Table 3.

Previous studies on the aetiology of fourth cranial nerve palsy.

	Country	Publication date	Studied duration	No. of cases	Aetiology (%)
					Trauma	Tumour	Vascular	Congenital	Unknown	Other
Rucker et al. [32, 33]	USA	1966	1958–1964	84	27	8	16		22	16
Rush et al. [30]	USA	1981	1966–1978	172	32	4	19		36	9
Richards et al. [8]	USA	1992	1978–1988	578	29	5	18		32	16
Dosunmu et al. [9]	USA	2018	1978–1992	74	18	1	24	49	4	1
Von Noorden et al. [1]	USA	1986	1973–1984	270	34			40	23	3
Mansour and Reinecke [4]	Spain	1986	1972–1981	82	34	1	2	52	6	4
Keane [29]	USA	1993	1970–1993	215	53	7	4	1	0	36
Gunderson et al. [7]	USA	2001	1968–1999	124	26	2	6	28	38
Mollan et al. [2]	UK	2009	1999–2005	150	33	3	21	35	9	1
Bagheri et al. [3]	Iran	2010	1997–2007	73	16			77		7
Ray et al. [6]	India	2014	2001–2008	181	34	1	9	33	24	0
Current study	Korea		2006–2015	390	5	3	51	20	19	2