Blockage pattern of longitudinal flow in Meniere's disease

Figures & data

Figure 1. Strategy of 3D CT images for assessing the patency of the bony groove in which the membranous labyrinth lodges. When the non-radiodense substances such as soft tissue dislodges on the membranous labyrinth on the bony groove, the 3D CT image shows the continuity of the bony groove (A, left), but in case of the radiodense substances such as otoconia, the 3D CT image loses the continuity of the bony groove (A, right). (B) 3D CT images of the reuniting duct of cadaver specimen treated with meat fragments and (C) that treated with CaCO₃. Note the differences in the continuity of the bony grooves (yellow arrowheads).

Table I. Distribution of the bony groove of the reuniting duct (BRD), saccular duct (BSD), and endolymphatic sinus (BES) of the temporal bones of patients with Meniere's disease and healthy volunteers.

		Meniere's disease
	Type	Affected ear	Non-affected ear	Ears of healthy volunteers
BRD	1	2	13	18
	2	7	12	8
	Total of 1 + 2	9	25	26
	3	12	9	0
	4	8	7	0
	5	13	17	0
	6	20	4	0
	Total of 3–6	53	37	0
BSD	SD1	18	30	23
	SD2	11	12	3
	SD3	33	20	0
	Total of SD2 + SD3	44	32	3
BES	ES1	10	28	24
	ES2	13	19	2
	ES3	39	15	0
	Total of ES2 + ES3	52	34	2

Figure 2. Evaluation points of the temporal bone (arrows). BES, bony groove of endolymphatic sinus; BRD, bony groove of reuniting duct; BSD, bony groove of saccular duct; BSR, bony groove of saccular recess; CC, common crus; IAC, internal auditory canal; P, posterior semicircular canal.

Figure 3. Occlusion patterns of bony grooves of reuniting duct (BRD). BRD1, patent throughout the entire length; BRD2, acute angle showing V-like character; BRD3, occluded at the orifice; BRD4, occluded at the middle portion of the groove; BRD5, occluded at the orifice and middle portion of the groove; BRD 6, totally occluded. Yellow arrowheads show the occluded points.

Figure 4. Occlusion patterns of the bony grooves of the saccular duct (BSD, yellow arrowhead) and endoloymphatic sinus (BES, red arrowhead). Dashed line shows original, normal diameter of BSD and BES. (A) BSD1, BES1; (B) BSD2, BES1; (C) BSD3, BES1. (See the Results section.)

Figure 5. Distribution pattern of the bony groove of the reuniting duct (BRD) in affected and contralateral non-affected side ears of patients with Meniere's disease (MD) and ears of healthy volunteers defined with BRD1–BRD6 (A) and defined with BRD1–2 and BRD3–6 (B). *p < 0.01.

Figure 6. Distribution pattern of the bony groove of the saccular duct (BSD) in affected and contralateral non-affected side ears of patients with Meniere's disease (MD) and ears of healthy volunteers defined with BSD1–BSD 3 (A) and defined with BSD1 and BSD2–3 (B). *p < 0.01; **p < 0.05.

Figure 7. Distribution pattern of the bony groove of the saccular duct (BES) in affected and contralateral non-affected side ears of patients with Meniere's disease (MD) and ears of healthy volunteers defined with BES1–BES 3 (A) and defined with BES1 and BES2–3 (B). *p < 0.01.

Table II. p values for the bony groove of the reuniting duct (BRD), saccular duct (BSD), and endolymphatic sinus (BES) for each stage of Meniere's disease.

Inter-stage	BRD	BSD	BES
1–2	0.365	<0.05**	0.79
1–3	0.628	0.28	0.69
1–4	0.44	0.8	0.68
2–3	0.324	<0.05**	0.98
2–4	0.89	<0.01*	0.74
3–4	0.4	0.053	0.58

In this table, BRD1 and BRD2 are assessed in the same patent bony groove category. *p < 0.01, **p < 0.05.