Comparison of clinical and biometric characteristics between nanophthalmic children and age-matched controls

Purpose:To compare the clinical and biometric characteristics of children presenting with nanophthalmos (NO group) with that of age-matched controls (CO group).Methods: Electronic medical records of 40 children (<18 years of age) with diagnosis of nanophthalmos (NO), presented to a tertiary center in Tamil Nadu between January 2010 and December 2019, were reviewed and compared with 30 age-matched controls (CO) presenting for routine eye examination between October 2019 and December 2019. Clinical parameters compared were best-corrected visual acuity (BCVA), axial length (AxL), keratometry (K), anterior chamber depth (ACD), lens thickness (LT), retinochoroidal scleral thickness (RCS), corneal diameter, central corneal thickness (CCT), intraocular pressure (IOP), lens axial length factor (LAF), and lens thickness/anterior chamber depth ratio (LT/ACD).Results: Mean age of the NO group was 8.95 ± 4.0 years. Mean spherical equivalent (SE) in NO group was 10.87 ± 3.1 D and was inversely correlated to AxL (r = −0.46, P value = 0.003). All biometric parameters (AxL, ACD, LT, RCS, LAF, and LT/ACD), except CCT were significantly different between NO and CO groups. NO group children had 52.5% visual impairment with BCVA ≤ 6/24 and 17.5% had esotropia. Common ocular associations in NO group were amblyopia (64.3%), primary angle-closure glaucoma (PACG) (17.8%), pigmentary retinopathy (14.3%), and retinal detachment (3.6%). Angle-closure disease was seen in 50% of NO group and 30% underwent laser peripheral iridotomy (LPI). There was a significant difference in SE, ACD, and LAF among NO children with AxL <17 mm or >17 mm. Multivariable regression analysis revealed a significant correlation of SE and ACD with AxL.Conclusion: Nanophthalmos in children often present as amblyopia with visual impairment and strabismus. NO group with AxL <17 mm, had angle-closure disease as a common association with significantly lower ACD, higher SE, and LAF. All morphometric characteristics, except CCT, were significantly different between NO and CO groups. Close monitoring with serial biometry in NO group is needed for the timely diagnosis and prompt intervention to avoid visual impairment, due to glaucoma.     

Medial patellofemoral ligament reconstruction in patellar instability

Background:

Medial patellofemoral ligament (MPFL) is one of the major static medial stabilising structures of the patella. MPFL is most often damaged in patients with patellar instability. Reconstruction of MPFL is becoming a common surgical procedure in treating patellar instability. We hypothesised that MPFL reconstruction was adequate to treat patients with patellar instability if the tibial tubercle and the centre of the trochlear groove (TT-TG) value was less than 20 mm and without a dysplastic trochlea.

Materials and Methods:

30 patients matching our inclusion criteria and operated between April 2009 and May 2011 were included in the study. MPFL reconstruction was performed using gracilis tendon fixed with endobutton on the patellar side and bio absorbable interference screw or staple on the femoral side. Patients were followed up with subjective criteria, Kujala score and Lysholm score.

Results:

The mean duration of followup was 25 months (range 14-38 months). The mean preoperative Kujala score was 47.5 and Lysholm score was 44.7. The mean postoperative Kujala score was 87 and Lysholm score was 88.06. None of the patients had redislocation.

Conclusion:

MPFL reconstruction using gracilis tendon gives excellent results in patients with patellar instability with no redislocations. Some patients may have persistence of apprehension.     

Inefficiency of metal chelators to promote recovery of methylmercury inhibited CNS succinic dehydrogenase.

This paper deals with the level of succinic dehydrogenase (SDH) in various locations of the central nervous system (CNS) of rat, treated with methylmercury chloride (MMC) and later with antagonists. None of the CNS areas reveals any effect after 2 days of MMC application, but further treatment causes a linear inhibition of the enzyme with increasing duration of MMC exposure. Maximal inhibition in all regions is exhibited after 15 days of treatment. In absolute terms, the maximal inhibition is observed in the olfactory bulbs and the minimal effect is seen in the spinal cord after 15 days with low and high doses of MMC respectively.     

Aetiology of childhood cataract in south India.

AIM: To identify the causes of childhood cataract in south India with emphasis on factors that might be potentially preventable. METHODS: A total of 514 consecutive children with cataract attending an eye hospital outpatient clinic were examined and their parents interviewed by a trained interviewer using a standardised questionnaire in the local language. Serology was performed on children under 1 year of age to detect congenital rubella syndrome (CRS). Other investigations were performed as clinically indicated. RESULTS: Of the 366 children with non-traumatic cataract 25% were hereditary, 15% were due to congenital rubella syndrome, and 51% were undetermined. In children under 1 year of age 25% were due to rubella and cataract of nuclear morphology had a 75% positive predictive value for CRS. Mothers of children in the undetermined group were more likely to have taken abortifacients than a group of age matched controls (p = 0.1) but use of other medications in pregnancy was similar in both groups. Of the 148 (29%) children with traumatic cataracts three quarters were over the age of 6 years. Stick injuries were responsible for 28%, thorn injuries for 21%, and firecrackers for 5%. CONCLUSION: Nearly half of non-traumatic cataract in south India is due to potentially preventable causes (CRS and autosomal dominant disease). There is need for further work to identify the factors leading to childhood cataract in at least half of the cases for which no definite cause can as yet be determined.     

Acute effect of 30 degrees, 60 degrees and 80 degrees head-down tilt on blood pressure in young healthy human subjects

There are very few reports on the acute cardiovascular responses to head-down tilt of more than 30 degrees on blood pressure (BP) and heart rate (HR) in human subjects. The aim of the present study was to determine the BP and HR response to five minutes of 30 degrees, 60 degrees and 80 degrees head-down tilt in healthy human subjects. The study was conducted on 20 healthy male volunteers aged 18-20 years. In this study, 30 degrees head-down tilt produced no significant change in BP and HR. With 60 degrees and 80 degrees head-down tilt, there was a significant graded increase in diastolic pressure and a decrease in pulse pressure (P<0.01 for both). This pressor response is most likely due to raised intracranial tension and/or hypoxemia in this condition. The decrease in pulse pressure is possibly due to excessive cardiopulmonary blood volume resulting in a decreased stroke volume. Our study confirms earlier findings that acute 30 degrees head-down tilt produces no significant changes in BP and HR. However, the mechanisms leading to increases in BP that occurred with 60 degrees and 80 degrees acute head-down tilt need to be investigated.