Cirugía monocular de 4 músculos extraoculares para la exotropía monocular de gran ángulo / Unilateral four muscle surgery for extra-large monocular exotropia

Introducción La exotropía recurrente es común después de cirugía para exotropía sensorial monocular constante de gran ángulo. La cirugía generalmente se limita al ojo afectado. El debilitamiento simultáneo de los músculos oblicuos ipsilaterales puede mejorar el efecto de la cirugía de los músculos rectos horizontales al disminuir las fuerzas de abducción. Presentamos los resultados de la cirugía simultánea de debilitamiento de los músculos oblicuos combinados con cirugía del músculo recto horizontal ipsilateral con exotropía monocular constante superior a 35 dioptrías prismáticas (DP). Métodos Serie retrospectiva en casos de retroinserción unilateral del recto lateral combinada con resección del recto medial, y debilitamiento simultáneo de ambos músculos oblicuos ipsilaterales. La medida de resultado fue la alineación ocular en la posición primaria. Resultados Se incluyeron 12 ojos de 12 pacientes. La exotropía preoperatoria mejoró de 57,9±15,1DP (rango 35-80; mediana 60) a 3,3±5,5 (rango 0-16; mediana 0) postoperatoriamente (p<0,005). Dos (66%) pacientes con desviación vertical preexistente tuvieron una resolución de su desalineación vertical postoperatoriamente. En el último seguimiento postoperatorio, el 92% de los pacientes tenían una exodesviación de 10DP o menos y 7 (58%) midieron ortotropía. La abducción postoperatoria midió −0,6±1(0 a −3) y la aducción −0,4±0,7 (0 a −2). Conclusión El debilitamiento de los músculos oblicuos puede mejorar el efecto de la cirugía de los músculos rectos horizontales al disminuir las fuerzas de abducción en casos de exotropía monocular de gran ángulo. Como ventaja adicional, la cirugía del músculo oblicuo se puede utilizar simultáneamente para abordar las desviaciones verticales asociadas (AU)

Introduction Recurrent exotropia is common following surgery for monocular large angle constant sensory exotropia. Surgery is usually limited to operations on the affected eye. Simultaneous oblique weakening surgery may enhance the effect of the horizontal rectus muscles surgery by decreasing the abducting forces. We report the results of simultaneous oblique muscle weakening procedures combined with ipsilateral horizontal rectus muscle surgery constant monocular exotropia greater than 35 prism diopters (PD). Methods Retrospective case series of patients who underwent unilateral lateral rectus recession combined with medial rectus muscle resection and simultaneous weakening of both ipsilateral oblique muscles. Primary outcome measure was ocular alignment in primary position. Results Twelve eyes of 12 patients were included. The mean preoperative exotropia improved from 57.9±15.1 (range 35–80; median 60PD) to 3.3±5.5 (range 0–16; median 0PD) postoperatively (p<0.005). Two (66%) patients with a pre-existing vertical deviation had resolution of their vertical misalignment postoperatively. At the last postoperative follow up 92% of the patients had an exodeviation of 10PD or less (range 0–16PD median 0PD), and 7 (58%) measured near and distance orthotropia. Postoperative abduction measured −0.6±1 (0 to −3) and adduction −0.4±0.7 (0 to −2). Conclusion Weakening the ipsilateral oblique muscles may enhance the effect of the horizontal rectus muscles surgery by decreasing the abducting vectorial forces when operating for a large angle monocular exotropia. As an additional potential advantage, oblique muscle surgery may be used simultaneously to address associated vertical deviations (AU)

Unilateral four muscle surgery for extra-large monocular exotropia.

INTRODUCTION: Recurrent exotropia is common following surgery for monocular large angle constant sensory exotropia. Surgery is usually limited to operations on the affected eye. Simultaneous oblique weakening surgery may enhance the effect of the horizontal rectus muscles surgery by decreasing the abducting forces. We report the results of simultaneous oblique muscle weakening procedures combined with ipsilateral horizontal rectus muscle surgery constant monocular exotropia greater than 35 prism diopters (PD). METHODS: Retrospective case series of patients who underwent unilateral lateral rectus recession combined with medial rectus muscle resection and simultaneous weakening of both ipsilateral oblique muscles. Primary outcome measure was ocular alignment in primary position. RESULTS: Twelve eyes of 12 patients were included. The mean preoperative exotropia improved from 57.9 ±â€¯15.1 (range 35-80; median 60 PD) to 3.3 ±â€¯5.5 (range 0-16; median 0 PD) postoperatively (p < 0.005). Two of 3 patients with a pre-existing vertical deviation had resolution of their vertical misalignment postoperatively. At the last postoperative follow up 92% of the patients had an exodeviation of 10 PD or less (range 0-16 PD median 0 PD), and 7 (58%) measured near and distance orthotropia. Postoperative abduction measured -0.6 ±â€¯1 (0 to -3) and adduction -0.4 ±â€¯0.7 (0 to -2). CONCLUSION: Weakening the ipsilateral oblique muscles may enhance the effect of the horizontal rectus muscles surgery by decreasing the abducting vectorial forces when operating for a large angle monocular exotropia. As an additional potential advantage, oblique muscle surgery may be used simultaneously to address associated vertical deviations.

Characteristics of a Diverse Cohort of Stroke Patients with SARS-CoV-2 and Outcome by Sex.

BACKGROUND AND PURPOSE: Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection is associated with stroke. The role of sex on stroke outcome has not been investigated. To objective of this paper is to describe the characteristics of a diverse cohort of acute stroke patients with COVID-19 disease and determine the role of sex on outcome. METHODS: This is a retrospective study of patients with acute stroke and SARS-CoV-2 infection admitted between March 15 to May 15, 2020 to one of the six participating comprehensive stroke centers. Baseline characteristics, stroke subtype, workup, treatment and outcome are presented as total number and percentage or median and interquartile range. Outcome at discharge was determined by the modified Rankin Scale Score (mRS). Variables and outcomes were compared for males and females using univariate and multivariate analysis. RESULTS: The study included 83 patients, 47% of which were Black, 28% Hispanics/Latinos, and 16% whites. Median age was 64 years. Approximately 89% had at least one preexisting vascular risk factor (VRF). The most common complications were respiratory failure (59%) and septic shock (34%). Compared with females, a higher proportion of males experienced severe SARS-CoV-2 symptoms requiring ICU hospitalization (73% vs. 49%; p = 0.04). When divided by stroke subtype, there were 77% ischemic, 19% intracerebral hemorrhage and 3% subarachnoid hemorrhage. The most common ischemic stroke etiologies were cryptogenic (39%) and cardioembolic (27%). Compared with females, males had higher mortality (38% vs. 13%; p = 0.02) and were less likely to be discharged home (12% vs. 33%; p = 0.04). After adjustment for age, race/ethnicity, and number of VRFs, mRS was higher in males than in females (OR = 1.47, 95% CI = 1.03-2.09). CONCLUSION: In this cohort of SARS-CoV-2 stroke patients, most had clinical evidence of coronavirus infection on admission and preexisting VRFs. Severe in-hospital complications and worse outcomes after ischemic strokes were higher in males, than females.

Structural and functional motor cortex asymmetry in unilateral lower limb amputation with phantom limb pain.

OBJECTIVE: The role of motor cortex reorganization in the development and maintenance of phantom limb pain (PLP) is still unclear. This study aims to evaluate neurophysiological and structural motor cortex asymmetry in patients with PLP and its relationship with pain intensity. METHODS: Cross-sectional analysis of an ongoing randomized-controlled trial. We evaluated the motor cortex asymmetry through two techniques: i) changes in cortical excitability indexed by transcranial magnetic stimulation (motor evoked potential, paired-pulse paradigms and cortical mapping), and ii) voxel-wise grey matter asymmetry analysis by brain magnetic resonance imaging. RESULTS: We included 62 unilateral traumatic lower limb amputees with a mean PLP of 5.9 (SD = 1.79). We found, in the affected hemisphere, an anterior shift of the hand area center of gravity (23 mm, 95% CI 6 to 38, p = 0.005) and a disorganized and widespread representation. Regarding voxel-wise grey matter asymmetry analysis, data from 21 participants show a loss of grey matter volume in the motor area of the affected hemisphere. This asymmetry seems negatively associated with time since amputation. For TMS data, only the ICF ratio is negatively correlated with PLP intensity (r = -0.25, p = 0.04). CONCLUSION: There is an asymmetrical reorganization of the motor cortex in patients with PLP, characterized by a disorganized, widespread, and shifted hand cortical representation and a loss in grey matter volume in the affected hemisphere. This reorganization seems to reduce across time since amputation. However, it is not associated with pain intensity. SIGNIFICANCE: These findings are significant to understand the role of the motor cortex reorganization in patients with PLP, showing that the pain intensity may be related with other neurophysiological factors, not just cortical reorganization.

Cortical plasticity in phantom limb pain: A fMRI study on the neural correlates of behavioral clinical manifestations.

The neural mechanism of phantom limb pain (PLP) is related to the intense brain reorganization process implicating plasticity after deafferentation mostly in sensorimotor system. There is a limited understanding of the association between the sensorimotor system and PLP. We used a novel task-based functional magnetic resonance imaging (fMRI) approach to (1) assess neural activation within a-priori selected regions-of-interested (motor cortex [M1], somatosensory cortex [S1], and visual cortex [V1]), (2) quantify the cortical representation shift in the affected M1, and (3) correlate these changes with baseline clinical characteristics. In a sample of 18 participants, we found a significantly increased activity in M1 and S1 as well as a shift in motor cortex representation that was not related to PLP intensity. In an exploratory analyses (not corrected for multiple comparisons), they were directly correlated with time since amputation; and there was an association between increased activity in M1 with a lack of itching sensation and V1 activation was negatively correlated with PLP. Longer periods of amputation lead to compensatory changes in sensory-motor areas; and itching seems to be a protective marker for less signal changes. We confirmed that PLP intensity is not associated with signal changes in M1 and S1 but in V1.

Anterior segment ischemia: etiology, assessment, and management.

Anterior segment ischemia (ASI) is a potentially serious but rare complication of strabismus surgery. Among several risk factors, ASI occurs after strabismus surgery because of the nature of the anterior segment circulation. Disinsertion of rectus muscles leads to a decrease in the blood supply to the various anterior segment structures. We report a series of retrospective and prospective studies performed by our group focused on determining the risk of anterior segment ischemia following strabismus surgery, diagnosis, and modifications to surgical techniques to minimize the impact on anterior segment circulation. We found a significant decrease in postoperative anterior segment blood flow when operating vertical rectus muscles. Plication procedures preserve anterior segment circulation, and modifications to the technique allow the performance of adjustable sutures. Small adjustable selective procedures that spare the ciliary vessels have been demonstrated to be effective in patients with vertical and torsional diplopia. Ciliary sparing augmented adjustable transposition surgery decreases the risk of anterior segment ischemia while allowing management of potential post-operative alignment complications. Finally, ocular coherence tomography angiography is a valuable quantitative and qualitative technique to evaluate anterior segment ischemia. Strabismus surgeons should be aware of the risks of anterior segment ischemia when operating vertical rectus muscles. Modifications to standard surgical techniques allow surgeons to perform complex strabismus surgery in patients at risk for anterior segment ischemia.

Importance of sagittal orbital imaging in evaluating extraocular muscle trauma following endoscopic sinus surgery.

BACKGROUND/AIMS: Orbital trauma may result in severe restrictive, paralytic, or combined strabismus. Clinical diagnosis may be extremely challenging. Orbital imaging is helpful in determining the exact site of injury, functionality, and integrity of the extraocular muscles. A typical study now includes coronal and axial views of the muscles. This study aimed to emphasise the importance of sagittal imaging of the orbit when evaluating extraocular muscle injury or entrapment. METHODS: A retrospective review of two subjects who underwent endoscopic sinus surgery procedures that resulted in trauma to the medial rectus muscle. High resolution orbital imaging studies were performed. RESULTS: High resolution magnetic resonance imaging (MRI) scans with coronal and axial views suggested a large section of the muscle was not present and was probably destroyed. In both cases there was a displacement of the mid-portion of the medial rectus muscle into an area of bony defect not seen on the axial and coronal views. Sagittal images demonstrated continuity between the anterior and posterior segments of the medial rectus muscle in each case. CONCLUSION: Surgical strategies are dependent on accurate interpretation of MRI scans. Muscle displacement may result in axial and coronal orbital imaging misinterpretation. Sagittal views were essential to determine muscle integrity.

Timing of postoperative adjustment in adjustable suture strabismus surgery.

PURPOSE: The use of adjustable sutures in strabismus surgery has increased the rate of surgical success. Little data are available on the optimum timing for postoperative adjustment after strabismus surgery. We wanted to compare 2 common practices of adjustable suture technique after strabismus surgery. METHODS: Two comparable groups of 40 patients each, who had strabismus surgery with adjustable suture technique, were prospectively studied. Group A had early adjustment the same day of the surgery about 6 hours after the operation, and group B had late adjustment the next day about 24 hours after the operation. Subjective scoring tables were used to evaluate the pain felt by the patient before, during, and after the adjustment and any difficulties of the adjustment process. Requirements of postoperative pain medications and final alignment 6 weeks after surgery were also compared. RESULTS: Despite adequate statistical power, no significant differences were found between the groups regarding pain before, during, and after adjustment, difficulties performing the adjustment, and final alignment after 6 weeks (P > .05). Both adjustment schedules were equally associated with mild to moderate pain before, during, and after the adjustment. In the first 24 hours after surgery, no overall difference in the use of pain medications was found. Nausea and vomiting in the first 24 postoperative hours were more common in the early adjustment group (P = .02). CONCLUSION: The surgeon can feel free to choose the timing for postoperative adjustment. However, when performing an early adjustment, the surgeon should be especially prepared to control nausea and vomiting.

Vertical rectus muscle augmented transposition in Duane syndrome.

INTRODUCTION: Reduction or elimination of face turn and esotropia in the primary position while maintaining the largest possible diplopia-free field are the major surgical goals in Duane syndrome with esotropia. Unsatisfactory postoperative results may occur because of limitation in adduction, poor abduction, or induced vertical deviations. Recent reports have shown enhanced results from rectus muscle transposition techniques when a lateral posterior augmentation fixation is placed. METHODS: Preoperative and postoperative data of 2 groups of subjects who had Duane syndrome with esotropia in primary position and markedly reduced abduction were comparatively analyzed. Group A consisted of subjects who had transposition of both vertical rectus muscles to the lateral rectus muscle with a posterior lateral augmentation suture placed in each transposed muscle. Group B subjects had transposition of both vertical rectus muscles to the lateral rectus muscle without the posterior lateral augmentation suture. RESULTS: A total of 32 subjects in group A and 22 subjects in group B were analyzed. In group A, anomalous head position improved 19.1 degrees +/- 10.3 degrees compared with group B subjects who improved 10.6 degrees +/- 5.8 degrees (P <.05). In group A, esotropia in primary position improved 16.4 +/- 9.2 PD compared with group B subjects who improved 8.5 +/- 6.9 PD (P <.05). CONCLUSIONS: Subjects with Duane syndrome and esotropia in primary position who had undergone augmented transposition of the vertical rectus muscles obtained improved head position and better alignment in primary position and had a reduction in the incidence of reoperation for undercorrection when compared with similar patients who had undergone vertical rectus muscle transposition without posterior lateral augmentation sutures.

Facial asymmetry in superior oblique muscle palsy and pulley heterotopy.

INTRODUCTION: Some observers have considered facial asymmetry as characteristic of congenital superior oblique muscle (SO) palsy. However, recent orbital imaging studies have determined that incomitant vertical strabismus resembling SO palsy can be caused by heterotopic rectus muscle pulleys. This finding suggests that facial asymmetry may predict the presence of abnormal orbital anatomy rather than be secondary to ocular torticollis. METHODS: Subjects who underwent orbital computed tomography or magnetic resonance imaging were divided into 5 groups based on clinical evaluation and previously established imaging criteria: (1) congenital SO palsy; (2) acquired SO palsy; (3) strabismus with pulley heterotopy; (4) strabismus without SO palsy or pulley heterotopy; and (5) orthotropic subjects. Frontal photographs were digitized and the following 3 facial morphometric features recorded: (1) angle of inclination of each orbit; (2) relative facial size; and (3) facial angle. RESULTS: The 79 subjects who underwent imaging were divided into the 5 groups as follows: 6 with congenital SO palsy; 7 with acquired SO palsy; 20 with pulley heterotopy; 26 with strabismus without SO palsy or pulley heterotopy; and 20 control subjects. All subjects with either congenital or acquired SO palsy had torticollis. Multivariate analysis demonstrated no significant differences in any of the 3 facial morphometric features among any of the groups. CONCLUSION: Facial asymmetry as assessed by these 3 morphometric features is not useful in distinguishing between congenital SO palsy or pulley heterotopy and other acquired forms of strabismus. This finding casts doubt on the relationship between ocular torticollis and facial asymmetry.