RESUMEN
Primitive neuroectodermal tumors of the central nervous system (CNS-PNETs) are highly aggressive, poorly differentiated embryonal tumors occurring predominantly in young children but also affecting adolescents and adults. Herein, we demonstrate that a significant proportion of institutionally diagnosed CNS-PNETs display molecular profiles indistinguishable from those of various other well-defined CNS tumor entities, facilitating diagnosis and appropriate therapy for patients with these tumors. From the remaining fraction of CNS-PNETs, we identify four new CNS tumor entities, each associated with a recurrent genetic alteration and distinct histopathological and clinical features. These new molecular entities, designated "CNS neuroblastoma with FOXR2 activation (CNS NB-FOXR2)," "CNS Ewing sarcoma family tumor with CIC alteration (CNS EFT-CIC)," "CNS high-grade neuroepithelial tumor with MN1 alteration (CNS HGNET-MN1)," and "CNS high-grade neuroepithelial tumor with BCOR alteration (CNS HGNET-BCOR)," will enable meaningful clinical trials and the development of therapeutic strategies for patients affected by poorly differentiated CNS tumors.
Asunto(s)
Neoplasias del Sistema Nervioso Central/genética , Neoplasias del Sistema Nervioso Central/patología , Metilación de ADN , Tumores Neuroectodérmicos/genética , Tumores Neuroectodérmicos/patología , Secuencia de Aminoácidos , Neoplasias del Sistema Nervioso Central/clasificación , Neoplasias del Sistema Nervioso Central/diagnóstico , Niño , Factores de Transcripción Forkhead/genética , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Datos de Secuencia Molecular , Tumores Neuroectodérmicos/clasificación , Tumores Neuroectodérmicos/diagnóstico , Proteínas Proto-Oncogénicas/química , Proteínas Proto-Oncogénicas/genética , Proteínas Represoras/química , Proteínas Represoras/genética , Transducción de Señal , Transactivadores , Proteínas Supresoras de Tumor/genéticaRESUMEN
BACKGROUND: Temporal artery biopsy (TAB) is performed during the diagnostic workup for giant cell arteritis (GCA), a vasculitis with the potential to cause irreversible blindness or stroke. However, treatment is often started on clinical grounds, and TAB result frequently does not influence patient management. The aim of this study was to assess the need for TAB in cases of suspected GCA. METHODS: We performed a retrospective review of 185 TABs performed in our institution from 1990 to 2010. Patients were identified through the Hospital In-Patient Enquiry database and theater records. Clinical findings, erythrocyte sedimentation rate, steroid treatment preoperatively, American College of Rheumatology (ACR) criteria for GCA score, biopsy result, and follow-up were recorded. RESULTS: Fifty-eight (31.4%) biopsies were positive for GCA. Presence of jaw claudication (P = 0.001), abnormal fundoscopy (P = 0.001), and raised erythrocyte sedimentation rate (P = 0.001) were significantly associated with GCA. The strongest association with positive biopsy was seen with the prebiopsy ACR score (P < 0.001). Twenty-four (13.7%) patients had undergone biopsy, despite no potential for meeting ACR criteria preoperatively. None of these were positive. Overall, 29 (16.4%) patients had management altered by TAB result. CONCLUSIONS: Our results confirm that TAB does not affect management in the majority of patients with suspected GCA. We conclude that TAB has benefit only for patients who score 2 or 3 on the ACR criteria for GCA without biopsy.
Asunto(s)
Arteritis de Células Gigantes/diagnóstico , Arterias Temporales/patología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Biopsia , Sedimentación Sanguínea , Distribución de Chi-Cuadrado , Reacciones Falso Negativas , Reacciones Falso Positivas , Femenino , Arteritis de Células Gigantes/complicaciones , Arteritis de Células Gigantes/tratamiento farmacológico , Arteritis de Células Gigantes/patología , Glucocorticoides/uso terapéutico , Humanos , Irlanda , Masculino , Persona de Mediana Edad , Análisis Multivariante , Oftalmoscopios , Oftalmoscopía , Valor Predictivo de las Pruebas , Pronóstico , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Índice de Severidad de la EnfermedadRESUMEN
We report a patient who presented with clinical and MRI findings suggestive of polymyositis but, in whom, muscle biopsy disclosed a strikingly different diagnosis. A 65-year-old woman presented with 3-week history of bilateral proximal muscle pain and weakness. Laboratory investigations showed markedly elevated inflammatory markers and mildly elevated muscle enzymes. MRI scans of lower limbs showed features suggestive of polymyositis. However, muscle biopsy showed features of a polyarteritis-type vasculitis affecting an intramuscular blood vessel. Our reports highlight the critical role of muscle biopsy in establishing the correct diagnosis in patients with suspected myositis.
Asunto(s)
Músculo Esquelético/patología , Poliarteritis Nudosa/patología , Polimiositis/patología , Anciano , Biopsia , Diagnóstico Diferencial , Femenino , HumanosRESUMEN
BACKGROUND AND OBJECTIVE: One-third of patients who undergo lumbar discectomy continue to suffer from persistent pain postoperatively. Greater preoperative warmth thresholds and greater preoperative cerebrospinal fluid concentrations of stable serum nitric oxide metabolites are associated with a worse outcome. The principal objective of this study was to examine the relationship between patient outcome (defined using the Modified Stauffer-Coventry evaluating criteria) and preoperative pain perception threshold to an electrical stimulus. METHODS: A prospective observational pilot study of patients (n = 39) was performed. Quantitative sensory testing, visual analogue scales for anxiety and pain, the Hospital Anxiety and Depression (HADS) Scale and the McGill Pain Questionnaire were completed, and serum nitric oxide metabolites were measured perioperatively. Excised disc tissue was examined histologically, and immunohistochemistry for phospholipase A2 was performed. RESULTS: Ten patients (26%) had an unsatisfactory outcome. Those with a satisfactory outcome had greater preoperative pain perception thresholds over the affected dermatome, which decreased by 2 months postoperatively. These patients also demonstrated a decrease in nitric oxide metabolites from preoperatively to 18 h postoperatively. Greater preoperative HADS scores, and greater pain intensity 4 h and 24 h postoperatively were associated with an unsatisfactory outcome. CONCLUSION: Patients with a satisfactory outcome demonstrate a decrease in pain perception thresholds and plasma concentration of stable nitric oxide metabolites during the perioperative period. Patients with an unsatisfactory outcome following lumbar discectomy experience greater preoperative anxiety and greater pain during the early postoperative period. These findings justify a larger prospective observational study.
Asunto(s)
Discectomía , Vértebras Lumbares/cirugía , Dimensión del Dolor/psicología , Umbral del Dolor/psicología , Dolor Postoperatorio/psicología , Cuidados Preoperatorios/psicología , Adulto , Discectomía/efectos adversos , Método Doble Ciego , Femenino , Humanos , Dolor de la Región Lumbar/psicología , Dolor de la Región Lumbar/cirugía , Vértebras Lumbares/patología , Masculino , Persona de Mediana Edad , Dimensión del Dolor/métodos , Dolor Postoperatorio/prevención & control , Proyectos Piloto , Cuidados Preoperatorios/métodos , Estudios Prospectivos , Resultado del Tratamiento , Adulto JovenRESUMEN
The mechanisms of neuronal apoptosis in Creutzfeldt-Jakob disease (CJD) and their relationship to accumulated prion protein (PrP) are unclear. A recent cell culture study showed that intracytoplasmic PrP may induce phosphorylated RNA-dependent protein kinase (PKR(p))-mediated cell stress. The double-stranded RNA protein kinase PKR is a proapoptotic and stress kinase that accumulates in degenerating neurons in Alzheimer disease. To determine whether neuronal apoptosis in human CJD is associated with activation of the PKR(p) signaling pathway, we assessed in situ end labeling and immunocytochemistry for PrP, glial fibrillary acidic protein, CD68, activated caspase 3, and phosphorylated PKR (Thr451) in samples of frontal, occipital, and temporal cortex, striatum, and cerebellum from 6 patients with sporadic CJD and 5 controls. Neuronal immunostaining for activated PKR was found in all CJD cases. The most staining was in nuclei and, in contrast to findings in Alzheimer disease, cytoplasmic labeling was not detected. Both the number and distribution of PKR(p)-positive neurons correlated closely with the extent of neuronal apoptosis, spongiosis, astrocytosis, and microglial activation and with the phenotype and disease severity. There was no correlation with the type, topography, or amount of extracellular PrP deposits. These findings suggest that neuronal apoptosis in human CJD may result from PKR(p)-mediated cell stress and are consistent with recent studies supporting a pathogenic role for intracellular or transmembrane PrP.
Asunto(s)
Encéfalo/enzimología , Síndrome de Creutzfeldt-Jakob/enzimología , Síndrome de Creutzfeldt-Jakob/genética , Neuronas/enzimología , Priones/metabolismo , eIF-2 Quinasa/metabolismo , Anciano , Anciano de 80 o más Años , Apoptosis/fisiología , Encéfalo/patología , Caspasa 3/análisis , Caspasa 3/metabolismo , Núcleo Celular/enzimología , Núcleo Celular/patología , Síndrome de Creutzfeldt-Jakob/patología , Femenino , Proteína Ácida Fibrilar de la Glía/análisis , Proteína Ácida Fibrilar de la Glía/metabolismo , Gliosis/enzimología , Gliosis/etiología , Gliosis/patología , Humanos , Inmunohistoquímica , Etiquetado Corte-Fin in Situ , Masculino , Persona de Mediana Edad , Degeneración Nerviosa/enzimología , Degeneración Nerviosa/etiología , Degeneración Nerviosa/patología , Neuronas/patología , Fosforilación , Priones/análisis , Estrés Fisiológico/fisiologíaRESUMEN
BACKGROUND: Frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17) is associated with mutations in the Microtubule-Associated Protein Tau(MAPT) gene or the Progranulin(PGRN) gene. MAPT mutations lead to widespread deposition of hyperphosphorylated tau protein (FTDP-17T). PGRN mutations are associated with ubiquitin- and TDP-43-positive inclusions in the frontotemporal cortex, striatum and hippocampus (FTDP-17U). Despite the differences, FTDP-17T and FTDP-17U share a largely overlapping clinical phenotype. OBJECTIVE: To determine whether neuroimaging studies may allow an in vivo early differentiation between FTDP-17T and FTDP-17U. METHODS: We studied 25 individuals affected with FTDP-17T associated with either the exon 10+3 (24 subjects) or the G335S (1 subject) MAPT mutation, as well as 3 FTDP-17U individuals, who were carriers of the A9D, IVS6-2A>G or R493X PGRN mutation. Neuroimaging studies, obtained along the course of the disease, were compared to the neuropathologic findings. RESULTS: FTDP-17T cases were associated with symmetric frontotemporal atrophy. Behavioral changes constituted the predominant clinical presentation. Conversely, an asymmetric degenerative process was seen in all 3 PGRN cases, who presented with either corticobasal syndrome (A9D) or frontotemporal dementia and language deterioration (IVS6-2A>G and R493X). CONCLUSION: Neuroimaging data, in the early disease stage of FTDP-17, may offer the possibility of an early differentiation of FTDP-17T and FTDP-17U phenotypes, independent of the genetic analysis.
Asunto(s)
Cromosomas Humanos Par 17/genética , Demencia/genética , Ligamiento Genético/genética , Trastornos Parkinsonianos/genética , Autopsia , Demencia/diagnóstico , Demencia/patología , Humanos , Lenguaje , Mutación/genética , Trastornos Parkinsonianos/diagnóstico , Trastornos Parkinsonianos/patología , Fenotipo , Estudios Retrospectivos , SíndromeRESUMEN
Macrophagic myofasciitis (MMF) is an uncommon inflammatory disorder of muscle believed to be due to persistence of vaccine-derived aluminium hydroxide at the site of injection. The condition is characterised by diffuse myalgias, arthralgia and fatigue. We describe a patient with histologically confirmed MMF whose presentation was atypical with left chest and upper limb pain beginning more than 10 years post vaccination. Treatment with steroids led to symptomatic improvement. Although rare, clinicians should consider MMF in cases of atypical myalgia.
Asunto(s)
Enfermedades del Sistema Inmune/inducido químicamente , Activación de Macrófagos/efectos de los fármacos , Músculo Esquelético/efectos de los fármacos , Miositis/inducido químicamente , Vacunación/efectos adversos , Hidróxido de Aluminio/efectos adversos , Antiinflamatorios/uso terapéutico , Femenino , Antígenos de Histocompatibilidad Clase II/análisis , Antígenos de Histocompatibilidad Clase II/metabolismo , Humanos , Sistema Inmunológico/efectos de los fármacos , Sistema Inmunológico/fisiopatología , Enfermedades del Sistema Inmune/metabolismo , Enfermedades del Sistema Inmune/fisiopatología , Activación de Macrófagos/fisiología , Persona de Mediana Edad , Músculo Esquelético/patología , Músculo Esquelético/fisiopatología , Miositis/metabolismo , Miositis/fisiopatología , Esteroides/uso terapéutico , Tiempo , Factores de TiempoRESUMEN
BACKGROUND: Spindle cell pseudotumors are formed by histiocytes in response to infection by Mycobacterium avium-intracellulare complex (MAC) and are rare in patients without AIDS. CASE DESCRIPTION: A 66-year-old man presented with neck pain, ataxia, and a history of sarcoidosis. A cerebellar lesion was identified on magnetic resonance imaging and surgically excised. Histopathology revealed this to be a spindle cell pseudotumor and MAC was isolated by bacterial culture of cerebrospinal fluid. Hematology revealed cluster of differentiation 4 lymphocytopenia but human immunodeficiency virus serology was negative. The patient was commenced on antimicrobial treatment that included a macrolide and remained well at 1 year follow-up. CONCLUSIONS: This rare presentation of isolated intracranial MAC was treated with surgical excision and antimicrobials with a good outcome.
Asunto(s)
Enfermedades Cerebelosas/patología , Enfermedades Cerebelosas/terapia , Infección por Mycobacterium avium-intracellulare/patología , Infección por Mycobacterium avium-intracellulare/terapia , Síndrome de Inmunodeficiencia Adquirida , Anciano , Antibacterianos/administración & dosificación , Terapia Combinada/métodos , Diagnóstico Diferencial , Humanos , Masculino , Procedimientos Neuroquirúrgicos/métodos , Resultado del TratamientoRESUMEN
Chordoma is a locally invasive tumor of low metastatic potential. Only six cases of chordoma that metastasized to the brain are found in the English literature. Most of these lesions were clinically silent and all were associated with extraneural metastases. The authors report a case of symptomatic brain metastasis from a sacrococcygeal chordoma in the absence of other metastases. The incidence, sites, and factors predictive of chordoma metastasis are discussed.
Asunto(s)
Neoplasias Encefálicas/secundario , Cordoma/secundario , Región Sacrococcígea/patología , Neoplasias de la Médula Espinal/patología , Anciano , Humanos , MasculinoRESUMEN
Despite the fact that gout is a common metabolic disorder, because its involvement of the axial skeleton is rare the diagnosis is often delayed, even in patients with long-standing gout who present with neurological deficits. The authors report the case of a woman with a history of extensive gout, emphasizing the clinical, radiological, and pathological features of a lumbar spinal stenosis.
Asunto(s)
Gota/complicaciones , Vértebras Lumbares , Compresión de la Médula Espinal/etiología , Enfermedades de la Columna Vertebral/complicaciones , Estenosis Espinal/etiología , Vértebras Torácicas , Biopsia , Diagnóstico Diferencial , Femenino , Gota/diagnóstico , Gota/patología , Humanos , Procesamiento de Imagen Asistido por Computador , Laminectomía , Vértebras Lumbares/patología , Vértebras Lumbares/cirugía , Imagen por Resonancia Magnética , Persona de Mediana Edad , Neuronavegación , Compresión de la Médula Espinal/diagnóstico , Compresión de la Médula Espinal/patología , Compresión de la Médula Espinal/cirugía , Enfermedades de la Columna Vertebral/diagnóstico , Enfermedades de la Columna Vertebral/patología , Enfermedades de la Columna Vertebral/cirugía , Estenosis Espinal/diagnóstico , Estenosis Espinal/patología , Estenosis Espinal/cirugía , Vértebras Torácicas/patología , Vértebras Torácicas/cirugía , Tomografía Computarizada por Rayos XRESUMEN
Epithelioid hemangioendothelioma (EH) is a rare tumor of vascular origin. The authors describe two cases of spinal EH, one involving the T-10 vertebra and the second involving the upper cervical spine. In the first case the patient underwent resection of the tumor; this case represents the longest reported follow-up period for spinal EH. In the second case, extensive involvement of C-2, C-3, and C-4 as well as encasement of both vertebral arteries precluded safe tumor resection, and posterior occipitocervical stabilization was performed. The patient subsequently died of metastatic disease. The findings in these two cases underscore the difficulty in predicting the clinical behavior of spinal EH based solely on histological and clinical features as well as the uncertainty of the roles of surgery, chemotherapy, and radiotherapy in the oncological management of a spinal tumor for which clinical data are very limited.
Asunto(s)
Hemangioendotelioma Epitelioide/cirugía , Neoplasias de la Columna Vertebral/cirugía , Adolescente , Tornillos Óseos , Vértebras Cervicales/patología , Resultado Fatal , Hemangioendotelioma Epitelioide/patología , Humanos , Dolor de la Región Lumbar/etiología , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Neoplasias de la Columna Vertebral/patología , Vértebras Torácicas/patología , Arteria Vertebral/patologíaRESUMEN
This 40-year-old man presented with a 5-month history of progressive right-sided headache associated with visual blurring. He also had a history of epilepsy but had been seizure free with medication for the past 10 years. An initial CT scan of his brain performed 16 years previously had revealed a small area of calcification in the right parietal region. In the current presentation, he had a left-sided homonymous hemianopia but no other neurological deficits. A CT scan of his brain showed a much larger calcified, partly cystic lesion in the right parietal region. Because he was symptomatic, the lesion was excised and the cyst was drained. Histological examination of the excised tissue showed an unusual primary tumor that was difficult to classify but had some features of angiocentric glioma. The heavy calcification, mixed-density cell population, and regions with features of angiocentric glioma were most unusual. The patient remained asymptomatic 5 years after surgery, and follow-up scans did not show recurrence.
Asunto(s)
Neoplasias Encefálicas/patología , Calcinosis/patología , Glioma/patología , Adulto , Drenaje , Epilepsia/complicaciones , Hemianopsia/patología , Humanos , Masculino , Procedimientos Neuroquirúrgicos , Lóbulo Parietal/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Resultado del TratamientoRESUMEN
We describe a case of giant spinal ependymoma of cervicothoracic spine in a 30-year-old lady who presented with progressive spastic paraparesis and significant combined upper and lower motor neuron signs in her lower limbs over a 1-year period. She also had upper limb small muscle wasting with absent reflexes and diminished sensation. She was wheel chair bound with involvement of sphincters. Neuroimaging revealed a uniformly enhancing intramedullary lesion from C2-T3 level with associated syringomyelia. She underwent a complete excision of this World Health Organisation (WHO) II cellular ependymoma, resulting in significant clinical outcome and improvement in bladder and bowel function.
Asunto(s)
Ependimoma/diagnóstico , Neoplasias de la Médula Espinal/diagnóstico , Adulto , Vértebras Cervicales , Diagnóstico Diferencial , Femenino , Humanos , Imagen por Resonancia Magnética , Vértebras TorácicasRESUMEN
The authors describe an unusual case of metastatic thyroid follicular adenocarcinoma presenting with sciatica in a 79-year-old woman. The primary thyroid tumour was undiagnosed until this clinical presentation. The patient gave a short history of back pain and right-sided sciatica, which was progressive and nocturnal in nature. Neuroimaging revealed an enhancing intradural mass lesion, which was completely excised through a right L1-L3 hemilaminectomy. Histopathological examination of the excised tissue revealed a follicular thyroid carcinoma. Subsequent metastatic investigation revealed a heterogeneously attenuating mixed solid cystic mass in a retrosternal thyroid gland, with multiple solid pulmonary nodules suggestive of metastatic disease. She opted for palliative radiotherapy for the primary thyroid cancer and made remarkable postoperative improvement. The authors conclude that surgical treatment of solitary metastatic lesion may produce good symptomatic relief irrespective of patient's age and primary pathology, while emphasising the need for detailed clinical evaluation of patients with 'red flag' symptoms.
Asunto(s)
Adenocarcinoma Folicular/secundario , Cuidados Paliativos , Ciática/etiología , Neoplasias de la Médula Espinal/secundario , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/radioterapia , Adenocarcinoma Folicular/complicaciones , Adenocarcinoma Folicular/cirugía , Anciano , Femenino , Humanos , Vértebras Lumbares , Neuroimagen , Neoplasias de la Médula Espinal/cirugía , Neoplasias de la Tiroides/complicacionesAsunto(s)
Terapia Antirretroviral Altamente Activa , Trastornos del Conocimiento/etiología , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Encéfalo/efectos de los fármacos , Trastornos del Conocimiento/virología , Infecciones por VIH/virología , Humanos , PronósticoRESUMEN
The finding of heterotopic gastric mucosa in the rectum is rare, with less than 40 reported cases in the literature. A condition of unknown etiology, several hypotheses exist including infectious and congenital. We report a case of ectopic gastric tissue in the rectum of a 47-year-old female, and her subsequent clinical course. Furthermore for the first time, we present immunohistologic evidence of the presence of Helicobacter pylori in rectal ectopic gastric tissue.
Asunto(s)
Coristoma/complicaciones , Coristoma/microbiología , Mucosa Gástrica/microbiología , Infecciones por Helicobacter/complicaciones , Helicobacter pylori , Enfermedades del Recto/complicaciones , Coristoma/diagnóstico , Femenino , Humanos , Persona de Mediana Edad , Enfermedades del Recto/diagnósticoAsunto(s)
Malformaciones del Desarrollo Cortical/diagnóstico , Mucosa Bucal/patología , Tumores Odontogénicos/diagnóstico , Esclerodermia Localizada/diagnóstico , Convulsiones/diagnóstico , Adulto , Humanos , Masculino , Malformaciones del Desarrollo Cortical/complicaciones , Tumores Odontogénicos/complicaciones , Esclerodermia Localizada/complicaciones , Convulsiones/complicacionesRESUMEN
Mutations in Tau cause the inherited neurodegenerative disease, frontotemporal dementia and Parkinsonism linked to chromosome 17 (FTDP-17). Known coding region mutations cluster in the microtubule-binding region, where they alter the ability of tau to promote microtubule assembly. Depending on the tau isoforms, this region consists of three or four imperfect repeats of 31 or 32 amino acids, each of which contains a characteristic and invariant PGGG motif. Here, we report the novel G335S mutation, which changes the PGGG motif of the third tau repeat to PGGS, in an individual who developed social withdrawal, emotional bluntness and stereotypic behavior at age 22, followed by disinhibition, hyperorality and ideomotor apraxia. Abundant tau-positive inclusions were present in neurons and glia in the frontotemporal cortex, hippocampus and brainstem. Sarkosyl-insoluble tau showed paired helical and straight filaments, as well as more irregular rope-like filaments. The pattern of pathological tau bands was like that of Alzheimer disease. Experimentally, the G335S mutation resulted in a greatly reduced ability of tau to promote microtubule assembly, while having no significant effect on heparin-induced assembly of recombinant tau into filaments.
Asunto(s)
Demencia/genética , Glicina/genética , Mutación , Serina/genética , Proteínas tau/genética , Adulto , Análisis Mutacional de ADN/métodos , Demencia/metabolismo , Demencia/patología , Humanos , Masculino , Microscopía Electrónica de Transmisión , Microtúbulos/patología , Microtúbulos/ultraestructura , Ovillos Neurofibrilares/metabolismo , Ovillos Neurofibrilares/patología , Ovillos Neurofibrilares/ultraestructura , Proteínas tau/ultraestructuraRESUMEN
BACKGROUND: The beneficial effects of adjuvant treatment with agents such as autologous platelet concentrate (APC) or autologous serum (AS) in the surgical management of macular holes remain uncertain. The purpose of this study was to determine the histological changes induced by these agents compared with control on retinal wound healing in an animal model. METHODS: The right eyes of 51 pigmented rabbits were used. Under anaesthesia, full-thickness sensory retinal incisions 2 mm in length were made into avascular retina down to the level of the retinal pigment epithelium using a 23-gauge needle via a superotemporal sclerotomy. APC, AS or sterilised balanced salt solution was placed directly over the wound site. Animals were killed at 3, 7 or 14 days and the wounds examined immunohistologically. Proliferating cell nuclear antigen (PCNA) was used to detect proliferating cells. RESULTS: No difference was observed between serum-treated eyes and control eyes. A greater displacement or migration of cells toward the retinal surface was consistently found in the APC-treated wounds than in control wounds. These cells were of mixed origin but appeared to arise predominantly from the outer nuclear layer. A significantly greater number of PCNA-staining cells was found in the platelet-treated group than in controls at 3 days (P=0.038), 7 days (P=0.039) and 14 days (P=0.038). CONCLUSION: We have demonstrated a significantly greater proliferative cellular response in the healing of retinal wounds with the use of platelet concentrate than in control wounds. We consider that this model may be used in further studies on the effects of other agents on retinal wound healing.