Characteristics and utility of combined duplex color-coded ultrasonography in the cervical rotational position with head MRI and MRA in the differential diagnosis of apogeotropic direction-changing positional nystagmus

Objective:To determine whether cervical ultrasonography,magnetic resonance imaging(MRI),and magnetic resonance angiography(MRA)are useful in the differential diagnosis of etiology and understanding the pathophysiology in cases of apogeotropic direction-changing positional nystagmus(DCPN).Methods:Thirty patients with apogeotropic DCPN were classified into 11 cases of central disease,seven cases of mixed central and peripheral disease,and 12 cases of peripheral disease by differential diagnosis based on various balance function,neuro-otological,and imaging tests.Cervical ultrasonography using the cervical rotation method and MRI and MRA of the head and neck were performed in most patients with apogeotropic DCPN.We reviewed the presence of abnormal imaging findings according to the disease etiology.Results:Of the 30 patients with apogeotropic DCPN,23 showed vascular abnormalities or central lesions on imaging.Vascular lesions were found in six of the 12 patients with peripheral disease.Cervical ultrasonography with cervical rotation detected blood flow disturbance in the vertebral artery in eight patients in whom the disturbance could not be detected by MRI or MRA of the head and neck.Discussion:We hypothesize that the causative disease of apogeotropic DCPN may be strongly associated with circulatory insufficiency of the vertebrobasilar and carotid arteries,and that impaired blood flow in these vessels may affect peripheral vestibular and central function.In patients with apogeotropic DCPN,examinations of vestibular function,central nervous system symptoms,and brain hemodynamics are valuable for differential diagnosis.

Acute isolated vertigo with vertical up-beating nystagmus: A rare case of nucleus intercalatus of Staderini ischemia

The role of intercalatus nucleus of Staderini(INS),the most caudal of the perihypoglossal nuclei,is much debated.Last research seems to suggest that this nucleus plays a role as a vertical eyes movements integrator.The few clinical reports present in the literature that describe isolated lesions of the INS have described patients presenting in acute with up-beating vertical spontaneous nystagmus.Isolated acute lesion of INS is,in fact,much rare,and,without other neurological signs,is exceptional.We present a case of acute isolated vertigo with no other neurological signs or symptoms,due to INS ischemia provoked by vertebral artery stenosis.The patient presented with spontaneous vertical up-beating nystagmus that showed at videonystagmographic recording,a clear exponential decay of angular slow-phase velocity,that is considered a typical sign of neural integrator impairment.This case seems to represent a further confirm that INS is part,as a vertical-to-position neural integrator,of the neural circuit controlling the vertical eyes movements.

A new measure of nystagmus acuity

AIM: To construct a new visual acuity measuring function for congenital nystagmus(CN) patients by studying the relationships between acuity,velocities and positions of the eye. ·METHODS: After assessing the relationship between acuity,movement velocities and positions of the eye separately,a new function,which we call the automated nystagmus acuity function(ANAF),was constructed to measure the visual acuity of CN patients. Using a high-speed digital video system working at 500 frames per second,each eye was calibrated during monocular fixation. Twenty-six recorded nystagmus data were selected randomly. Using nystagmus waveforms,the best vision position(foveation period) and visual acuity were analyzed in three groups of subjects,and then all outputs were compared with the well-known expanded nystagmus acuity function(NAFX) and ANAF. Standard descriptive statistics were used to summarize the outputs of the two programs. ·RESULTS: Foveation periods were brief intervals in the CN waveform when the image was on or near the fovea and eye velocity was relatively slow. Results showed good visual acuity happened during the period when velocity was low and the eye position was near the zero position,which fitted the foveation periods. The data analyzed with NAFX and ANAF had a correlation coefficient of 0.934276,with an average error of-0.00973. · CONCLUSION: The results from ANAF and NAFX analyses showed no significant difference. The NAFX manually identifies foveation eye positions and produces accurate measurements. The ANAF,however,can be calculated simply using the factors eye position andvelocity,and it automatically calculates the ANAF without the need to manually identify foveation eye positions.

Design and Efficacy of Surgery for Horizontal Idiopathic Nystagmus with Abnormal Head Posture and Strabismus

The design and efficacy of surgery for horizontal idiopathic nystagmus （HIN） with abnormal head posture and strabismus were investigated. Different surgical procedures were selected according to the angle of head turn in 44 cases of HIN with abnormal head posture and strabismus. For patients with a head turn of 15° or less, the Anderson procedure was used; the yoke muscles were recessed upon slow-phase. For patients with a head turn between 15° and 25°, the surgery was designed as a Kestenbaum 5-4-4-5 procedure. For patients with a head turn of 25° or more, the surgery was designed as a Parks 5-8-6-7 procedure. The surgery to correct the abnormal head posture was performed on the fixating eye while that to correct the deviation was then performed on the non-fixating eye at the same time. The amount of surgery of the horizontal rectus muscles on the nonfixating eye was sum of the angle of head turn and the degree of deviation, which was calculated as follows： recession/resection amount of medial and lateral rectis/2×5=angle of head turn±degree of deviation. The results showed as follows： （1） Visual acuity： the visual acuity in the primary ocular position increased two lines or more in 35 patients, accounting for 79.55%. Nine patients had no or only one-line improvement, accounting for 20.45% of the entire study population; （2） The degree of deviation in the primary ocular position： 37 cases had a normal primary ocular position or the degree of deviation ≤8△ after surgery, accounting for 84.09%. Six patients had a residual degree of deviation of 8△―15△, accounting for 13.64%. One patient had a residual degree of deviation 〉20△, accounting for 2.27% of the patients examined; （3） Abnormal head posture： 34 patients had a normal head posture or a head turn of less than 5°, accounting for 72.27%. Eight patients had a residual head turn of 5°―15°, accounting for 18.18%. Two patients had a head turn of 15°― 25°, accounting for 4.55%. It was concluded that different surgical procedures based on the angle of head turn and the relationship between deviation and null zone can eliminate anomalous head posture, correct deviation, and improve vision acuity in the primary ocular position simultaneously.

Clinical features of strabismus and nystagmus in bilateral congenital cataracts

AIM：To evaluate the prevalence,clinical features,and the factors affecting onset of strabismus and nystagmus in patients with bilateral congenital cataracts.METHODS：This study evaluated 116 eyes of 58 patients who underwent lens removal for the treatment of bilateral congenital cataracts between January 1999 and January 2011.The presence and type of strabismus and nystagmus were determined before and after surgery.Type of strabismus and final visual acuity were compared in patients with and without nystagmus.Patients were divided into three groups（orthotropia/orthotropia,orthotropia/strabismus,and strabismus/strabismus） according to their preoperative and postoperative ocular alignment.Age at cataract surgery and associations of nystagmus and primary intraocular lens（IOL） implantation with strabismus were analyzed.RESULTS：Six patients（10.3%） had strabismus preoperatively and an additional 11（19.0%） developed postoperative strabismus.Exotropia was more common than esotropia both preoperatively and postoperatively.Eighteen patients（31.0%） had postoperative nystagmus,with sensory nystagmus being the most common type.Of the 18 patients with nystagmus,10 had strabismus,with exotropia being more common than esotropia.Postoperative visual acuity was poor in patients with nystagmus.Age at cataract surgery and rate of primary IOL implantation were significantly lower,and postoperative nystagmus was more common,in the orthotropia/strabismus group than in the other two groups.CONCLUSION：Exotropia and sensory nystagmus are common in patients with bilateral congenital cataracts.Age at cataract surgery and rate of IOL implantation are lowerand nystagmus more common in patients with postoperative onset of strabismus.Nystagmus is associated with poor visual prognosis.

A novel nonsense mutation of GPR143 gene in a Korean kindred with X-linked congenital nystagmus

Dear Editor,I am Dr.Ungsoo Samuel Kim.from Kim＇s Eye Hospital,Konyang University,Seoul,Korea.I write to present a novel mutation of GPR143 in Korean patients with X-linked congenital nystagmus by using exome sequencing.Congenital nystagmus is an inherited ocular disorder that can occur as an X-linked condition.

Spectral-domain optical coherence tomography in patients with congenital nystagmus

AIM: To study macular features in patients with congenital nystagmus and to assess the utility of spectral-domain optical coherence tomography (SD-OCT) in nystagmus. METHODS: The macular areas of 51 outpatients with congenital nystagmus were examined using SD-OCT. Morphological changes in the retinal layers of the macular area were analysed. RESULTS: Macular images were successfully obtained with SD-OCT from 50 (98%) patients. Patients with ocular albinism mainly have macular hypoplasia, abnormal foveal depression, and increased foveal thickness with persistence of an inner nuclear layer, an inner plexiform layer, a ganglion cell layer and a nerve fiber layer. Macular morphology similar to albinism was observed in three patients with idiopathic macular hypoplasia. The OCT findings of cone dystrophy included unclear, disrupted or invisible photoreceptor outer segment/inner segment in the fovea; fusion, thickening and uneven reflection of the outer segment/inner segment with external limiting membrane. Some patients with congenital idiopathic nystagmus showed normal macular morphology and structure, and others showed indistinct macular external limiting membrane reflection. CONCLUSION: SD-OCT is an effective and reliable method to detect the macular morphology of congenital nystagmus patients. This technique has diagnostic value in particular for patients with macular hypoplasia and cone cell dystrophy with no distinct abnormality on fundoscopy.

Acute thrombosis of the carotid artery associated with positional nystagmus at multiple planes

Objective:An acute onset central pathology without any clear neurological symptoms may mimic peripheral vestibular problem in an emergency setting.A 54-year-old man suddenly developed dizziness without any cranial nerve symptoms,paresis,cerebellar signs or sensory disturbances except upbeat positional nystagmus at multiple provoked positions which alerted for a possible acute central pathology.Findings:An instantaneous magnetic resonance imaging and angiography studies further showed obstruction of the left internal carotid artery above the bifurcation.The patient’s subsequent prognosis was consistent with good recovery following anti-coagulant therapy.A follow-up MRI and angiography showed resolution of thrombosis.Conclusion:It should be kept in mind that positional nystagmus is likely to occur in central pathologies.Differentiation between benign paroxysmal positional vertigo and central positioning nystagmus is critical.

Direction-fixed positional nystagmus following head-roll testing:how is it related with a vestibular pathology?

Objective:The goal of this study is to analyze the clinical view of patients with direction-fixed positional nystagmus(DFPN)following head-roll maneuver.Methods:Sixty patients with DFPN were reviewed retrospectively.Patients were categorized into 3 groups according to the direction of nystagmus based on rotation side.Associated problems were documented,and cumulative data were compared between groups.One-way analysis of variance(ANOVA test)was used for statistical analysis(P<0.05).Results:Thirty-three patients(55%)had stronger nystagmus beating towards the direction of head-roll(Group-A).Three patients developed geotropic LC-BPPV.Fourteen patients had inner ear disease.Sixteen patients(27%)had stronger nystagmus beating against the direction of head roll(Group-B).Nine patients had inner ear disease.None of the patients tested with head-shaking had change of direction of nystagmus.Eleven patients(18%)had DFPN with equal velocity during right or left head-roll maneuver(Group-C).Of those,nine patients had inner ear disease.None of the patients had change of direction of nystagmus.Comparison of the incidence of associated problems(migraine,vestibular neuronitis,Meniere’s disease etc.)in each group was not statistically significant(P˃0.05).Conclusion:Patients with DFPN should be followed for a possibility of vestibular pathology since vestibular problem was documented for more than half of the patients in the follow-up.On the other hand,DFPN could be related with a temporary reason(thermal,physical or drug effect etc.)in some patients who do not exhibit any associated disease.Head-shaking testing is recommended to expose the lateral canal BPPV.But the incidence is low.

Benign paroxysmal positional vertigo with congenital nystagmus: A case report

BACKGROUND Benign paroxysmal positional vertigo(BPPV)is a form of temporary vertigo induced by moving the head to a specific position.It is a self-limited,peripheral,vestibular disease and can be divided into primary and secondary forms.Congenital nystagmus(CN),an involuntary,rhythmic,binocular-symmetry,conjugated eye movement,is found at birth or within 3 mo of birth.According to the pathogenesis,CN can be divided into sensory-defect nystagmus and motordefect nystagmus.The coexistence of BPPV and CN is rarely seen in the clinic.CASE SUMMARY A 62-year-old woman presented to our clinic complaining of a 15-d history of recurrent positional vertigo.The vertigo lasting less than 1 min occurred when she turned over,sometimes accompanied by nausea and vomiting.Both the patient and her father had CN.Her spontaneous nystagmus was horizontal to right;however,the gaze test revealed variable horizontal nystagmus with the same degree when the eyes moved.The patient’s Dix-Hallpike test was normal,except for persistent nystagmus,and the roll test showed severe variable horizontal nystagmus,which lasted for about 20 s in the same direction as her head movement to the right and left,although the right-side nystagmus was stronger than the left-side.Since these symptoms were accompanied by nausea,she was diagnosed with BPPV with CN and treated by manual reduction.CONCLUSION Though rare,if BPPV with CN is correctly identified and diagnosed,reduction treatment is comparably effective to other vertigo types.

Scaling Properties of Optokinetic Nystagmus Amplitude Sequence

Optokinetic nystagmus (OKN) is rhythmic eye movements, back and forth, with a slow and fast phase when the eyes are presented for full-field visual stimulus. OKN was recorded in a healthy subject for four conditions, stripes moving 30°/s left and right and 60°/s left and right. In this paper, surrogate data analysis was applied to test the Hurst exponents for increasing time horizons for the integrated OKN amplitude sequences statistically against 100 shuffled sequences (i.e., the serial dependency of the original data sequences is broken by changing the order of the sequence). The result shows that the pattern of the OKN amplitude sequence scales statistically different (p < 0.01) compared to random permutations of the same numbers for scaling shorter than 16 nystagmus components (slow and fast phases) for all four test conditions.

Surgical Treatment of a Patient with See-Saw Nystagmus (SSN): Case Report

Background: Acquired See-saw Nystagmus (SSN) is a rare form of nystagmus characterized by elevation and intorsion of one eye with synchronous depression and intorsion of the contralateral eye in the first half cycle, followed by a reversal in the direction of the movements during the next half cycle. We herein report a case of a 47-year-old woman with a 3-year history of constant diplopia as a consequence of multiple neurosurgical interventions due to hemorrhage from a cavernous angioma located in the subthalamic region. She also had a history of major depressive disorder and ulcerative colitis. The patient underwent a surgical intervention with a 5 mm bilateral recession of the superior and inferior rectus muscles. Five years after surgery, the patient reported less recurrent and prominent episodes of transient horizontal deviation with horizontal diplopia, with a prevalence of well-being and comfort.

Clinical Characteristics of Nystagmus in Albinos Living in Libreville

Introduction: Nystagmus is a static ocular disorder characterized by an oscillatory, involuntary and rhythmic movement of eyes. In Libreville, no data on the subject is available. The purpose of this study is to describe clinical characteristics of nystagmus in albinos living in Libreville. Methods: This is a descriptive, cross-sectional study including 43 albinos with oculocutaneous albinism and nystagmus during the period from February 01, 2017 to February 01, 2018. Variables studied were age, sex, visual acuity, objective refraction, characteristics of the nystagmus including morphology, direction, intensity and associated signs such as stiff neck and squint. Results: The mean age was 21.2 ± 17 years with a female-dominated ratio of 0.53. The visual acuity from afar without correction (AVLSC) was less than 3/10 in 88.4% of the cases. The most common ametropia was astigmatism in 51.2% of cases. Nystagmus was present in all albinos. The spring type was found in 69.7% of cases. The direction was horizontal in 67.4% of the cases and rotary in 32.6% of the cases. The intensity was moderate in 55.8% of cases. The blocking position was the primary near vision position in 69.7% of the cases. Nystagmus was associated with a stiff neck in 28% of the cases and strabismus in 48.8% of the cases. Conclusion: The albinos nystagmus living in Libreville is of the spring type, horizontal direction, of moderate intensity and calmed in the primary position in near vision.

Botulinum Toxin for the Treatment of Nystagmus Associated with Exotropia

Purpose: Nystagmus can severely impact the visual function, lifestyle and quality of life of patients. Patient with Nystagmus may assume an abnormal compensatory head position and it can result in posture disorders. Botulinum toxin is an important treatment for much pathology of the eye, in particular for blepharospasm, strabismus and nystagmus. The mechanism of action is to prevent lease of acetylcholine in the neuromuscular junction getting the neuromuscular blockade and transient flaccid paralysis. The objective of this work is to evaluate the efficacy of botulinum toxin injection in patients with Nystagmus. Methods: n. 6 patients, (3 females and 3 males) aged 17 - 35 years, exhibiting exotropia (XT) associated with Nystagmus received an injection of Botulinum Toxin A Dysport (Ipsen) in the Lateral Muscles of each eye with a 27-gauge retrobulbar needle. Patients underwent an orthoptic and ophthalmic eye exam before and after surgery. Results: A significant reduction of the nystagmus in primary position was reported in all patients;the abnormal position of the head was noticeably reduced. Side-effects were limited and well tolerated by the patients. Conclusion: Botulinum toxin injection is a valuable treatment of Nystagmus associated with exotropia.

Smith-Kingsmore syndrome with nystagmus as the initial symptom

Background Smith-Kingsmore syndrome(SKS)is a rare autosomal dominant disorder caused by de novo mutations of gene MTOR in most cases and germline mosaicism in a few cases.The first case of SKS was reported in 2013.The incidence of SKS remains unknown.The clinical manifestations of SKS are diverse,and common features are macrocephaly,intellectual disability,and seizures.Some patients with SKS have special facial features.Case presentation The case was a 5-month-old baby girl,who was admitted to the hospital for nystagmus,delayed development for 2 months,and intermittent convulsions for 2 days.The patient had a head circumference of 42 cm(+2SD),and showed facial deformity,low limb muscle tension,large areas of pigmentation,as well as mosaic patchy and strip-like pigment loss in her trunk and limbs.Meanwhile,her development was lagging behind peers.Physical examination did not reveal other abnormalities.She was diagnosed with SKS based on whole-exome sequencing combined with clinical symptoms and signs.She successively received treatment with adrenocorticotropic hormone,methylprednisolone sodium succinate,topiramate,levetiracetam,and zonisamide to reduce the number of convulsions in a short time,but drug resistance appeared thereafter.After combined treatment with multiple antiseizure medications,the patient still had seizures,but the amplitude of limb movement during the seizures was reduced compared to that before treatment.Conclusions This case expanded the phenotypic spectrum of SKS for diagnosis.We also review the related literature to promote the awareness,diagnosis,clinical management,and follow-up of SKS patients with MTOR mutations.

Comparisons of Supine Roll Test and Alternative Positional Tests in HC-BPPV Lateralization

Objective The purpose of the study was to evaluate the efficiency of the supine roll test(SRT)and alternative positional tests(APTs)including the bow and lean test(BLT),pseudo-spontaneous nystagmus(PSN),and lying down nystagmus(LDN)to identify the affected side in horizontal canal benign paroxysmal positional vertigo(HC-BPPV).Methods In our prospective study,we performed a testing profile(PSN,BLT,LDN,SRT)on 59 HC-BPPV patients using videonystagmography.We compared the accuracy and sensitivity of these tests in HC-BPPV lateralization.Data from 30 healthy patients were collected as the control group.Results When performing positional tests,the elicited nystagmus coinciding with Ewald’s second law was defined as a“positive response”.In 44 patients with geotropic nystagmus,the rates of positive response in LDN,PSN,and BLT were 22/44(50%),19/44(43%),and 18/44(41%),respectively,while in 15 patients with apogeotropic nystagmus,the positive response rates of these three tests were 10/15(66.7%),9/15(60%),and 4/15(27.00%),respectively.The sensitivity of LDN(54.38%)was higher than that of PSN(47.37%)and BLT(38.60%)but lower than that of SRT(89.47%).Notably,the accuracy rate of PSN(71.8%)was higher than that of the other APTs.In 6 patients with symmetrical nysgtamus during the roll test,5 patients showed a positive response in both LDN and BLT(83.34%),whereas 4 patients showed a positive response in PSN(66.67%).Conclusion All positional tests are helpful for determining the affected side of HC-BPPV,but SRT carries the highest accuracy of lateralization followed by PSN.

Factors associated with strabismus after cataract extraction and primary intraocular lens implantation in congenital cataracts

AIM:To evaluate factors associated with the development of strabismus after cataract extraction and primary intraocular lens implantation.METHODS:The medical records of 122 patients,aged1.5mo to 9y,who had undergone cataract extraction with primary intraocular lens implantation between January1993 and August 2011 were reviewed.Fourteen patients(17 eyes)with strabismus before cataract surgery were excluded.Patients were divided into those with congenital bilateral cataracts(64 patients,128 eyes)and those with unilateral cataracts(44 patients,44 eyes).The associations between the development of strabismus and age at cataract surgery,pre-and post-cataract extraction corrected distance visual acuity(CDVA),interocular CDVA difference,nystagmus,surgical method,and secondary cataract were evaluated.RESULTS:Factors significantly associated with the development of strabismus included age at cataract surgery(≤1y),preoperative mean CDVA≤20/100,presence of nystagmus in the bilateral cataract group and postoperative interocular CDVA difference】20/70 in the unilateral group.Postoperative CDVA≤20/100 and preservation of posterior capsule,and presence of secondary cataract were significant factors in both groups.CONCLUSION:Children with congenital cataracts should be monitored carefully after cataract surgery for the development of strabismus,especially when they underwent surgery at age≤1y,and they have nystagmus,large postoperative interocular CDVA difference,poor preoperative and postoperative CDVA,preservation of the posterior capsule,or secondary cataract.

Light Cupula:To Be Or Not to Be?

Benign paroxysmal positional vertigo(BPPV)represents the most common form of positional vertigo.It is caused by dislodged otoconia that freely float in the semicircular canals(canalolithiasis)or attach to the cupula(cupulolithiasis).A cupulolithiasis-type(or a heavy cupula-type)of BPPV implicating the lateral semicircular canal(LSCC)exhibits persistent ageotropic direction-changing positional nystagmus(DCPN)in a head-roll test.However,in some cases,unlike any type of BPPV,persistent geotropic DCPN cannot be explained by any mechanisms of BPPV,and don’t fit the current classifications.Recently,the notion of light cupula has been introduced to refer to the persistent geotropic DCPN.In this study,we looked at the clinical features of light cuplula and discussed the possible mechanisms and therapeutic strategies of the condition.The notion of light cupula is a helpful addition to the theory of peripheral positional vertigo and nystagmus.

A 7-Year-Old Boy with Light Cupula of the Horizontal Semicircular Canal

Report of childhood positional vertigo is very rare. We present a 7-year-old boy who revealed persistent direction-changing geotropic positional nystagmus. In the supine position, horizontal nystagmus toward the left continued as long as the position was maintained. However, it ceased when the head was turned to the right side by 45°. With greater head turn (right-ear-down), nystagmus toward the right lasted for more than 1 minute. In the left-ear-down position, horizontal nystagmus toward the left occurred and lasted for more than 1 minute. After the disappearance of positional nystagmus, we detected canal paresis of the right ear by caloric test. We considered that the pathophysiology of the persistent type of geotropic nystagmus is a result of light debris cupulolithiasis of the horizontal canal.

Novel variant syndrome associated with congenital hepatic fibrosis

Congenital hepatic fibrosis is part of many different malformation syndromes, of which oculo-encephalohepato-renal syndrome is the most common. These syndromes largely overlap, and so accurate classification of individual patients may be difficult. We present herein three syndromic siblings who were products of a consanguineous marriage. We investigated in detail at least six organ systems in these patients, namely the liver, brain, eye, kidneys, skeleton, and gonads. The common features observed in these three cases were congenital hepatic fibrosis, retinitis pigmentosa, truncal obesity, rotatory nystagmus, mental retardation, advanced myopia, and high-arched palate. The clinical dysmorphology in these patients was distinct and lacked the major features of the known syndromes associated with congenital hepatic fibrosis. Although some features of these presented cases are similar to those found in Bardet-Biedl syndrome(BBS), the absence of some major criteria of BBS(polydactyly, renal abnormality, and hypogonadism) suggests that this may be a new syndrome. All three patients remain under follow-up in the departments of Gastroenterology, Ophthalmology, and Neurology at Hacettepe University.