PubMed Health⌕ Search

Biomedical subjects

K K Nischal

Publications and source records attributed to K K Nischal.

At least 19 recordsLinked to original sources

A child with laryngo-onychocutaneous syndrome partially responsive to treatment with thalidomide.

Laryngo-onychocutaneous syndrome (LOCS) is a condition characterized by erosive or ulcerative skin lesions associated with excessive granulation tissue, at sites of trauma such as the digits, elbows and knees. Similar lesions can occur within the conjunctival mucosa, leading to corneal scarring and blindness. The main complications, however, occur in the respiratory tract, where a similar process of erosions and subsequent formation of granulation tissue causes airway obstruction which may lead to premature death. LOCS is now believed to be a nonblistering variant of junctional epidermolysis bullosa and to date there are no efficacious treatments available. We report a 16-year-old girl with LOCS who failed to respond to methylprednisolone and cyclophosphamide, but had a partial response to oral thalidomide with marked decrease in granulation tissue and tracheal secretions. Interruption of treatment resulted in prompt resurgence of the granulation tissue which was again controlled by reintroduction of thalidomide. We propose that in the absence of effective therapies for LOCS, a trial of thalidomide in these patients should be considered.

Adolescent↗

Penetrating orbital trauma by stiletto causing complex cranial neuropathies.

Penetrating orbital injuries pose a serious threat to vision, ocular motility, and in some cases, life. Long, sharp stiletto objects may penetrate deeply, causing catastrophic damage to orbital structures, despite seemingly trivial entry wounds. The authors present two cases of penetrating orbital injuries by stiletto objects, both entering via small eyelid wounds. Traumatic optic neuropathy occurred in both cases, and was treated with corticosteroids, however the globes escaped direct injury. Injuries to the IIIrd and VIth cranial nerves were also observed. Deep orbital injuries must be excluded in patients presenting with small eyelid wounds caused by sharp penetrating objects.

Adolescent↗

Management of intracorneal bleb after trabeculectomy for congenital glaucoma.

PURPOSE: Congenital glaucoma is a well-recognized entity that can occur in the presence of anterior segment dysgenesis. Trabeculectomy is an accepted intervention in the management of congenital glaucoma. The surgical technique as well as complications is well described. METHODS: This is a case report of a 3-month-old girl with anterior segment dysgenesis and glaucoma. She was referred post-trabeculectomy with persistent corneal opacity to be considered for penetrating keratoplasty and was found to have intrastromal corneal bleb. RESULTS: Ultrasound biomicroscopy confirmed communication of the corneal bleb with the anterior chamber, and the bleb was treated by autologous blood injection at the trabeculectomy site, under acetazolamide cover. CONCLUSIONS: We present evidence suggesting that abnormal structure was the etiologic basis for corneal bleb formation and describe our management of this previously unreported complication of trabeculectomy.

Acetazolamide↗

An unusual ectodermal dysplasia with unique eye defects.

We report a 12-year-old boy with dental, auricular, nasolacrimal duct and unique eyelid anomalies as well as cribriform scrotal atrophy. We believe this is the first description of such a case, although many of the features fit within the spectrum of the ankyloblepharon/ectodermal dysplasia/clefting (AEC) syndrome.

Atrophy↗

The achiasmia spectrum: congenitally reduced chiasmal decussation.

AIM: To describe the clinical spectrum of achiasmia, a congenital disorder of reduced relative decussation at the optic chiasm. METHODS: A retrospective case note and patient review of nine children (four boys). Achiasmia was defined by the combination of a characteristic asymmetry of the monocular visual evoked potential (VEP) response to flash and neuroimaging showing reduced chiasmal size. RESULTS: Three of the children had an associated skull base encephalocele with agenesis of the corpus callosum. In two patients achiasmia was associated with septo-optic dysplasia. Three patients had no neuroimaging abnormalities other than reduced chiasmal size and have no known pituitary dysfunction. One child had multiple physical deformities but the only brain imaging abnormality was reduced chiasmal size. CONCLUSIONS: Some children with disorders of midline central nervous system development, including septo-optic dysplasia and skull base encephaloceles, have congenitally reduced chiasmal decussation. Reduced relative decussation may co-exist with overall chiasmal hypoplasia. Children with an apparently isolated chiasmal decussation deficit may have other subtle neurological findings, but our clinical impression is that most of these children function well.

Abnormalities, Multiple↗

Expression of FGFR-2 and FGFR-3 in the normal human fetal orbit.

AIMS: To demonstrate the expression patterns of two fibroblast growth factor receptors (FGFR-2 and FGFR-3) in the normal human fetal orbit. METHODS: 6 microm orbital slide sections were prepared from 12 week old human fetal material obtained within established ethical guidelines. Radioactive in situ hybridisation techniques were used to demonstrate the expression patterns of FGFR-2 and FGFR-3 within these sections. Only one foetus had appropriate orbital sections taken. RESULTS: FGFR-2 was expressed within the extraocular muscles (EOMs) and the optic nerve sheath and to a lesser degree within the orbital periosteal margins and the cranial sutures. FGFR-3 was expressed a lot within the periosteal margins and cranial sutures but not within either the EOMs or the optic nerve sheath. CONCLUSIONS: FGFR-2 and FGFR-3 are differentially expressed within different orbital components. FGFR-2 gene mutations may be responsible for craniosynostotic syndromes such as Crouzon, Pfeiffer, and Apert, while those in the FGFR-3 gene may cause isolated unicoronal synostosis. EOMs may be histologically abnormal in cases of Apert, Pfeiffer, and Crouzon syndromes but not isolated unicoronal synostosis. The pattern of expression of FGFR-2 in the normal human fetal orbit may explain some of the EOM histological findings seen in some cases of Apert, Pfeiffer, and Crouzon syndromes.

Fibroblast Growth Factor 2↗

Ocular and systemic side effects of brimonidine 0.2% eye drops (Alphagan) in children.

INTRODUCTION: Brimonidine 0.2% (Alphagan) is a topical alpha-2 agonist widely used as an antihypertensive. There have been occasional reports of systemic adverse effects in children including apparent central nervous system depression. There are few data available on the overall safety of brimonidine 0.2% in children. METHODS: Computerised pharmacy records were used to identify all children who had been prescribed brimonidine 0.2% in our eye department between August 1999 and June 2001, and their notes were reviewed. RESULTS: In all, 23 patients were identified from pharmacy records and 22 sets of notes were recovered and reviewed. The mean age at commencement of treatment was 8 years (range 0-14 years). In all, 10 (46%) were treated in one eye and 12 (54%) in both. Brimonidine 0.2% was taken for a mean 14 months (range 1 day-75 months). A total of 14 (64%) patients were already taking a topical beta-blocker when brimonidine 0.2% was commenced and a further four (18%) were being treated with another topical hypotensive agent. Of the 22 patients, six (27%) had to stop brimonidine 0.2% because of adverse side effects (two because of local irritation/allergy, two because of tiredness, and two because of fainting attacks). DISCUSSION: Many topical hypotensive agents are not licensed for use in children and few safety data are available. In this study, 18% of children had systemic adverse effects sufficient to necessitate stopping the drug. It is possible that educational impairment may have passed unnoticed in others. Larger studies are required to investigate this further.

Adolescent↗

An ultrasound based classification of periocular haemangiomas.

AIMS: To propose a classification system for periocular haemangiomas based on ultrasound evaluation. METHODS: Retrospective review of ultrasound images from children seen in the authors' unit with periocular haemangiomas. Static ultrasound images from 50 patients with periocular haemangiomas were reviewed as identified from a computerised database. Each haemangioma ultrasound image was classified into three categories: (1) preseptal only; (2) preseptal + extraconal; (3) preseptal + extraconal + intraconal. These were compared with the categories given to each patient at first presentation after dynamic scanning. RESULTS: Classification was possible from the static images in 44 (88%) cases. Of those classified 20 (45%) were preseptal only; 17 (39%) were preseptal + extraconal, and seven (16%) had an additional intraconal component. The classification in all 44 cases was the same as that given at the time of presentation. In the small number of cases which went to surgery or had neuroimaging, the ultrasound classification was confirmed. CONCLUSIONS: Ultrasound classification was not difficult to perform and no child needed sedation or general anaesthesia for this exam. Ultrasound anatomical classification is an important first step in determining appropriate treatment of periocular haemangiomas. The authors present what they believe to be the first such classification.

Child↗

Informing parents of visually impaired children: who should do it and when?

BACKGROUND: Parents of sick or disabled children are likely to be more stressed than parents of non-disabled children and may benefit from being given information about their child's condition and its implications, but the stage at which parents should receive such information and who should provide it has not been fully investigated. The impact of written information on stress levels of parents of visually impaired children, seen in the ophthalmology clinic of a children's hospital, was explored in this study and the question of who parents thought should provide information, and at what stage, was also investigated. METHODS: A longitudinal, experimental intervention study was conducted to compare the effect on perceived stress levels of providing information about the implications of visual impairment to parents. Effects were compared according to the child's age and explored in relation to baseline stress levels. The study included a frequency analysis about parents' knowledge of visual impairment and how it relates to education, and their response to being given written information. RESULTS: The results did not show an effect on levels of parental stress but did find that parents of school age children were more stressed than those of preschool age. Over 80% of participants considered that information was given too late and suggested it should be given soon after diagnosis. Of the controls, 32.6% thought the general practitioner should provide information on education although participants were more likely to expect the hospital to provide it. CONCLUSIONS: The majority of parents would prefer to receive information soon after diagnosis of their child's visual impairment. Most parents do not know who to approach for information on education. Giving them access to patient liaison teams who could advise about the repercussions of visual impairment in children would be beneficial.

Case-Control Studies↗

Visual outcomes and amblyogenic risk factors in craniosynostotic syndromes: a review of 141 cases.

AIMS: To determine the visual outcome and prevalence of amblyogenic risk factors in children with craniosynostotic syndromes. METHODS: The case notes of 141 children seen within the craniofacial unit were reviewed and information retrieved on date of birth, age at first and last examination, cycloplegic refraction at last visit, best corrected visual acuity at last visit, horizontal ocular deviation in primary position at first visit, and alphabet pattern if any. The presence of astigmatism, its magnitude, and orientation of axis were determined. RESULTS: 40.3% of patients had 1 dioptre (D) of astigmatism or greater and, of these, 64% had oblique astigmatism in at least one eye. Anisometropia of 1D or more was found in 18% of patients (age matched normals 3.5%). Horizontal strabismus was found in 70% (38% exotropia, 32% esotropia). Visual outcome results showed 39.8% of patients (45 of 113) had visual acuity of 6/12 or worse in their better eye. CONCLUSION: In the largest study to date a poor visual outcome was shown in children with Crouzon's, Pfeiffer's, Apert's, and Saethre-Chotzen syndromes (39.8% with 6/12 or worse in the better eye) together with significant prevalence of amblyogenic risk factors.

Adolescent↗

Latanoprost in port wine stain related paediatric glaucoma.

AIM: To evaluate the efficacy of latanoprost (Xalatan) as adjunctive therapy in port wine stain related paediatric glaucoma. METHODS: A retrospective non-randomised study. Patients with previous surgical intervention and medical treatment were included. Measurements were recorded from clinic and/or examination under anaesthetic (EUA) visits. A successful outcome was considered to be patients who required no further intervention following initiation of latanoprost, with stable glaucoma factors as well as drop in intraocular pressure. RESULTS: 14 patients and 17 eyes were reviewed in total. The mean age of glaucoma diagnosis was 2.59 years (0.1-5.25 years) and of commencing latanoprost was 6.8 years (1.40-12.90 years). Percentage success at 1 month, 3 months, 6 months, and 1 year was 70.6%, 64.7%, 58.9%, and 47.1%, respectively, of eyes treated which translated to 71.4%, 64.2%, 57.1%, and 50% respectively of patients treated. CONCLUSIONS: A trial of latanoprost as adjunctive therapy in patients with port wine stain related glaucoma may temporise the need for surgery; with 50% of patients being controlled at 1 year follow up. Lack of efficacy was detected as early as 1 month following commencement of treatment.

Adolescent↗

Clinicopathological correlation of congenital corneal opacification using ultrasound biomicroscopy.

AIM: To investigate the correlation between clinical, high frequency ultrasound biomicroscopy (UBM) and, where possible, histological findings in cases of congenital corneal opacification presenting to the departments of ophthalmology, Great Ormond Street Hospital for Children, London, and the Hospital for Sick Children, Toronto, Canada. METHOD: 22 eyes of 13 children (age range 3-225 days) with congenitally opaque corneas were examined. UBM was performed using the ultrasound biomicroscope (Allergan-Humphrey). All eyes underwent penetrating keratoplasties (PKP) except five. The host corneas were all sent for histological examination. RESULTS: The final diagnosis in our series was Peters' anomaly in nine cases (70%), corneal dystrophy in two cases (15%), and sclerocornea in two cases (15%). The UBM findings changed the clinical diagnosis in five cases (38%). In these five cases histology was available in four and confirmed the UBM diagnosis in each case. In no case of the 13 where histology was available did it contradict the UBM findings. In two cases a hypoechoic region in the anterior stroma was seen on UBM which correlated histologically with absent Bowman's layer and oedema. In two cases UBM revealed aniridia and in one, congenital aphakia, which was not apparent clinically. CONCLUSION: UBM examination is not only very useful in evaluating the clinical diagnosis in congenital corneal opacification, it also acts as a preoperative guide in cases undergoing PKP by detecting keratolenticular and iridocorneal adhesions and other ocular abnormalities such as aniridia and congenital aphakia. In all cases where PKP was performed the UBM diagnosis was confirmed histologically. The clinical diagnosis was incorrect in five cases. This has important implications in studies of phenotype/genotype correlation of congenital corneal opacification.

Corneal Opacity↗

Values of electroretinogram responses according to axial length.

Accurate interpretation of electroretinograms (ERGs) requires knowledge of effects of axial myopia on ERG responses. Our purpose was to derive expected changes of ERG responses according to axial length, to stimulus conditions that conform to the International Society for Clinical Electrophysiology of Vision (ISCEV) Standard for Electroretinography. ERGs from 60 subjects were recorded. The subjects were assigned to one of three groups according to the level of myopia. Thirty-three subjects had high myopia (-6.00 D to -14.50 D; mean age, 31 years), eight had mild myopia (-3.00 D to -5.00; mean age, 28 years), and 19 had a small refractive error (+0.75 D to -2.75 D; mean age, 27 years). No subjects had myopic retinopathy. Stimulus-response curves were fitted to dark-adapted b-wave amplitudes and maximum amplitude and semi-saturation constants derived. Axial lengths, measured with A scan ultrasound, ranged from 22.2 mm to 30.0 mm. Analysis of variance and post hoc t-tests revealed significant difference between subjects with high myopia and subjects with small refractive error for ERG amplitude data. There were no significant differences between the three groups for implicit times, the ratio of b- to a-wave and semi-saturation constant. There is linear reduction in the logarithmic transform of ERG amplitude with increasing axial length, related more to axial length than refractive error. We provide relative slope and intercept values, allowing labs to derive expected ERG amplitudes according to axial length. These derivations are valid for persons with no retinopathy.

Adolescent↗

Ultrasound biomicroscopy of the eye in cystinosis.

OBJECTIVE: To describe the ocular ultrasound biomicroscopy (UBM) findings in patients with cystinosis. METHODS: Six patients with infantile nephropathic cystinosis, aged 16 to 25 years, and 6 controls (matched for age and spherical refractive error) were examined clinically and with UBM. Scleral reflectivity, corneal and iris thickness, central anterior chamber depth, angle width, trabecular meshwork to ciliary process distance, and ciliary sulcus width were measured. RESULTS: No patient had glaucoma or posterior synechiae, but all had crystals in the trabecular meshwork apparent with gonioscopy. Using UBM, the cornea and iris appeared similar in both groups, but the scleral reflectivity was increased in patients (P =.003). The angle was narrower in patients (mean +/- SD, 20 degrees +/- 7 degrees ) than controls (31 degrees +/- 5 degrees, P<. 001). The anterior chamber was shallower in patients (2556 +/- 197 microm) than controls (2968 +/- 284 microm, P<.001). The ciliary sulcus was closed or narrow in all patients (83 +/- 112 microm) compared with controls (339 +/- 135 microm, P<.001), with a reduction in the trabecular meshwork to ciliary process distance. CONCLUSIONS: This report of ocular UBM findings in cystinosis demonstrated narrowing of the angle and a ciliary body configuration similar to that reported for plateau iris syndrome. Gonioscopy demonstrated crystals in the trabecular meshwork. These findings may explain the predisposition of these patients to glaucoma.

Adolescent↗