Contouring of emerging organs-at-risk (OARS) of the female pelvis and interobserver variability: A study by the Italian association of radiotherapy and clinical oncology (AIRO).

Purpose: To provide straightforward instructions for daily practice in delineating emerging organs-at-risk (OARs) of the female pelvis and to discuss the interobserver variability in a two-step multicenter study. Methods and materials: A contouring atlas with anatomical boundaries for each emerging OAR was realized by radiation oncologists and radiologists who are experts in pelvic imaging, as per their knowledge and clinical practice. These contours were identified as quality benchmarks for the analysis subsequently carried out. Radiation oncologists not involved in setting the custom-built contouring atlas and interested in the treatment of gynecological cancer were invited to participate in this 2-step trial. In the first step all participants were supplied with a selected clinical case of locally advanced cervical cancer and had to identify emerging OARs (Levator ani muscle; Puborectalis muscle; Internal anal sphincter; External anal sphincter; Bladder base and trigone; Bladder neck; Iliac Bone Marrow; Lower Pelvis Bone Marrow; Lumbosacral Bone Marrow) based on their own personal knowledge of pelvic anatomy and experience. The suggested OARs and the contouring process were then presented at a subsequent webinar meeting with a contouring laboratory. Finally, in the second step, after the webinar meeting, each participant who had joined the study but was not involved in setting the benchmark received the custom-built contouring atlas with anatomical boundaries and was requested to delineate again the OARs using the tool provided. The Dice Similarity Coefficient (DSC) and the Jaccard Similarity Coefficient (JSC) were used to evaluate the spatial overlap accuracy of the different volume delineations and compared with the benchmark; the Hausdorff distance (HD) and the mean distance to agreement (MDA) to explore the distance between contours. All the results were reported as sample mean and standard deviation (SD). Results: Fifteen radiation oncologists from different Institutions joined the study. The participants had a high agreement degree for pelvic bones sub-structures delineation according to DICE (IBM: 0.9 ± 0.02; LPBM: 0.91 ± 0.01). A moderate degree according to DICE was showed for ovaries (Right: 0.61 ± 0.16, Left: 0.72 ± 0.05), vagina (0.575 ± 0.13), bladder sub-structures (0.515 ± 0.08) and EAS (0.605 ± 0.05), whereas a low degree for the other sub-structures of the anal-rectal sphincter complex (LAM: 0.345 ± 0.07, PRM: 0.41 ± 0.10, and IAS: 0.4 ± 0.07). Conclusion: This study found a moderate to low level of agreement in the delineation of the female pelvis emerging OARs, with a high degree of variability among observers. The development of delineation tools should be encouraged to improve the routine contouring of these OARs and increase the quality and consistency of radiotherapy planning.

Transient plasma cell dyscrasia in COVID-19 patients linked to IL-6 triggering.

An unusual clonal gammopathy was reported in COVID-19 patient but whether this anomaly is related or not to the disease has not yet been clarified. To this aim, we selected a cohort of 35 COVID-19 patients swab positive and investigated serological levels of IL-6, immune response to major viral antigens and electrophoretic profile. Elevated levels of IL-6 were accompanied by a significative humoral response to viral Spike protein, revealing an altered electrophoretic profile in the gamma region. We can conclude that elevated levels of IL-6 triggers humoral response inducing a transient plasma cell dyscrasia in severe COVID-19 patients.

Spontaneous superior ophthalmic vein thrombosis: a rare entity with potentially devastating consequences.

PURPOSE: Spontaneous superior ophthalmic vein thrombosis (SOVT) is a rare entity. We describe three patients with spontaneous ophthalmic vein thrombosis, each with various risk factors. PATIENTS AND METHODS: A retrospective review of three patients with a diagnosis of superior ophthalmic vein thrombosis. Clinical characteristics, radiographic features, management techniques and outcomes are described. RESULTS: All patients presented with unilateral painful proptosis. Two patients had intact light perception, whereas one patient presented with absent light perception. All patients had identifiable risk factors for thrombosis, which included sickle cell trait, hereditary hemorrhagic telangectasia and colon cancer with recurrent deep vein thrombosis. Anticoagulation was initiated in two patients. Resolution of proptosis was seen in all patients, with no recovery of vision in one patient. CONCLUSIONS: Risk factors for spontaneous superior ophthalmic vein thrombosis are multifactorial. MRI and MRV confirm the diagnosis of SOVT. Despite urgent intervention devastating visual loss may occur.

CFTR expression and activity from the human CFTR locus in BAC vectors, with regulatory regions, isolated by a single-step procedure.

We have assembled two BAC vectors containing a single fragment spanning the entire CFTR locus and including the upstream and downstream regions. The two vectors differ in size of the upstream region, and were recovered in Escherichia coli, with intact BAC DNAs prepared for structural and functional analyses. Sequence analysis allowed precise mapping of the inserts. We show that the CFTR gene was wild type and is categorized as the most frequent haplotype in Caucasian populations, identified by the following polymorphisms: (GATT)7 in intron 6a; (TG)11T7 in intron 8; V470 at position 470. CFTR expression and activity were analyzed in model cells by RT-PCR, quantitative real-time PCR, western blotting, indirect immunofluorescence and electrophysiological methods, which show the presence of an active CFTR Cl ⁻ channel. Finally, and supporting the hypothesis that CFTR functions as a receptor for Pseudomonas aeruginosa, we show that CFTR-expressing cells internalized more bacteria than parental cells that do not express CFTR. Overall, these data demonstrate that the BAC vectors contain a functional CFTR fragment and have unique features, including derivation from a single fragment, availability of a detailed genomic map and the possibility to use standard extraction procedures for BAC DNA preparations.

The cardiovascular profile of soccer referees: an echocardiographic study.

BACKGROUND: During a soccer game, the cardiovascular system is severely taxed The referees must be alert and their level of fitness must be such that fatigue will not impair their decision-making. Referee's peak overall performance is usually after 40 when the performance starts to decline. We evaluated the morphological and functional cardiac profile of professional soccer referees. MATERIALS AND METHODS: We submitted to a clinical and echocardiographic exam a group of 120 professional soccer referees aged 25 - 45 years, including the first division of the Italian Championship, matched with 120 soccer players, including élite soccer players. Data were compared using an unpaired Student's t test. Statistical significance was with p < 0.05. RESULTS: Right ventricle dimensions (22.2 +/- 3.8 vs 25.9 +/- 2.4 mm) and Left Ventricular Mass Index (LVMi) (100.5 +/- 45.2 vs 105.4 +/- 17.3) were significantly greater in referees than in active soccer players. Left atrium dimensions (33.7 +/- 8.9 vs 36.2 +/- 3.1 mm), aortic root (29.7 +/- 7.9 vs 32.1 +/- 3 mm) and LVMi (115.1 +/- 16.7 vs 134.1 +/- 19.9 g/m2) were significantly greater in élite soccer players than in first-division referees. CONCLUSION: Our investigation shows that right ventricle is greater in referees than in soccer players. The differences (left atrium, aortic root and LVMi) between first division referees and élite soccer players may derive from the different training workloads.

Does cystic fibrosis neonatal screening detect atypical CF forms? Extended genetic characterization and 4-year clinical follow-up.

The neonatal screening protocol for cystic fibrosis (CF) is based on a first determination of blood immunoreactive trypsin (IRT1), followed by a first level genetic test that includes the 31 worldwide most common mutations of the cystic fibrosis transmembrane conductance regulator (CFTR) gene (DNA31), and a second determination of blood immunoreactive trypsin (IRT2). This approach identifies, in addition to affected subjects, a high proportion of newborns with hypertrypsinaemia at birth, in whom only one mutation is identified and who have a negative or borderline sweat test and pancreatic sufficiency. Although it has been suggested that hypertrypsinaemia may be caused by a single CFTR mutation, whether such neonates should be merely considered as healthy carriers remains a matter of debate as hypertrypsinaemia at birth may be a biochemical marker of a CFTR malfunction because of a second mild mutation. We analyzed, by means of an extended sequencing protocol, 32 newborns who tested positive at an IRT1/DNA31/IRT2 screening protocol and in whom only one CFTR mutation was found. The results obtained demonstrate that 62.5% of these newborns were also carrying a second mild CFTR mutation. The high proportion of compound heterozygous subjects, combined with the results of a 4-year follow-up in nine of these subjects all of whom displaying initial CF clinical symptoms, suggest that it may be possible to use the IRT1/DNA31/IRT2 protocol of neonatal screening to identify newborns with atypical forms of CF. In view of these findings, an extended genetic search for subjects with compound heterozygosity and a periodic clinical assessment should be considered.

Spontaneous chromosome loss and colcemid resistance in lymphocytes from patients with myotonic dystrophy type 1.

Myotonic Dystrophy type 1 (DM1) is one of the many inherited human diseases whose molecular defect is the expansion of a trinucleotide DNA sequence. DM1 shares with fragile X syndrome (FMR1), another "unstable triplet syndrome", several molecular features not present in the remaining triplet diseases. As FMR1 is also characterised by chromosome instability at the site of the expanded triplet, lymphocytes from DM1 patients and healthy donors were cultured for micronucleus (MN) analysis, in order to verify if DM1 is also prone to chromosome instability. A FISH analysis was also carried out to detect the presence of centromeric sequences in the observed MN. The data indicate that DM1 patients present a percentage of centromere-positive MN significantly higher than controls, suggesting that chromosome loss is the main mechanism underlying the origin of the increased spontaneous instability. To further assess the proneness to instability of cells of DM1 patients, cultures from patients and controls were treated in vitro with growing concentrations of two different mutagens: colcemid, a "pure" aneugen compound whose target is tubulin, and mytomicin C, a strong clastogen. The results show that the patient group is significantly less sensitive to colcemid. These data, together with FISH analysis, suggest the presence, in DM1 patients, of an already damaged tubulin, which becomes no more sensitive to the effect of colcemid and which could be the main defect underlying the aneugenic effects in DM1.

Comparison of two different protocols of neonatal screening for cystic fibrosis.

The results of two different protocols of neonatal cystic fibrosis (CF) screening in the Lazio region of Italy are reported. The first study, conducted from 1992 to 2000 on about 200,000 newborns, consisted of an immunoreactive trypsin (IRT) protocol without mutation analysis of the cystic fibrosis transmembrane conductance regulator (CFTR) gene, referred to as the IRT/IRT protocol. Approximately 5% of the newborns with a positive first IRT test were also positive at the second test; approximately 57% of the newborns with a high IRT level at the second test were subsequently found to be affected by CF. In September 1998, a second protocol that included mutation analysis (IRT/DNA/IRT protocol) was started. Comparison of the two different screening protocols in terms of sensitivity in detecting CF patients demonstrated that the IRT/DNA/IRT protocol is more effective because it is able to detect a higher number of CF patients than the IRT/IRT protocol. In the same period, in addition to the overall diagnosis performed on a screening basis, 64 other subjects were identified as being affected by CF on the basis of symptomatic findings. The overall incidence of CF (screening + symptoms) was 1 : 2982, while that for carriers was 1 : 27. The sensitivity of the screening program increased over the period from 1992 to 2000, with the enhanced sensitivity in the past 2 years being due to the introduction of the IRT/DNA/IRT protocol.

Simultaneous cycle sequencing assessment of (TG)m and Tn tract length in CFTR gene.

The lengths of the dinucleotide (TG)m and mononucleotide Tn repeats, both located at the intron 8/exon 9 splice acceptor site of the cystic fibrosis transmembrane conductance regulator (CFTR) gene whose mutations cause cysticfibrosis (CF), have been shown to influence the skipping of exon 9 in CFTR mRNA. This exon 9-skipped mRNA encodes a nonfunctional protein and is associated with various clinical manifestations in CF As a result of growing interest in these repeats, several assessment methods have been developed, most of which are, however, cumbersome, multi-step, and time consuming. Here, we describe a rapid methodfor the simultaneous assessment of the lengths of both (TG)m and Tn repeats, based on a nonradioactive cycle sequencing procedure that can be performed even without DNA extraction. This method determines the lengths of the (TG)m and Tn tracts of both alleles, which in our samples ranged from TG8 to TG12 in the presence of T5, T7, and T9 alleles, and also fully assesses the aplotypes. In addition, the repeats in the majority of these samples can be assessed by single-strand sequencing, with no need to sequence the other strand, thereby saving a considerable amount of time and effort.

Increased elastin expression in astrocytes of the lamina cribrosa in response to elevated intraocular pressure.

PURPOSE: To determine whether abnormal elastin synthesis in the glaucomatous optic nerve head and lamina cribrosa is due to elevated intraocular pressure (IOP) or secondary to axonal injury, monkeys with elevated IOP and with optic nerve transection were compared. METHODS: Unilateral, chronic elevated IOP was induced in 11 rhesus monkeys by laser scarification of the trabecular meshwork. IOP was monitored weekly and maintained within 25 to 45 mm Hg for 7 to 36 weeks. In 6 monkeys, unilateral, optic nerve transection was performed, and monkeys were killed after 4 weeks. Optic nerve damage was assessed by stereoscopic slit-lamp biomicroscopy and fundus photography and by confocal scanning laser ophthalmoscopy. The eyes were enucleated and processed for immunohistochemistry and in situ hybridization and for electron microscopic immunogold detection of elastin. Axonal loss was evaluated in cross sections of the optic nerve stained with phenylenediamine. RESULTS: Compared with normal contralateral controls, the lamina cribrosa of eyes with elevated IOP exhibited markedly increased elastin and the presence of elastotic aggregates in the extracellular matrix and upregulation of elastin mRNA in the astrocytes. In transected eyes, elastin appeared as fine fibers in the lamina cribrosa, without elastotic aggregates, and without new synthesis or abnormal deposition of elastin. At the transected site, new synthesis of elastin was present in the pia mater but not in astrocytes in the glial scar. CONCLUSIONS: This study demonstrates that abnormal elastin synthesis in experimental glaucomatous optic neuropathy in the monkey is specific to elevated IOP and not secondary to axonal loss. The mechanisms by which elevated IOP induces enhanced elastin synthesis in laminar astrocytes are unknown but differ from those involved in acute axonal injury such as transection, where inflammation and breakdown of the blood-nerve barrier occur.

Canthus-sparing ectropion repair.

PURPOSE: To describe a novel surgical technique for lower eyelid ectropion repair that avoids canthotomy and cantholysis and can be used in combination with external levator repair and/or in combination with blepharoplasty. METHODS: A retrospective analysis of lower eyelid procedures with the use of the canthus-sparing technique between January 1, 1998, and December 31, 1999, was performed. The canthus-sparing approach was used in 198 eyelid procedures for the correction of lower eyelid ectropion. Seventy-four (37.4%) procedures involved the correction of lower eyelid ectropion alone and 25 (12.6%) procedures involved the correction of lower eyelid ectropion during upper eyelid small-incision external levator repair. In these cases, an incision was made lateral to the lateral canthus and a periosteal flap was created at the lateral orbital rim. The inferior crus of the lateral canthal tendon was then attached to this full-thickness elevated periosteum. Twenty (10.1%) procedures involved the correction of ectropion during upper blepharoplasty and 79 (39.9%) procedures involved the correction of ectropion during combined upper eyelid ptosis repair and blepharoplasty. In these cases, the inferior crus of the lateral canthal tendon was attached to a periosteal flap created through the lateral portion of the blepharoplasty incision. RESULTS: The mean age of patients undergoing ectropion repair was 74.3+/-9.3 years (range, 42-93 years). The average duration of symptoms (most commonly tearing and/or ocular irritation) was 20+/-14 months (range, 3-84 months). Recurrences of lower eyelid ectropion or symptoms occurred in 4 (2%) eyelids. The average follow-up interval was 54+/-65 days (range, 3-330 days). CONCLUSIONS: The canthus-sparing approach to ectropion repair promotes a secure adhesion to the lateral orbital wall with minimal violation of normal anatomic structures and relations. It is time-efficient and reduces postoperative morbidity.

Primary and secondary transconjunctival involutional entropion repair.

PURPOSE: Lower eyelid involutional entropion is a significant disorder of the aging population resulting from horizontal eyelid laxity, overriding orbicularis oculi muscle, and attenuation of the lower eyelid retractors. The purpose of this study is to describe the long-term results of transconjunctival entropion repair. DESIGN: Interventional noncomparative case series. PARTICIPANTS: Thirty-six eyelids in 31 patients. METHODS: Charts were reviewed of all transconjunctival entropion repairs, which included myectomy, retractor fixation, and horizontal shortening performed by three oculoplastic surgeons between January 1993 and January 1999. Cases with less than 12 months follow-up were excluded. MAIN OUTCOME MEASURES: Entropion recurrence. RESULTS: Thirty-six lids in 31 patients were followed for mean of 31.5 months (12.5-79). Six of 36 lids (16.7%) had postoperative complications. Recurrent entropion occurred in 3 of 36 lids (8.3%) an average 16.3 months (7-35) after surgery. An average of 6 trichiasis lashes (1-10) occurred in 4 of 36 lids (11.1%) at a mean of 2.25 months (1-4) after surgery. There were no overcorrections. Three of 36 lids (8.3%) required additional surgery. CONCLUSIONS: Entropion recurrence after three-step transconjunctival repair is within the 0% to 30% reported recurrence for other repair techniques but more frequent than reported for a similar transcutaneous procedure. The 8.3% recurrence rate might have resulted from inadequate myectomy, inadequate retractor fixation, cicatricial changes directly related to the transconjunctival incision, or progressive involutional changes. Trichiasis was the most frequent complication. Transconjunctival entropion repair may be slightly less effective than transcutaneous repair.

Microcystic adnexal carcinoma: report of 13 cases and review of the literature.

BACKGROUND: Microcystic adnexal carcinoma (MAC) is a rare tumor of the skin. Clinically it often masquerades as a firm, subcutaneous nodule on the head and neck regions. Microscopically it extends far beyond assessed clinical margins spreading locally in the dermal, subcutaneous, and perineural tissue planes. The local recurrence rate by standard excision is about 50%. Recent preliminary reports indicate more favorable cure rates with Mohs micrographic surgery (MMS). OBJECTIVE: To present our data on 13 cases (12 patients) of MAC treated by MMS. In addition, we reviewed the medical literature to summarize the accumulated experience of MMS treatment in the management of MAC. We also present a case of bilateral MAC of the face and describe a renal transplant recipient on immunosuppressive therapy who developed MAC of the nasal bridge. METHODS: We reviewed and updated our series of MAC cases treated by MMS over the last 9 years. A total of 13 cases of MAC are reviewed. We also searched the literature for MAC treated by MMS with a follow-up of more than 2-years. RESULTS: One patient had bilateral MAC of the nose and cheek. Another patient developed a MAC of the nasal bridge 20 years after renal transplantation. In this patient predisposing factors were radiation for teenage acne and immunosuppression therapy. A total of 13 cases of MAC were treated by MMS with no recurrences, with a mean follow-up of 5.0 years (range 1.1-8.0 years). CONCLUSION: We update the medical literature with 13 MAC cases treated by MMS. To our knowledge there have been 148 cases of MAC reported in the world literature. Including our series, there have been 73 cases of MAC treated with MMS. There were only four treatment failures. Regional and/or distant metastasis from MAC is rare, with only one reported death. Following MMS, the 2-year success rate was 89.7% (35 of 39). The accumulated data continue to confirm that when MAC is discovered early and is readily accessible to excision by MMS and other subspecialty support, a favorable outcome can be expected.

Erythroid differentiation and regulatory gene expression are modulated by adenosine derivatives interfering with S-adenosylmethionine metabolic pathway.

The differentiation of murine erythroleukemia cells and the expression of SCL, Id1 and c-myc regulatory genes were studied. The first gene is a positive regulator of differentiation, while the other two are both negative regulators of differentiation and positive regulators of proliferation. Accordingly, our data show that when differentiation is stimulated SCL is upregulated while Id1 and c-myc are, coordinately, downregulated. The cultures were treated with two adenosine derivatives, 3-deazaadenosine and 3-deazaaristeromycin, known to act on the metabolic pathway of the methyl donor S-adenosylmethionin, in order to assess the possibility of a coordinated modulation, by these drugs, of regulatory gene expression and erythroid cell differentiation. 3-Deazaaristeromycin caused the simultaneous downregulation of Id1 and c-myc, whereas 3-deazaadenosine caused their upregulation; both drugs produced a transient increase in SCL expression. The use of these drugs evidenced a predominant regulatory effect of negative regulators in the control of erythroid differentiation. The distinct effects of the two drugs on regulatory gene expression led to an increased differentiation induced by 3-deazaaristeromycin and to a reduced differentiation induced by 3-deazaadenosine, if compared with controls. Southern analysis of DNA digested with methylation-specific restriction endonucleases showed that the administration of 3-deazaaristeromycin resulted in hypomethylation of SCL and c-myc, thus evidencing, in these cells, a clear correlation between DNA hypomethylation and differentiation but no straightforward correlation between DNA methylation and gene expression.

The dynamics of myogenin site-specific demethylation is strongly correlated with its expression and with muscle differentiation.

The molecular mechanisms underlying the activation of tissue-specific genes have not yet been fully clarified. We analyzed the methylation status of specific CCGG sites in the 5'-flanking region and exon 1 of myogenin gene, a very important myogenic differentiation factor. We demonstrated a loss of methylation, at the onset of C2C12 muscle cell line differentiation, limited to the CCGG site of myogenin 5'-flanking region, which was strongly correlated with the transcriptional activation of this gene and with myogenic differentiation. The same CCGG site was also found to be hypomethylated, in vivo, in embryonic mouse muscle (a myogenin-expressing tissue), as opposed to nonmuscle (nonexpressing) tissues that had a fully methylated site. In a C2C12-derived clone with enhanced myogenic ability, demethylation occurred within 2 h of induction of differentiation, suggesting the involvement of some active demethylation mechanism(s) that occur in the absence of DNA replication. Exposure to drugs that inhibit DNA methylation by acting on the S-adenosylmethionine metabolism produced a further reduction, to a few minutes, in the duration of the demethylation dynamics. These effects suggest that the final site-specific DNA methylation pattern of tissue-specific genes is defined through a continuous, relatively fast interplay between active DNA demethylation and re-methylation mechanisms.

Toxic shock syndrome originating from the foot.

The most familiar etiology of toxic shock syndrome (TSS) is that of menstruation and tampon use. Nonmenstrual TSS has been described in all types of wounds including postsurgical, respiratory infection, mucous membrane disruption, burns, and vesicular lesions caused by varicella and shingles. A case of TSS occurring in a diabetic male patient with foot blisters is presented. Early recognition by an infectious disease specialist and appropriate medical management led to complete recovery. There have been no reported cases of Staphylococcus aureus TSS originating in the foot to date.

Depressor supercilii muscle: anatomy, histology, and cosmetic implications.

PURPOSE: To describe the gross and microscopic anatomy of the depressor supercilii muscle and to discuss its cosmetic implications. METHODS: The depressor supercilii muscle was studied in detail with the use of gross anatomic dissections carried out on eight sides of four fresh cadaver heads and ten sides of five preserved cadaver heads. Histological analysis was performed on parasagittal sections of one side of a preserved cadaver head. Measurements were taken on cadaver specimens to determine the insertion point of the depressor supercilii muscle on the undersurface of the skin. RESULTS: The depressor supercilii muscle is distinct from the corrugator supercilii muscle and the medial head of the orbital portion of the orbicularis oculi muscle. The depressor supercilii muscle was noted to be superior in orientation and redder in color than the orbicularis oculi muscle. The depressor supercilii muscle arose from the frontal process of the maxilla approximately 1 cm above the medial canthal tendon and appeared to originate from two distinct heads in most specimens, a novel finding. In specimens containing two heads of the depressor supercilii muscle, the angular vessels passed between the two muscle heads. In specimens containing one muscle head, the angular vessels were found anterior to the muscle. The insertion of the depressor supercilii muscle in the dermis lay approximately 13 to 14 mm superior to the medial canthal tendon. CONCLUSIONS: The origin, insertion, and anatomy of the depressor supercilii muscle help it to act as a depressor of the eyebrow. Histologically, the depressor supercilii muscle arises distinctly from bone and has a unique insertion. The depressor supercilii muscle appears to be distinct from the corrugator supercilii and the orbicularis oculi muscles.

Protection of ganglion cells in experimental glaucoma by retinal laser photocoagulation.

OBJECTIVE: To test a hypothesis of photoreceptor involvement in retinal ganglion cell (RGC) death in chronic glaucoma. METHODS: Laser spots were applied to 6 eyes of 3 rhesus monkeys, causing focal destruction of the outer retina, including the photoreceptors. After 3 to 4 weeks, experimental glaucoma was induced in the right eyes of each monkey using argon laser trabecular destruction (ALTD). The intraocular pressures in these eyes were elevated for 3 to 7 months. As a control, 1 additional monkey underwent retinal laser photocoagulation followed by optic nerve transection instead of ALTD. Following enucleation, the retinas were embedded and sectioned for histologic evaluation. RESULTS: There was extensive loss of RGCs in the eyes with ALTD except over the large retinal laser spots, where there was an increased survival of RGCs. The RGC protection was not observed in the monkey that had undergone optic nerve transection. CONCLUSION: Photocoagulation of the outer retina that completely destroys the photoreceptors results in survival of the overlying RGCs in experimental glaucoma in monkey eyes. CLINICAL RELEVANCE: Although this is an experimental model and not a therapeutic option, these results suggest that treatments other than lowering intraocular pressure may be potential therapies for preventing RGC death in glaucomatous eyes. Arch Ophthalmol. 2000;118:1242-1250