Comparison between nerve conduction study and high-resolution ultrasonography with color doppler in type 1 and type 2 leprosy reactions

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Identifying leprosy reactions is important to prevent disability.

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HRUS with CD can be useful compared to NCS to diagnose acute inflammatory activity.

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HRUS with CD helps reactions diagnosis in minimal and complete NCS abnormalities.

Objective

To analyze the role of high-resolution ultrasonography with color Doppler (HRUS with CD) to diagnose inflammatory activity (IA) in nerves of leprosy patients under type 1 (RT1) and 2 (RT2) reactions compared to Nerve Conduction Studies (NCS).

Methods

Leprosy patients with signs or symptoms suggestive of neuritis (RT1 and RT2) without corticosteroids use were selected. They were evaluated by NCS and subsequently by HRUS with CD. Subacute segmental demyelination and the presence of blood flow, respectively, were considered signs of IA. The two methods were compared for their ability to diagnose patients with leprosy reactions.

Results

A total of 257 nerves from 35 patients were evaluated. NCS and HRUS with CD diagnosed IA in 68% and 74% of patients, respectively. When both methods were used concomitantly, the diagnosis rate was 91.4%. HRUS with CD was particular helpful when there was minimal neurophysiological compromise in NCS or when motor potentials were not detected.

Conclusion

HRUS with CD was able to detect leprosy reactions, especially when combined with NCS. It was especially useful in two opposite situations: nerves with only minor changes and those without motor response in NCS.

Significance

Our data shows the usefulness of HRUS and CD, similar to NCS, as a tool to diagnose leprosy reactions.

Clinical and genetic features of nonsyndromic autosomal dominant sensorineural hearing loss: KCNQ4 is a gene responsible in Japanese

Sixteen Japanese nonsyndromic autosomal dominant sensorineural hearing loss (ADSNHL) families were investigated clinically as well as genetically. Most families showed postlingual hearing loss. Although the severity of their hearing loss varied, most patients showed mild-moderate sensorineural hearing loss of a progressive nature. Mutation analysis was performed for the MYO7A, KCNQ4, and GJB3 genes, which are known to be responsible for autosomal dominant sensorineural hearing loss. The present study reports that a mutation in KCNQ4, a member of a large family of potassium channel genes, was responsible for ADSNHL in one Japanese family.

Prevalence of mitochondrial gene mutations among hearing impaired patients

The frequency of three mitochondrial point mutations, 1555A-->G, 3243A-->G, and 7445A-->G, known to be associated with hearing impairment, was examined using restriction fragment length polymorphism (RFLP) analysis in two Japanese groups: (1) 319 unrelated SNHL outpatients (including 21 with aminoglycoside antibiotic injection history), and (2) 140 cochlear implantation patients (including 22 with aminoglycoside induced hearing loss). Approximately 3% of the outpatients and 10% of the cochlear implantation patients had the 1555A-->G mutation. The frequency was higher in the patients with a history of aminoglycoside injection (outpatient group 33%, cochlear implantation group 59%). One outpatient (0.314%) had the 3243A-->G mutation, but no outpatients had the 7445A-->G mutation and neither were found in the cochlear implantation group. The significance of the 1555A-->G mutation, the most prevalent mitochondrial mutation found in this study of a hearing impaired population in Japan, among subjects with specific backgrounds, such as aminoglycoside induced hearing loss, is evident.

Age and increased incidence of "forward bowing" of the iris in normal eyes

PURPOSE AND METHODS

The incidence of forward bowing of the iris, width of the iridocorneal angle, and distance between the apex of the angle and the scleral spur were studied using high-frequency (50 MHz) ultrasound B-scan images in 90 normal eyes from Japanese volunteers.

RESULTS

The incidence of forward bowing of the iris, defined as a 120-micron anterior shifting of the posterior profile of the iris, increased from 0% in subjects under 31 years old to 50% in subjects 71 years of age and older. The iridocorneal angle was significantly narrower and the distance between the apex of the angle and the scleral spur was significantly less in eyes with forward bowing. Of the risk factors (age, axial length, sex, and corneal curvature), age (p = 0.0005) was the most significant risk factor for forward bowing of the iris.

CONCLUSION

Forward bowing of the iris is not uncommon in the elderly. Half of the Japanese subjects in this study 71 years of age and older had this condition, even though they had no optic nerve atrophy or elevation in intraocular pressure (IOP) at the time of examination.

Comparison of ciliary sulcus fixation techniques for posterior chamber intraocular lenses

OBJECTIVE

To anatomically and histologically evaluate suturing techniques for sulcus fixation of posterior chamber intraocular lenses.

SETTING

Kitano Hospital, Osaka, Japan.

METHODS

The reproducibility of three suturing techniques (perpendicular to the eye wall; parallel to the iris; midway between perpendicular to the eye wall and parallel to the iris) were evaluated in a postmortem eye. Histologic sections of another eye and ultrasound biomicroscopy (UBM) images of 21 normal eyes were evaluated to determine the safety zone for the needle to avoid damaging adjacent structures.

RESULTS

The ciliary sulcus was completely penetrated in the three techniques in 100, 40, and 70% of cases, respectively. The histologic sections and the UBM images showed that when sutures were placed perpendicular to the eye wall, there was the possibility of postoperative angle closure and suturing parallel to the iris might damage adjacent structures because of a narrow safety zone.

CONCLUSIONS

The needle should penetrate obliquely, as in the technique in which the suturing is midway between perpendicular to the eye wall and parallel to the iris. This technique provides better reproducibility and causes less damage to adjacent tissue.

Angle closure caused by multiple, bilateral iridociliary cysts

A case of high, broad, peripheral anterior synechiae caused by multiple, bilateral iridociliary cysts is reported. The peripheral anterior synechia in our case extended to the corneal endothelium beyond Schwalbe's line, and iris atrophy in the region of the cysts was found. Ultrasound biomicroscopic imaging showed that multiple, bilateral iridociliary cysts causes elevation of the iris structure.

[Follow-up study of vestibular neuronitis]

A follow-up study of 26 patients with vestibular neuronitis is reported. The disease is characterized by an acute attack of severe vertigo with complete loss of unilateral caloric response. The following results were obtained: 1) The average period of spontaneous nystagmus was 136 days and the standard error was 39 days. 2) No correlation could be found between age and the period of spontaneous nystagmus. 3) Six patients showed direction reversal in their spontaneous nystagmus (recovery nystagmus), and their outcome was good. 4) On the most recent caloric test, 42% of the patients had bilateral normal responses, 27% displayed partial improvement on the affected side, and no reaction was observed in 31% of patients. We suggest that three types of clinical courses may occur in vestibular neuronitis: i) complete recovery of the function of the affected vestibular nerve, ii) partial recovery of vestibular function, and iii) no recovery of the affected vestibular nerve, but central nervous system compensates for the vestibular imbalance.