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PURPOSE: To investigate the theoretical hydrodynamic effects of a single or a double XEN 45 Gel Stent (XEN45) implant in glaucomatous eyes. METHODS: A prospective non-randomized clinical study on 63 glaucomatous eyes of 63 patients. The preoperative intraocular pressure (IOP) values after 14 days of medical therapy washout was correlated to the postoperative IOP values 7 and 45 days after the implant of a XEN45. A mathematical model based on the Hagen-Poiseuille law was designed to assess the residual aqueous humor outflow (AHO) facility in glaucomatous eyes in function of the postoperative IOP reduction. Using XEN45 as unit of measurement, we transformed through equations the residual preoperative AHO in XEN45 equivalent in order to establish theoretical number of stents needed to reach the target IOP. RESULTS: The mean preoperative washout IOP was 28.9 ± 5.4 mmHg, after 7 and 45 days the mean postoperative IOP was 12.6 ± 4.3 and 15.3 ± 4.4 mmHg, respectively (p < 0.001). A significant positive correlation was found between preoperative and postoperative IOP values. We obtained a mathematical relationship to estimate the theoretical number of XEN45 stents needed to reach the target IOP. CONCLUSION: The basal IOP (after medical therapy washout) is a predictive factor for the surgical success after a XEN45 implant. Establishing the residual preoperative AHO it is possible to predict the theoretical number of stents to implant. A double XEN45 implant could be considered a possible further tool to reach the target IOP in patients with severe AHO deficiency.

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Implantes de Drenaje de Glaucoma , Glaucoma de Ángulo Abierto , Glaucoma , Humanos , Diseño de Prótesis , Estudios Prospectivos , Resultado del Tratamiento , Glaucoma/cirugía , Presión Intraocular , Stents , Estudios Retrospectivos

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The pathophysiology of vision loss and loss of visual field in patients with idiopathic intracranial hypertension with papilloedema is not fully understood. Although elevated CSF pressure induces damage to the optic nerve due to stasis of axoplasmic flow, there is no clear relationship between the severity of papilloedema and CSF pressure. Furthermore, there are cases of purely unilateral papilloedema and cases without papilloedema despite significantly elevated intracranial pressure as well as papilloedema that can persist despite a successfully lowered intracranial pressure. We hypothesize that at least in some of such cases, in addition to purely pressure-induced damage to the optic nerve, the biochemical composition of the CSF in the subarachnoid space surrounding the orbital optic nerve may play a role in the pathogenesis of vision loss. In this retrospective study, we report on lipocalin-type prostaglandin D synthase concentrations in the CSF within the perioptic and lumbar subarachnoid space in 14 patients with idiopathic intracranial hypertension (13 females, mean age 45 ± 13 years) with chronic persistent papilloedema resistant to maximum-tolerated medical therapy and visual impairment. CSF was collected from the subarachnoid space of the optic nerve during optic nerve sheath fenestration and from the lumbar subarachnoid space at the time of lumbar puncture. CSF was analysed for lipocalin-type prostaglandin D synthase and the concentrations compared between the two sites using nephelometry. The mean lipocalin-type prostaglandin D synthase concentration in the perioptic subarachnoid space was significantly higher compared with the concentration in the lumbar subarachnoid space (69 ± 51 mg/l without correction of serum contamination and 89 ± 67 mg/l after correction of serum contamination versus 23 ± 8 mg/l; P < 0.0001, Mann-Whitney U-test). These measurements demonstrate a change and imbalance in the biochemical environment of the optic nerve. Its possible effect is discussed.

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OBJECTIVE: To report on the lipocalin-type prostaglandin D synthase (L-PGDS) concentrations in the cerebrospinal fluid (CSF) of the perioptic and lumbar subarachnoid space (SAS) in patients with radiologically proven optic nerve (ON) sheath compartmentation presenting as normal-tension glaucoma (NTG). METHODS: Retrospective biochemical analysis of CSF in thirteen patients with ON sheath compartmentation presenting as NTG (four females, mean age 70±8 years). CSF was sampled from the SAS of the ON during ON sheath fenestration for ON sheath compartmentation and from the lumbar SAS at the time of lumbar puncture. Nephelometry was used for the quantification of L-PGDS and albumin concentration. Albumin was measured in order to assess the amount of contamination with serum in the CSF samples taken from the ON SAS. Main outcome measures were L-PGDS concentrations in the CSF of the perioptic and lumbar SAS. RESULTS: Mean L-PGDS concentration was 24±8 mg/L in the lumbar SAS compared to 33±27 mg/L without correction of serum contamination and 45±39 mg/L after correction of serum contamination in the perioptic SAS. The difference between the lumbar and the perioptic SAS was statistically significant (P=0.0047 without correction of serum contamination, P=0.0002 with correction of serum contamination; Mann-Witney U-test). CONCLUSION: This study demonstrates a concentration gradient of L-PGDS levels within the CSF with a statistically significant higher concentration in the compartmentalized perioptic SAS compared to that in the lumbar SAS. Biochemical changes in the perioptic SAS might be involved in the pathophysiology in NTG patients with ON sheath compartmentation.

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BACKGROUND: Adult-attention-deficit-hyperactive-disorder (ADHD) is often unrecognized condition. FMRI examination along with neuropsychological testing might strengthen the diagnosis. We hypothesized that ADHD-adults with and without medication would show different fMRI pattern compared to healthy controls while testing tasks of motor inhibition and cognitive switching. METHODS: 45 subjects in three age-matched groups: (1) controls, (2) ADHD-adults under medication (ADHD+) and (3) medication-naïve adults with ADHD (ADHD-) underwent fMRI and neuropsychological testing. Group analysis and population-based statistics were performed. RESULTS: DTVP-A, intellectual ability as well as attention capability, visual-perceptual and visual-motor abilities showed no significant differences between the groups. However, fMRI revealed statistically significant differences between the ADHD+, ADHD- and control groups on tasks of motor inhibition and cognitive switching on adults in bilateral fronto-striatal brain regions, inferior fronto-frontal, fronto-cingulate and fronto-parietal networks as well as in the parietal lobe (p < 0.05). CONCLUSIONS: fMRI offers the potential to differentiate between the ADHD+, ADHD- and control groups. FMRI possibly opens a new window for monitoring the therapeutic effect of ADHD medication. TRIAL REGISTRATION: NCT02578342, registered at August 2015 to clinical trial registry ( https://ichgcp.net/clinical-trials-registry/NCT02578342 ).

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Trastorno por Déficit de Atención con Hiperactividad/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Adulto , Atención/efectos de los fármacos , Atención/fisiología , Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Trastorno por Déficit de Atención con Hiperactividad/fisiopatología , Encéfalo/efectos de los fármacos , Encéfalo/fisiopatología , Estudios de Casos y Controles , Cognición/efectos de los fármacos , Cognición/fisiología , Cuerpo Estriado/diagnóstico por imagen , Cuerpo Estriado/efectos de los fármacos , Diagnóstico Diferencial , Lóbulo Frontal/diagnóstico por imagen , Lóbulo Frontal/efectos de los fármacos , Humanos , Inteligencia/efectos de los fármacos , Inteligencia/fisiología , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Lóbulo Parietal/diagnóstico por imagen , Lóbulo Parietal/efectos de los fármacos , Desempeño Psicomotor/efectos de los fármacos , Desempeño Psicomotor/fisiología , Tiempo de Reacción , Percepción Visual/efectos de los fármacos , Percepción Visual/fisiología , Adulto Joven

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Purpose: To examine the cerebrospinal fluid (CSF) dynamics along the entire optic nerve in patients with idiopathic intracranial hypertension (IIH) and papilledema by computed tomographic (CT) cisternography. Methods: Retrospective analysis of CT cisternographies in 16 patients with a history of IIH and papilledema (14 females and 2 males, mean age: 49 ± 16 years). Contrast loaded CSF (CLCSF) was measured in Hounsfield Units (HU) at three defined regions of interest (ROI) along the optic nerve (orbital optic nerve portion: bulbar and mid-orbital segment, intracranial optic nerve portion) and additionally in the basal cistern. The density measurements in ROI 1, ROI 2, and ROI 3 consist of measurements of the optic nerve complex: optic nerve sheath, CLCSF filled SAS and optic nerve tissue. As controls served a group of patients (mean age: 60 ± 19 years) without elevated intracranial pressure and without papilledema. Results: In IIH patients the mean CLCSF density in the bulbar segment measured 65 ± 53 HU on the right and 63 ± 35 HU on the left side, in the mid-orbital segment 68 ± 37 HU right and 60 ± 21 HU left. In the intracranial optic nerve portion 303 ± 137 HU right and 323 ± 169 HU left and in the basal cistern 623 ± 188 HU. Within the optic nerve the difference of CLCSF density showed a highly statistical difference (p < 0.001) between the intracranial optic nerve portion and the mid-orbital segment. CLCSF density was statistically significantly (p < 0.001) reduced in both intraorbital optic nerve segments in patients with IIH compared to controls. Conclusions: The current study demonstrates reduced CLCSF density within the orbital optic nerve segments in patients with IIH and papilledema compared to 12 controls without elevated intracranial pressure and without papilledema. Impaired CSF dynamics could be involved in the pathophysiology of optic nerve damage in PE in IIH.

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PURPOSE: To investigate the cerebrospinal fluid (CSF) dynamics along the entire optic nerve (ON) in patients with normal-tension glaucoma (NTG). METHODS: Retrospective analysis of computed tomographic (CT) cisternographies in Caucasian patients with NTG. Fifty-six patients (99 of 112 eyes) fulfilled the diagnostic criteria of NTG and underwent CT-cisternography. Twelve subjects without NTG (24 eyes) served as controls. Contrast-loaded cerebrospinal fluid (CLCSF) density measurements in Hounsfield units (HU) were performed at four defined regions along the ON and in the basal cistern. RESULTS: In NTG patients, the mean density CLCSF in the bulbar segment measured 76 ± 49 HU right and 88 ± 74 HU left, in the mid-orbital segment 117 ± 92 HU right and 119 ± 73 HU left, in the intracanalicular ON portion 209 ± 88 HU right and 216 ± 101 HU left, in the intracranial ON portion 290 ± 106 HU right and 286 ± 118 HU left and in the basal cistern 517 ± 213 HU. The distribution of CLCSF along the ON showed a statistically significant reduction in the intraorbital ON segments in NTG patients compared to controls without NTG with the far largest difference within the retrobulbar segment (-150 HU right and -117 HU left; right: p < 0.001, left: p < 0.001). CONCLUSION: This study demonstrates a gradual reduction in CLCSF towards the retrobulbar segment in NTG, while in controls without NTG, no reduction in CLCSF was measured within the orbital segments. Impaired CSF dynamics along the ON may contribute to the pathophysiology of NTG.

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Presión del Líquido Cefalorraquídeo/fisiología , Líquido Cefalorraquídeo/fisiología , Glaucoma de Baja Tensión/líquido cefalorraquídeo , Anciano , Anciano de 80 o más Años , Femenino , Gonioscopía , Humanos , Hidrodinámica , Presión Intraocular , Glaucoma de Baja Tensión/diagnóstico , Glaucoma de Baja Tensión/fisiopatología , Masculino , Persona de Mediana Edad , Mielografía/métodos , Oftalmoscopía , Estudios Retrospectivos , Tomografía de Coherencia Óptica/métodos , Tomografía Computarizada por Rayos X

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IMPORTANCE: This study offers a new approach for the quantification of CSF dynamics. BACKGROUND: Non-invasive method to quantify the CSF dynamics in the subarachnoid space of the optic nerve is highly desirable. The aim of the study was to measure slow-flow CSF velocities in healthy controls and normal tension glaucoma patients between the intracranial cavity and the subarachnoid space of the optic nerve. DESIGN: Prospective observational study. PARTICIPANTS: Eleven age-matched healthy volunteers and 15 normal tension glaucoma patients. METHODS: Using phase contrast images, the phase shift in MRI diffusion images can be used to determine the flow velocity. Flow-range ratio between the intracranial cavity and the subarachnoid space of the optic nerve was calculated. MAIN OUTCOME MEASURE: Flow-range ratio between the intracranial cavity and the subarachnoid space of the optic nerve was calculated. RESULTS: First, phantom measurements were provided to validate the slow-flow velocity calculations. Second, flow-range ratio was validated for the healthy controls (0.63 ± 0.05), with the range being similar for the right and left optic nerve (P = 0.1). Statistically significant results were obtained (P < 0.05) when comparing the flow-range ratio in the optic nerve of healthy controls (n = 22 eyes, 0.63 ± 0.05) with the flow-range ratio in pathological optic nerves (n = 23, 0.55 ± 0.08) of normal tension glaucoma patients. MANOVA revealed no dependency between flow-range ratio and patient dependent variables. CONCLUSION AND RELEVANCE: Diffusion-weighted imaging provides a method to evaluate CSF flow within the subarachnoid space of the optic nerve in a non-invasive manner. Compared to healthy controls, patients with normal tension glaucoma measure a significantly lower flow-range ratio. This finding suggests a possible role of impaired CSF dynamics in the pathophysiology in normal tension glaucoma.

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Presión del Líquido Cefalorraquídeo/fisiología , Líquido Cefalorraquídeo/fisiología , Imagen de Difusión por Resonancia Magnética/métodos , Glaucoma de Baja Tensión/fisiopatología , Nervio Óptico/patología , Espacio Subaracnoideo/fisiopatología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Presión Intraocular , Glaucoma de Baja Tensión/diagnóstico , Masculino , Persona de Mediana Edad , Fantasmas de Imagen , Estudios Prospectivos

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PURPOSE: Ophthalmoplegia (OP) can have numerous etiologies and different clinical presentations. Most causes of OP can be narrowed down to specific anatomical locations based on clinical information. The aim of this study was to outline the different categories of diseases encountered in patients with OP, based on the location along the ocular motor pathways, and the most appropriate imaging modality for the given scenarios. METHODS: Representative neuroimaging examples of pathological processes causing OP are displayed, sequenced by anatomical location and disease category. Correlations between the clinical presentation and site of pathology with imaging protocol recommendations are also presented. RESULTS: Diseases affecting ocular movement can be divided into categories including: injuries or diseases of the cerebral hemispheres, midbrain, pons, and cerebellum, ocular motor nerve palsies, intrinsic extraocular muscle diseases and orbital diseases secondarily affecting the extraocular muscles. The cranial nerves responsible for ocular movements can be affected intrinsically or extrinsically along their nuclei, their course in the brainstem, in the cisterns, skull base, cavernous sinuses and orbits. The extraocular muscles can be affected primarily or secondarily by adjacent pathological processes in the orbit. Clinical information can help narrow down the differential diagnoses in terms of anatomical site of involvement and prompt the most appropriate neuroimaging techniques. CONCLUSION: By understanding the pathophysiology of OP the neuroradiologist can discuss clinical cases with the referring clinician and determine a timely, accurate method of imaging to achieve the most precise differential diagnosis.

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Imagen por Resonancia Magnética , Oftalmoplejía/diagnóstico por imagen , Nervios Craneales , Humanos , Neuroimagen , Músculos Oculomotores

RESUMEN

PURPOSE: To evaluate long-term efficacy and safety of repeated ultrasonic circular cyclocoagulation (UCCC) in patients with uncontrolled glaucoma. METHODS: Forty eyes of 40 patients affected by primary or secondary uncontrolled glaucoma under maximal tolerated medical therapy were enrolled in this prospective non-comparative case series study. A complete ophthalmic examination was performed before and after each month for 1 year. The UCCC treatment was repeated at 4 months if the intraocular pressure (IOP) was > 21 mmHg without major complications. Complete success was defined as a final IOP > 5 mmHg and ≤ 21 mmHg without hypotensive medication adjunction and no major or vision-threatening complications. RESULTS: The mean preoperative IOP was 32.5 ± 9.9 mmHg. Four months after the first UCCC treatment the overall IOP reduction was 27.8%. Twenty-two of the treated eyes did not achieve the complete success and a second treatment was performed in 20 of these eyes. Four months after the second UCCC procedure, the IOP reduction was 20.3% from preoperative values and 34.7% from baseline. Twelve of the retreated eyes needed a third treatment. Four months after the third UCCC treatment, the overall IOP reduction was 34% and 52.6% from baseline. No major complications occurred during or after any of the procedures. At 12 months, complete success was achieved in 85% (34/40) of treated eyes, with a maximum of three procedures and a significant medication reduction. CONCLUSIONS: Multiple UCCC treatments are safe, and additional treatments increase the overall procedure efficacy.

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Cuerpo Ciliar/cirugía , Glaucoma/cirugía , Ultrasonido Enfocado de Alta Intensidad de Ablación/métodos , Presión Intraocular/fisiología , Agudeza Visual , Adulto , Anciano , Anciano de 80 o más Años , Antihipertensivos/uso terapéutico , Femenino , Estudios de Seguimiento , Glaucoma/tratamiento farmacológico , Glaucoma/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento

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PURPOSE: To report on the optic canal cross-sectional area (OCA) in Caucasian patients with normal-tension glaucoma (NTG) compared with Caucasian control subjects without known optic nerve (ON) diseases. METHODS: Retrospective analysis of computed tomographic images of the cranium and orbits in 56 NTG patients (30 females and 26 males; 99 of 112 eyes; mean age 67.7 ± 11.1 years). Fifty-six age- and gender-matched subjects (mean age: 68.0 ± 11.2 years) without known ON diseases served as controls. The OCA at the orbital opening was measured in square millimeters by using the tool "freehand." Statistical analysis was performed by using the independent two-tailed t-test. RESULTS: The mean orbital opening OCA in NTGs measured 14.5 ± 3.5 mm2 (right OCA: 14.4 ± 3.6 mm2, left OCA: 14.5 ± 3.4 mm2) and in controls measured 18.3 ± 2.6 mm2 (right OCA: 18.5 ± 2.7 mm2, left OCA: 18.1 ± 2.5 mm2). The difference between NTG and controls was statistically significant (p < 0.000 for the right OCA, p < 0.000 for the left OCA). CONCLUSION: This study demonstrates narrower OCAs in Caucasian NTG patients compared with Caucasian control subjects without known ON diseases. Narrower OCAs might contribute to a discontinuity of the cerebrospinal fluid flow between the intracranial and orbital subarachnoid space in NTG patients. This might have an influence onto the pathophysiology in NTG.