- Email: [email protected]
Author reply
Ophthalmology Volume 118, Number 11, November 2011 particularly in relation to the risk of regional lymph node metastasis, distant metastasis, and death.2– 4 Shields et al point out that the nodular type of conjunctival melanoma, which is a subtype known for its aggressive growth and deep penetration, was a risk factor for metastatic disease and death. We wonder if the nodular melanomas included in the series may indeed have been of greater tumor thickness and depth of invasion as opposed to the other varieties such as superficial spreading. Histologic tumor thickness should be mentioned and evaluated for conjunctival tumors included in this series. Tumor location has been shown to be a significant prognostic indicator of conjunctival melanoma in several studies including the paper by Shields et al; however, we wonder how the authors may have differentiated “forniceal” from “palpebral” origin of a conjunctival melanoma since many lesions in clinical practice involve both these areas of anatomic contiguity. In our experience, there are many conjunctival melanomas that may involve palpebral, bulbar, and forniceal components. There is a need for better clarification of anatomic location considered to be the “epicenter” of a conjunctival melanoma if location is to be analyzed as a prognostic factor for metastasis and survival. We have been using the American Joint Committee on Cancer (AJCC) 7th edition criteria for designation of location for conjunctival melanomas.5 Although not perfect, this designation separates bulbar from non-bulbar melanomas. It also takes into account tumor thickness (depth of invasion) as a criterion for prognostic grouping of conjunctival melanomas. A more uniform and universal use of AJCC criteria in large-scale validation studies of conjunctival melanoma may prove useful and allow for continued improvement in classifications that aim to correlate clinical and histologic features of conjunctival melanoma with metastasis and survival and in selection of appropriate cases for additional procedures such as sentinel lymph node biopsy. To that end, the data presented in the Shields’ important paper could be revisited, reanalyzed, and perhaps classified based on AJCC criteria, and that would contribute greatly to our current knowledge of prognostic factors for conjunctival melanoma and contribute significantly to our understanding of appropriate selection criteria for sentinel lymph node biopsy for conjunctival melanoma. QASIEM NASSER, MD BITA ESMAELI, MD Houston, Texas References 1. Shields CL, Markowitz JS, Belinsky I, et al. Conjunctival melanoma outcomes based on tumor origin in 382 consecutive cases. Ophthalmology 2011;118:389 –95. 2. Paridaens AD, Minassian DC, McCartney AC, Hungerford JL. Prognostic factors in primary malignant melanoma of the conjunctiva: a clinicopathological study of 256 cases. Br J Ophthalmol 1994;78:252–9. 3. Savar A, Ross MI, Prieto VG, et al. Sentinel lymph node biopsy for ocular adnexal melanoma: experience in 30 patients. Ophthalmology 2009;116:2217–23. 4. Savar A, Esmaeli B, Ho H, et al. Conjunctival melanoma: local-regional control rates, and impact of high-risk histopathologic features. J Cutan Pathol 2011;38:18 –24.
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5. American Joint Committee on Cancer Staging Manual. 7th ed. New York, NY: Springer; 2010:50 –1.
Author reply Dear Editor: We appreciate the comments submitted by Drs. Nasser and Esmaeli. Our report1 was an extensive analysis of a large cohort of 382 patients with a rare condition (conjunctival melanoma), in which data was retrospectively collected over a 33-year period. The clinical data was relatively complete as each patient was managed by our team and clinical information was diligently recorded at each visit. The histopathology data was scantier as this was extracted from pathology reports by various pathologists over a 3decade period. The variability in pathology interpretation, tumor measurement, and invasive features precluded consistent recording of those variables. It would have been ideal to examine the histopathology slides of each case but many were not available. Conjunctival melanoma most often arises from primary acquired melanosis (PAM), and less often from nevus or de novo. The focus of this report was simply to assess if the different origins affected prognosis as it is recognized in the cutaneous literature that skin melanoma from lentigo maligna (similar to PAM) has better prognosis. Similarly, we found conjunctival melanoma from PAM with better prognosis. Nodular melanoma referred to the general topography of the tumor as nodular (versus flat), based on clinical examination. The median melanoma basal dimension was 9 mm, with melanoma arising from nevus showing smaller median size of 5 mm compared with those arising from primary acquired melanosis with larger median size of 10 mm. We agree with Nasser and Esmaeli that nodular melanoma could be more aggressive or this might simply represent larger tumor with greater tumor burden and greater risk for dissemination. We concur that the American Joint Committee on Cancer (AJCC) is a start to uniform classification of this malignancy. In the AJCC classification, melanoma location and size are important. Melanoma involving bulbar (T1), palpebral/forniceal/caruncular (T2), and deeper invasion into globe, eyelid, orbit sinus (T3), or brain (T4) show increasing risk for metastasis. We foresee that future studies on ocular malignancies could benefit from using the AJCC classification. The 7th edition AJCC was published in 2010, and our report was completed and submitted to the journal on January 1, 2010, before this new classification was available. We do believe that reassessment of this large cohort1 using the AJCC classification might provide further insight for validation of this classification scheme. In our multivariate analysis for metastasis, 4 features were found important, including tumor location, invasive features, tumor configuration, and tumor origin. The first 2 are features in the AJCC classification. The latter 2 features are not in this classification and based on their strong relationship to metastasis (P ⫽ 0.005, P ⫽ 0.001, respectively), perhaps they should be included in the next revision of the AJCC classification for conjunctival melanoma. We appreciate the insight of Drs. Nasser and Esmaeli, and hope
Letters to the Editor to be able to provide a report based on AJCC classification of conjunctival melanoma in the near future. CAROL L. SHIELDS, MD JERRY A. SHIELDS, MD Philadelphia, Pennsylvania Reference 1. Shields CL, Markowitz JS, Belinsky I, et al. Conjunctival melanoma: outcomes based on tumor origin in 382 consecutive cases. Ophthalmology 2011;118:389 –95.
IOL Power Calculation after Refractive Surgery Dear Editor: We read with great interest the paper by McCarthy et al1 concerning intraocular lens (IOL) power calculation after refractive corneal surgery published in the May 2011 issue. They undertook significant effort to perform such a study in a large number of patients, and we congratulate them. We would like to thank them because they tested, among the others, the method we previously described (R factor). Unfortunately, we found some errors in the paper. First, they included our method among those that require information from the prior laser surgery and named these methods “historical.” Unfortunately, this is not true, as our method2 does not require knowledge of the history of the patient, and to the best of our knowledge, was the first among such methods to be published, (maybe for this it could be named historical). In fact, it relies on a correcting factor (R factor) calculated with the following formula: R⫽ 0.0276*AL ⫹ 0.3635 where AL is the axial length. This factor has to be multiplied by the patient’s corneal radius, so it is clear that the history of the patient is not needed. In the methods section, they do not clarify how they calculated the R factor, and as they describe it as historical, we are afraid that they have miscalculated it leading to uncertainties in their findings and/or conclusions. According to the Table they published, it appears they utilized this correcting factor with SRKT, HofferQ, and Holladay formulas. Actually, in our first paper on this topic, we suggested using this correcting factor with either SRK T or Holladay 1 formulas, but in 2009 we published another paper,3 in which we suggested that this correcting factor should be used with SRKT in cases of eyes with an axial length (AL) ⬍30 mm but in eyes with an AL ⬎30 mm, it should be used with both SRKT and SRK II and the results should be averaged. In this way, we can avoid excessive hypercorrections in these long eyes. We are curious to know if the authors could comment on our clarifications, and we hope they can explain if our comments lead to any changes or clarifications in the authors very good work. NICOLA ROSA, MD LUIGI CAPASSO, MD MADDALENA DE BERNARDO, MD MICHELE LANZA, MD Naples, Italy References 1. McCarthy M, Gavanski GM, Paton KE, Holland SP. Intraocular lens power calculations after myopic laser refractive
surgery: a comparison of methods in 173 eyes. Ophthalmology 2011;118:940 – 4. 2. Rosa N, Capasso L, Romano A. A new method for calculating intraocular lens power after photorefractive keratectomy. J Refract Surg 2002;18:720 – 4. 3. Rosa N, Capasso L, Lanza M, Borrelli M. Clinical results of a corneal radius correcting factor in calculating intraocular lens power after corneal refractive surgery. J Refract Surg 2009;25:599 – 603.
Transmittance Curve of an IOL Dear Editor: The article of Artigas1 published in your journal caught our attention. We were surprised by the discrepancy in the transmittance curves of the Hydriol 60C and the SlimFlex (Physiol, Belgium) found by the authors that are respectively a Cloop and a 4-haptic intraocular lens (IOL) made with the same raw material; these essential data are part of the file of the Conformité Européenne (CE) mark. The accurate outcomes in this paper are that of the Hydriol 60C. The SlimFlex must have been tilted in the spectrometer. The spectrometer Lambda 800 UV/Vis (Perkin Elmer, Waltham, MA) is a very precise instrument with a polychromatic source. A monochromator disperses the spectrum and transmits a mechanically selectable narrow band of wavelengths of light from the wider range of wavelengths available at the polychromatic source. Any tilt or misalignment between the sample and the light beam induces error on the transmittance measurement as the respective alignment between elements is done for plane cells. The IOLs have a curved surface which is not compatible with spectrometers that requires quartz or polymethyl methacrylate (PMMA) cuvettes. Physiol uses material flat disks to assess the transmittance. We provide the transmittance curve of our IOL Slimflex similar to the one of Hydriol 60C (Fig 1; available at http://aaojournal.org). PAGNOULLE CHRISTOPHE, PHD BOZUKOVA DIMITRIYA, PHD GOBIN LAURE, PHD Liège, Belgium Reference 1. Artigas JM, Felipe A, Navea A, et al. Spectral transmittance of intraocular lenses under natural and artificial illumination: criteria analysis for choosing a suitable filter. Ophthalmology 2011;118:3– 8.
Author reply Dear Editor: The letter written by Pagnoulle et al1 of the company Physiol SA explains that the spectral transmission curve of their Physiol Slim Flex lens (PhysIOL SA, Liège, Belgium), measured by us and published in our article,1 may be wrong. Pagnoulle et al1 say that this curve is similar to that of their Physiol Hydriol lens, which we also measured and they state that, in this case, our determinations are indeed correct. They suggest that perhaps a slight tilt of the lens might have
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5. American Joint Committee on Cancer Staging Manual. 7th ed. New York, NY: Springer; 2010:50 –1.
Author reply Dear Editor: We appreciate the comments submitted by Drs. Nasser and Esmaeli. Our report1 was an extensive analysis of a large cohort of 382 patients with a rare condition (conjunctival melanoma), in which data was retrospectively collected over a 33-year period. The clinical data was relatively complete as each patient was managed by our team and clinical information was diligently recorded at each visit. The histopathology data was scantier as this was extracted from pathology reports by various pathologists over a 3decade period. The variability in pathology interpretation, tumor measurement, and invasive features precluded consistent recording of those variables. It would have been ideal to examine the histopathology slides of each case but many were not available. Conjunctival melanoma most often arises from primary acquired melanosis (PAM), and less often from nevus or de novo. The focus of this report was simply to assess if the different origins affected prognosis as it is recognized in the cutaneous literature that skin melanoma from lentigo maligna (similar to PAM) has better prognosis. Similarly, we found conjunctival melanoma from PAM with better prognosis. Nodular melanoma referred to the general topography of the tumor as nodular (versus flat), based on clinical examination. The median melanoma basal dimension was 9 mm, with melanoma arising from nevus showing smaller median size of 5 mm compared with those arising from primary acquired melanosis with larger median size of 10 mm. We agree with Nasser and Esmaeli that nodular melanoma could be more aggressive or this might simply represent larger tumor with greater tumor burden and greater risk for dissemination. We concur that the American Joint Committee on Cancer (AJCC) is a start to uniform classification of this malignancy. In the AJCC classification, melanoma location and size are important. Melanoma involving bulbar (T1), palpebral/forniceal/caruncular (T2), and deeper invasion into globe, eyelid, orbit sinus (T3), or brain (T4) show increasing risk for metastasis. We foresee that future studies on ocular malignancies could benefit from using the AJCC classification. The 7th edition AJCC was published in 2010, and our report was completed and submitted to the journal on January 1, 2010, before this new classification was available. We do believe that reassessment of this large cohort1 using the AJCC classification might provide further insight for validation of this classification scheme. In our multivariate analysis for metastasis, 4 features were found important, including tumor location, invasive features, tumor configuration, and tumor origin. The first 2 are features in the AJCC classification. The latter 2 features are not in this classification and based on their strong relationship to metastasis (P ⫽ 0.005, P ⫽ 0.001, respectively), perhaps they should be included in the next revision of the AJCC classification for conjunctival melanoma. We appreciate the insight of Drs. Nasser and Esmaeli, and hope
Letters to the Editor to be able to provide a report based on AJCC classification of conjunctival melanoma in the near future. CAROL L. SHIELDS, MD JERRY A. SHIELDS, MD Philadelphia, Pennsylvania Reference 1. Shields CL, Markowitz JS, Belinsky I, et al. Conjunctival melanoma: outcomes based on tumor origin in 382 consecutive cases. Ophthalmology 2011;118:389 –95.
IOL Power Calculation after Refractive Surgery Dear Editor: We read with great interest the paper by McCarthy et al1 concerning intraocular lens (IOL) power calculation after refractive corneal surgery published in the May 2011 issue. They undertook significant effort to perform such a study in a large number of patients, and we congratulate them. We would like to thank them because they tested, among the others, the method we previously described (R factor). Unfortunately, we found some errors in the paper. First, they included our method among those that require information from the prior laser surgery and named these methods “historical.” Unfortunately, this is not true, as our method2 does not require knowledge of the history of the patient, and to the best of our knowledge, was the first among such methods to be published, (maybe for this it could be named historical). In fact, it relies on a correcting factor (R factor) calculated with the following formula: R⫽ 0.0276*AL ⫹ 0.3635 where AL is the axial length. This factor has to be multiplied by the patient’s corneal radius, so it is clear that the history of the patient is not needed. In the methods section, they do not clarify how they calculated the R factor, and as they describe it as historical, we are afraid that they have miscalculated it leading to uncertainties in their findings and/or conclusions. According to the Table they published, it appears they utilized this correcting factor with SRKT, HofferQ, and Holladay formulas. Actually, in our first paper on this topic, we suggested using this correcting factor with either SRK T or Holladay 1 formulas, but in 2009 we published another paper,3 in which we suggested that this correcting factor should be used with SRKT in cases of eyes with an axial length (AL) ⬍30 mm but in eyes with an AL ⬎30 mm, it should be used with both SRKT and SRK II and the results should be averaged. In this way, we can avoid excessive hypercorrections in these long eyes. We are curious to know if the authors could comment on our clarifications, and we hope they can explain if our comments lead to any changes or clarifications in the authors very good work. NICOLA ROSA, MD LUIGI CAPASSO, MD MADDALENA DE BERNARDO, MD MICHELE LANZA, MD Naples, Italy References 1. McCarthy M, Gavanski GM, Paton KE, Holland SP. Intraocular lens power calculations after myopic laser refractive
surgery: a comparison of methods in 173 eyes. Ophthalmology 2011;118:940 – 4. 2. Rosa N, Capasso L, Romano A. A new method for calculating intraocular lens power after photorefractive keratectomy. J Refract Surg 2002;18:720 – 4. 3. Rosa N, Capasso L, Lanza M, Borrelli M. Clinical results of a corneal radius correcting factor in calculating intraocular lens power after corneal refractive surgery. J Refract Surg 2009;25:599 – 603.
Transmittance Curve of an IOL Dear Editor: The article of Artigas1 published in your journal caught our attention. We were surprised by the discrepancy in the transmittance curves of the Hydriol 60C and the SlimFlex (Physiol, Belgium) found by the authors that are respectively a Cloop and a 4-haptic intraocular lens (IOL) made with the same raw material; these essential data are part of the file of the Conformité Européenne (CE) mark. The accurate outcomes in this paper are that of the Hydriol 60C. The SlimFlex must have been tilted in the spectrometer. The spectrometer Lambda 800 UV/Vis (Perkin Elmer, Waltham, MA) is a very precise instrument with a polychromatic source. A monochromator disperses the spectrum and transmits a mechanically selectable narrow band of wavelengths of light from the wider range of wavelengths available at the polychromatic source. Any tilt or misalignment between the sample and the light beam induces error on the transmittance measurement as the respective alignment between elements is done for plane cells. The IOLs have a curved surface which is not compatible with spectrometers that requires quartz or polymethyl methacrylate (PMMA) cuvettes. Physiol uses material flat disks to assess the transmittance. We provide the transmittance curve of our IOL Slimflex similar to the one of Hydriol 60C (Fig 1; available at http://aaojournal.org). PAGNOULLE CHRISTOPHE, PHD BOZUKOVA DIMITRIYA, PHD GOBIN LAURE, PHD Liège, Belgium Reference 1. Artigas JM, Felipe A, Navea A, et al. Spectral transmittance of intraocular lenses under natural and artificial illumination: criteria analysis for choosing a suitable filter. Ophthalmology 2011;118:3– 8.
Author reply Dear Editor: The letter written by Pagnoulle et al1 of the company Physiol SA explains that the spectral transmission curve of their Physiol Slim Flex lens (PhysIOL SA, Liège, Belgium), measured by us and published in our article,1 may be wrong. Pagnoulle et al1 say that this curve is similar to that of their Physiol Hydriol lens, which we also measured and they state that, in this case, our determinations are indeed correct. They suggest that perhaps a slight tilt of the lens might have
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