols. Identification of the VHL gene on chromosome 3p25-26 has now made it possible for suspected individuals to undergo genetic testing with a high degree of accuracy. We review herein the ophthalmic manifestations and treatment of retinal capillary hemangioma and systemic findings of the VHL disease.

Juxtapapillary capillary hemangiomas. Clinical features and visual acuity outcomes

OBJECTIVE

To describe the clinical features, association with von Hippel-Lindau (VHL) disease and visual acuity outcomes of patients with a juxtapapillary capillary hemangioma.

DESIGN

Retrospective observational case series.

PARTICIPANTS

Seventy-two eyes of 68 patients identified with a juxtapapillary capillary hemangioma. Follow-up data of at least 6 months duration were available for 60 eyes.

METHODS

A retrospective chart review of patients diagnosed with a juxtapapillary capillary hemangioma examined at four medical centers.

MAIN OUTCOME MEASURES

Age at diagnosis, visual acuity (VA) at first examination and at last follow-up, tumor growth pattern and location, associated clinical features, type of treatment, association with VHL, and presence of peripheral hemangiomas were recorded for each patient.

RESULTS

On initial examination, VA was >/=20/40 in 43 of 70 eyes (61%) and was >/=20/200 in 60 eyes (86%). At an average follow-up of 5.4 years (range, 0.5-19 years), VA of >/=20/40 was achieved in 21 eyes (35%) and >/=20/200 in 33 eyes (55%). Patients with VHL had poorer initial VA (48% vs. 70% with VA >/=20/40, and 74% vs. 93% with VA >/=20/200) and final VA (26% vs. 41% with VA >/=20/40, and 39% vs. 65% with VA >/=20/200) compared with patients without VHL. Patients with VHL more commonly were seen at an earlier age (average, 20 vs. 44 years, P: < 0.001), with bilateral (17% vs. 0%), and/or peripheral (39% vs. 0%) (P: < 0.001) tumors that more often had an endophytic growth pattern (63% vs. 22%, P: = 0.001) compared with patients without VHL. Patients selected for laser treatment generally had poorer initial (52% vs. 74% with VA >/=20/40, 79% vs. 96% with VA >/=20/200) and final VAs (18% vs. 56% with VA >/=20/40, 45% vs. 67% with VA >/=20/200) compared with patients not treated with laser.

CONCLUSIONS

On long-term follow-up of patients with a juxtapapillary capillary hemangioma, the VA generally worsens. Patients with VHL and a juxtapapillary hemangioma more often present at a younger age, have tumors with an endophytic growth pattern, and have bilateral, multiple tumors. Treatment with laser photocoagulation results in variable VA outcomes.