Donald Coleman - Academia.edu (original) (raw)
Papers by Donald Coleman
Investigative Ophthalmology & Visual Science, 2005
Transactions. Section on Ophthalmology. American Academy of Ophthalmology and Otolaryngology
Debridement of the vitreous from perforating injuries can be more effectively and expeditiously a... more Debridement of the vitreous from perforating injuries can be more effectively and expeditiously accomplished with the aid of vitreous suction and cutting instruments than with conventional sponge-forceps technique. This technique is of great value as part of primary closure of perforating ocular injuries. In addition, trauma which results in (1) lens rupture with expulsion of the lens material into the vitreous; (2) massive vitreous hemorrhage with ciliary body laceration or posterior globe laceration; (3) retinal detachment with vitreous hemorrhage; or (4) retained reactive intraocular foreign body, requires vitrectomy. Because of inflammatory and fibroplastic changes, the earliest possible surgical intervention is recommended in these situations. Removal of lens material, reactive foreign body, or traction membranes, and early repair of retinal detachment may all be facilitated by new vitrectomy instrumentation.
Investigative ophthalmology & visual science, 1985
Human intraocular tumors and tumors derived from human tumor cell lines grown subcutaneously in t... more Human intraocular tumors and tumors derived from human tumor cell lines grown subcutaneously in the athymic nude mouse were scanned by diagnostic ultrasound. Radiofrequency scan data were converted to digital form and analyzed in the frequency domain. Characteristics of normalized power spectra were found to be significantly different among human spindle cell malignant melanomas, mixed/epithelioid malignant melanomas, metastatic carcinomas, and hemangiomas. Significant differences, as well, were found between implanted primary skin malignant melanomas and adenocarcinomas of the lung, colon, and stomach. Comparison of spectral properties of human intraocular and implanted tumors revealed that human spindle cell malignant melanomas and implanted melanomas exhibit similar characteristics. Human intraocular metastatic tumors from the lung were found to exhibit characteristics similar to those of implanted lung tumors. These results indicate that the implantation of human tumor cell line...
American Journal of Ophthalmology, 1970
American Journal of Ophthalmology, 1971
American Journal of Ophthalmology, 1978
American Journal of Ophthalmology, 1973
ABSTRACT
Ultrasound in Medicine & Biology, 1986
International Ophthalmology Clinics, 1986
Cornea, 1990
In order to study the potential use of ultrasound as a noninvasive system for altering corneal cu... more In order to study the potential use of ultrasound as a noninvasive system for altering corneal curvature, we used high-density focused ultrasound at a frequency of 4.8 MHz and 7.9 MHz to produce corneal lesions in the rabbit eye. Intensity and duration threshold exposure conditions were determined for the production of minimally visible lesions. Threshold lesions were initially apparent as discrete white opacities resulting from stromal edema and disruption. Light and scanning electron microscopy of higher-energy, suprathreshold lesions revealed more extensive disruption, including the formation of a superficial stromal depression and a larger zone of edema and disorganization surrounding each lesion. Posterior stromal lamellae, endothelium, and Descemet's membrane were intact. Healing and reepithelialization resulted in a smooth corneal surface with no residual opacification. Threshold determinations predict safe exposure levels to the cornea during insonification of other ocular structures. Selective heating of the peripheral cornea using focused ultrasound may be a useful technique for correcting astigmatism.
American Journal of Ophthalmology, 1986
Hyperthermia and radiation were used in combination to treat four patients with choroidal maligna... more Hyperthermia and radiation were used in combination to treat four patients with choroidal malignant melanoma. This technique uses ultrasonically induced hyperthermia synergistically with radiation to destroy tumor cells. The lower levels of radiation used should avoid the late vascular and inflammatory complications seen in conventional radiation therapy. Tumors were scanned by a computerized diagnostic ultrasound system before treatment and assigned an acoustic tissue type on the basis of a statistical comparison of their ultrasound backscatter spectrum with spectra of tumors of known pathologic status. During the follow-up period, the longest of which was 15 months, alltumors demonstrated regression patterns consistent with choroidal tumors of the same acoustic tissue types treated with conventional radiation therapy. UNTIL RECENTLY, the standard method of managing ocular melanoma has been enucIea
Documenta Ophthalmologica Proceedings Series, 1981
A computer-based ultrasound system has been designed and constructed to provide new approaches to... more A computer-based ultrasound system has been designed and constructed to provide new approaches to processing, analyzing, and displaying clinical ultrasonograms, (c.f. Lizzi, et al. 1979, 1980). Over the past year, the system has been applied in ophthalmic examinations, and it has been continually refined and expanded as clinical trials proceed.
Ultrasound in Medicine, 1975
Estimation of ocular volumes by means of B-scan sections and planimeter measurements provides uni... more Estimation of ocular volumes by means of B-scan sections and planimeter measurements provides unique information for several areas of ophthalmic management.
Investigative ophthalmology & visual science, 1999
To develop a noninvasive technique to visualize and measure blood flow in the iris and ciliary bo... more To develop a noninvasive technique to visualize and measure blood flow in the iris and ciliary body. Echo data from 50-MHz ultrasound scans of the iris and ciliary body of rabbits were digitized using a new "swept scan" modality. The method makes use of spatial oversampling to identify regions with scatterers whose range changes with time. The data allowed construction of high-resolution B-mode images with embedded flow information. Pulsatility over the cardiac cycle was evaluated by sending a series of pulses along a single line of sight containing a vessel of interest. Local blood flow and changes over the cardiac cycle before and after application of atropine were quantified. Flow was identified in the radial vessels and major arterial circle of the iris. Vessels with lumens as small as 40 microm in diameter and flow velocities as low as 0.6 mm/sec were measured. Change in blood velocity over the cardiac cycle was determined to be approximately 27%. Peak systolic veloci...
Bibliotheca ophthalmologica : supplementa ad ophthalmologica, 1975
The use of choroidal excavation and vascular pulsations in the ultrasonic diagnosis of tumors has... more The use of choroidal excavation and vascular pulsations in the ultrasonic diagnosis of tumors has been a helpful diagnostic feature. Evaluation of choroidal tumors is presently performed with A-, B- and M-scan techniques. Solid tumors of high homogeneity produce characteristic hollows or acoustic quiet zones that replace the normal choroidal pattern. M-scan patterns of vascular pulsations are also useful in demonstrating vascularity or choroidal tumors. Color displays accentuate amplitude variations in ocular tumors.
Ultrasound in Medicine, 1978
Lesions were created in the retina, choroid and sclera of the rabbit using continuous-wave, high-... more Lesions were created in the retina, choroid and sclera of the rabbit using continuous-wave, high-intensity ultrasound. In-vivo studies were performed on albino and pigmented rabbits using focussed ultrasound at 9.8 MHz. The quantitative evaluation of the effects of continuous-wave ultrasound is of interest because of the potential therapeutic applications to ocular tissues in those cases which cannot be purposely altered by optical energy.
Documenta Ophthalmologica Proceedings Series, 1981
The thickness of the posterior ocular coats of the eye (the retina, choroid, and sclera) has only... more The thickness of the posterior ocular coats of the eye (the retina, choroid, and sclera) has only been evaluable by indirect methods such as histologic examination, which allow extrapolation to the in vivo thickness. Many functional and aging processes are related to the integrity and thickness of these structures, thus the ability to provide an in vivo measurement would be valuable in studying both normal variations and disease states.
Investigative Ophthalmology & Visual Science, 2005
Transactions. Section on Ophthalmology. American Academy of Ophthalmology and Otolaryngology
Debridement of the vitreous from perforating injuries can be more effectively and expeditiously a... more Debridement of the vitreous from perforating injuries can be more effectively and expeditiously accomplished with the aid of vitreous suction and cutting instruments than with conventional sponge-forceps technique. This technique is of great value as part of primary closure of perforating ocular injuries. In addition, trauma which results in (1) lens rupture with expulsion of the lens material into the vitreous; (2) massive vitreous hemorrhage with ciliary body laceration or posterior globe laceration; (3) retinal detachment with vitreous hemorrhage; or (4) retained reactive intraocular foreign body, requires vitrectomy. Because of inflammatory and fibroplastic changes, the earliest possible surgical intervention is recommended in these situations. Removal of lens material, reactive foreign body, or traction membranes, and early repair of retinal detachment may all be facilitated by new vitrectomy instrumentation.
Investigative ophthalmology & visual science, 1985
Human intraocular tumors and tumors derived from human tumor cell lines grown subcutaneously in t... more Human intraocular tumors and tumors derived from human tumor cell lines grown subcutaneously in the athymic nude mouse were scanned by diagnostic ultrasound. Radiofrequency scan data were converted to digital form and analyzed in the frequency domain. Characteristics of normalized power spectra were found to be significantly different among human spindle cell malignant melanomas, mixed/epithelioid malignant melanomas, metastatic carcinomas, and hemangiomas. Significant differences, as well, were found between implanted primary skin malignant melanomas and adenocarcinomas of the lung, colon, and stomach. Comparison of spectral properties of human intraocular and implanted tumors revealed that human spindle cell malignant melanomas and implanted melanomas exhibit similar characteristics. Human intraocular metastatic tumors from the lung were found to exhibit characteristics similar to those of implanted lung tumors. These results indicate that the implantation of human tumor cell line...
American Journal of Ophthalmology, 1970
American Journal of Ophthalmology, 1971
American Journal of Ophthalmology, 1978
American Journal of Ophthalmology, 1973
ABSTRACT
Ultrasound in Medicine & Biology, 1986
International Ophthalmology Clinics, 1986
Cornea, 1990
In order to study the potential use of ultrasound as a noninvasive system for altering corneal cu... more In order to study the potential use of ultrasound as a noninvasive system for altering corneal curvature, we used high-density focused ultrasound at a frequency of 4.8 MHz and 7.9 MHz to produce corneal lesions in the rabbit eye. Intensity and duration threshold exposure conditions were determined for the production of minimally visible lesions. Threshold lesions were initially apparent as discrete white opacities resulting from stromal edema and disruption. Light and scanning electron microscopy of higher-energy, suprathreshold lesions revealed more extensive disruption, including the formation of a superficial stromal depression and a larger zone of edema and disorganization surrounding each lesion. Posterior stromal lamellae, endothelium, and Descemet's membrane were intact. Healing and reepithelialization resulted in a smooth corneal surface with no residual opacification. Threshold determinations predict safe exposure levels to the cornea during insonification of other ocular structures. Selective heating of the peripheral cornea using focused ultrasound may be a useful technique for correcting astigmatism.
American Journal of Ophthalmology, 1986
Hyperthermia and radiation were used in combination to treat four patients with choroidal maligna... more Hyperthermia and radiation were used in combination to treat four patients with choroidal malignant melanoma. This technique uses ultrasonically induced hyperthermia synergistically with radiation to destroy tumor cells. The lower levels of radiation used should avoid the late vascular and inflammatory complications seen in conventional radiation therapy. Tumors were scanned by a computerized diagnostic ultrasound system before treatment and assigned an acoustic tissue type on the basis of a statistical comparison of their ultrasound backscatter spectrum with spectra of tumors of known pathologic status. During the follow-up period, the longest of which was 15 months, alltumors demonstrated regression patterns consistent with choroidal tumors of the same acoustic tissue types treated with conventional radiation therapy. UNTIL RECENTLY, the standard method of managing ocular melanoma has been enucIea
Documenta Ophthalmologica Proceedings Series, 1981
A computer-based ultrasound system has been designed and constructed to provide new approaches to... more A computer-based ultrasound system has been designed and constructed to provide new approaches to processing, analyzing, and displaying clinical ultrasonograms, (c.f. Lizzi, et al. 1979, 1980). Over the past year, the system has been applied in ophthalmic examinations, and it has been continually refined and expanded as clinical trials proceed.
Ultrasound in Medicine, 1975
Estimation of ocular volumes by means of B-scan sections and planimeter measurements provides uni... more Estimation of ocular volumes by means of B-scan sections and planimeter measurements provides unique information for several areas of ophthalmic management.
Investigative ophthalmology & visual science, 1999
To develop a noninvasive technique to visualize and measure blood flow in the iris and ciliary bo... more To develop a noninvasive technique to visualize and measure blood flow in the iris and ciliary body. Echo data from 50-MHz ultrasound scans of the iris and ciliary body of rabbits were digitized using a new "swept scan" modality. The method makes use of spatial oversampling to identify regions with scatterers whose range changes with time. The data allowed construction of high-resolution B-mode images with embedded flow information. Pulsatility over the cardiac cycle was evaluated by sending a series of pulses along a single line of sight containing a vessel of interest. Local blood flow and changes over the cardiac cycle before and after application of atropine were quantified. Flow was identified in the radial vessels and major arterial circle of the iris. Vessels with lumens as small as 40 microm in diameter and flow velocities as low as 0.6 mm/sec were measured. Change in blood velocity over the cardiac cycle was determined to be approximately 27%. Peak systolic veloci...
Bibliotheca ophthalmologica : supplementa ad ophthalmologica, 1975
The use of choroidal excavation and vascular pulsations in the ultrasonic diagnosis of tumors has... more The use of choroidal excavation and vascular pulsations in the ultrasonic diagnosis of tumors has been a helpful diagnostic feature. Evaluation of choroidal tumors is presently performed with A-, B- and M-scan techniques. Solid tumors of high homogeneity produce characteristic hollows or acoustic quiet zones that replace the normal choroidal pattern. M-scan patterns of vascular pulsations are also useful in demonstrating vascularity or choroidal tumors. Color displays accentuate amplitude variations in ocular tumors.
Ultrasound in Medicine, 1978
Lesions were created in the retina, choroid and sclera of the rabbit using continuous-wave, high-... more Lesions were created in the retina, choroid and sclera of the rabbit using continuous-wave, high-intensity ultrasound. In-vivo studies were performed on albino and pigmented rabbits using focussed ultrasound at 9.8 MHz. The quantitative evaluation of the effects of continuous-wave ultrasound is of interest because of the potential therapeutic applications to ocular tissues in those cases which cannot be purposely altered by optical energy.
Documenta Ophthalmologica Proceedings Series, 1981
The thickness of the posterior ocular coats of the eye (the retina, choroid, and sclera) has only... more The thickness of the posterior ocular coats of the eye (the retina, choroid, and sclera) has only been evaluable by indirect methods such as histologic examination, which allow extrapolation to the in vivo thickness. Many functional and aging processes are related to the integrity and thickness of these structures, thus the ability to provide an in vivo measurement would be valuable in studying both normal variations and disease states.