The optic nerve develops from the embryonic optic stalk, which appears at the fourth week and connects the optic vesicle to the forebrain. As the stalk lengthens, it becomes thinner and the lumen is progressively occupied by the axons growing from the ganglion cells of the retina (the seventh week, 15-mm stage). In the meantime, the embryonic cleft closes at the sixth week of gestation. At the eighth week, axons fully occupy the stalk and reach the brain and a rudimentary optic chiasma is established. The mechanism by which the embryonic retinal ganglion cell axons reach the optic disc remains unclear. Many factors, such as the paired box containing the Pax2 gene the axon guidance molecule netrin-1 and other cell surface or extracellular matrix component may be involved in axon path finding mechanisms. Expression errors of these molecules lead to optic nerve hypoplasia 2 . The axons of the optic nerve are surrounded by myelin sheaths. Myelinization begins centrally, progresses in a centrifugal direction toward the eye, and terminates at the level of the lamina cribrosa. The myelin sheath is produced by oligodendrocytes, and myelinization is usually complete shortly after birth.
This is to certify that this dissertation entitled "CORRELATION OF RETINAL NERVE FIBRE LAYER THICKNESS IN OPTICAL COHERENCE TOMOGRAPHY WITH VISUALOUTCOME IN OPTICNEURITIS" is a bonafide record of the research work done by Dr. C.USHA, post graduate in Regional Institute of Ophthalmology and Government Ophthalmic Hospital, Madras Medical College and Government General Hospital, Chennai-03, in partial fulfillment of the regulations laid down by The Tamil Nadu Dr. M.G.R. Medical University for the award of M.S. Ophthalmology Branch III, under my guidance and supervision during the academic years 2013 - 2015.
Michael J. Wan et al (57) made a retrospective study of 59 pediatric patients with first episode opticneuritis. The mean age was 12.6 years, 72% were female, 41% had bilateral involvement, 52% had or developed an underlying diagnosis (39% multiple sclerosis, 7% ADEM, 7% neuro myelitis optica) & 91% received treatment (85% steroids, 7% multimodal). A poor visualoutcome at 1 year (<20/40) was associated with vision of (<20/20) at 3 months(P= 0.041). other clinical characteristics including visual acuity at presentation, sex, bilateral involvement, optic nerve edema & underlying diagnoses were not significantly associated with poor visual outcomes.
Regardless of whether ON is treated or not, the visual function starts to recover within 1 month [3, 22]. As ON improves spontaneously, treatment with corticosteroids has been questioned. A Cochrane review found that there was no evidence of any beneficial effect of oral or i.v. corticosteroids compared to placebo regarding visual acuity, visual field or contrast sensitivity outcomes . However, even when visual acuity returns to normal, many patients have lasting symptoms of visual disability . Optimal treatment should include the rapid relief of symptoms, as well as the prevention of tissue damage. Previous studies have shown that treatment with corti- costeroids in ON has an effect on the rate of recovery and that the short-term risk of development of MS is re- duced . The effects of corticosteroid treatment have also been evaluated on brain MRI-derived quantities in MS, including gadolinium-enhancing lesions, showing a decrease in the number of lesions after treatment, also indicating the positive effect of corticosteroids [26, 27].
From the pretectal nucleus crossed and uncrossed fibres project to ipsilateral and contralateral Edinger-Westpal nucleus in the midbrain. From here parasympathetic fibres project along with oculomotor (III cranial nerve) to synapse with postganglionic parasympathetic neurons of ciliary ganglion innervating ciliary sphincter. Due to decussation twice, one in optic chiasm and the other between pretectal nuclei and Edinger-Westpal nucleus, direct pupillary response in one eye equals consensual response in the other eye.
Corticosteroids (CS) have been recommended for treating acute ON relapses. There is still no consensus about the application of CS (intravenous [iv] or oral forms), dosage, and treatment duration. Often, clinical presentation of opticneuritis is the main factor for the decision maker for initiat- ing and duration of acute therapy. ONTT is a multicentered randomized clinical trial that assessed multiple parameters for patients with ON. ONTT also questioned acute management strategies and in a previous study, patients were assigned to three groups: 1) patients on oral prednisone (1 mg/kg/d for 14 days), 2) patients who received iv methylprednisolone (MP, 250 mg every 6 hours for 3 days) followed by an oral prednisone taper (1 mg/kg/d for 11 days), or 3) patients on oral placebo (for 14 days). Each regimen was followed by a short oral dosage taper of prednisone or placebo on days 15, 16, and 18. ONTT showed that while high-dose CS accelerated visual recovery, long-term visualoutcome did not change when compared to the placebo. Visual outcomes for the patient group on oral CS did not improve and ONTT results even showed an increased recurrence rate in the same or fellow eye (twofold). Thus, the recommendation of ONTT is to treat acute ON with iv high-dose CS. Oral CS treat- ments did not seem to have a beneficial effect and thus they are not recommended. 30,31 When patients were followed up
1997 to 2011. Our search was made on keywords of “optic neuropathy,” “child,” and “biotinidase deficiency”. We documented seven patients, and reviewed their age, gender, ocular features, funduscopy, systemic features and onset of biotinidase deficiency, treatment received, and their final visualoutcome. They presented with ocular signs at ages ranging between 5 and 15 years old. Six of seven patients (85.7%) presented with optic atrophy in both eyes, while the remaining one patient (14.3%) displayed normal looking optic discs bilaterally. 2–5,9–10 Unfortunately, the final visual
Abstract: Acute opticneuritis (ON) has various etiologies. The most common presentation is inflammatory, demyelinating, idiopathic, or “typical” ON, which may be associated with multiple sclerosis. This must be differentiated from “atypical” causes of ON, which differ in their clinical presentation, natural history, management, and prognosis. Clinical “red flags” for an atypical cause of ON include absent or persistent pain, exudates and hemorrhages on fundoscopy, very severe, bilateral, or progressive visual loss, and failure to recover. In typical ON, steroids shorten the duration of the attack, but do not influence visualoutcome. This is in contrast to atypical ON associated with conditions such as sarcoidosis and neuromyelitis optica, which require aggres- sive immunosuppression and sometimes plasma exchange. The visual prognosis of typical ON is generally good. The prognosis in atypical ON is more variable. New developments aimed at designing better treatments for patients who fail to recover are discussed, focusing on recent research elucidating mechanisms of damage and recovery in ON. Future therapeutic directions may include enhancing repair processes, such as remyelination or adaptive neuroplasticity, or alternative methods of immunomodulation. Pilot studies investigating the safety and proof-of- principle of stem cell treatment are currently underway.
Opticneuritis (ON) is a recognized condition, yet factorsinfluencing recovery of vision are currently unknown. The purpose of this study was to identify prognostic factors for recovery of vision in canine ON of unknown etiology. Clinical databases of three referral hospitals were searched for dogs with presumptive ON based on clinicopathologic, MRI/CT, and fundoscopic findings. Twenty-six dogs diagnosed with presumptive ON of unknown etiology, isolated (I-ON) and MUE-associated (MUE-ON), were included in the study. Their medical records were reviewed retrospectively, and the association of complete recovery of vision with signalment, clinicopathologic findings, and treatment was investigated. Datasets were tested for normality using the D’Agostino and Shapiro-Wilk tests. Individual datasets were compared using the Chi-squared test, Fisher’s exact test, and the Mann-Whitney U-test. For multiple comparisons with parametric datasets, the one-way analysis of variance (ANOVA) was performed, and for non-parametric datasets, the Kruskal-Wallis test was performed to test for independence. For all data, averages are expressed as median with interquartile range and significance set at p < 0.05. Twenty-six dogs met the inclusion criteria. Median follow-up was 230 days (range 21–1901 days, mean 496 days). Six dogs (23%) achieved complete recovery and 20 dogs (77%) incomplete or no recovery of vision. The presence of a reactive pupillary light reflex (p = 0.013), the absence of fundoscopic lesions (p = 0.0006), a younger age (p = 0.038), and a lower cerebrospinal fluid (CSF) total nucleated cell count (TNCC) (p = 0.022) were statistically associated with complete recovery of vision. Dogs with I-ON were significantly younger (p = 0.046) and had lower CSF TNCC (p = 0.030) compared to the MUE-ON group. This study identified prognostic factors that may influence complete recovery of vision in dogs with ON. A larger cohort of dogs is required to determine whether these findings are robust and whether additional parameters aid accurate prognosis for recovery of vision in canine ON.
and were not considered typical of MS, and hypothalamic involvement has been emphasized . NMO has a more negative outcome than MS, with frequent and early relapses. Within 5 years of onset, 50% of patients have become blind in both eyes and cannot walk unassisted, and 20% die of respiratory failure due to cervical myelitis . Although no controlled therapeutic trials have been specifically performed in NMO, case series and observa- tional studies suggest that azathioprine in combination with oral steroid reduces the frequency of attacks [4,5], and rituximab and plasmapheresis can induce clinical remission of NMO [6-8]. Immuno-suppression rather than interferon β is the preferred treatment. Thus, distin- guishing NMO from MS is very important for the thera- peutic strategy of these disorders. Recently, clinical,
Choroiditis patch are seen in toxocara / toxoplasma infections. Active patches are yellowish, fluffy, raised from the surface of Retina Old patches are flushed, pigmented, irregular in nature. Choroidal effusion leading to exudative retinal detachment are seen. Old and recurrent inflammations lead to total detachment. Periphlebitis are associated with intermediate uveitis (pars - planitis) Optic nerve involvement seen due to inflammation of vitreous or choroid or due to post inflammatory glaucoma.
Using ROC analysis ,a cut-off value for mortality was calculated for each risk factor.X2 test was used to test these factors and logistic multiple regression and the factor found significant on this analysis were used to construct a new simplified Jabalpur prognostic scoring system Each factor was given a score depending on its severity, which is based onAPACHEII scoring system. This Jabalpur scoring system was prospectively validated in next 50 consecutive patients and compared to existing system.
MHV-A59 and MHV-2 were propagated and assayed as described previously (20). Four-week-old, virus-free, C57BL/6 mice (Jackson Laboratory) were inoculated intracranially with 50% lethal doses of MHV-A59 (2,000 PFU) or MHV-2 (50 PFU), as described previously (20), and monitored daily for mortality and signs of disease (15, 20). Mice were sacrificed 3, 5, 7, 15, or 30 days postinoculation and perfused with phos- phate-buffered saline followed by phosphate-buffered saline containing 4% paraformaldehyde. Liver, brain, spinal cord, and optic nerve tissues were collected, postfixed in 4% para- formaldehyde overnight at room temperature, and embedded in paraffin. To confirm expected virulence, livers were cut in 5- m sections and stained with hematoxylin and eosin (H&E), and pathology of moderate to severe hepatitis was character- ized by multiple foci of necrosis (data not shown), similarly to * Corresponding author. Mailing address: 302 JHN, 900 Walnut
Factors Influencing the Outcome of Arthrodesis for Congenital Kyphosis and Kyphoscoliosis ORIGINAL ARTICLE Factors Influencing the Outcome of Arthrodesis for Congenital Kyphosis and Kyphoscoliosis S H[.]
based on prior game median data. The logistic regression model correctly predicted 68/100 = 68% of games, while the point spread model correctly predicted 64/100 = 64% of games. A random sample of 75 games was also taken from the 2012-2013 Season. The same procedures were used to try to predict the outcome of a basketball game using both the logistic and point spread models estimat- ing the variable differences in the model by considering the past four games played by both teams and taking the differences of the medians of the four factors used in both models. Overall, approximately the same results were obtained as when a sample of the 2011-2012 games was taken. The point spread model correctly predicted 62.67% of the games correctly, while the logistic model predicted 66.67% of the games correctly.
It is now proved beyond doubt that acute myocardial infarction occurs as a result of disruption of a coronary artery plaque at a site of high density of inflammatory cells namely macrophages and T lymphocytes. Thus acute myocardial infarction can be thought of as resulting from acute exacerbation of a chronic inflammatory response. Precipitating factors work by exacerbating the inflammatory response and of increasing the physical focus impinging on coronary artery lesion weakened by inflammation, leading to rupture.
The major finding of this study is that the location of the infarct significantly affects the outcome of thrombolysis. Those with inferior wall myocardial infarction have a 3.18 times chance of undergoing successful thrombolysis compared to anterior wall myocardial infarction (P=0.02). This is after adjustment for all confounding variable like time window, age, smoking status, gender, diabetes and hypertension.
When compared to other studies (Table 43) this study shows an increase in the number of poor results. One of the causative factors may be a significant delay between seeing the patient and carrying out operative treatment. None of these patients were taken up for surgery within the golden six hour period after injury. The mean time before operation was 42.6 hours. The results of this series of operated patients compares badly even when compared to the studies reported in era prior to operative treatment.
Our study is the first to report transorbital sonographic measure- ment of both the ONSD and OND in patients with acute ON. Patients with ON had significantly increased ONSD values in the affected eye compared with the other eye and with values in age- matched controls. The thickening of the perineural space sur- rounding the optic nerve is probably related to inflammation of the optic nerve, resulting in an increase of the perineural sub- arachnoid fluid or edema caused by an impairment of axoplasmic flow, depending on the acute demyelinating plaque. Most inter- esting, it has been reported that narrowed optic canals, occurring for instance in osteopetrosis, may lead to compressive optic neu- ropathy. 18,19 It is, therefore, possible that within the anatomic
Abstract: This study was to investigate the fractional anisotropy (FA) and mean diffusion (MD) values of diffusion tensor imaging (DTI) in the whole-brain voxel-based analysis of opticneuritis (ON) patients and examine their rela- tionship with visual evoked potentials. A total of 12 (4 male, 8 female) patients with ON and 12 age-, sex-, and edu- cation-matched healthy controls (HCs) underwent magnetic resonance imaging (MRI). Imaging data were analyzed using two-sample t-tests to identify group differences in FA and MD values. Correlation analyses were performed to explore relationships between the FA and MD values of different brain regions and visual evoked potential (VEP) in subjects with ON. Compared with HCs, ON patients exhibited significantly decreased FA in the left cerebellum posterior lobe, left superior temporal gyrus, left extra-nuclear1, right middle frontal gyrus, and left middle frontal gyrus and increased FA in the right cerebellum_crus, right lentiform nucleus, bilateral anterior cingulum, left extra- nuclear2 and left precuneus. Meanwhile, increased MD was observed in the left inferior temporal gyrus, left supe- rior temporal gyrus, left hippocampus, left anterior cingulate/caudate, right superior frontal gyrus, right precentral gyrus, and left inferior parietal lobule. VEP latency of the right eye in ON correlated positively with the FA values of the bilateral anterior cingulum (r = -0.583, P = 0.047) and negatively with the FA values of the left superior temporal gyrus (r = 0.653, P = 0.021). VEP amplitude of the right eye in ON subjects negatively correlated with the FA values of the left extra-nuclear2 (r = -0.592, P = 0.043). VEP latency of the left eye in ON correlated positively with the MD value of the left anterior cingulate/caudate (r = 0.707, P = 0.010) and negatively with MD values of the left inferior parietal lobule (r = 0.670, P = 0.017), while VEP amplitude of the left eye in ON showed negative correlation with MD values of the left inferior parietal lobule (r = -0.684, P = 0.014). These results suggest significant brain involvement in ON, which may reflect the underlying pathologic mechanism. Correlational results demonstrate that VEP in ON is closely associated with FA and MD in multiple brain regions.